├── .gitignore
├── banner.png
├── test
    ├── catch.cpp
    ├── mirror_x.cpp
    ├── mirror_y.cpp
    ├── shift_x.cpp
    ├── shift_y.cpp
    ├── replicate.cpp
    ├── select_disk.cpp
    ├── merge.cpp
    ├── hash.cpp
    ├── select_rectangle.cpp
    ├── convert.cpp
    ├── mask_isolated.cpp
    ├── stitch.cpp
    ├── average_position.cpp
    ├── compute_activity.cpp
    ├── mask_redundant.cpp
    ├── track_blob.cpp
    ├── compute_flow.cpp
    ├── average_grid.cpp
    ├── compute_time_surface.cpp
    └── track_blob_multi.cpp
├── .gitmodules
├── source
    ├── mirror_x.hpp
    ├── mirror_y.hpp
    ├── shift_x.hpp
    ├── shift_y.hpp
    ├── select_disk.hpp
    ├── convert.hpp
    ├── mask_redundant.hpp
    ├── select_rectangle.hpp
    ├── replicate.hpp
    ├── mask_isolated.hpp
    ├── average_position.hpp
    ├── average_grid.hpp
    ├── compute_activity.hpp
    ├── stitch.hpp
    ├── track_blob.hpp
    ├── compute_time_surface.hpp
    ├── hash.hpp
    ├── track_blob_multi.hpp
    ├── compute_flow.hpp
    └── merge.hpp
├── premake4.lua
├── .travis.yml
├── README.md
├── .clang-format
├── template.lua
└── LICENSE.txt


/.gitignore:
--------------------------------------------------------------------------------
1 | build/
2 | .DS_STORE
3 | 


--------------------------------------------------------------------------------
/banner.png:
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https://raw.githubusercontent.com/neuromorphic-paris/tarsier/HEAD/banner.png


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/test/catch.cpp:
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1 | #define CATCH_CONFIG_MAIN
2 | #include "../third_party/Catch2/single_include/catch.hpp"
3 | 


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/.gitmodules:
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1 | [submodule "third_party/Catch2"]
2 | 	path = third_party/Catch2
3 | 	url = https://github.com/catchorg/Catch2.git
4 | [submodule "third_party/json.lua"]
5 | 	path = third_party/json.lua
6 | 	url = https://github.com/rxi/json.lua.git
7 | 


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/test/mirror_x.cpp:
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 1 | #include "../source/mirror_x.hpp"
 2 | #include "../third_party/Catch2/single_include/catch.hpp"
 3 | 
 4 | struct event {
 5 |     uint16_t x;
 6 | };
 7 | 
 8 | TEST_CASE("Invert the x coordinate", "[mirror_x]") {
 9 |     auto mirror_x = tarsier::make_mirror_x<event>(320, [](event event) -> void { REQUIRE(event.x == 100); });
10 |     mirror_x(event{219});
11 | }
12 | 


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/test/mirror_y.cpp:
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 1 | #include "../source/mirror_y.hpp"
 2 | #include "../third_party/Catch2/single_include/catch.hpp"
 3 | 
 4 | struct event {
 5 |     uint16_t y;
 6 | };
 7 | 
 8 | TEST_CASE("Invert the y coordinate", "[mirror_y]") {
 9 |     auto mirror_y = tarsier::make_mirror_y<event>(240, [](event event) -> void { REQUIRE(event.y == 100); });
10 |     mirror_y(event{139});
11 | }
12 | 


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/test/shift_x.cpp:
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 1 | #include "../source/shift_x.hpp"
 2 | #include "../third_party/Catch2/single_include/catch.hpp"
 3 | 
 4 | struct event {
 5 |     uint64_t x;
 6 | };
 7 | 
 8 | TEST_CASE("Shift the x coordinate", "[shift_x]") {
 9 |     auto shift_x = tarsier::make_shift_x<event>(320, 10, [](event event) -> void { REQUIRE(event.x == 210); });
10 |     shift_x(event{315});
11 |     shift_x(event{200});
12 | }
13 | 


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/test/shift_y.cpp:
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 1 | #include "../source/shift_y.hpp"
 2 | #include "../third_party/Catch2/single_include/catch.hpp"
 3 | 
 4 | struct event {
 5 |     uint64_t y;
 6 | };
 7 | 
 8 | TEST_CASE("Shift the y coordinate", "[shift_y]") {
 9 |     auto shift_y = tarsier::make_shift_y<event>(240, 10, [](event event) -> void { REQUIRE(event.y == 145); });
10 |     shift_y(event{235});
11 |     shift_y(event{135});
12 | }
13 | 


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/test/replicate.cpp:
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 1 | #include "../source/replicate.hpp"
 2 | #include "../third_party/Catch2/single_include/catch.hpp"
 3 | 
 4 | struct event {};
 5 | 
 6 | TEST_CASE("Replicate an event and trigger several callbacks", "[replicate]") {
 7 |     std::size_t count = 0;
 8 |     auto replicate =
 9 |         tarsier::make_replicate<event>([&count](event) { ++count; }, [&](event) { ++count; }, [&](event) { ++count; });
10 |     replicate(event{});
11 |     REQUIRE(count == 3);
12 | }
13 | 


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/test/select_disk.cpp:
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 1 | #include "../source/select_disk.hpp"
 2 | #include "../third_party/Catch2/single_include/catch.hpp"
 3 | 
 4 | struct event {
 5 |     uint16_t x;
 6 |     uint16_t y;
 7 | };
 8 | 
 9 | TEST_CASE("Filter out events outside the disk", "[select_disk]") {
10 |     auto select_disk =
11 |         tarsier::make_select_disk<event>(100, 100, 20.0, [](event event) -> void { REQUIRE(event.x == 100); });
12 |     select_disk(event{200, 200});
13 |     select_disk(event{100, 110});
14 | }
15 | 


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/test/merge.cpp:
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 1 | #include "../source/merge.hpp"
 2 | #include "../third_party/Catch2/single_include/catch.hpp"
 3 | 
 4 | struct event {
 5 |     uint64_t t;
 6 | };
 7 | 
 8 | TEST_CASE("Merge two streams", "[merge]") {
 9 |     std::size_t index = 0;
10 |     auto merge = tarsier::make_merge<2, event>(256, std::chrono::milliseconds(20), [&](event event) -> void {
11 |         REQUIRE(event.t == index);
12 |         ++index;
13 |     });
14 |     merge->push<0>(event{1});
15 |     merge->push<1>(event{0});
16 | }
17 | 


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/test/hash.cpp:
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 1 | #include "../source/hash.hpp"
 2 | #include "../third_party/Catch2/single_include/catch.hpp"
 3 | #include <vector>
 4 | 
 5 | TEST_CASE("Hash a list of numbers", "[hash]") {
 6 |     auto hash = tarsier::make_hash<uint8_t>([](std::pair<uint64_t, uint64_t> hash) -> void {
 7 |         REQUIRE(std::get<0>(hash) == 0xb06f9999c14051caull);
 8 |         REQUIRE(std::get<1>(hash) == 0x0fbd6d93c8340799ull);
 9 |     });
10 |     for (uint8_t index = 0; index < 100; ++index) {
11 |         hash(index);
12 |     }
13 | }
14 | 


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/test/select_rectangle.cpp:
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 1 | #include "../source/select_rectangle.hpp"
 2 | #include "../third_party/Catch2/single_include/catch.hpp"
 3 | 
 4 | struct event {
 5 |     uint16_t x;
 6 |     uint16_t y;
 7 | };
 8 | 
 9 | TEST_CASE("Filter out events outside the rectangle", "[select_rectangle]") {
10 |     auto select_rectangle =
11 |         tarsier::make_select_rectangle<event>(50, 50, 204, 140, [](event event) -> void { REQUIRE(event.x == 100); });
12 |     select_rectangle(event{300, 200});
13 |     select_rectangle(event{100, 100});
14 | }
15 | 


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/test/convert.cpp:
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 1 | #include "../source/convert.hpp"
 2 | #include "../third_party/Catch2/single_include/catch.hpp"
 3 | 
 4 | struct event {
 5 |     bool is_increase;
 6 | };
 7 | 
 8 | struct converted_event {
 9 |     bool polarity;
10 | };
11 | 
12 | TEST_CASE("Convert an event type to another", "[convert]") {
13 |     auto convert = tarsier::make_convert<event>(
14 |         [](event event) -> converted_event { return {event.is_increase}; },
15 |         [](converted_event converted_event) -> void { REQUIRE(converted_event.polarity); });
16 |     convert(event{true});
17 | }
18 | 


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/test/mask_isolated.cpp:
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 1 | #include "../source/mask_isolated.hpp"
 2 | #include "../third_party/Catch2/single_include/catch.hpp"
 3 | 
 4 | struct event {
 5 |     uint64_t t;
 6 |     uint16_t x;
 7 |     uint16_t y;
 8 | };
 9 | 
10 | TEST_CASE("Filter out events with low spatial or temporal activity", "[mask_isolated]") {
11 |     auto mask_isolated =
12 |         tarsier::make_mask_isolated<event>(320, 240, 10, [](event event) -> void { REQUIRE(event.x == 100); });
13 |     mask_isolated(event{0, 200, 200});
14 |     mask_isolated(event{1, 200, 202});
15 |     mask_isolated(event{20, 200, 201});
16 |     mask_isolated(event{40, 100, 100});
17 |     mask_isolated(event{41, 100, 101});
18 | }
19 | 


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/test/stitch.cpp:
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 1 | #include "../source/stitch.hpp"
 2 | #include "../third_party/Catch2/single_include/catch.hpp"
 3 | 
 4 | struct threshold_crossing {
 5 |     uint64_t t;
 6 |     uint16_t x;
 7 |     uint16_t y;
 8 |     bool is_second;
 9 | };
10 | 
11 | struct event {
12 |     uint16_t x;
13 |     uint16_t y;
14 |     uint64_t delta_t;
15 | };
16 | 
17 | TEST_CASE("Stitch an threshold crossings stream", "[stitch]") {
18 |     auto stitch = tarsier::make_stitch<threshold_crossing, event>(
19 |         320,
20 |         240,
21 |         [](threshold_crossing threshold_crossing, uint64_t delta_t) -> event {
22 |             return {threshold_crossing.x, threshold_crossing.y, delta_t};
23 |         },
24 |         [](event event) -> void { REQUIRE(event.delta_t == 200); });
25 |     stitch(threshold_crossing{0, 200, 100, false});
26 |     stitch(threshold_crossing{100, 200, 0, false});
27 |     stitch(threshold_crossing{200, 200, 100, true});
28 | }
29 | 


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/test/average_position.cpp:
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 1 | #include "../source/average_position.hpp"
 2 | #include "../third_party/Catch2/single_include/catch.hpp"
 3 | 
 4 | struct event {
 5 |     uint16_t x;
 6 |     uint16_t y;
 7 | };
 8 | 
 9 | struct position {
10 |     float x;
11 |     float y;
12 | };
13 | 
14 | TEST_CASE("Average the position of the given events", "[average_position]") {
15 |     auto first_received = false;
16 |     auto average_position = tarsier::make_average_position<event, position>(
17 |         0.0,
18 |         0.0,
19 |         0.5,
20 |         [](event event, float x, float y) -> position {
21 |             return {x, y};
22 |         },
23 |         [&](position position) -> void {
24 |             if (first_received) {
25 |                 REQUIRE(position.x == 100);
26 |                 REQUIRE(position.y == 50);
27 |             } else {
28 |                 first_received = true;
29 |             }
30 |         });
31 |     average_position(event{0, 0});
32 |     average_position(event{200, 100});
33 | }
34 | 


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/test/compute_activity.cpp:
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 1 | #include "../source/compute_activity.hpp"
 2 | #include "../third_party/Catch2/single_include/catch.hpp"
 3 | 
 4 | struct event {
 5 |     uint64_t t;
 6 |     uint16_t x;
 7 |     uint16_t y;
 8 | };
 9 | 
10 | struct activity {
11 |     uint64_t t;
12 |     uint16_t x;
13 |     uint16_t y;
14 |     float potential;
15 | };
16 | 
17 | TEST_CASE("compute the activity from the given events", "[compute_activity]") {
18 |     std::vector<float> expected_potentials{1.0f, 1.9999000049998332f, 1.0f, 1.9999000049998332f, 1.0000908225624412f};
19 |     std::size_t index = 0;
20 |     auto compute_activity = tarsier::make_compute_activity<event, activity>(
21 |         320,
22 |         240,
23 |         10000,
24 |         [](event event, float potential) -> activity {
25 |             return {event.t, event.x, event.y, potential};
26 |         },
27 |         [&](activity activity) -> void {
28 |             REQUIRE(std::abs(activity.potential - expected_potentials[index]) / expected_potentials[index] < 1e-3);
29 |             ++index;
30 |         });
31 |     compute_activity(event{100000, 100, 100});
32 |     compute_activity(event{100001, 100, 100});
33 |     compute_activity(event{100002, 101, 100});
34 |     compute_activity(event{100003, 101, 100});
35 |     compute_activity(event{200000, 101, 100});
36 | }
37 | 


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/test/mask_redundant.cpp:
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 1 | #include "../source/mask_redundant.hpp"
 2 | #include "../third_party/Catch2/single_include/catch.hpp"
 3 | 
 4 | struct event {
 5 |     uint16_t x;
 6 |     uint16_t y;
 7 |     uint64_t t;
 8 |     bool is_increase;
 9 | };
10 | 
11 | TEST_CASE("Filter successive similar events close in time", "[mask_redundant]") {
12 |     uint16_t n_event_output = 0;
13 |     auto mask_redundant = tarsier::make_mask_redundant<event>(320, 240, 50, [&](event event) -> void {
14 |         switch (n_event_output) {
15 |             case 0:
16 |                 REQUIRE(event.t == 100);
17 |                 break;
18 |             case 1:
19 |                 REQUIRE(event.t == 140);
20 |                 break;
21 |             case 2:
22 |                 REQUIRE(event.t == 200);
23 |                 break;
24 |             case 3:
25 |                 REQUIRE(event.t == 210);
26 |                 break;
27 |             default:
28 |                 throw std::logic_error("Unexpected value");
29 |         }
30 |         n_event_output++;
31 |     });
32 |     mask_redundant(event{101, 51, 100, true});
33 |     mask_redundant(event{101, 51, 120, true});
34 |     mask_redundant(event{101, 52, 140, true});
35 |     mask_redundant(event{201, 21, 200, true});
36 |     mask_redundant(event{201, 21, 210, false});
37 |     REQUIRE(n_event_output == 4);
38 | }
39 | 


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/source/mirror_x.hpp:
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 1 | #pragma once
 2 | 
 3 | #include <cstdint>
 4 | #include <utility>
 5 | 
 6 | /// tarsier is a collection of event handlers.
 7 | namespace tarsier {
 8 | 
 9 |     /// mirror_x inverts the x coordinate.
10 |     template <typename Event, typename HandleEvent>
11 |     class mirror_x {
12 |         public:
13 |         mirror_x(uint16_t width, HandleEvent&& handle_event) :
14 |             _width(width),
15 |             _handle_event(std::forward<HandleEvent>(handle_event)) {}
16 |         mirror_x(const mirror_x&) = delete;
17 |         mirror_x(mirror_x&&) = default;
18 |         mirror_x& operator=(const mirror_x&) = delete;
19 |         mirror_x& operator=(mirror_x&&) = default;
20 |         virtual ~mirror_x() = default;
21 | 
22 |         /// operator() handles an event.
23 |         virtual void operator()(Event event) {
24 |             event.x = _width - 1 - event.x;
25 |             _handle_event(event);
26 |         }
27 | 
28 |         protected:
29 |         const uint16_t _width;
30 |         HandleEvent _handle_event;
31 |     };
32 | 
33 |     /// make_mirror_x creates a mirror_x from a functor.
34 |     template <typename Event, typename HandleEvent>
35 |     inline mirror_x<Event, HandleEvent> make_mirror_x(uint16_t width, HandleEvent&& handle_event) {
36 |         return mirror_x<Event, HandleEvent>(width, std::forward<HandleEvent>(handle_event));
37 |     }
38 | }
39 | 


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/source/mirror_y.hpp:
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 1 | #pragma once
 2 | 
 3 | #include <cstdint>
 4 | #include <utility>
 5 | 
 6 | /// tarsier is a collection of event handlers.
 7 | namespace tarsier {
 8 | 
 9 |     /// mirror_y inverts the y coordinate.
10 |     template <typename Event, typename HandleEvent>
11 |     class mirror_y {
12 |         public:
13 |         mirror_y(uint16_t height, HandleEvent&& handle_event) :
14 |             _height(height),
15 |             _handle_event(std::forward<HandleEvent>(handle_event)) {}
16 |         mirror_y(const mirror_y&) = delete;
17 |         mirror_y(mirror_y&&) = default;
18 |         mirror_y& operator=(const mirror_y&) = delete;
19 |         mirror_y& operator=(mirror_y&&) = default;
20 |         virtual ~mirror_y() = default;
21 | 
22 |         /// operator() handles an event.
23 |         virtual void operator()(Event event) {
24 |             event.y = _height - 1 - event.y;
25 |             _handle_event(event);
26 |         }
27 | 
28 |         protected:
29 |         const uint16_t _height;
30 |         HandleEvent _handle_event;
31 |     };
32 | 
33 |     /// make_mirror_y creates a mirror_y from a functor.
34 |     template <typename Event, typename HandleEvent>
35 |     inline mirror_y<Event, HandleEvent> make_mirror_y(uint16_t height, HandleEvent&& handle_event) {
36 |         return mirror_y<Event, HandleEvent>(height, std::forward<HandleEvent>(handle_event));
37 |     }
38 | }
39 | 


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/premake4.lua:
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 1 | local template = require 'template'
 2 | 
 3 | newaction {
 4 |     trigger = 'template',
 5 |     description = 'generate a template event handler',
 6 |     execute = function()
 7 |         if _OPTIONS['configuration'] == nil then
 8 |             template('configuration.json')
 9 |         else
10 |             template(_OPTIONS['configuration'])
11 |         end
12 |     end
13 | }
14 | newoption {
15 |     trigger = 'configuration',
16 |     value = '/path/to/configuration.json',
17 |     description = 'set the path to the configuration file for template generation'
18 | }
19 | 
20 | solution 'tarsier'
21 |     configurations {'release', 'debug'}
22 |     location 'build'
23 |     project 'tarsier'
24 |         kind 'ConsoleApp'
25 |         language 'C++'
26 |         location 'build'
27 |         files {'source/*.hpp', 'test/*.cpp'}
28 |         configuration 'release'
29 |             targetdir 'build/release'
30 |             defines {'NDEBUG'}
31 |             flags {'OptimizeSpeed'}
32 |         configuration 'debug'
33 |             targetdir 'build/debug'
34 |             defines {'DEBUG'}
35 |             flags {'Symbols'}
36 |         configuration 'linux'
37 |             links {'pthread'}
38 |             buildoptions {'-std=c++11'}
39 |             linkoptions {'-std=c++11'}
40 |         configuration 'macosx'
41 |             buildoptions {'-std=c++11'}
42 |             linkoptions {'-std=c++11'}
43 |         configuration 'windows'
44 |             files {'.clang-format'}
45 | 


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/.travis.yml:
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 1 | language: cpp
 2 | 
 3 | matrix:
 4 |     include:
 5 |         - os: linux
 6 |           dist: trusty
 7 |           compiler: gcc
 8 |           sudo: required
 9 |         - os: osx
10 |           osx_image: xcode9.3
11 |           compiler: gcc
12 |         - os: osx
13 |           osx_image: xcode9.3
14 |           compiler: clang
15 | 
16 | before_install:
17 |     - |
18 |         if [ "$TRAVIS_OS_NAME" = 'osx' ]; then
19 |             brew update
20 |             brew install premake
21 |             brew install clang-format
22 |         fi
23 |     - |
24 |         if [ "$TRAVIS_OS_NAME" = 'linux' ]; then
25 |             sudo apt-get -qq update -y
26 |             sudo apt-get install premake4 -y
27 |             sudo apt-get install clang-format -y
28 |             sudo ln -s /usr/bin/make /usr/bin/gmake
29 |         fi
30 | 
31 | script:
32 |     - |
33 |         for filename in source/*.hpp test/*.cpp; do
34 |             formatted_filename="$(dirname $filename)/formatted_$(basename $filename)"
35 |             clang-format $filename > $formatted_filename
36 |             if [ "$(diff $filename $formatted_filename)" != '' ]; then
37 |                 printf "'$filename' is not properly formatted, run \`clang-format -i $filename\`\n"
38 |                 printf "$(diff $filename $formatted_filename)\n"
39 |             fi
40 |             rm $formatted_filename
41 |         done
42 |     - premake4 gmake || travis_terminate 1
43 |     - cd build || travis_terminate 1
44 |     - make || travis_terminate 1
45 |     - release/tarsier
46 | 


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/source/shift_x.hpp:
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 1 | #pragma once
 2 | 
 3 | #include <cstdint>
 4 | #include <utility>
 5 | 
 6 | /// tarsier is a collection of event handlers.
 7 | namespace tarsier {
 8 | 
 9 |     /// shift_x translates the x coordinate.
10 |     template <typename Event, typename HandleEvent>
11 |     class shift_x {
12 |         public:
13 |         shift_x(uint16_t width, int32_t shift, HandleEvent&& handle_event) :
14 |             _width(width),
15 |             _shift(shift),
16 |             _handle_event(std::forward<HandleEvent>(handle_event)) {}
17 |         shift_x(const shift_x&) = delete;
18 |         shift_x(shift_x&&) = default;
19 |         shift_x& operator=(const shift_x&) = delete;
20 |         shift_x& operator=(shift_x&&) = default;
21 |         virtual ~shift_x() = default;
22 | 
23 |         /// operator() handles an event.
24 |         virtual void operator()(Event event) {
25 |             const auto shifted = static_cast<int32_t>(event.x) + _shift;
26 |             if (shifted >= 0 && shifted < _width) {
27 |                 event.x = shifted;
28 |                 _handle_event(event);
29 |             }
30 |         }
31 | 
32 |         protected:
33 |         const uint16_t _width;
34 |         const int32_t _shift;
35 |         HandleEvent _handle_event;
36 |     };
37 | 
38 |     /// make_shift_x creates a shift_x from a functor.
39 |     template <typename Event, typename HandleEvent>
40 |     inline shift_x<Event, HandleEvent> make_shift_x(uint16_t width, int32_t shift, HandleEvent&& handle_event) {
41 |         return shift_x<Event, HandleEvent>(width, shift, std::forward<HandleEvent>(handle_event));
42 |     }
43 | }
44 | 


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/source/shift_y.hpp:
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 1 | #pragma once
 2 | 
 3 | #include <cstdint>
 4 | #include <utility>
 5 | 
 6 | /// tarsier is a collection of event handlers.
 7 | namespace tarsier {
 8 | 
 9 |     /// shift_y translates the x coordinate.
10 |     template <typename Event, typename HandleEvent>
11 |     class shift_y {
12 |         public:
13 |         shift_y(uint16_t height, int32_t shift, HandleEvent&& handle_event) :
14 |             _height(height),
15 |             _shift(shift),
16 |             _handle_event(std::forward<HandleEvent>(handle_event)) {}
17 |         shift_y(const shift_y&) = delete;
18 |         shift_y(shift_y&&) = default;
19 |         shift_y& operator=(const shift_y&) = delete;
20 |         shift_y& operator=(shift_y&&) = default;
21 |         virtual ~shift_y() = default;
22 | 
23 |         /// operator() handles an event.
24 |         virtual void operator()(Event event) {
25 |             const auto shifted = static_cast<int32_t>(event.y) + _shift;
26 |             if (shifted >= 0 && shifted < _height) {
27 |                 event.y = shifted;
28 |                 _handle_event(event);
29 |             }
30 |         }
31 | 
32 |         protected:
33 |         const uint16_t _height;
34 |         const int32_t _shift;
35 |         HandleEvent _handle_event;
36 |     };
37 | 
38 |     /// make_shift_y creates a shift_y from a functor.
39 |     template <typename Event, typename HandleEvent>
40 |     inline shift_y<Event, HandleEvent> make_shift_y(uint16_t height, int32_t shift, HandleEvent&& handle_event) {
41 |         return shift_y<Event, HandleEvent>(height, shift, std::forward<HandleEvent>(handle_event));
42 |     }
43 | }
44 | 


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/source/select_disk.hpp:
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 1 | #pragma once
 2 | 
 3 | #include <utility>
 4 | 
 5 | /// tarsier is a collection of event handlers.
 6 | namespace tarsier {
 7 |     /// select_disk propagates only the events within the given disk.
 8 |     template <typename Event, typename HandleEvent>
 9 |     class select_disk {
10 |         public:
11 |         select_disk(float x, float y, float radius, HandleEvent&& handle_event) :
12 |             _x(x),
13 |             _y(y),
14 |             _squared_radius(radius * radius),
15 |             _handle_event(std::forward<HandleEvent>(handle_event)) {}
16 |         select_disk(const select_disk&) = delete;
17 |         select_disk(select_disk&&) = default;
18 |         select_disk& operator=(const select_disk&) = delete;
19 |         select_disk& operator=(select_disk&&) = default;
20 |         virtual ~select_disk() = default;
21 | 
22 |         /// operator() handles an event.
23 |         virtual void operator()(Event event) {
24 |             const auto x_delta = event.x - _x;
25 |             const auto y_delta = event.y - _y;
26 |             if (x_delta * x_delta + y_delta * y_delta < _squared_radius) {
27 |                 _handle_event(event);
28 |             }
29 |         }
30 | 
31 |         protected:
32 |         const float _x;
33 |         const float _y;
34 |         const float _squared_radius;
35 |         HandleEvent _handle_event;
36 |     };
37 | 
38 |     /// make_select_disk creates a select_disk from a functor.
39 |     template <typename Event, typename HandleEvent>
40 |     inline select_disk<Event, HandleEvent>
41 |     make_select_disk(float x, float y, float radius, HandleEvent&& handle_event) {
42 |         return select_disk<Event, HandleEvent>(x, y, radius, std::forward<HandleEvent>(handle_event));
43 |     }
44 | }
45 | 


--------------------------------------------------------------------------------
/test/track_blob.cpp:
--------------------------------------------------------------------------------
 1 | #include "../source/track_blob.hpp"
 2 | #include "../third_party/Catch2/single_include/catch.hpp"
 3 | 
 4 | struct event {
 5 |     uint16_t x;
 6 |     uint16_t y;
 7 | };
 8 | 
 9 | struct blob {
10 |     float x;
11 |     float y;
12 |     float sigma_x_squared;
13 |     float sigma_xy;
14 |     float sigma_y_squared;
15 | };
16 | 
17 | TEST_CASE("Average the events with a Gaussian blob", "[track_blob]") {
18 |     blob expected_blob{0.2f, 0.1f, 50.0f, 30.0f, 10.0f};
19 |     auto first_received = false;
20 |     auto track_blob = tarsier::make_track_blob<event, blob>(
21 |         0.0f,
22 |         0.0f,
23 |         10.0f,
24 |         10.0f,
25 |         0.0f,
26 |         0.999f,
27 |         0.999f,
28 |         [](event event, float x, float y, float sigma_x_squared, float sigma_xy, float sigma_y_squared) -> blob {
29 |             return {x, y, sigma_x_squared, sigma_xy, sigma_y_squared};
30 |         },
31 |         [&](blob blob) -> void {
32 |             if (first_received) {
33 |                 REQUIRE(std::abs(blob.x - expected_blob.x) / expected_blob.x < 1e-3f);
34 |                 REQUIRE(std::abs(blob.y - expected_blob.y) / expected_blob.y < 1e-3f);
35 |                 REQUIRE(
36 |                     std::abs(blob.sigma_x_squared - expected_blob.sigma_x_squared) / expected_blob.sigma_x_squared
37 |                     < 1e-3);
38 |                 REQUIRE(std::abs(blob.sigma_xy - expected_blob.sigma_xy) / expected_blob.sigma_xy < 1e-3f);
39 |                 REQUIRE(
40 |                     std::abs(blob.sigma_y_squared - expected_blob.sigma_y_squared) / expected_blob.sigma_y_squared
41 |                     < 1e-3f);
42 |             } else {
43 |                 first_received = true;
44 |             }
45 |         });
46 |     track_blob(event{0, 0});
47 |     track_blob(event{200, 100});
48 | }
49 | 


--------------------------------------------------------------------------------
/source/convert.hpp:
--------------------------------------------------------------------------------
 1 | #pragma once
 2 | 
 3 | #include <utility>
 4 | 
 5 | /// tarsier is a collection of event handlers.
 6 | namespace tarsier {
 7 | 
 8 |     /// convert maps a type to another.
 9 |     template <typename Event, typename EventToConvertedEvent, typename HandleConvertedEvent>
10 |     class convert {
11 |         public:
12 |         convert(EventToConvertedEvent&& event_to_converted_event, HandleConvertedEvent&& handle_converted_event) :
13 |             _event_to_converted_event(std::forward<EventToConvertedEvent>(event_to_converted_event)),
14 |             _handle_converted_event(std::forward<HandleConvertedEvent>(handle_converted_event)) {}
15 |         convert(const convert&) = delete;
16 |         convert(convert&&) = default;
17 |         convert& operator=(const convert&) = delete;
18 |         convert& operator=(convert&&) = default;
19 |         virtual ~convert() = default;
20 | 
21 |         /// operator() handles an event.
22 |         virtual void operator()(Event event) {
23 |             _handle_converted_event(_event_to_converted_event(event));
24 |         }
25 | 
26 |         protected:
27 |         EventToConvertedEvent _event_to_converted_event;
28 |         HandleConvertedEvent _handle_converted_event;
29 |     };
30 | 
31 |     /// make_convert creates a convert from functors.
32 |     template <typename Event, typename EventToConvertedEvent, typename HandleConvertedEvent>
33 |     inline convert<Event, EventToConvertedEvent, HandleConvertedEvent>
34 |     make_convert(EventToConvertedEvent&& event_to_converted_event, HandleConvertedEvent&& handle_converted_event) {
35 |         return convert<Event, EventToConvertedEvent, HandleConvertedEvent>(
36 |             std::forward<EventToConvertedEvent>(event_to_converted_event),
37 |             std::forward<HandleConvertedEvent>(handle_converted_event));
38 |     }
39 | }
40 | 


--------------------------------------------------------------------------------
/test/compute_flow.cpp:
--------------------------------------------------------------------------------
 1 | #include "../source/compute_flow.hpp"
 2 | #include "../third_party/Catch2/single_include/catch.hpp"
 3 | 
 4 | struct event {
 5 |     uint64_t t;
 6 |     uint16_t x;
 7 |     uint16_t y;
 8 | };
 9 | 
10 | struct flow {
11 |     uint64_t t;
12 |     uint16_t x;
13 |     uint16_t y;
14 |     float vx;
15 |     float vy;
16 | };
17 | 
18 | TEST_CASE("Compute the optical flow from the given events", "[compute_flow]") {
19 |     flow expected_flow{
20 |         2010000,
21 |         100,
22 |         100,
23 |         0.0000904721018f,
24 |         0.000232017177f,
25 |     };
26 |     auto flow_generated = false;
27 |     auto compute_flow = tarsier::make_compute_flow<event, flow>(
28 |         320,
29 |         240,
30 |         2,
31 |         1000000,
32 |         10,
33 |         [](event event, float vx, float vy) -> flow {
34 |             return {event.t, event.x, event.y, vx, vy};
35 |         },
36 |         [&](flow flow) -> void {
37 |             flow_generated = true;
38 |             REQUIRE(flow.t == expected_flow.t);
39 |             REQUIRE(flow.x == expected_flow.x);
40 |             REQUIRE(flow.y == expected_flow.y);
41 |             REQUIRE(std::abs(flow.vx - expected_flow.vx) / expected_flow.vx < 1e-3f);
42 |             REQUIRE(std::abs(flow.vy - expected_flow.vy) / expected_flow.vy < 1e-3f);
43 |         });
44 |     compute_flow(event{2000000, 100 - 2, 100 - 2});
45 |     compute_flow(event{2001000, 100 - 1, 100 - 2});
46 |     compute_flow(event{2002000, 100 - 0, 100 - 2});
47 |     compute_flow(event{2003000, 100 - 2, 100 - 1});
48 |     compute_flow(event{2004000, 100 + 1, 100 - 2});
49 |     compute_flow(event{2005000, 100 - 1, 100 - 1});
50 |     compute_flow(event{2006000, 100 - 0, 100 - 1});
51 |     compute_flow(event{2007000, 100 - 2, 100 - 0});
52 |     compute_flow(event{2008000, 100 + 1, 100 - 1});
53 |     compute_flow(event{2010000, 100, 100});
54 |     REQUIRE(flow_generated);
55 | }
56 | 


--------------------------------------------------------------------------------
/source/mask_redundant.hpp:
--------------------------------------------------------------------------------
 1 | #pragma once
 2 | 
 3 | #include <cstdint>
 4 | #include <utility>
 5 | 
 6 | #include <vector>
 7 | 
 8 | /// tarsier is a collection of event handlers.
 9 | namespace tarsier {
10 | 
11 |     /// mask_redundant inverts the x coordinate.
12 |     template <typename Event, typename HandleEvent>
13 |     class mask_redundant {
14 |         public:
15 |         mask_redundant(uint16_t width, uint16_t height, uint64_t duration, HandleEvent handle_event) :
16 |             _width(width),
17 |             _height(height),
18 |             _duration(duration),
19 |             _handle_event(std::forward<HandleEvent>(handle_event)),
20 |             _ts(width * height * 2) {}
21 |         mask_redundant(const mask_redundant&) = delete;
22 |         mask_redundant(mask_redundant&&) = default;
23 |         mask_redundant& operator=(const mask_redundant&) = delete;
24 |         mask_redundant& operator=(mask_redundant&&) = default;
25 |         virtual ~mask_redundant() {}
26 | 
27 |         /// operator() handles an event.
28 |         virtual void operator()(Event event) {
29 |             auto index = (event.x + event.y * _width) * 2 + (event.is_increase ? 1 : 0);
30 |             if (_ts[index] < event.t - _duration) {
31 |                 _ts[index] = event.t;
32 |                 _handle_event(event);
33 |             }
34 |         }
35 | 
36 |         protected:
37 |         const uint16_t _width;
38 |         const uint16_t _height;
39 |         const uint64_t _duration;
40 |         HandleEvent _handle_event;
41 |         std::vector<uint64_t> _ts;
42 |     };
43 | 
44 |     /// make_mask_redundant creates a mask_redundant from a functor.
45 |     template <typename Event, typename HandleEvent>
46 |     mask_redundant<Event, HandleEvent>
47 |     make_mask_redundant(uint16_t width, uint16_t height, uint64_t duration, HandleEvent handle_event) {
48 |         return mask_redundant<Event, HandleEvent>(width, height, duration, std::forward<HandleEvent>(handle_event));
49 |     }
50 | }
51 | 


--------------------------------------------------------------------------------
/source/select_rectangle.hpp:
--------------------------------------------------------------------------------
 1 | #pragma once
 2 | 
 3 | #include <cstdint>
 4 | #include <utility>
 5 | 
 6 | /// tarsier is a collection of event handlers.
 7 | namespace tarsier {
 8 | 
 9 |     /// select_rectangle propagates only the events within the given rectangular
10 |     /// window.
11 |     template <typename Event, typename HandleEvent>
12 |     class select_rectangle {
13 |         public:
14 |         select_rectangle(uint16_t left, uint16_t bottom, uint16_t width, uint16_t height, HandleEvent&& handle_event) :
15 |             _left(left),
16 |             _bottom(bottom),
17 |             _right(left + width),
18 |             _top(bottom + height),
19 |             _handle_event(std::forward<HandleEvent>(handle_event)) {}
20 |         select_rectangle(const select_rectangle&) = delete;
21 |         select_rectangle(select_rectangle&&) = default;
22 |         select_rectangle& operator=(const select_rectangle&) = delete;
23 |         select_rectangle& operator=(select_rectangle&&) = default;
24 |         virtual ~select_rectangle() = default;
25 | 
26 |         /// operator() handles an event.
27 |         virtual void operator()(Event event) {
28 |             if (event.x >= _left && event.x < _right && event.y >= _bottom && event.y < _top) {
29 |                 _handle_event(event);
30 |             }
31 |         }
32 | 
33 |         protected:
34 |         const uint16_t _left;
35 |         const uint16_t _bottom;
36 |         const uint16_t _right;
37 |         const uint16_t _top;
38 |         HandleEvent _handle_event;
39 |     };
40 | 
41 |     /// make_select_rectangle creates a select_rectangle from a functor.
42 |     template <typename Event, typename HandleEvent>
43 |     select_rectangle<Event, HandleEvent> inline make_select_rectangle(
44 |         uint16_t left,
45 |         uint16_t bottom,
46 |         uint16_t width,
47 |         uint16_t height,
48 |         HandleEvent&& handle_event) {
49 |         return select_rectangle<Event, HandleEvent>(
50 |             left, bottom, width, height, std::forward<HandleEvent>(handle_event));
51 |     }
52 | }
53 | 


--------------------------------------------------------------------------------
/source/replicate.hpp:
--------------------------------------------------------------------------------
 1 | #pragma once
 2 | 
 3 | #include <cstdint>
 4 | #include <tuple>
 5 | #include <utility>
 6 | 
 7 | /// tarsier is a collection of event handlers.
 8 | namespace tarsier {
 9 | 
10 |     /// replicate triggers several handlers for each event.
11 |     template <typename Event, typename... HandleEventCallbacks>
12 |     class replicate {
13 |         public:
14 |         replicate(HandleEventCallbacks&&... handle_event_callbacks) :
15 |             _handle_event_callbacks(std::forward<HandleEventCallbacks>(handle_event_callbacks)...) {}
16 |         replicate(const replicate&) = delete;
17 |         replicate(replicate&&) = default;
18 |         replicate& operator=(const replicate&) = delete;
19 |         replicate& operator=(replicate&&) = default;
20 |         virtual ~replicate() = default;
21 | 
22 |         /// operator() handles an event.
23 |         virtual void operator()(Event event) {
24 |             replicate<Event, HandleEventCallbacks...>::trigger<0>(std::forward<Event>(event));
25 |         }
26 | 
27 |         protected:
28 |         /// trigger calls the n-th event callback.
29 |         template <std::size_t index>
30 |             typename std::enable_if < index<sizeof...(HandleEventCallbacks), void>::type trigger(Event event) {
31 |             std::get<index>(_handle_event_callbacks)(event);
32 |             trigger<index + 1>(std::forward<Event>(event));
33 |         }
34 | 
35 |         /// trigger is a termination for the template loop.
36 |         template <std::size_t index>
37 |         typename std::enable_if<index == sizeof...(HandleEventCallbacks), void>::type trigger(Event) {}
38 | 
39 |         std::tuple<HandleEventCallbacks...> _handle_event_callbacks;
40 |     };
41 | 
42 |     /// make_replicate creates a replicate from functors.
43 |     template <typename Event, typename... HandleEventCallbacks>
44 |     inline replicate<Event, HandleEventCallbacks...> make_replicate(HandleEventCallbacks&&... handle_event_callbacks) {
45 |         return replicate<Event, HandleEventCallbacks...>(std::forward<HandleEventCallbacks>(handle_event_callbacks)...);
46 |     }
47 | }
48 | 


--------------------------------------------------------------------------------
/test/average_grid.cpp:
--------------------------------------------------------------------------------
 1 | #include "../source/average_grid.hpp"
 2 | #include "../third_party/Catch2/single_include/catch.hpp"
 3 | #include <vector>
 4 | 
 5 | struct event {
 6 |     uint16_t x;
 7 |     uint16_t y;
 8 | };
 9 | 
10 | struct Position {
11 |     float cx;
12 |     float cy;
13 |     bool valid;
14 | };
15 | 
16 | typedef std::vector<std::vector<Position>> Grid;
17 | 
18 | struct Centroids {
19 |     std::vector<std::vector<Position>> grid;
20 |     uint16_t ir;
21 |     uint16_t ic;
22 | };
23 | 
24 | 
25 | Grid grid = {{{1, 1, true}, {4, 1, true}, {7, 1, true}},
26 |              {{1, 4, true}, {4, 4, true}, {7, 4, true}},
27 |              {{1, 7, true}, {4, 7, true}, {7, 7, false}}};
28 | 
29 | TEST_CASE("Average the position of the given events in a grid", "[average_grid]") {
30 |     auto first_received = false;
31 |     auto second_received = false;
32 |     auto third_received = false;
33 |     auto average_grid = tarsier::make_average_grid<event, Grid>(
34 |         grid,
35 |         3.0,
36 |         0.5,
37 |         [](event event, Grid grid, uint16_t ir, uint16_t ic) -> Centroids {
38 |             return {grid, ir, ic};
39 |         },
40 |         [&](Centroids centroids) -> void {
41 |             if (third_received) {
42 |                 REQUIRE(centroids.grid[centroids.ir][centroids.ic].cx == 7);
43 |                 REQUIRE(centroids.grid[centroids.ir][centroids.ic].cy == 7);
44 |             } else if (second_received) {
45 |                 REQUIRE(centroids.grid[centroids.ir][centroids.ic].cx == 4.5);
46 |                 REQUIRE(centroids.grid[centroids.ir][centroids.ic].cy == 1.5);
47 |                 third_received = true;
48 |             } else if (first_received) {
49 |                 REQUIRE(centroids.grid[centroids.ir][centroids.ic].cx == 1.25);
50 |                 REQUIRE(centroids.grid[centroids.ir][centroids.ic].cy == 1.25);
51 |                 second_received = true;
52 |             } else {
53 |                 first_received = true;
54 |             }
55 |         });
56 |     average_grid(event{0, 0});
57 |     average_grid(event{2, 2});
58 |     average_grid(event{5, 2});
59 |     average_grid(event{8, 8});
60 | }
61 | 


--------------------------------------------------------------------------------
/source/mask_isolated.hpp:
--------------------------------------------------------------------------------
 1 | #pragma once
 2 | 
 3 | #include <cstdint>
 4 | #include <utility>
 5 | #include <vector>
 6 | 
 7 | /// tarsier is a collection of event handlers.
 8 | namespace tarsier {
 9 | 
10 |     /// mask_isolated propagates only events that are not isolated spatially or
11 |     /// temporally.
12 |     template <typename Event, typename HandleEvent>
13 |     class mask_isolated {
14 |         public:
15 |         mask_isolated(uint16_t width, uint16_t height, uint64_t temporal_window, HandleEvent&& handle_event) :
16 |             _width(width),
17 |             _height(height),
18 |             _temporal_window(temporal_window),
19 |             _handle_event(std::forward<HandleEvent>(handle_event)),
20 |             _ts(width * height, 0) {}
21 |         mask_isolated(const mask_isolated&) = delete;
22 |         mask_isolated(mask_isolated&&) = default;
23 |         mask_isolated& operator=(const mask_isolated&) = delete;
24 |         mask_isolated& operator=(mask_isolated&&) = default;
25 |         virtual ~mask_isolated() = default;
26 | 
27 |         /// operator() handles an event.
28 |         virtual void operator()(Event event) {
29 |             const auto index = event.x + event.y * _width;
30 |             _ts[index] = event.t + _temporal_window;
31 |             if ((event.x > 0 && _ts[index - 1] > event.t) || (event.x < _width - 1 && _ts[index + 1] > event.t)
32 |                 || (event.y > 0 && _ts[index - _width] > event.t)
33 |                 || (event.y < _height - 1 && _ts[index + _width] > event.t)) {
34 |                 _handle_event(event);
35 |             }
36 |         }
37 | 
38 |         protected:
39 |         const uint16_t _width;
40 |         const uint16_t _height;
41 |         const uint64_t _temporal_window;
42 |         HandleEvent _handle_event;
43 |         std::vector<uint64_t> _ts;
44 |     };
45 | 
46 |     /// make_mask_isolated creates a mask_isolated from a functor.
47 |     template <typename Event, typename HandleEvent>
48 |     inline mask_isolated<Event, HandleEvent>
49 |     make_mask_isolated(uint16_t width, uint16_t height, uint64_t temporal_window, HandleEvent&& handle_event) {
50 |         return mask_isolated<Event, HandleEvent>(
51 |             width, height, temporal_window, std::forward<HandleEvent>(handle_event));
52 |     }
53 | }
54 | 


--------------------------------------------------------------------------------
/README.md:
--------------------------------------------------------------------------------
 1 | ![banner](banner.png)
 2 | 
 3 | Tarsier is a collection of tools to build event-based algorithms. It is an header-only library.
 4 | 
 5 | # install
 6 | 
 7 | Within a Git repository, run the commands:
 8 | 
 9 | ```sh
10 | mkdir -p third_party
11 | cd third_party
12 | git submodule add https://github.com/neuromorphic-paris/tarsier.git
13 | git submodule update --init --recursive
14 | ```
15 | 
16 | # user guides and documentation
17 | 
18 | User guides and code documentation are held in the [wiki](https://github.com/neuromorphic-paris/tarsier/wiki).
19 | 
20 | # contribute
21 | 
22 | ## development dependencies
23 | 
24 | ### Debian / Ubuntu
25 | 
26 | Open a terminal and run:
27 | ```sh
28 | sudo apt install premake4 # cross-platform build configuration
29 | sudo apt install clang-format # formatting tool
30 | ```
31 | 
32 | ### macOS
33 | 
34 | Open a terminal and run:
35 | ```sh
36 | brew install premake # cross-platform build configuration
37 | brew install clang-format # formatting tool
38 | ```
39 | If the command is not found, you need to install Homebrew first with the command:
40 | ```sh
41 | ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
42 | ```
43 | 
44 | ### Windows
45 | 
46 | Download and install:
47 | - [Visual Studio Community](https://visualstudio.microsoft.com/vs/community/). Select at least __Desktop development with C++__ when asked.
48 | - [git](https://git-scm.com)
49 | - [premake 4.x](https://premake.github.io/download.html). In order to use it from the command line, the *premake4.exe* executable must be copied to a directory in your path. After downloading and decompressing *premake-4.4-beta5-windows.zip*, run in the command prompt:
50 | ```sh
51 | copy "%userprofile%\Downloads\premake-4.4-beta5-windows\premake4.exe" "%userprofile%\AppData\Local\Microsoft\WindowsApps"
52 | ```
53 | 
54 | ## test
55 | 
56 | To test the library, run from the *tarsier* directory:
57 | ```sh
58 | premake4 gmake
59 | cd build
60 | make
61 | cd release
62 | ./tarsier
63 | ```
64 | 
65 | __Windows__ users must run `premake4 vs2010` instead, and open the generated solution with Visual Studio.
66 | 
67 | After changing the code, format the source files by running from the *tarsier* directory:
68 | ```sh
69 | for file in source/*.hpp; do clang-format -i $file; done;
70 | for file in test/*.cpp; do clang-format -i $file; done;
71 | ```
72 | 
73 | __Windows__ users must run *Edit* > *Advanced* > *Format Document* from the Visual Studio menu instead.
74 | 
75 | # license
76 | 
77 | See the [LICENSE](LICENSE.txt) file for license rights and limitations (GNU GPLv3).
78 | 


--------------------------------------------------------------------------------
/source/average_position.hpp:
--------------------------------------------------------------------------------
 1 | #pragma once
 2 | 
 3 | #include <stdexcept>
 4 | #include <utility>
 5 | 
 6 | /// tarsier is a collection of event handlers.
 7 | namespace tarsier {
 8 |     /// average_position calculates the average position of the given events.
 9 |     /// An exponential event-wise decay is used as weight.
10 |     template <typename Event, typename Position, typename EventToPosition, typename HandlePosition>
11 |     class average_position {
12 |         public:
13 |         average_position(
14 |             float x,
15 |             float y,
16 |             float inertia,
17 |             EventToPosition&& event_to_position,
18 |             HandlePosition&& handle_position) :
19 |             _x(x),
20 |             _y(y),
21 |             _inertia(inertia),
22 |             _event_to_position(std::forward<EventToPosition>(event_to_position)),
23 |             _handle_position(std::forward<HandlePosition>(handle_position)) {
24 |             if (_inertia < 0 || _inertia > 1) {
25 |                 throw std::logic_error("inertia must be in the range [0, 1]");
26 |             }
27 |         }
28 |         average_position(const average_position&) = delete;
29 |         average_position(average_position&&) = default;
30 |         average_position& operator=(const average_position&) = delete;
31 |         average_position& operator=(average_position&&) = default;
32 |         virtual ~average_position() = default;
33 | 
34 |         /// operator() handles an event.
35 |         virtual void operator()(Event event) {
36 |             _x = _inertia * _x + (1 - _inertia) * event.x;
37 |             _y = _inertia * _y + (1 - _inertia) * event.y;
38 |             _handle_position(_event_to_position(event, _x, _y));
39 |         }
40 | 
41 |         protected:
42 |         float _x;
43 |         float _y;
44 |         const float _inertia;
45 |         EventToPosition _event_to_position;
46 |         HandlePosition _handle_position;
47 |     };
48 | 
49 |     /// make_average_position creates an average_position from functors.
50 |     template <typename Event, typename Position, typename EventToPosition, typename HandlePosition>
51 |     inline average_position<Event, Position, EventToPosition, HandlePosition> make_average_position(
52 |         float x,
53 |         float y,
54 |         float inertia,
55 |         EventToPosition&& EventToposition,
56 |         HandlePosition&& handle_position) {
57 |         return average_position<Event, Position, EventToPosition, HandlePosition>(
58 |             x,
59 |             y,
60 |             inertia,
61 |             std::forward<EventToPosition>(EventToposition),
62 |             std::forward<HandlePosition>(handle_position));
63 |     }
64 | }
65 | 


--------------------------------------------------------------------------------
/source/average_grid.hpp:
--------------------------------------------------------------------------------
 1 | #pragma once
 2 | 
 3 | #include <stdexcept>
 4 | #include <utility>
 5 | #include <vector>
 6 | #include <cmath>
 7 | 
 8 | /// tarsier is a collection of event handlers.
 9 | namespace tarsier {
10 |     /// average_grid calculates the average positions of the given events within each grid.
11 |     /// An exponential event-wise decay is used as weight.
12 |     template <typename Event, typename Grid, typename EventToGrid, typename HandleGrid>
13 |     class average_grid {
14 |         public:
15 |         average_grid(
16 |             Grid grid,
17 |             float pitch,
18 |             float inertia,
19 |             EventToGrid&& event_to_grid,
20 |             HandleGrid&& handle_grid) :
21 |             _grid(grid),
22 |             _pitch(pitch),
23 |             _inertia(inertia),
24 |             _event_to_grid(std::forward<EventToGrid>(event_to_grid)),
25 |             _handle_grid(std::forward<HandleGrid>(handle_grid)) {
26 |             if (_inertia < 0 || _inertia > 1) {
27 |                 throw std::logic_error("inertia must be in the range [0, 1]");
28 |             }
29 |         }
30 |         average_grid(const average_grid&) = delete;
31 |         average_grid(average_grid&&) = default;
32 |         average_grid& operator=(const average_grid&) = delete;
33 |         average_grid& operator=(average_grid&&) = default;
34 |         virtual ~average_grid() {}
35 | 
36 |         /// operator() handles an event.
37 |         virtual void operator()(Event event) {
38 |             const uint16_t ic = std::floor(event.x / _pitch);
39 |             const uint16_t ir = std::floor(event.y / _pitch);
40 |             if (_grid[ir][ic].valid) {
41 |                 _grid[ir][ic].cx = _inertia * _grid[ir][ic].cx + (1 - _inertia) * event.x;
42 |                 _grid[ir][ic].cy = _inertia * _grid[ir][ic].cy + (1 - _inertia) * event.y;
43 |             }
44 |             _handle_grid(_event_to_grid(event, _grid, ir, ic));
45 |         }
46 | 
47 |         protected:
48 |         Grid _grid;
49 |         const float _pitch;
50 |         const float _inertia;
51 |         EventToGrid _event_to_grid;
52 |         HandleGrid _handle_grid;
53 |     };
54 | 
55 |     /// make_average_grid creates an average_grid from functors.
56 |     template <typename Event, typename Grid, typename EventToGrid, typename HandleGrid>
57 |     inline average_grid<Event, Grid, EventToGrid, HandleGrid> make_average_grid(
58 |         Grid grid,
59 |         float pitch,
60 |         float inertia,
61 |         EventToGrid&& event_to_grid,
62 |         HandleGrid&& handle_grid) {
63 |         return average_grid<Event, Grid, EventToGrid, HandleGrid>(
64 |             grid,
65 |             pitch,
66 |             inertia,
67 |             std::forward<EventToGrid>(event_to_grid),
68 |             std::forward<HandleGrid>(handle_grid));
69 |     }
70 | }
71 | 


--------------------------------------------------------------------------------
/source/compute_activity.hpp:
--------------------------------------------------------------------------------
 1 | #pragma once
 2 | 
 3 | #include <cmath>
 4 | #include <cstdint>
 5 | #include <utility>
 6 | #include <vector>
 7 | 
 8 | /// tarsier is a collection of event handlers.
 9 | namespace tarsier {
10 |     /// compute_activity evaluates the activity at each pixel, using an exponential
11 |     /// decay.
12 |     template <typename Event, typename Activity, typename EventToActivity, typename HandleActivity>
13 |     class compute_activity {
14 |         public:
15 |         compute_activity(
16 |             uint16_t width,
17 |             uint16_t height,
18 |             float decay,
19 |             EventToActivity&& event_to_activity,
20 |             HandleActivity&& handle_activity) :
21 |             _width(width),
22 |             _decay(decay),
23 |             _event_to_activity(std::forward<EventToActivity>(event_to_activity)),
24 |             _handle_activity(std::forward<HandleActivity>(handle_activity)),
25 |             _potentials_and_ts(width * height, {0.0f, 0}) {}
26 |         compute_activity(const compute_activity&) = delete;
27 |         compute_activity(compute_activity&&) = default;
28 |         compute_activity& operator=(const compute_activity&) = delete;
29 |         compute_activity& operator=(compute_activity&&) = default;
30 |         virtual ~compute_activity() = default;
31 | 
32 |         /// operator() handles an event.
33 |         virtual void operator()(Event event) {
34 |             auto& potential_and_t = _potentials_and_ts[event.x + event.y * _width];
35 |             potential_and_t.first =
36 |                 potential_and_t.first * std::exp(-static_cast<float>(event.t - potential_and_t.second) / _decay) + 1;
37 |             potential_and_t.second = event.t;
38 |             _handle_activity(_event_to_activity(event, potential_and_t.first));
39 |         }
40 | 
41 |         protected:
42 |         const uint16_t _width;
43 |         const float _decay;
44 |         EventToActivity _event_to_activity;
45 |         HandleActivity _handle_activity;
46 |         std::vector<std::pair<float, uint64_t>> _potentials_and_ts;
47 |     };
48 | 
49 |     /// make_compute_activity creates a compute_activity from functors.
50 |     template <typename Event, typename Activity, typename EventToActivity, typename HandleActivity>
51 |     inline compute_activity<Event, Activity, EventToActivity, HandleActivity> make_compute_activity(
52 |         uint16_t width,
53 |         uint16_t height,
54 |         float decay,
55 |         EventToActivity&& event_to_activity,
56 |         HandleActivity&& handle_activity) {
57 |         return compute_activity<Event, Activity, EventToActivity, HandleActivity>(
58 |             width,
59 |             height,
60 |             decay,
61 |             std::forward<EventToActivity>(event_to_activity),
62 |             std::forward<HandleActivity>(handle_activity));
63 |     }
64 | }
65 | 


--------------------------------------------------------------------------------
/source/stitch.hpp:
--------------------------------------------------------------------------------
 1 | #pragma once
 2 | 
 3 | #include <cstdint>
 4 | #include <utility>
 5 | #include <vector>
 6 | 
 7 | /// tarsier is a collection of event handlers.
 8 | namespace tarsier {
 9 | 
10 |     /// stitch turns a stream of threshold crossings into a stream of time deltas.
11 |     template <typename ThresholdCrossing, typename Event, typename ThresholdCrossingToEvent, typename HandleEvent>
12 |     class stitch {
13 |         public:
14 |         stitch(
15 |             uint16_t width,
16 |             uint16_t height,
17 |             ThresholdCrossingToEvent&& threshold_crossing_to_event,
18 |             HandleEvent&& handle_event) :
19 |             _width(width),
20 |             _height(height),
21 |             _threshold_crossing_to_event(std::forward<ThresholdCrossingToEvent>(threshold_crossing_to_event)),
22 |             _handle_event(std::forward<HandleEvent>(handle_event)),
23 |             _are_triggered_and_ts(width * height, {false, 0}) {}
24 |         stitch(const stitch&) = delete;
25 |         stitch(stitch&&) = default;
26 |         stitch& operator=(const stitch&) = delete;
27 |         stitch& operator=(stitch&&) = default;
28 |         virtual ~stitch() = default;
29 | 
30 |         /// operator() handles a threshold crossing.
31 |         virtual void operator()(ThresholdCrossing threshold_crossing) {
32 |             auto& is_triggered_and_t = _are_triggered_and_ts[threshold_crossing.x + threshold_crossing.y * _width];
33 |             if (!is_triggered_and_t.first) {
34 |                 if (!threshold_crossing.is_second) {
35 |                     is_triggered_and_t.first = true;
36 |                     is_triggered_and_t.second = threshold_crossing.t;
37 |                 }
38 |             } else {
39 |                 if (threshold_crossing.is_second) {
40 |                     is_triggered_and_t.first = false;
41 |                     _handle_event(_threshold_crossing_to_event(
42 |                         threshold_crossing, threshold_crossing.t - is_triggered_and_t.second));
43 |                 } else {
44 |                     is_triggered_and_t.second = threshold_crossing.t;
45 |                 }
46 |             }
47 |         }
48 | 
49 |         protected:
50 |         const uint16_t _width;
51 |         const uint16_t _height;
52 |         ThresholdCrossingToEvent _threshold_crossing_to_event;
53 |         HandleEvent _handle_event;
54 |         std::vector<std::pair<bool, uint64_t>> _are_triggered_and_ts;
55 |     };
56 | 
57 |     /// make_stitch creates a stitch from functors.
58 |     template <typename ThresholdCrossing, typename Event, typename ThresholdCrossingToEvent, typename HandleEvent>
59 |     inline stitch<ThresholdCrossing, Event, ThresholdCrossingToEvent, HandleEvent> make_stitch(
60 |         uint16_t width,
61 |         uint16_t height,
62 |         ThresholdCrossingToEvent&& threshold_crossing_to_event,
63 |         HandleEvent&& handle_event) {
64 |         return stitch<ThresholdCrossing, Event, ThresholdCrossingToEvent, HandleEvent>(
65 |             width,
66 |             height,
67 |             std::forward<ThresholdCrossingToEvent>(threshold_crossing_to_event),
68 |             std::forward<HandleEvent>(handle_event));
69 |     }
70 | }
71 | 


--------------------------------------------------------------------------------
/.clang-format:
--------------------------------------------------------------------------------
  1 | ---
  2 | Language: Cpp
  3 | AccessModifierOffset: 0
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  5 | AlignConsecutiveAssignments: false
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  8 | AlignOperands: true
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 10 | AllowAllParametersOfDeclarationOnNextLine: false
 11 | AllowShortBlocksOnASingleLine: false
 12 | AllowShortCaseLabelsOnASingleLine: false
 13 | AllowShortFunctionsOnASingleLine: Empty
 14 | AllowShortIfStatementsOnASingleLine: false
 15 | AllowShortLoopsOnASingleLine: true
 16 | AlwaysBreakAfterDefinitionReturnType: None
 17 | AlwaysBreakAfterReturnType: None
 18 | AlwaysBreakBeforeMultilineStrings: false
 19 | AlwaysBreakTemplateDeclarations: true
 20 | BinPackArguments: false
 21 | BinPackParameters: false
 22 | BraceWrapping:
 23 |     AfterClass: false
 24 |     AfterControlStatement: false
 25 |     AfterEnum: false
 26 |     AfterFunction: false
 27 |     AfterNamespace: false
 28 |     AfterObjCDeclaration: false
 29 |     AfterStruct: false
 30 |     AfterUnion: false
 31 |     BeforeCatch: false
 32 |     BeforeElse: false
 33 |     IndentBraces: false
 34 |     SplitEmptyFunction: true
 35 |     SplitEmptyRecord: true
 36 |     SplitEmptyNamespace: true
 37 | BreakBeforeBinaryOperators: NonAssignment
 38 | BreakBeforeBraces: Attach
 39 | BreakBeforeInheritanceComma: false
 40 | BreakBeforeTernaryOperators: false
 41 | BreakConstructorInitializersBeforeComma: false
 42 | BreakConstructorInitializers: AfterColon
 43 | BreakAfterJavaFieldAnnotations: false
 44 | BreakStringLiterals: true
 45 | ColumnLimit: 120
 46 | CommentPragmas: '^ IWYU pragma:'
 47 | CompactNamespaces: false
 48 | ConstructorInitializerAllOnOneLineOrOnePerLine: true
 49 | ConstructorInitializerIndentWidth: 4
 50 | ContinuationIndentWidth: 4
 51 | Cpp11BracedListStyle: true
 52 | DerivePointerAlignment: false
 53 | DisableFormat: false
 54 | ExperimentalAutoDetectBinPacking: false
 55 | FixNamespaceComments: false
 56 | ForEachMacros:
 57 |   - foreach
 58 |   - Q_FOREACH
 59 |   - BOOST_FOREACH
 60 | IncludeCategories:
 61 |   - Regex: '^"(llvm|llvm-c|clang|clang-c)/'
 62 |     Priority: 2
 63 |   - Regex: '^(<|"(gtest|gmock|isl|json)/)'
 64 |     Priority: 3
 65 |   - Regex: '.*'
 66 |     Priority: 1
 67 | IncludeIsMainRegex: '(Test)?$'
 68 | IndentCaseLabels: true
 69 | IndentWidth: 4
 70 | IndentWrappedFunctionNames: false
 71 | JavaScriptQuotes: Single
 72 | JavaScriptWrapImports: true
 73 | KeepEmptyLinesAtTheStartOfBlocks: false
 74 | MacroBlockBegin: ''
 75 | MacroBlockEnd: ''
 76 | MaxEmptyLinesToKeep: 1
 77 | NamespaceIndentation: All
 78 | ObjCBlockIndentWidth: 4
 79 | ObjCSpaceAfterProperty: false
 80 | ObjCSpaceBeforeProtocolList: true
 81 | PenaltyBreakAssignment: 2
 82 | PenaltyBreakBeforeFirstCallParameter: 19
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 86 | PenaltyExcessCharacter: 1000000
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 89 | ReflowComments: true
 90 | SortIncludes: true
 91 | SortUsingDeclarations: true
 92 | SpaceAfterCStyleCast: false
 93 | SpaceAfterTemplateKeyword: true
 94 | SpaceBeforeAssignmentOperators: true
 95 | SpaceBeforeParens: ControlStatements
 96 | SpaceInEmptyParentheses: false
 97 | SpacesBeforeTrailingComments: 1
 98 | SpacesInAngles: false
 99 | SpacesInContainerLiterals: false
100 | SpacesInCStyleCastParentheses: false
101 | SpacesInParentheses: false
102 | SpacesInSquareBrackets: false
103 | Standard: Cpp11
104 | TabWidth: 8
105 | UseTab: Never
106 | ...
107 | 


--------------------------------------------------------------------------------
/test/compute_time_surface.cpp:
--------------------------------------------------------------------------------
 1 | #include "../source/compute_time_surface.hpp"
 2 | #include "../third_party/Catch2/single_include/catch.hpp"
 3 | #include <algorithm>
 4 | 
 5 | const uint16_t spatial_window = 2;
 6 | const auto projections_size = (2 * spatial_window + 1) * (2 * spatial_window + 1);
 7 | 
 8 | struct event {
 9 |     uint64_t t;
10 |     uint16_t x;
11 |     uint16_t y;
12 |     bool polarity;
13 | };
14 | 
15 | struct time_surface {
16 |     uint64_t t;
17 |     uint16_t x;
18 |     uint16_t y;
19 |     std::array<float, projections_size> true_projections;
20 |     std::array<float, projections_size> false_projections;
21 | };
22 | 
23 | TEST_CASE("Compute time surfaces from events", "[compute_time_surface]") {
24 |     time_surface expected_time_surface{2010000, 100, 100};
25 |     expected_time_surface.true_projections[2] = 0.00033546262790251185f;
26 |     expected_time_surface.true_projections[3] = 0.0024787521766663585f;
27 |     expected_time_surface.true_projections[7] = 0.018315638888734179f;
28 |     expected_time_surface.true_projections[8] = 0.1353352832366127f;
29 |     expected_time_surface.false_projections[1] = 0.00012340980408667956f;
30 |     expected_time_surface.false_projections[5] = 0.00091188196555451624f;
31 |     expected_time_surface.false_projections[6] = 0.006737946999085467f;
32 |     expected_time_surface.false_projections[10] = 0.049787068367863944f;
33 |     expected_time_surface.false_projections[12] = 1.0f;
34 |     std::size_t count = 0;
35 |     auto compute_time_surface = tarsier::make_compute_time_surface<event, bool, time_surface, spatial_window>(
36 |         320,
37 |         240,
38 |         10000,
39 |         1000,
40 |         [](event event, std::array<std::pair<float, bool>, projections_size> projections_and_polarities) {
41 |             time_surface time_surface{event.t, event.x, event.y};
42 |             for (std::size_t index = 0; index < projections_size; ++index) {
43 |                 if (projections_and_polarities[index].second) {
44 |                     time_surface.true_projections[index] = projections_and_polarities[index].first;
45 |                 } else {
46 |                     time_surface.false_projections[index] = projections_and_polarities[index].first;
47 |                 }
48 |             }
49 |             return time_surface;
50 |         },
51 |         [&](time_surface time_surface) {
52 |             ++count;
53 |             if (count == 10) {
54 |                 REQUIRE(time_surface.x == expected_time_surface.x);
55 |                 REQUIRE(time_surface.y == expected_time_surface.y);
56 |                 REQUIRE(time_surface.t == expected_time_surface.t);
57 |                 for (std::size_t index = 0; index < projections_size; ++index) {
58 |                     REQUIRE(
59 |                         std::abs(time_surface.true_projections[index] - expected_time_surface.true_projections[index])
60 |                         <= 1e-3 * expected_time_surface.true_projections[index]);
61 |                     REQUIRE(
62 |                         std::abs(time_surface.false_projections[index] - expected_time_surface.false_projections[index])
63 |                         <= 1e-3 * expected_time_surface.false_projections[index]);
64 |                 }
65 |             }
66 |         });
67 |     compute_time_surface(event{2000000, 100 - 2, 100 - 2, true});
68 |     compute_time_surface(event{2001000, 100 - 1, 100 - 2, false});
69 |     compute_time_surface(event{2002000, 100 - 0, 100 - 2, true});
70 |     compute_time_surface(event{2003000, 100 - 2, 100 - 1, false});
71 |     compute_time_surface(event{2004000, 100 + 1, 100 - 2, true});
72 |     compute_time_surface(event{2005000, 100 - 1, 100 - 1, false});
73 |     compute_time_surface(event{2006000, 100 - 0, 100 - 1, true});
74 |     compute_time_surface(event{2007000, 100 - 2, 100 - 0, false});
75 |     compute_time_surface(event{2008000, 100 + 1, 100 - 1, true});
76 |     compute_time_surface(event{2010000, 100, 100, false});
77 | }
78 | 


--------------------------------------------------------------------------------
/source/track_blob.hpp:
--------------------------------------------------------------------------------
  1 | #pragma once
  2 | 
  3 | #include <cmath>
  4 | #include <stdexcept>
  5 | #include <utility>
  6 | 
  7 | /// tarsier is a collection of event handlers.
  8 | namespace tarsier {
  9 |     /// track_blob averages the incoming events with a gaussian blob.
 10 |     template <typename Event, typename Blob, typename EventToBlob, typename HandleBlob>
 11 |     class track_blob {
 12 |         public:
 13 |         track_blob(
 14 |             float x,
 15 |             float y,
 16 |             float sigma_x_squared,
 17 |             float sigma_xy,
 18 |             float sigma_y_squared,
 19 |             float position_inertia,
 20 |             float variance_inertia,
 21 |             EventToBlob&& event_to_blob,
 22 |             HandleBlob&& handle_blob) :
 23 |             _x(x),
 24 |             _y(y),
 25 |             _sigma_x_squared(sigma_x_squared),
 26 |             _sigma_xy(sigma_xy),
 27 |             _sigma_y_squared(sigma_y_squared),
 28 |             _position_inertia(position_inertia),
 29 |             _variance_inertia(variance_inertia),
 30 |             _event_to_blob(std::forward<EventToBlob>(event_to_blob)),
 31 |             _handle_blob(std::forward<HandleBlob>(handle_blob)) {
 32 |             if (_position_inertia < 0 || _position_inertia > 1) {
 33 |                 throw std::logic_error("position_inertia must be in the range [0, 1]");
 34 |             }
 35 |             if (_variance_inertia < 0 || _variance_inertia > 1) {
 36 |                 throw std::logic_error("variance_inertia must be in the range [0, 1]");
 37 |             }
 38 |         }
 39 |         track_blob(const track_blob&) = delete;
 40 |         track_blob(track_blob&&) = default;
 41 |         track_blob& operator=(const track_blob&) = delete;
 42 |         track_blob& operator=(track_blob&&) = default;
 43 |         virtual ~track_blob() = default;
 44 | 
 45 |         /// operator() handles an event.
 46 |         virtual void operator()(Event event) {
 47 |             const auto x_delta = event.x - _x;
 48 |             const auto y_delta = event.y - _y;
 49 |             _x = _position_inertia * _x + (1 - _position_inertia) * event.x;
 50 |             _y = _position_inertia * _y + (1 - _position_inertia) * event.y;
 51 |             _sigma_x_squared = _variance_inertia * _sigma_x_squared + (1 - _variance_inertia) * x_delta * x_delta;
 52 |             _sigma_xy = _variance_inertia * _sigma_xy + (1 - _variance_inertia) * x_delta * y_delta;
 53 |             _sigma_y_squared = _variance_inertia * _sigma_y_squared + (1 - _variance_inertia) * y_delta * y_delta;
 54 |             _handle_blob(_event_to_blob(event, _x, _y, _sigma_x_squared, _sigma_xy, _sigma_y_squared));
 55 |         }
 56 | 
 57 |         /// x returns the blob's center's x coordinate.
 58 |         float x() const {
 59 |             return _x;
 60 |         }
 61 | 
 62 |         /// y returns the blob's center's y coordinate.
 63 |         float y() const {
 64 |             return _y;
 65 |         }
 66 | 
 67 |         /// sigma_x_squared returns the blob's variance along the x axis.
 68 |         float sigma_x_squared() const {
 69 |             return _sigma_x_squared;
 70 |         }
 71 | 
 72 |         /// sigma_xy returns the blob's covariance.
 73 |         float sigma_xy() const {
 74 |             return _sigma_xy;
 75 |         }
 76 | 
 77 |         /// sigma_y_squared returns the blob's variance along the y axis.
 78 |         float sigma_y_squared() const {
 79 |             return _sigma_y_squared;
 80 |         }
 81 | 
 82 |         protected:
 83 |         float _x;
 84 |         float _y;
 85 |         float _sigma_x_squared;
 86 |         float _sigma_xy;
 87 |         float _sigma_y_squared;
 88 |         const float _position_inertia;
 89 |         const float _variance_inertia;
 90 |         EventToBlob _event_to_blob;
 91 |         HandleBlob _handle_blob;
 92 |     };
 93 | 
 94 |     /// make_track_blob creates a track_blob from functors.
 95 |     template <typename Event, typename Blob, typename EventToBlob, typename HandleBlob>
 96 |     inline track_blob<Event, Blob, EventToBlob, HandleBlob> make_track_blob(
 97 |         float x,
 98 |         float y,
 99 |         float sigma_x_squared,
100 |         float sigma_xy,
101 |         float sigma_y_squared,
102 |         float position_inertia,
103 |         float variance_inertia,
104 |         EventToBlob&& event_to_blob,
105 |         HandleBlob&& handle_blob) {
106 |         return track_blob<Event, Blob, EventToBlob, HandleBlob>(
107 |             x,
108 |             y,
109 |             sigma_x_squared,
110 |             sigma_xy,
111 |             sigma_y_squared,
112 |             position_inertia,
113 |             variance_inertia,
114 |             std::forward<EventToBlob>(event_to_blob),
115 |             std::forward<HandleBlob>(handle_blob));
116 |     }
117 | }
118 | 


--------------------------------------------------------------------------------
/source/compute_time_surface.hpp:
--------------------------------------------------------------------------------
  1 | #pragma once
  2 | 
  3 | #include <array>
  4 | #include <cmath>
  5 | #include <cstdint>
  6 | #include <utility>
  7 | #include <vector>
  8 | 
  9 | /// tarsier is a collection of event handlers.
 10 | namespace tarsier {
 11 |     /// compute_time_surface extracts time surfaces from events.
 12 |     template <
 13 |         typename Event,
 14 |         typename Polarity,
 15 |         typename TimeSurface,
 16 |         uint16_t spatial_window,
 17 |         typename EventToTimeSurface,
 18 |         typename HandleTimeSurface>
 19 |     class compute_time_surface {
 20 |         public:
 21 |         compute_time_surface(
 22 |             uint16_t width,
 23 |             uint16_t height,
 24 |             uint64_t temporal_window,
 25 |             float decay,
 26 |             EventToTimeSurface&& event_to_time_surface,
 27 |             HandleTimeSurface&& handle_time_surface) :
 28 |             _width(width),
 29 |             _height(height),
 30 |             _temporal_window(temporal_window),
 31 |             _decay(decay),
 32 |             _event_to_time_surface(std::forward<EventToTimeSurface>(event_to_time_surface)),
 33 |             _handle_time_surface(std::forward<HandleTimeSurface>(handle_time_surface)),
 34 |             _ts_and_polarities(width * height, {0, false}) {}
 35 |         compute_time_surface(const compute_time_surface&) = delete;
 36 |         compute_time_surface(compute_time_surface&&) = default;
 37 |         compute_time_surface& operator=(const compute_time_surface&) = delete;
 38 |         compute_time_surface& operator=(compute_time_surface&&) = default;
 39 |         virtual ~compute_time_surface() = default;
 40 | 
 41 |         /// operator() handles an event.
 42 |         virtual void operator()(Event event) {
 43 |             {
 44 |                 const auto index = event.x + event.y * _width;
 45 |                 _ts_and_polarities[index].first = event.t;
 46 |                 _ts_and_polarities[index].second = event.polarity;
 47 |             }
 48 |             const auto t_threshold = (event.t <= _temporal_window ? 0 : event.t - _temporal_window);
 49 |             std::array<std::pair<float, Polarity>, (spatial_window * 2 + 1) * (spatial_window * 2 + 1)>
 50 |                 projections_and_polarities;
 51 |             for (uint16_t y = (event.y <= spatial_window ? 0 : event.y - spatial_window);
 52 |                  y <= (event.y >= _height - 1 - spatial_window ? _height - 1 : event.y + spatial_window);
 53 |                  ++y) {
 54 |                 for (uint16_t x = (event.x <= spatial_window ? 0 : event.x - spatial_window);
 55 |                      x <= (event.x >= _width - 1 - spatial_window ? _width - 1 : event.x + spatial_window);
 56 |                      ++x) {
 57 |                     const auto t_and_polarity = _ts_and_polarities[x + y * _width];
 58 |                     if (t_and_polarity.first > t_threshold) {
 59 |                         projections_and_polarities
 60 |                             [x + spatial_window - event.x + (y + spatial_window - event.y) * (2 * spatial_window + 1)] =
 61 |                                 {std::exp(-static_cast<float>(event.t - t_and_polarity.first) / _decay),
 62 |                                  t_and_polarity.second};
 63 |                     }
 64 |                 }
 65 |             }
 66 |             _handle_time_surface(_event_to_time_surface(event, projections_and_polarities));
 67 |         }
 68 | 
 69 |         protected:
 70 |         const uint16_t _width;
 71 |         const uint16_t _height;
 72 |         const uint64_t _temporal_window;
 73 |         const float _decay;
 74 |         EventToTimeSurface _event_to_time_surface;
 75 |         HandleTimeSurface _handle_time_surface;
 76 |         std::vector<std::pair<uint64_t, Polarity>> _ts_and_polarities;
 77 |     };
 78 | 
 79 |     /// make_compute_time_surface creates a compute_time_surface from functors.
 80 |     template <
 81 |         typename Event,
 82 |         typename Polarity,
 83 |         typename TimeSurface,
 84 |         uint16_t spatial_window,
 85 |         typename EventToTimeSurface,
 86 |         typename HandleTimeSurface>
 87 |     inline compute_time_surface<Event, Polarity, TimeSurface, spatial_window, EventToTimeSurface, HandleTimeSurface>
 88 |     make_compute_time_surface(
 89 |         uint16_t width,
 90 |         uint16_t height,
 91 |         uint64_t temporal_window,
 92 |         float decay,
 93 |         EventToTimeSurface&& event_to_time_surface,
 94 |         HandleTimeSurface&& handle_time_surface) {
 95 |         return compute_time_surface<
 96 |             Event,
 97 |             Polarity,
 98 |             TimeSurface,
 99 |             spatial_window,
100 |             EventToTimeSurface,
101 |             HandleTimeSurface>(
102 |             width,
103 |             height,
104 |             temporal_window,
105 |             decay,
106 |             std::forward<EventToTimeSurface>(event_to_time_surface),
107 |             std::forward<HandleTimeSurface>(handle_time_surface));
108 |     }
109 | }
110 | 


--------------------------------------------------------------------------------
/test/track_blob_multi.cpp:
--------------------------------------------------------------------------------
 1 | #include "../source/track_blob_multi.hpp"
 2 | #include "../third_party/Catch2/single_include/catch.hpp"
 3 | #include <vector>
 4 | struct Event {
 5 |     uint16_t x;
 6 |     uint16_t y;
 7 | };
 8 | 
 9 | struct Blob {
10 |     float x;
11 |     float y;
12 |     float sigma_x_squared;
13 |     float sigma_xy;
14 |     float sigma_y_squared;
15 | };
16 | 
17 | struct MultiBlobs {
18 |     uint16_t id;
19 |     std::vector<Blob> blobs;
20 | };
21 | 
22 | TEST_CASE("Average the events with multiple Gaussian blobs", "[track_blob_multi]") {
23 |     MultiBlobs multi_blobs_initial{0, {{2.0f, 2.0f, 0.16f, 0.0f, 0.16f},
24 |                                        {7.0f, 2.0f, 0.16f, 0.0f, 0.16f}}};
25 |     MultiBlobs expected_multi_blobs_0{0, {{2.5f, 2.5f, 0.58f, 0.5f, 0.58f},
26 |                                           {7.0f, 2.0f, 0.16f, 0.0f, 0.16f}}};
27 |     MultiBlobs expected_multi_blobs_1{1, {{2.5f, 2.5f, 0.58f, 0.5f, 0.58f},
28 |                                           {7.5f, 2.5f, 0.58f, 0.5f, 0.58f}}};
29 | 
30 |     auto first_received = false;
31 |     auto track_blob_multi = tarsier::make_track_blob_multi<Event, MultiBlobs>(
32 |         multi_blobs_initial,
33 |         0.001f,
34 |         0.5f,
35 |         0.5f,
36 |         [](Event event, MultiBlobs multi_blobs) -> MultiBlobs { return {multi_blobs}; },
37 |         [&](MultiBlobs multi_blobs) -> void {
38 |             if (first_received) {
39 |                 REQUIRE(multi_blobs.id == expected_multi_blobs_1.id);
40 | 
41 |                 REQUIRE(std::abs(multi_blobs.blobs[0].x - expected_multi_blobs_1.blobs[0].x) / expected_multi_blobs_1.blobs[0].x < 1e-3f);
42 |                 REQUIRE(std::abs(multi_blobs.blobs[0].y - expected_multi_blobs_1.blobs[0].y) / expected_multi_blobs_1.blobs[0].y < 1e-3f);
43 |                 REQUIRE(std::abs(multi_blobs.blobs[0].sigma_x_squared - expected_multi_blobs_1.blobs[0].sigma_x_squared) / expected_multi_blobs_1.blobs[0].sigma_x_squared < 1e-3f);
44 |                 REQUIRE(std::abs(multi_blobs.blobs[0].sigma_xy - expected_multi_blobs_1.blobs[0].sigma_xy) / (expected_multi_blobs_1.blobs[0].sigma_xy + 1e-3f) < 1e-3f);
45 |                 REQUIRE(std::abs(multi_blobs.blobs[0].sigma_y_squared - expected_multi_blobs_1.blobs[0].sigma_y_squared) / expected_multi_blobs_1.blobs[0].sigma_y_squared < 1e-3f);
46 | 
47 |                 REQUIRE(std::abs(multi_blobs.blobs[1].x - expected_multi_blobs_1.blobs[1].x) / expected_multi_blobs_1.blobs[1].x < 1e-3f);
48 |                 REQUIRE(std::abs(multi_blobs.blobs[1].y - expected_multi_blobs_1.blobs[1].y) / expected_multi_blobs_1.blobs[1].y < 1e-3f);
49 |                 REQUIRE(std::abs(multi_blobs.blobs[1].sigma_x_squared - expected_multi_blobs_1.blobs[1].sigma_x_squared) / expected_multi_blobs_1.blobs[1].sigma_x_squared < 1e-3f);
50 |                 REQUIRE(std::abs(multi_blobs.blobs[1].sigma_xy - expected_multi_blobs_1.blobs[1].sigma_xy) / (expected_multi_blobs_1.blobs[1].sigma_xy + 1e-3f) < 1e-3f);
51 |                 REQUIRE(std::abs(multi_blobs.blobs[1].sigma_y_squared - expected_multi_blobs_1.blobs[1].sigma_y_squared) / expected_multi_blobs_1.blobs[1].sigma_y_squared < 1e-3f);
52 |             } else {
53 |                 REQUIRE(multi_blobs.id == expected_multi_blobs_0.id);
54 | 
55 |                 REQUIRE(std::abs(multi_blobs.blobs[0].x - expected_multi_blobs_0.blobs[0].x) / expected_multi_blobs_0.blobs[0].x < 1e-3f);
56 |                 REQUIRE(std::abs(multi_blobs.blobs[0].y - expected_multi_blobs_0.blobs[0].y) / expected_multi_blobs_0.blobs[0].y < 1e-3f);
57 |                 REQUIRE(std::abs(multi_blobs.blobs[0].sigma_x_squared - expected_multi_blobs_0.blobs[0].sigma_x_squared) / expected_multi_blobs_0.blobs[0].sigma_x_squared < 1e-3f);
58 |                 REQUIRE(std::abs(multi_blobs.blobs[0].sigma_xy - expected_multi_blobs_0.blobs[0].sigma_xy) / (expected_multi_blobs_0.blobs[0].sigma_xy + 1e-3f) < 1e-3f);
59 |                 REQUIRE(std::abs(multi_blobs.blobs[0].sigma_y_squared - expected_multi_blobs_0.blobs[0].sigma_y_squared) / expected_multi_blobs_0.blobs[0].sigma_y_squared < 1e-3f);
60 | 
61 |                 REQUIRE(std::abs(multi_blobs.blobs[1].x - expected_multi_blobs_0.blobs[1].x) / expected_multi_blobs_0.blobs[1].x < 1e-3f);
62 |                 REQUIRE(std::abs(multi_blobs.blobs[1].y - expected_multi_blobs_0.blobs[1].y) / expected_multi_blobs_0.blobs[1].y < 1e-3f);
63 |                 REQUIRE(std::abs(multi_blobs.blobs[1].sigma_x_squared - expected_multi_blobs_0.blobs[1].sigma_x_squared) / expected_multi_blobs_0.blobs[1].sigma_x_squared < 1e-3f);
64 |                 REQUIRE(std::abs(multi_blobs.blobs[1].sigma_xy - expected_multi_blobs_0.blobs[1].sigma_xy) / (expected_multi_blobs_0.blobs[1].sigma_xy + 1e-3f) < 1e-3f);
65 |                 REQUIRE(std::abs(multi_blobs.blobs[1].sigma_y_squared - expected_multi_blobs_0.blobs[1].sigma_y_squared) / expected_multi_blobs_0.blobs[1].sigma_y_squared < 1e-3f);
66 | 
67 |                 first_received = true;
68 |             }
69 |         });
70 |     track_blob_multi(Event{3, 3});
71 |     track_blob_multi(Event{8, 3});
72 | }
73 | 


--------------------------------------------------------------------------------
/source/hash.hpp:
--------------------------------------------------------------------------------
  1 | #pragma once
  2 | 
  3 | #include <cstdint>
  4 | #include <utility>
  5 | 
  6 | /// tarsier is a collection of event handlers.
  7 | namespace tarsier {
  8 |     /// hash calculates the MurmurHash3 (128 bits, x64 version) of the given values.
  9 |     template <typename Uint, typename HandleUint64Pair>
 10 |     class hash {
 11 |         public:
 12 |         hash(HandleUint64Pair&& handle_uint64_pair) :
 13 |             _handle_uint64_pair(std::forward<HandleUint64Pair>(handle_uint64_pair)),
 14 |             _shift(0),
 15 |             _block(0, 0),
 16 |             _hash(0, 0),
 17 |             _size(0) {}
 18 |         hash(const hash&) = delete;
 19 |         hash(hash&&) = default;
 20 |         hash& operator=(const hash&) = delete;
 21 |         hash& operator=(hash&&) = default;
 22 |         virtual ~hash() {
 23 |             if (_size > 0 || _shift > 0) {
 24 |                 if (_shift * sizeof(Uint) > 8) {
 25 |                     std::get<1>(_block) *= 0x4cf5ad432745937full;
 26 |                     std::get<1>(_block) = rotate(std::get<1>(_block), 33);
 27 |                     std::get<1>(_block) *= 0x87c37b91114253d5ull;
 28 |                     std::get<1>(_hash) ^= std::get<1>(_block);
 29 |                 }
 30 |                 if (_shift * sizeof(Uint) > 0) {
 31 |                     std::get<0>(_block) *= 0x87c37b91114253d5ull;
 32 |                     std::get<0>(_block) = rotate(std::get<0>(_block), 31);
 33 |                     std::get<0>(_block) *= 0x4cf5ad432745937full;
 34 |                     std::get<0>(_hash) ^= std::get<0>(_block);
 35 |                 }
 36 |                 std::get<0>(_hash) ^= (_size * 16 + _shift);
 37 |                 std::get<1>(_hash) ^= (_size * 16 + _shift);
 38 |                 std::get<0>(_hash) += std::get<1>(_hash);
 39 |                 std::get<1>(_hash) += std::get<0>(_hash);
 40 |                 std::get<0>(_hash) = mix(std::get<0>(_hash));
 41 |                 std::get<1>(_hash) = mix(std::get<1>(_hash));
 42 |                 std::get<0>(_hash) += std::get<1>(_hash);
 43 |                 std::get<1>(_hash) += std::get<0>(_hash);
 44 |                 _handle_uint64_pair(_hash);
 45 |             }
 46 |         }
 47 | 
 48 |         /// operator() handles an event.
 49 |         virtual void operator()(Uint uint) {
 50 |             if (_shift < 8 / sizeof(Uint)) {
 51 |                 std::get<0>(_block) |= (static_cast<uint64_t>(uint) << (_shift * sizeof(Uint) * 8));
 52 |                 ++_shift;
 53 |             } else {
 54 |                 std::get<1>(_block) |= (static_cast<uint64_t>(uint) << (_shift * sizeof(Uint) * 8 - 64));
 55 |                 if (_shift < 16 / sizeof(Uint) - 1) {
 56 |                     ++_shift;
 57 |                 } else {
 58 |                     _shift = 0;
 59 |                     ++_size;
 60 |                     std::get<0>(_block) *= 0x87c37b91114253d5ull;
 61 |                     std::get<0>(_block) = rotate(std::get<0>(_block), 31);
 62 |                     std::get<0>(_block) *= 0x4cf5ad432745937full;
 63 |                     std::get<0>(_hash) ^= std::get<0>(_block);
 64 |                     std::get<0>(_hash) = rotate(std::get<0>(_hash), 27);
 65 |                     std::get<0>(_hash) += std::get<1>(_hash);
 66 |                     std::get<0>(_hash) = std::get<0>(_hash) * 5 + 0x52dce729;
 67 |                     std::get<1>(_block) *= 0x4cf5ad432745937full;
 68 |                     std::get<1>(_block) = rotate(std::get<1>(_block), 33);
 69 |                     std::get<1>(_block) *= 0x87c37b91114253d5ull;
 70 |                     std::get<1>(_hash) ^= std::get<1>(_block);
 71 |                     std::get<1>(_hash) = rotate(std::get<1>(_hash), 31);
 72 |                     std::get<1>(_hash) += std::get<0>(_hash);
 73 |                     std::get<1>(_hash) = std::get<1>(_hash) * 5 + 0x38495ab5;
 74 |                     std::get<0>(_block) = 0;
 75 |                     std::get<1>(_block) = 0;
 76 |                 }
 77 |             }
 78 |         }
 79 | 
 80 |         protected:
 81 |         /// rotate implements a bit-wise rotation.
 82 |         static uint64_t rotate(uint64_t value, uint8_t range) {
 83 |             return (value << range) | (value >> (64 - range));
 84 |         }
 85 | 
 86 |         /// mix implements a bit-wise mix.
 87 |         static uint64_t mix(uint64_t value) {
 88 |             value ^= value >> 33;
 89 |             value *= 0xff51afd7ed558ccdull;
 90 |             value ^= value >> 33;
 91 |             value *= 0xc4ceb9fe1a85ec53ull;
 92 |             value ^= value >> 33;
 93 |             return value;
 94 |         }
 95 | 
 96 |         HandleUint64Pair _handle_uint64_pair;
 97 |         uint8_t _shift;
 98 |         std::pair<uint64_t, uint64_t> _block;
 99 |         std::pair<uint64_t, uint64_t> _hash;
100 |         uint64_t _size;
101 |     };
102 | 
103 |     /// make_hash creates a hash from functors.
104 |     template <typename Uint, typename HandleUint64Pair>
105 |     inline hash<Uint, HandleUint64Pair> make_hash(HandleUint64Pair&& handle_uint64_pair) {
106 |         return hash<Uint, HandleUint64Pair>(std::forward<HandleUint64Pair>(handle_uint64_pair));
107 |     }
108 | }
109 | 


--------------------------------------------------------------------------------
/source/track_blob_multi.hpp:
--------------------------------------------------------------------------------
  1 | #pragma once
  2 | 
  3 | #include <cmath>
  4 | #include <stdexcept>
  5 | #include <utility>
  6 | #include <vector>
  7 | 
  8 | /// tarsier is a collection of event handlers.
  9 | namespace tarsier {
 10 |     /// track_blob_multi averages the incoming events with a gaussian blob.
 11 |     template <typename Event, typename MultiBlobs, typename EventToBlob, typename HandleBlob>
 12 |     class track_blob_multi {
 13 |         public:
 14 |         track_blob_multi(
 15 |             MultiBlobs multi_blobs,
 16 |             float prob_threshold,
 17 |             float position_inertia,
 18 |             float variance_inertia,
 19 |             EventToBlob&& event_to_blob,
 20 |             HandleBlob&& handle_blob) :
 21 |             _multi_blobs(multi_blobs),
 22 |             _prob_threshold(prob_threshold),
 23 |             _position_inertia(position_inertia),
 24 |             _variance_inertia(variance_inertia),
 25 |             _event_to_blob(std::forward<EventToBlob>(event_to_blob)),
 26 |             _handle_blob(std::forward<HandleBlob>(handle_blob)) {
 27 |             if (_prob_threshold < 0 || _prob_threshold > 1) {
 28 |                 throw std::logic_error("prob_threshold must be in the range [0, 1]");
 29 |             }
 30 |             if (_position_inertia < 0 || _position_inertia > 1) {
 31 |                 throw std::logic_error("position_inertia must be in the range [0, 1]");
 32 |             }
 33 |             if (_variance_inertia < 0 || _variance_inertia > 1) {
 34 |                 throw std::logic_error("variance_inertia must be in the range [0, 1]");
 35 |             }
 36 |         }
 37 |         track_blob_multi(const track_blob_multi&) = delete;
 38 |         track_blob_multi(track_blob_multi&&) = default;
 39 |         track_blob_multi& operator=(const track_blob_multi&) = delete;
 40 |         track_blob_multi& operator=(track_blob_multi&&) = default;
 41 |         virtual ~track_blob_multi() = default;
 42 | 
 43 |         /// operator() handles an event.
 44 |         virtual void operator()(Event event) {
 45 |             uint16_t max_id = 0;
 46 |             float max_prob = 0.0f;
 47 |             // compute probability of each tracker
 48 |             for (uint16_t i = 0; i < _multi_blobs.blobs.size(); i++) {
 49 |                 auto sigma_x_squared = _multi_blobs.blobs[i].sigma_x_squared;
 50 |                 auto sigma_xy = _multi_blobs.blobs[i].sigma_xy;
 51 |                 auto sigma_y_squared = _multi_blobs.blobs[i].sigma_y_squared;
 52 | 
 53 |                 const auto det = sigma_x_squared * sigma_y_squared - sigma_xy * sigma_xy;
 54 |                 const auto x_delta = event.x - _multi_blobs.blobs[i].x;
 55 |                 const auto y_delta = event.y - _multi_blobs.blobs[i].y;
 56 |                 const auto exp_power = -0.5 / det * (x_delta * x_delta * sigma_y_squared +
 57 |                                                      y_delta * y_delta * sigma_x_squared);
 58 |                 float prob = std::pow(det, -0.5) * std::exp(exp_power) / (2 * M_PI);
 59 |                 
 60 |                 if (prob > max_prob) {
 61 |                     max_prob = prob;
 62 |                     max_id = i;
 63 |                 }
 64 |             }
 65 | 
 66 |             // update tracker
 67 |             if (max_prob >= _prob_threshold) {
 68 |                 _multi_blobs.id = max_id;
 69 |                 const auto x_delta = event.x - _multi_blobs.blobs[max_id].x;
 70 |                 const auto y_delta = event.y - _multi_blobs.blobs[max_id].y;
 71 |                 _multi_blobs.blobs[max_id].x = _position_inertia * _multi_blobs.blobs[max_id].x + (1 - _position_inertia) * event.x;
 72 |                 _multi_blobs.blobs[max_id].y = _position_inertia * _multi_blobs.blobs[max_id].y + (1 - _position_inertia) * event.y;
 73 |                 _multi_blobs.blobs[max_id].sigma_x_squared = _variance_inertia * _multi_blobs.blobs[max_id].sigma_x_squared + (1 - _variance_inertia) * x_delta * x_delta;
 74 |                 _multi_blobs.blobs[max_id].sigma_xy = _variance_inertia * _multi_blobs.blobs[max_id].sigma_xy + (1 - _variance_inertia) * x_delta * y_delta;
 75 |                 _multi_blobs.blobs[max_id].sigma_y_squared = _variance_inertia * _multi_blobs.blobs[max_id].sigma_y_squared + (1 - _variance_inertia) * y_delta * y_delta;
 76 |             }
 77 | 
 78 |             // TODO: compute tracker activity
 79 | 
 80 |             _handle_blob(_event_to_blob(event, _multi_blobs));
 81 |         }
 82 | 
 83 |         protected:
 84 |         MultiBlobs _multi_blobs;
 85 |         const float _prob_threshold;
 86 |         const float _position_inertia;
 87 |         const float _variance_inertia;
 88 |         EventToBlob _event_to_blob;
 89 |         HandleBlob _handle_blob;
 90 |     };
 91 | 
 92 |     /// make_track_blob_multi creates a track_blob_multi from functors.
 93 |     template <typename Event, typename MultiBlobs, typename EventToBlob, typename HandleBlob>
 94 |     inline track_blob_multi<Event, MultiBlobs, EventToBlob, HandleBlob> make_track_blob_multi(
 95 |         MultiBlobs multi_blobs,
 96 |         float prob_threshold,
 97 |         float position_inertia,
 98 |         float variance_inertia,
 99 |         EventToBlob&& event_to_blob,
100 |         HandleBlob&& handle_blob) {
101 |         return track_blob_multi<Event, MultiBlobs, EventToBlob, HandleBlob>(
102 |             multi_blobs,
103 |             prob_threshold,
104 |             position_inertia,
105 |             variance_inertia,
106 |             std::forward<EventToBlob>(event_to_blob),
107 |             std::forward<HandleBlob>(handle_blob));
108 |     }
109 | }
110 | 


--------------------------------------------------------------------------------
/source/compute_flow.hpp:
--------------------------------------------------------------------------------
  1 | #pragma once
  2 | 
  3 | #include <cmath>
  4 | #include <cstdint>
  5 | #include <utility>
  6 | #include <vector>
  7 | 
  8 | /// tarsier is a collection of event handlers.
  9 | namespace tarsier {
 10 |     /// compute_flow evaluates the optical flow.
 11 |     template <typename Event, typename Flow, typename EventToFlow, typename HandleFlow>
 12 |     class compute_flow {
 13 |         public:
 14 |         compute_flow(
 15 |             uint16_t width,
 16 |             uint16_t height,
 17 |             uint16_t spatial_window,
 18 |             uint64_t temporal_window,
 19 |             std::size_t minimum_number_of_events,
 20 |             EventToFlow&& event_to_flow,
 21 |             HandleFlow&& handle_flow) :
 22 |             _width(width),
 23 |             _height(height),
 24 |             _spatial_window(spatial_window),
 25 |             _temporal_window(temporal_window),
 26 |             _minimum_number_of_events(minimum_number_of_events),
 27 |             _event_to_flow(std::forward<EventToFlow>(event_to_flow)),
 28 |             _handle_flow(std::forward<HandleFlow>(handle_flow)),
 29 |             _ts(width * height, 0) {}
 30 |         compute_flow(const compute_flow&) = delete;
 31 |         compute_flow(compute_flow&&) = default;
 32 |         compute_flow& operator=(const compute_flow&) = delete;
 33 |         compute_flow& operator=(compute_flow&&) = default;
 34 |         virtual ~compute_flow() = default;
 35 | 
 36 |         /// operator() handles an event.
 37 |         virtual void operator()(Event event) {
 38 |             _ts[event.x + event.y * _width] = event.t;
 39 |             const auto t_threshold = (event.t <= _temporal_window ? 0 : event.t - _temporal_window);
 40 |             std::vector<point> points;
 41 |             for (uint16_t y = (event.y <= _spatial_window ? 0 : event.y - _spatial_window);
 42 |                  y <= (event.y >= _height - 1 - _spatial_window ? _height - 1 : event.y + _spatial_window);
 43 |                  ++y) {
 44 |                 for (uint16_t x = (event.x <= _spatial_window ? 0 : event.x - _spatial_window);
 45 |                      x <= (event.x >= _width - 1 - _spatial_window ? _width - 1 : event.x + _spatial_window);
 46 |                      ++x) {
 47 |                     const auto t = _ts[x + y * _width];
 48 |                     if (t > t_threshold) {
 49 |                         points.push_back(point{
 50 |                             static_cast<float>(t),
 51 |                             static_cast<float>(x),
 52 |                             static_cast<float>(y),
 53 |                         });
 54 |                     }
 55 |                 }
 56 |             }
 57 |             if (points.size() >= _minimum_number_of_events) {
 58 |                 auto t_mean = 0.0f;
 59 |                 auto x_mean = 0.0f;
 60 |                 auto y_mean = 0.0f;
 61 |                 for (auto point : points) {
 62 |                     t_mean += point.t;
 63 |                     x_mean += point.x;
 64 |                     y_mean += point.y;
 65 |                 }
 66 |                 t_mean /= points.size();
 67 |                 x_mean /= points.size();
 68 |                 y_mean /= points.size();
 69 |                 auto tx_sum = 0.0f;
 70 |                 auto ty_sum = 0.0f;
 71 |                 auto xx_sum = 0.0f;
 72 |                 auto xy_sum = 0.0f;
 73 |                 auto yy_sum = 0.0f;
 74 |                 for (auto point : points) {
 75 |                     const auto t_delta = point.t - t_mean;
 76 |                     const auto x_delta = point.x - x_mean;
 77 |                     const auto y_delta = point.y - y_mean;
 78 |                     tx_sum += t_delta * x_delta;
 79 |                     ty_sum += t_delta * y_delta;
 80 |                     xx_sum += x_delta * x_delta;
 81 |                     xy_sum += x_delta * y_delta;
 82 |                     yy_sum += y_delta * y_delta;
 83 |                 }
 84 |                 const auto t_determinant = xx_sum * yy_sum - xy_sum * xy_sum;
 85 |                 const auto x_determinant = tx_sum * yy_sum - ty_sum * xy_sum;
 86 |                 const auto y_determinant = ty_sum * xx_sum - tx_sum * xy_sum;
 87 |                 const auto inverse_squares_sum = 1.0f / (x_determinant * x_determinant + y_determinant * y_determinant);
 88 |                 _handle_flow(_event_to_flow(
 89 |                     event,
 90 |                     t_determinant * x_determinant * inverse_squares_sum,
 91 |                     t_determinant * y_determinant * inverse_squares_sum));
 92 |             }
 93 |         }
 94 | 
 95 |         protected:
 96 |         /// point represents a point in xyt space.
 97 |         struct point {
 98 |             float t;
 99 |             float x;
100 |             float y;
101 |         };
102 | 
103 |         const uint16_t _width;
104 |         const uint16_t _height;
105 |         const uint16_t _spatial_window;
106 |         const uint64_t _temporal_window;
107 |         const std::size_t _minimum_number_of_events;
108 |         EventToFlow _event_to_flow;
109 |         HandleFlow _handle_flow;
110 |         std::vector<uint64_t> _ts;
111 |     };
112 | 
113 |     /// make_compute_flow creates an optical flow estimator from functors.
114 |     template <typename Event, typename Flow, typename EventToFlow, typename HandleFlow>
115 |     inline compute_flow<Event, Flow, EventToFlow, HandleFlow> make_compute_flow(
116 |         uint16_t width,
117 |         uint16_t height,
118 |         uint16_t spatial_window,
119 |         uint64_t temporal_window,
120 |         std::size_t minimum_number_of_events,
121 |         EventToFlow&& EventToflow,
122 |         HandleFlow&& handle_flow) {
123 |         return compute_flow<Event, Flow, EventToFlow, HandleFlow>(
124 |             width,
125 |             height,
126 |             spatial_window,
127 |             temporal_window,
128 |             minimum_number_of_events,
129 |             std::forward<EventToFlow>(EventToflow),
130 |             std::forward<HandleFlow>(handle_flow));
131 |     }
132 | }
133 | 


--------------------------------------------------------------------------------
/source/merge.hpp:
--------------------------------------------------------------------------------
  1 | #pragma once
  2 | 
  3 | #include <array>
  4 | #include <atomic>
  5 | #include <chrono>
  6 | #include <limits>
  7 | #include <memory>
  8 | #include <stdexcept>
  9 | #include <thread>
 10 | #include <vector>
 11 | 
 12 | /// tarsier is a collection of event handlers.
 13 | namespace tarsier {
 14 |     /// merge creates a unique event stream from sources running on different
 15 |     /// threads.
 16 |     template <std::size_t sources, typename Event, typename HandleEvent>
 17 |     class merge {
 18 |         public:
 19 |         merge(
 20 |             std::size_t fifo_size,
 21 |             std::chrono::high_resolution_clock::duration sleep_duration,
 22 |             HandleEvent&& handle_event) :
 23 |             _fifo_size(fifo_size),
 24 |             _sleep_duration(sleep_duration),
 25 |             _handle_event(std::forward<HandleEvent>(handle_event)),
 26 |             _running(true) {
 27 |             for (auto& fifo : _fifos) {
 28 |                 fifo.events.resize(_fifo_size);
 29 |                 fifo.head.store(0, std::memory_order_release);
 30 |                 fifo.tail.store(0, std::memory_order_release);
 31 |             }
 32 |             _loop = std::thread([this]() {
 33 |                 while (_running.load(std::memory_order_acquire)) {
 34 |                     auto minimum_t = std::numeric_limits<uint64_t>::max();
 35 |                     std::size_t minimum_source = 0;
 36 |                     auto dispatch = true;
 37 |                     for (std::size_t source = 0; source < sources; ++source) {
 38 |                         if (_next_events_and_exists[source].second) {
 39 |                             if (dispatch && _next_events_and_exists[source].first.t < minimum_t) {
 40 |                                 minimum_t = _next_events_and_exists[source].first.t;
 41 |                                 minimum_source = source;
 42 |                             }
 43 |                         } else {
 44 |                             const auto current_head = _fifos[source].head.load(std::memory_order_relaxed);
 45 |                             if (current_head == _fifos[source].tail.load(std::memory_order_acquire)) {
 46 |                                 dispatch = false;
 47 |                             } else {
 48 |                                 _next_events_and_exists[source].first = _fifos[source].events[current_head];
 49 |                                 _fifos[source].head.store((current_head + 1) % _fifo_size, std::memory_order_release);
 50 |                                 _next_events_and_exists[source].second = true;
 51 |                                 if (dispatch && _next_events_and_exists[source].first.t < minimum_t) {
 52 |                                     minimum_t = _next_events_and_exists[source].first.t;
 53 |                                     minimum_source = source;
 54 |                                 }
 55 |                             }
 56 |                         }
 57 |                     }
 58 |                     if (dispatch) {
 59 |                         _handle_event(_next_events_and_exists[minimum_source].first);
 60 |                         _next_events_and_exists[minimum_source].second = false;
 61 |                     } else {
 62 |                         std::this_thread::sleep_for(_sleep_duration);
 63 |                     }
 64 |                 }
 65 |             });
 66 |         }
 67 |         merge(const merge&) = delete;
 68 |         merge(merge&&) = default;
 69 |         merge& operator=(const merge&) = delete;
 70 |         merge& operator=(merge&&) = default;
 71 |         virtual ~merge() {
 72 |             _running.store(false, std::memory_order_release);
 73 |             _loop.join();
 74 |             std::array<bool, sources> has_events;
 75 |             has_events.fill(true);
 76 |             for (;;) {
 77 |                 auto minimum_t = std::numeric_limits<uint64_t>::max();
 78 |                 std::size_t minimum_source = 0;
 79 |                 for (std::size_t source = 0; source < sources; ++source) {
 80 |                     if (has_events[source]) {
 81 |                         if (_next_events_and_exists[source].second) {
 82 |                             minimum_t = _next_events_and_exists[source].first.t;
 83 |                             minimum_source = source;
 84 |                         } else {
 85 |                             const auto current_head = _fifos[source].head.load(std::memory_order_relaxed);
 86 |                             if (current_head == _fifos[source].tail.load(std::memory_order_acquire)) {
 87 |                                 has_events[source] = false;
 88 |                             } else {
 89 |                                 _next_events_and_exists[source].first = _fifos[source].events[current_head];
 90 |                                 _fifos[source].head.store((current_head + 1) % _fifo_size, std::memory_order_release);
 91 |                                 _next_events_and_exists[source].second = true;
 92 |                                 if (_next_events_and_exists[source].first.t < minimum_t) {
 93 |                                     minimum_t = _next_events_and_exists[source].first.t;
 94 |                                     minimum_source = source;
 95 |                                 }
 96 |                             }
 97 |                         }
 98 |                     }
 99 |                 }
100 |                 if (minimum_t == std::numeric_limits<uint64_t>::max()) {
101 |                     break;
102 |                 } else {
103 |                     _handle_event(_next_events_and_exists[minimum_source].first);
104 |                     _next_events_and_exists[minimum_source].second = false;
105 |                 }
106 |             }
107 |         }
108 | 
109 |         /// push handles an event from a specified source.
110 |         template <std::size_t source>
111 |         bool push(Event event) {
112 |             static_assert(source < sources, "source must be in the integer range [0, sources[");
113 |             return push(source, event);
114 |         }
115 |         bool push(std::size_t source, Event event) {
116 |             const auto current_tail = _fifos[source].tail.load(std::memory_order_relaxed);
117 |             const auto next_tail = (current_tail + 1) % _fifo_size;
118 |             if (next_tail == _fifos[source].head.load(std::memory_order_acquire)) {
119 |                 return false;
120 |             }
121 |             _fifos[source].events[current_tail] = event;
122 |             _fifos[source].tail.store(next_tail, std::memory_order_release);
123 |             return true;
124 |         }
125 | 
126 |         protected:
127 |         /// fifo stores the variables of a thread-safe fifo.
128 |         struct fifo {
129 |             std::vector<Event> events;
130 |             std::atomic<std::size_t> head;
131 |             std::atomic<std::size_t> tail;
132 |         };
133 | 
134 |         const std::size_t _fifo_size;
135 |         const std::chrono::high_resolution_clock::duration _sleep_duration;
136 |         HandleEvent _handle_event;
137 |         std::array<fifo, sources> _fifos;
138 |         std::array<std::pair<Event, bool>, sources> _next_events_and_exists;
139 |         std::thread _loop;
140 |         std::atomic_bool _running;
141 |     };
142 | 
143 |     /// make_merge creates a merge from a functor.
144 |     template <std::size_t sources, typename Event, typename HandleEvent>
145 |     inline std::unique_ptr<merge<sources, Event, HandleEvent>> make_merge(
146 |         std::size_t fifo_size,
147 |         std::chrono::high_resolution_clock::duration sleep_duration,
148 |         HandleEvent&& handle_event) {
149 |         return std::unique_ptr<merge<sources, Event, HandleEvent>>(
150 |             new merge<sources, Event, HandleEvent>(fifo_size, sleep_duration, std::forward<HandleEvent>(handle_event)));
151 |     }
152 | }
153 | 


--------------------------------------------------------------------------------
/template.lua:
--------------------------------------------------------------------------------
  1 | local json = (loadfile 'third_party/json.lua/json.lua')()
  2 | 
  3 | -- check throws an error if the given variable does not exist or does not have the expected type.
  4 | local function check(name, value, expected_type, json_type_name)
  5 |     if value == nil then
  6 |         error(name .. ' is not defined')
  7 |     end
  8 |     if type(value) ~= expected_type then
  9 |         error(name .. ' has an incorrect type (expected ' .. json_type_name .. ')')
 10 |     end
 11 | end
 12 | 
 13 | return function(configuration_filename)
 14 |     local configuration_file = io.open(configuration_filename, 'r')
 15 |     if configuration_file == nil then
 16 |         error('\'' .. configuration_filename .. '\' could not be open for reading')
 17 |     end
 18 |     configuration = json.decode(configuration_file:read('*a'))
 19 |     configuration_file:close()
 20 |     if type(configuration) ~= 'table' then
 21 |         error('\'' .. configuration_filename .. '\' does not contain an object')
 22 |     end
 23 |     check(
 24 |         '\'' .. 'configuration_filename' .. '\'',
 25 |         configuration,
 26 |         'table',
 27 |         'an object')
 28 |     check(
 29 |         '\'' .. configuration_filename .. '\'[\'filename\']',
 30 |         configuration['filename'],
 31 |         'string',
 32 |         'a string')
 33 |     check(
 34 |         '\'' .. configuration_filename .. '\'[\'name\']',
 35 |         configuration['name'],
 36 |         'string',
 37 |         'a string')
 38 |     check(
 39 |         '\'' .. configuration_filename .. '\'[\'description\']',
 40 |         configuration['description'],
 41 |         'table',
 42 |         'an array')
 43 |     check(
 44 |         '\'' .. configuration_filename .. '\'[\'template_parameters\']',
 45 |         configuration['template_parameters'],
 46 |         'table',
 47 |         'an array')
 48 |     check(
 49 |         '\'' .. configuration_filename .. '\'[\'parameters\']',
 50 |         configuration['parameters'],
 51 |         'table',
 52 |         'an array')
 53 |     check(
 54 |         '\'' .. configuration_filename .. '\'[\'input\']',
 55 |         configuration['input'],
 56 |         'table',
 57 |         'an object')
 58 |     for key, value in pairs(configuration['description']) do
 59 |         if type(key) ~= 'number' then
 60 |             error('\'' .. configuration_filename .. '\'[\'description\'] is not an array')
 61 |         end
 62 |         check(
 63 |             '\'' .. configuration_filename .. '\'[\'description\'][' .. tostring(key - 1) .. ']',
 64 |             value,
 65 |             'string',
 66 |             'a string')
 67 |     end
 68 |     for key, value in pairs(configuration['template_parameters']) do
 69 |         if type(key) ~= 'number' then
 70 |             error('\'' .. configuration_filename .. '\'[\'template_parameters\'] is not an array')
 71 |         end
 72 |         local name = '\'' .. configuration_filename .. '\'[\'template_parameters\'][' .. tostring(key - 1) .. ']'
 73 |         check(
 74 |             name,
 75 |             value,
 76 |             'table',
 77 |             'an object')
 78 |         check(
 79 |             name .. '[\'name\']',
 80 |             value['name'],
 81 |             'string',
 82 |             'a string')
 83 |         check(
 84 |             name .. '[\'type\']',
 85 |             value['type'],
 86 |             'string',
 87 |             'a string',
 88 |             true)
 89 |     end
 90 |     for key, value in pairs(configuration['parameters']) do
 91 |         if type(key) ~= 'number' then
 92 |             error('\'' .. configuration_filename .. '\'[\'parameters\'] is not an array')
 93 |         end
 94 |         local name = '\'' .. configuration_filename .. '\'[\'parameters\'][' .. tostring(key - 1) .. ']'
 95 |         check(
 96 |             name,
 97 |             value,
 98 |             'table',
 99 |             'an object')
100 |         check(
101 |             name .. '[\'name\']',
102 |             value['name'],
103 |             'string',
104 |             'a string')
105 |         check(
106 |             name .. '[\'type\']',
107 |             value['type'],
108 |             'string',
109 |             'a string')
110 |         check(
111 |             name .. '[\'store\']',
112 |             value['store'],
113 |             'string',
114 |             'a string')
115 |         if value['store'] ~= nil
116 |             and value['store'] ~= 'no'
117 |             and value['store'] ~= 'mutable'
118 |             and value['store'] ~= 'constant'
119 |             and value['store'] ~= 'forward' then
120 |             error(name .. '[\'store\'] must be one of {\'no\', \'mutable\', \'constant\', \'forward\'}')
121 |         end
122 |     end
123 |     check(
124 |         '\'' .. configuration_filename .. '\'[\'input\'][\'name\']',
125 |         configuration['input']['name'],
126 |         'string',
127 |         'a string')
128 |     check(
129 |         '\'' .. configuration_filename .. '\'[\'input\'][\'type\']',
130 |         configuration['input']['type'],
131 |         'string',
132 |         'a string')
133 |     local output_file = io.open(configuration['filename'], 'w')
134 |     if output_file == nil then
135 |         error('\'' .. configuration['filename'] .. '\' could not be open for writing')
136 |     end
137 |     local template_parameters = {}
138 |     local template_parameters_names = {}
139 |     for index, parameter in ipairs(configuration['template_parameters']) do
140 |         template_parameters[index] = parameter['type'] .. ' ' .. parameter['name']
141 |         template_parameters_names[index] = parameter['name']
142 |     end
143 |     local parameters = {}
144 |     local parameters_names = {}
145 |     for index, parameter in ipairs(configuration['parameters']) do
146 |         if parameter['store'] == 'forward' then
147 |             parameters[index] = parameter['type'] .. '&& ' .. parameter['name']
148 |             parameters_names[index] = 'std::forward<' .. parameter['type'] .. '>(' .. parameter['name'] .. ')'
149 |         else
150 |             parameters[index] = parameter['type'] .. ' ' .. parameter['name']
151 |             parameters_names[index] = parameter['name']
152 |         end
153 |     end
154 |     local initialization_parameters = {}
155 |     local initialization_parameters_index = 1
156 |     local has_initialization_parameters = false
157 |     for index, parameter in ipairs(configuration['parameters']) do
158 |         if parameter['store'] ~= 'no' then
159 |             has_initialization_parameters = true
160 |             if parameter['store'] == 'forward' then
161 |                 initialization_parameters[initialization_parameters_index] = '_' ..
162 |                     parameter['name'] ..
163 |                     '(std::forward<' ..
164 |                     parameter['type'] ..
165 |                     '>(' ..
166 |                     parameter['name'] ..
167 |                     '))'
168 |             else
169 |                 initialization_parameters[initialization_parameters_index] = '_' .. parameter['name'] .. '(' .. parameter['name'] .. ')'
170 |             end
171 |             initialization_parameters_index = initialization_parameters_index + 1
172 |         end
173 |     end
174 |     output_file:write(
175 |         '#pragma once\n\n',
176 |         '#include <utility>\n\n',
177 |         '/// tarsier is a collection of event handlers.\n',
178 |         'namespace tarsier {\n')
179 |     for key, value in pairs(configuration['description']) do
180 |         output_file:write('    /// ', value, '\n')
181 |     end
182 |     output_file:write(
183 |         '    template <', table.concat(template_parameters, ', '), '>\n',
184 |         '    class ', configuration['name'], ' {\n',
185 |         '        public:\n',
186 |         '        ', configuration['name'], '(', table.concat(parameters, ', '), ')')
187 |     if has_initialization_parameters then
188 |         output_file:write(' :\n',
189 |             '            ', table.concat(initialization_parameters, ', '))
190 |     end
191 |     output_file:write(' {\n',
192 |         '        }\n',
193 |         '        ', configuration['name'], '(const ', configuration['name'], '&) = delete;\n',
194 |         '        ', configuration['name'], '(', configuration['name'], '&&) = default;\n',
195 |         '        ', configuration['name'], '& operator=(const ', configuration['name'], '&) = delete;\n',
196 |         '        ', configuration['name'], '& operator=(', configuration['name'], '&&) = default;\n',
197 |         '        virtual ~', configuration['name'], '() {}\n\n',
198 |         '        /// operator() handles an event.\n',
199 |         '        virtual void operator()(', configuration['input']['type'], ' ', configuration['input']['name'], ') {\n',
200 |         '        }\n\n',
201 |         '        protected:\n')
202 |     for index, parameter in ipairs(configuration['parameters']) do
203 |         output_file:write('        ')
204 |         if parameter['store'] ~= 'no' then
205 |             if parameter['store'] == 'constant' then
206 |                 output_file:write('const ')
207 |             end
208 |             output_file:write(parameter['type'], ' _', parameter['name'], ';\n')
209 |         end
210 |     end
211 |     output_file:write('    };\n\n',
212 |         '    /// make_', configuration['name'], ' creates a')
213 |     if string.find(configuration['name'], '^\s*[AEIOUaeiou]') then
214 |         output_file:write('n')
215 |     end
216 |     output_file:write(' ', configuration['name'], ' from functors.\n',
217 |         '    template <', table.concat(template_parameters, ', '), '>\n',
218 |         '    inline ', configuration['name'], '<', table.concat(template_parameters_names, ', '), '> make_', configuration['name'], '(\n',
219 |         '        ',  table.concat(parameters, ', '), ') {\n',
220 |         '        return ', configuration['name'], '<', table.concat(template_parameters_names, ', '), '>(\n',
221 |         '            ', table.concat(parameters_names, ', '), ');\n',
222 |         '    }\n',
223 |         '}\n')
224 |     output_file:close()
225 | end
226 | 


--------------------------------------------------------------------------------
/LICENSE.txt:
--------------------------------------------------------------------------------
  1 | GNU GENERAL PUBLIC LICENSE
  2 |                        Version 3, 29 June 2007
  3 | 
  4 |  Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
  5 |  Everyone is permitted to copy and distribute verbatim copies
  6 |  of this license document, but changing it is not allowed.
  7 | 
  8 |                             Preamble
  9 | 
 10 |   The GNU General Public License is a free, copyleft license for
 11 | software and other kinds of works.
 12 | 
 13 |   The licenses for most software and other practical works are designed
 14 | to take away your freedom to share and change the works.  By contrast,
 15 | the GNU General Public License is intended to guarantee your freedom to
 16 | share and change all versions of a program--to make sure it remains free
 17 | software for all its users.  We, the Free Software Foundation, use the
 18 | GNU General Public License for most of our software; it applies also to
 19 | any other work released this way by its authors.  You can apply it to
 20 | your programs, too.
 21 | 
 22 |   When we speak of free software, we are referring to freedom, not
 23 | price.  Our General Public Licenses are designed to make sure that you
 24 | have the freedom to distribute copies of free software (and charge for
 25 | them if you wish), that you receive source code or can get it if you
 26 | want it, that you can change the software or use pieces of it in new
 27 | free programs, and that you know you can do these things.
 28 | 
 29 |   To protect your rights, we need to prevent others from denying you
 30 | these rights or asking you to surrender the rights.  Therefore, you have
 31 | certain responsibilities if you distribute copies of the software, or if
 32 | you modify it: responsibilities to respect the freedom of others.
 33 | 
 34 |   For example, if you distribute copies of such a program, whether
 35 | gratis or for a fee, you must pass on to the recipients the same
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 38 | know their rights.
 39 | 
 40 |   Developers that use the GNU GPL protect your rights with two steps:
 41 | (1) assert copyright on the software, and (2) offer you this License
 42 | giving you legal permission to copy, distribute and/or modify it.
 43 | 
 44 |   For the developers' and authors' protection, the GPL clearly explains
 45 | that there is no warranty for this free software.  For both users' and
 46 | authors' sake, the GPL requires that modified versions be marked as
 47 | changed, so that their problems will not be attributed erroneously to
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 68 |   The precise terms and conditions for copying, distribution and
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 70 | 
 71 |                        TERMS AND CONDITIONS
 72 | 
 73 |   0. Definitions.
 74 | 
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 76 | 
 77 |   "Copyright" also means copyright-like laws that apply to other kinds of
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153 | 
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171 | for you must do so exclusively on your behalf, under your direction
172 | and control, on terms that prohibit them from making any copies of
173 | your copyrighted material outside their relationship with you.
174 | 
175 |   Conveying under any other circumstances is permitted solely under
176 | the conditions stated below.  Sublicensing is not allowed; section 10
177 | makes it unnecessary.
178 | 
179 |   3. Protecting Users' Legal Rights From Anti-Circumvention Law.
180 | 
181 |   No covered work shall be deemed part of an effective technological
182 | measure under any applicable law fulfilling obligations under article
183 | 11 of the WIPO copyright treaty adopted on 20 December 1996, or
184 | similar laws prohibiting or restricting circumvention of such
185 | measures.
186 | 
187 |   When you convey a covered work, you waive any legal power to forbid
188 | circumvention of technological measures to the extent such circumvention
189 | is effected by exercising rights under this License with respect to
190 | the covered work, and you disclaim any intention to limit operation or
191 | modification of the work as a means of enforcing, against the work's
192 | users, your or third parties' legal rights to forbid circumvention of
193 | technological measures.
194 | 
195 |   4. Conveying Verbatim Copies.
196 | 
197 |   You may convey verbatim copies of the Program's source code as you
198 | receive it, in any medium, provided that you conspicuously and
199 | appropriately publish on each copy an appropriate copyright notice;
200 | keep intact all notices stating that this License and any
201 | non-permissive terms added in accord with section 7 apply to the code;
202 | keep intact all notices of the absence of any warranty; and give all
203 | recipients a copy of this License along with the Program.
204 | 
205 |   You may charge any price or no price for each copy that you convey,
206 | and you may offer support or warranty protection for a fee.
207 | 
208 |   5. Conveying Modified Source Versions.
209 | 
210 |   You may convey a work based on the Program, or the modifications to
211 | produce it from the Program, in the form of source code under the
212 | terms of section 4, provided that you also meet all of these conditions:
213 | 
214 |     a) The work must carry prominent notices stating that you modified
215 |     it, and giving a relevant date.
216 | 
217 |     b) The work must carry prominent notices stating that it is
218 |     released under this License and any conditions added under section
219 |     7.  This requirement modifies the requirement in section 4 to
220 |     "keep intact all notices".
221 | 
222 |     c) You must license the entire work, as a whole, under this
223 |     License to anyone who comes into possession of a copy.  This
224 |     License will therefore apply, along with any applicable section 7
225 |     additional terms, to the whole of the work, and all its parts,
226 |     regardless of how they are packaged.  This License gives no
227 |     permission to license the work in any other way, but it does not
228 |     invalidate such permission if you have separately received it.
229 | 
230 |     d) If the work has interactive user interfaces, each must display
231 |     Appropriate Legal Notices; however, if the Program has interactive
232 |     interfaces that do not display Appropriate Legal Notices, your
233 |     work need not make them do so.
234 | 
235 |   A compilation of a covered work with other separate and independent
236 | works, which are not by their nature extensions of the covered work,
237 | and which are not combined with it such as to form a larger program,
238 | in or on a volume of a storage or distribution medium, is called an
239 | "aggregate" if the compilation and its resulting copyright are not
240 | used to limit the access or legal rights of the compilation's users
241 | beyond what the individual works permit.  Inclusion of a covered work
242 | in an aggregate does not cause this License to apply to the other
243 | parts of the aggregate.
244 | 
245 |   6. Conveying Non-Source Forms.
246 | 
247 |   You may convey a covered work in object code form under the terms
248 | of sections 4 and 5, provided that you also convey the
249 | machine-readable Corresponding Source under the terms of this License,
250 | in one of these ways:
251 | 
252 |     a) Convey the object code in, or embodied in, a physical product
253 |     (including a physical distribution medium), accompanied by the
254 |     Corresponding Source fixed on a durable physical medium
255 |     customarily used for software interchange.
256 | 
257 |     b) Convey the object code in, or embodied in, a physical product
258 |     (including a physical distribution medium), accompanied by a
259 |     written offer, valid for at least three years and valid for as
260 |     long as you offer spare parts or customer support for that product
261 |     model, to give anyone who possesses the object code either (1) a
262 |     copy of the Corresponding Source for all the software in the
263 |     product that is covered by this License, on a durable physical
264 |     medium customarily used for software interchange, for a price no
265 |     more than your reasonable cost of physically performing this
266 |     conveying of source, or (2) access to copy the
267 |     Corresponding Source from a network server at no charge.
268 | 
269 |     c) Convey individual copies of the object code with a copy of the
270 |     written offer to provide the Corresponding Source.  This
271 |     alternative is allowed only occasionally and noncommercially, and
272 |     only if you received the object code with such an offer, in accord
273 |     with subsection 6b.
274 | 
275 |     d) Convey the object code by offering access from a designated
276 |     place (gratis or for a charge), and offer equivalent access to the
277 |     Corresponding Source in the same way through the same place at no
278 |     further charge.  You need not require recipients to copy the
279 |     Corresponding Source along with the object code.  If the place to
280 |     copy the object code is a network server, the Corresponding Source
281 |     may be on a different server (operated by you or a third party)
282 |     that supports equivalent copying facilities, provided you maintain
283 |     clear directions next to the object code saying where to find the
284 |     Corresponding Source.  Regardless of what server hosts the
285 |     Corresponding Source, you remain obligated to ensure that it is
286 |     available for as long as needed to satisfy these requirements.
287 | 
288 |     e) Convey the object code using peer-to-peer transmission, provided
289 |     you inform other peers where the object code and Corresponding
290 |     Source of the work are being offered to the general public at no
291 |     charge under subsection 6d.
292 | 
293 |   A separable portion of the object code, whose source code is excluded
294 | from the Corresponding Source as a System Library, need not be
295 | included in conveying the object code work.
296 | 
297 |   A "User Product" is either (1) a "consumer product", which means any
298 | tangible personal property which is normally used for personal, family,
299 | or household purposes, or (2) anything designed or sold for incorporation
300 | into a dwelling.  In determining whether a product is a consumer product,
301 | doubtful cases shall be resolved in favor of coverage.  For a particular
302 | product received by a particular user, "normally used" refers to a
303 | typical or common use of that class of product, regardless of the status
304 | of the particular user or of the way in which the particular user
305 | actually uses, or expects or is expected to use, the product.  A product
306 | is a consumer product regardless of whether the product has substantial
307 | commercial, industrial or non-consumer uses, unless such uses represent
308 | the only significant mode of use of the product.
309 | 
310 |   "Installation Information" for a User Product means any methods,
311 | procedures, authorization keys, or other information required to install
312 | and execute modified versions of a covered work in that User Product from
313 | a modified version of its Corresponding Source.  The information must
314 | suffice to ensure that the continued functioning of the modified object
315 | code is in no case prevented or interfered with solely because
316 | modification has been made.
317 | 
318 |   If you convey an object code work under this section in, or with, or
319 | specifically for use in, a User Product, and the conveying occurs as
320 | part of a transaction in which the right of possession and use of the
321 | User Product is transferred to the recipient in perpetuity or for a
322 | fixed term (regardless of how the transaction is characterized), the
323 | Corresponding Source conveyed under this section must be accompanied
324 | by the Installation Information.  But this requirement does not apply
325 | if neither you nor any third party retains the ability to install
326 | modified object code on the User Product (for example, the work has
327 | been installed in ROM).
328 | 
329 |   The requirement to provide Installation Information does not include a
330 | requirement to continue to provide support service, warranty, or updates
331 | for a work that has been modified or installed by the recipient, or for
332 | the User Product in which it has been modified or installed.  Access to a
333 | network may be denied when the modification itself materially and
334 | adversely affects the operation of the network or violates the rules and
335 | protocols for communication across the network.
336 | 
337 |   Corresponding Source conveyed, and Installation Information provided,
338 | in accord with this section must be in a format that is publicly
339 | documented (and with an implementation available to the public in
340 | source code form), and must require no special password or key for
341 | unpacking, reading or copying.
342 | 
343 |   7. Additional Terms.
344 | 
345 |   "Additional permissions" are terms that supplement the terms of this
346 | License by making exceptions from one or more of its conditions.
347 | Additional permissions that are applicable to the entire Program shall
348 | be treated as though they were included in this License, to the extent
349 | that they are valid under applicable law.  If additional permissions
350 | apply only to part of the Program, that part may be used separately
351 | under those permissions, but the entire Program remains governed by
352 | this License without regard to the additional permissions.
353 | 
354 |   When you convey a copy of a covered work, you may at your option
355 | remove any additional permissions from that copy, or from any part of
356 | it.  (Additional permissions may be written to require their own
357 | removal in certain cases when you modify the work.)  You may place
358 | additional permissions on material, added by you to a covered work,
359 | for which you have or can give appropriate copyright permission.
360 | 
361 |   Notwithstanding any other provision of this License, for material you
362 | add to a covered work, you may (if authorized by the copyright holders of
363 | that material) supplement the terms of this License with terms:
364 | 
365 |     a) Disclaiming warranty or limiting liability differently from the
366 |     terms of sections 15 and 16 of this License; or
367 | 
368 |     b) Requiring preservation of specified reasonable legal notices or
369 |     author attributions in that material or in the Appropriate Legal
370 |     Notices displayed by works containing it; or
371 | 
372 |     c) Prohibiting misrepresentation of the origin of that material, or
373 |     requiring that modified versions of such material be marked in
374 |     reasonable ways as different from the original version; or
375 | 
376 |     d) Limiting the use for publicity purposes of names of licensors or
377 |     authors of the material; or
378 | 
379 |     e) Declining to grant rights under trademark law for use of some
380 |     trade names, trademarks, or service marks; or
381 | 
382 |     f) Requiring indemnification of licensors and authors of that
383 |     material by anyone who conveys the material (or modified versions of
384 |     it) with contractual assumptions of liability to the recipient, for
385 |     any liability that these contractual assumptions directly impose on
386 |     those licensors and authors.
387 | 
388 |   All other non-permissive additional terms are considered "further
389 | restrictions" within the meaning of section 10.  If the Program as you
390 | received it, or any part of it, contains a notice stating that it is
391 | governed by this License along with a term that is a further
392 | restriction, you may remove that term.  If a license document contains
393 | a further restriction but permits relicensing or conveying under this
394 | License, you may add to a covered work material governed by the terms
395 | of that license document, provided that the further restriction does
396 | not survive such relicensing or conveying.
397 | 
398 |   If you add terms to a covered work in accord with this section, you
399 | must place, in the relevant source files, a statement of the
400 | additional terms that apply to those files, or a notice indicating
401 | where to find the applicable terms.
402 | 
403 |   Additional terms, permissive or non-permissive, may be stated in the
404 | form of a separately written license, or stated as exceptions;
405 | the above requirements apply either way.
406 | 
407 |   8. Termination.
408 | 
409 |   You may not propagate or modify a covered work except as expressly
410 | provided under this License.  Any attempt otherwise to propagate or
411 | modify it is void, and will automatically terminate your rights under
412 | this License (including any patent licenses granted under the third
413 | paragraph of section 11).
414 | 
415 |   However, if you cease all violation of this License, then your
416 | license from a particular copyright holder is reinstated (a)
417 | provisionally, unless and until the copyright holder explicitly and
418 | finally terminates your license, and (b) permanently, if the copyright
419 | holder fails to notify you of the violation by some reasonable means
420 | prior to 60 days after the cessation.
421 | 
422 |   Moreover, your license from a particular copyright holder is
423 | reinstated permanently if the copyright holder notifies you of the
424 | violation by some reasonable means, this is the first time you have
425 | received notice of violation of this License (for any work) from that
426 | copyright holder, and you cure the violation prior to 30 days after
427 | your receipt of the notice.
428 | 
429 |   Termination of your rights under this section does not terminate the
430 | licenses of parties who have received copies or rights from you under
431 | this License.  If your rights have been terminated and not permanently
432 | reinstated, you do not qualify to receive new licenses for the same
433 | material under section 10.
434 | 
435 |   9. Acceptance Not Required for Having Copies.
436 | 
437 |   You are not required to accept this License in order to receive or
438 | run a copy of the Program.  Ancillary propagation of a covered work
439 | occurring solely as a consequence of using peer-to-peer transmission
440 | to receive a copy likewise does not require acceptance.  However,
441 | nothing other than this License grants you permission to propagate or
442 | modify any covered work.  These actions infringe copyright if you do
443 | not accept this License.  Therefore, by modifying or propagating a
444 | covered work, you indicate your acceptance of this License to do so.
445 | 
446 |   10. Automatic Licensing of Downstream Recipients.
447 | 
448 |   Each time you convey a covered work, the recipient automatically
449 | receives a license from the original licensors, to run, modify and
450 | propagate that work, subject to this License.  You are not responsible
451 | for enforcing compliance by third parties with this License.
452 | 
453 |   An "entity transaction" is a transaction transferring control of an
454 | organization, or substantially all assets of one, or subdividing an
455 | organization, or merging organizations.  If propagation of a covered
456 | work results from an entity transaction, each party to that
457 | transaction who receives a copy of the work also receives whatever
458 | licenses to the work the party's predecessor in interest had or could
459 | give under the previous paragraph, plus a right to possession of the
460 | Corresponding Source of the work from the predecessor in interest, if
461 | the predecessor has it or can get it with reasonable efforts.
462 | 
463 |   You may not impose any further restrictions on the exercise of the
464 | rights granted or affirmed under this License.  For example, you may
465 | not impose a license fee, royalty, or other charge for exercise of
466 | rights granted under this License, and you may not initiate litigation
467 | (including a cross-claim or counterclaim in a lawsuit) alleging that
468 | any patent claim is infringed by making, using, selling, offering for
469 | sale, or importing the Program or any portion of it.
470 | 
471 |   11. Patents.
472 | 
473 |   A "contributor" is a copyright holder who authorizes use under this
474 | License of the Program or a work on which the Program is based.  The
475 | work thus licensed is called the contributor's "contributor version".
476 | 
477 |   A contributor's "essential patent claims" are all patent claims
478 | owned or controlled by the contributor, whether already acquired or
479 | hereafter acquired, that would be infringed by some manner, permitted
480 | by this License, of making, using, or selling its contributor version,
481 | but do not include claims that would be infringed only as a
482 | consequence of further modification of the contributor version.  For
483 | purposes of this definition, "control" includes the right to grant
484 | patent sublicenses in a manner consistent with the requirements of
485 | this License.
486 | 
487 |   Each contributor grants you a non-exclusive, worldwide, royalty-free
488 | patent license under the contributor's essential patent claims, to
489 | make, use, sell, offer for sale, import and otherwise run, modify and
490 | propagate the contents of its contributor version.
491 | 
492 |   In the following three paragraphs, a "patent license" is any express
493 | agreement or commitment, however denominated, not to enforce a patent
494 | (such as an express permission to practice a patent or covenant not to
495 | sue for patent infringement).  To "grant" such a patent license to a
496 | party means to make such an agreement or commitment not to enforce a
497 | patent against the party.
498 | 
499 |   If you convey a covered work, knowingly relying on a patent license,
500 | and the Corresponding Source of the work is not available for anyone
501 | to copy, free of charge and under the terms of this License, through a
502 | publicly available network server or other readily accessible means,
503 | then you must either (1) cause the Corresponding Source to be so
504 | available, or (2) arrange to deprive yourself of the benefit of the
505 | patent license for this particular work, or (3) arrange, in a manner
506 | consistent with the requirements of this License, to extend the patent
507 | license to downstream recipients.  "Knowingly relying" means you have
508 | actual knowledge that, but for the patent license, your conveying the
509 | covered work in a country, or your recipient's use of the covered work
510 | in a country, would infringe one or more identifiable patents in that
511 | country that you have reason to believe are valid.
512 | 
513 |   If, pursuant to or in connection with a single transaction or
514 | arrangement, you convey, or propagate by procuring conveyance of, a
515 | covered work, and grant a patent license to some of the parties
516 | receiving the covered work authorizing them to use, propagate, modify
517 | or convey a specific copy of the covered work, then the patent license
518 | you grant is automatically extended to all recipients of the covered
519 | work and works based on it.
520 | 
521 |   A patent license is "discriminatory" if it does not include within
522 | the scope of its coverage, prohibits the exercise of, or is
523 | conditioned on the non-exercise of one or more of the rights that are
524 | specifically granted under this License.  You may not convey a covered
525 | work if you are a party to an arrangement with a third party that is
526 | in the business of distributing software, under which you make payment
527 | to the third party based on the extent of your activity of conveying
528 | the work, and under which the third party grants, to any of the
529 | parties who would receive the covered work from you, a discriminatory
530 | patent license (a) in connection with copies of the covered work
531 | conveyed by you (or copies made from those copies), or (b) primarily
532 | for and in connection with specific products or compilations that
533 | contain the covered work, unless you entered into that arrangement,
534 | or that patent license was granted, prior to 28 March 2007.
535 | 
536 |   Nothing in this License shall be construed as excluding or limiting
537 | any implied license or other defenses to infringement that may
538 | otherwise be available to you under applicable patent law.
539 | 
540 |   12. No Surrender of Others' Freedom.
541 | 
542 |   If conditions are imposed on you (whether by court order, agreement or
543 | otherwise) that contradict the conditions of this License, they do not
544 | excuse you from the conditions of this License.  If you cannot convey a
545 | covered work so as to satisfy simultaneously your obligations under this
546 | License and any other pertinent obligations, then as a consequence you may
547 | not convey it at all.  For example, if you agree to terms that obligate you
548 | to collect a royalty for further conveying from those to whom you convey
549 | the Program, the only way you could satisfy both those terms and this
550 | License would be to refrain entirely from conveying the Program.
551 | 
552 |   13. Use with the GNU Affero General Public License.
553 | 
554 |   Notwithstanding any other provision of this License, you have
555 | permission to link or combine any covered work with a work licensed
556 | under version 3 of the GNU Affero General Public License into a single
557 | combined work, and to convey the resulting work.  The terms of this
558 | License will continue to apply to the part which is the covered work,
559 | but the special requirements of the GNU Affero General Public License,
560 | section 13, concerning interaction through a network will apply to the
561 | combination as such.
562 | 
563 |   14. Revised Versions of this License.
564 | 
565 |   The Free Software Foundation may publish revised and/or new versions of
566 | the GNU General Public License from time to time.  Such new versions will
567 | be similar in spirit to the present version, but may differ in detail to
568 | address new problems or concerns.
569 | 
570 |   Each version is given a distinguishing version number.  If the
571 | Program specifies that a certain numbered version of the GNU General
572 | Public License "or any later version" applies to it, you have the
573 | option of following the terms and conditions either of that numbered
574 | version or of any later version published by the Free Software
575 | Foundation.  If the Program does not specify a version number of the
576 | GNU General Public License, you may choose any version ever published
577 | by the Free Software Foundation.
578 | 
579 |   If the Program specifies that a proxy can decide which future
580 | versions of the GNU General Public License can be used, that proxy's
581 | public statement of acceptance of a version permanently authorizes you
582 | to choose that version for the Program.
583 | 
584 |   Later license versions may give you additional or different
585 | permissions.  However, no additional obligations are imposed on any
586 | author or copyright holder as a result of your choosing to follow a
587 | later version.
588 | 
589 |   15. Disclaimer of Warranty.
590 | 
591 |   THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
592 | APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
593 | HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
594 | OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
595 | THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
596 | PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
597 | IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
598 | ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
599 | 
600 |   16. Limitation of Liability.
601 | 
602 |   IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
603 | WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
604 | THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
605 | GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
606 | USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
607 | DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
608 | PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
609 | EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
610 | SUCH DAMAGES.
611 | 
612 |   17. Interpretation of Sections 15 and 16.
613 | 
614 |   If the disclaimer of warranty and limitation of liability provided
615 | above cannot be given local legal effect according to their terms,
616 | reviewing courts shall apply local law that most closely approximates
617 | an absolute waiver of all civil liability in connection with the
618 | Program, unless a warranty or assumption of liability accompanies a
619 | copy of the Program in return for a fee.
620 | 
621 |                      END OF TERMS AND CONDITIONS
622 | 
623 |             How to Apply These Terms to Your New Programs
624 | 
625 |   If you develop a new program, and you want it to be of the greatest
626 | possible use to the public, the best way to achieve this is to make it
627 | free software which everyone can redistribute and change under these terms.
628 | 
629 |   To do so, attach the following notices to the program.  It is safest
630 | to attach them to the start of each source file to most effectively
631 | state the exclusion of warranty; and each file should have at least
632 | the "copyright" line and a pointer to where the full notice is found.
633 | 
634 |     {one line to give the program's name and a brief idea of what it does.}
635 |     Copyright (C) {year}  {name of author}
636 | 
637 |     This program is free software: you can redistribute it and/or modify
638 |     it under the terms of the GNU General Public License as published by
639 |     the Free Software Foundation, either version 3 of the License, or
640 |     (at your option) any later version.
641 | 
642 |     This program is distributed in the hope that it will be useful,
643 |     but WITHOUT ANY WARRANTY; without even the implied warranty of
644 |     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
645 |     GNU General Public License for more details.
646 | 
647 |     You should have received a copy of the GNU General Public License
648 |     along with this program.  If not, see <http://www.gnu.org/licenses/>.
649 | 
650 | Also add information on how to contact you by electronic and paper mail.
651 | 
652 |   If the program does terminal interaction, make it output a short
653 | notice like this when it starts in an interactive mode:
654 | 
655 |     {project}  Copyright (C) {year}  {fullname}
656 |     This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
657 |     This is free software, and you are welcome to redistribute it
658 |     under certain conditions; type `show c' for details.
659 | 
660 | The hypothetical commands `show w' and `show c' should show the appropriate
661 | parts of the General Public License.  Of course, your program's commands
662 | might be different; for a GUI interface, you would use an "about box".
663 | 
664 |   You should also get your employer (if you work as a programmer) or school,
665 | if any, to sign a "copyright disclaimer" for the program, if necessary.
666 | For more information on this, and how to apply and follow the GNU GPL, see
667 | <http://www.gnu.org/licenses/>.
668 | 
669 |   The GNU General Public License does not permit incorporating your program
670 | into proprietary programs.  If your program is a subroutine library, you
671 | may consider it more useful to permit linking proprietary applications with
672 | the library.  If this is what you want to do, use the GNU Lesser General
673 | Public License instead of this License.  But first, please read
674 | <http://www.gnu.org/philosophy/why-not-lgpl.html>.
675 | 


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