├── .gitignore ├── LICENSE ├── NOTES.md ├── README.md ├── basestationreport.go ├── basestationreport_test.go ├── binarybroadcast.go ├── commonnavigationblock.go ├── coordinates.go ├── coordinates_test.go ├── doc.go ├── examples ├── README.md ├── example-tcp │ ├── README.md │ ├── example-tcp.go │ └── index.html └── example │ ├── README.md │ ├── example.go │ └── nmea-sample.txt ├── helperfunctions.go ├── mmsi.go ├── mmsi_test.go ├── nmeachecksum.go ├── nmeachecksum_test.go ├── positionreport.go ├── positionreport_test.go ├── printmessages.go ├── router.go ├── router_test.go ├── staticdatareport.go ├── staticvoyagedata.go └── staticvoyagedata_test.go /.gitignore: -------------------------------------------------------------------------------- 1 | *~ 2 | *# 3 | nmea-sample.zip -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | GNU GENERAL PUBLIC LICENSE 2 | Version 3, 29 June 2007 3 | 4 | Copyright (C) 2007 Free Software Foundation, Inc. 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. 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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 | 635 | Copyright (C) 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 . 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 | Copyright (C) 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 | . 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 | . 675 | -------------------------------------------------------------------------------- /NOTES.md: -------------------------------------------------------------------------------- 1 | ## TODO 2 | 3 | - Most frequent messages are types 1, 3, 4, 5, 18. We should decode all of them. Currently we decode 1, 3, 4 and 5. 4 | - Find out what ports' reports are. I think they announce when a ship arrives/leaves from port. 5 | - Found out how satellite can be used to capture all AIS. 6 | - Decode some Type 8 messages: 1-11, 1-31 (meteorological) 7 | - DONE: Decode Type 6 DAC-FIDs in order to have some stats. Though Type 6 mesages are very rare it seems. 8 | - DONE: Decode MMSI (includes country or other info as well) 9 | - DONE: Implement a generic router where we feed it messages and it returns message type and payload or error. 10 | - DONE: implement a parser for payloads spanning across 2 or more AIS messages. (tricky: variable length, out of order maybe, maybe we should expire if we don't receive all parts after some time) 11 | 12 | 13 | ## Consider TODO 14 | 15 | These will take much time and maybe there should be some business plan before. In any case we will retain all data, 16 | so if in the future the need arises, we can decode them then. 17 | 18 | - Decode some Type 8 messages: Area Notice, Extended Static and Voyage Related Data, Route Information, etc 19 | - Decode Type 9 messages: search and rescue aircrafts position report 20 | - Decode Type 12 messages: addressed safety related message 21 | - Decode Type 14 messages: broadcast safety related message 22 | - Decode Type 19 messages: Class B extended position report (something between type 18 and type 5) 23 | - Decode Type 21 messages: aid to navigation report 24 | - Decode Type 27 messages: long range Class A position reports 25 | 26 | 27 | ## Notes: 28 | 29 | - Type 1/2/3/4/9/11/18/22 - 168bits - 1 sentence 30 | - Type 5 - 424bits - 2 sentences 31 | - Type 6/8/12/14 - up to 1008bits - up to 5 sentences 32 | - Type 7/13 - 72-168bits - 1 sentence 33 | - Type 10 - 72bits - 1 sentence 34 | - Type 15 - 88-160bits - 1 sentence 35 | - Type 16 - 96 or 144bits - 1 sentence 36 | - Type 17 - 80 to 816bits - up to 4 sentences 37 | - Type 19 - 312bits - 2 sentences 38 | - Type 20 - 72-160bits - 1 sentence 39 | - Type 21 - 272-360bits - 2 sentences 40 | - Type 23 - 160bits - 1 sentence 41 | - Type 24 - 328-336bits - 2 sentences 42 | - Type 25 - up to 168bits - 1 sentence 43 | - Type 26 - 60-1064bits - up to 5 sentences 44 | - Type 27 - 96 or 168bits - 1 sentence 45 | 46 | 47 | ## Stats 48 | 49 | ### Out of 76175 type 1, 3, 4 messages analyzed: 50 | 51 | 71162 / 76175 Ship 52 | 4344 / 76175 Coastal Station 53 | 316 / 76175 Group of ships 54 | 213 / 76175 Aids to navigation 55 | 109 / 76175 SAR —Search and Rescue Aircraft 56 | 20 / 76175 Diver's radio 57 | 01 / 76175 invalid MMSI 58 | 59 | 60 | ### Out of 701088 messages analyzed: 61 | 62 | Type 1: 218359 63 | Type 3: 55917 64 | Type 4: 23239 65 | Type 5: 65672 66 | Type 8: 272742 67 | Type 9: 226 68 | Type 12: 3 69 | Type 13: 5 70 | Type 18: 25117 71 | Type 21: 17380 <- Aid-to-Navigation Report 72 | Type 24: 22428 <- Static Data Report 73 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # aislib # 2 | 3 | A Go library to read AIS sentences and decode AIS messages. 4 | 5 | The most simple example of decoding and printing an AIS message: 6 | 7 | ``` 8 | $ cd examples/example 9 | $ echo '!AIVDM,1,1,,A,14eGrSPP00ncMJTO5C6aBwvP2D0?,0*7A' | go run example.go 10 | === Class A Position Report (1) === 11 | Repeat : 0 12 | MMSI : 316013198 [Ship, Canada] 13 | Nav.Status : Under way using engine 14 | Turn (ROT) : no turn information 15 | Speed (SOG) : 0.0 knots 16 | Accuracy : High accuracy (<10m) 17 | Coordinates : 130°18.9742'W 54°19.2666N 18 | Course (COG) : 237.9° 19 | Heading (HDG): not available 20 | Manuever ind.: not available 21 | RAIM : in use 22 | ``` 23 | 24 | # History 25 | 26 | While I was working for _marine.travel_ —a social site for sea lovers— I wanted to polish my Go 27 | skills. I thought a nice project would be an AIS parser, which later we could use to implement 28 | new functionality for our product. 29 | 30 | I wrote _aislib_ outside my work duties and time, but intended to use it there. Unfortunately 31 | _marine.travel_ didn't make it. Thankfully we are on new, equally exciting adventures now. Since 32 | _aislib_ didn't have any prospects anymore, I asked for permission to release my code under a 33 | permissive license. It was granted and here is the repository. :) 34 | 35 | # Quality and Use Disclaimer 36 | 37 | Please bare in mind that this was my first big-ish project in golang, some poor choices are to 38 | be expected. I am pretty certain that the main functionality is robust though, so if it doesn't 39 | fit your needs, you could use the decoding parts and implement your ideal management parts. 40 | 41 | # Features and State 42 | 43 | Inside the `examples/` directory you will find two examples to get you going. Start with the 44 | simple one, `example.go`. To run: 45 | 46 | $ cat nmea-sample.txt | go run example.go 47 | 48 | **aislib** can decode type 1, 2, 3 (Class A Position Report), 4 (Base Station Report), 49 | 5 (Static Voyage Data), 18 (Class B Position Report) messages. It may also understand type 8 50 | (binary Broadcast) messages, report their respective type and extract the binary payload. 51 | 52 | These are the most common types you will find. If you are interested in extending aislib, it is 53 | worth implementing type 21 and 24 decoding. 54 | 55 | A limitation is multi-sentence messages. Messages that span across AIS sentences will only be 56 | decoded if (a) they come in order and (b) do not interleave with other multi-sentence messages. 57 | 58 | In my experience from capturing AIS data from ais1.shipraiser.net for many hours, the messages 59 | you receive almost always meet these criteria. I think I never saw a sentence parsing failing 60 | due to this restriction. 61 | 62 | # How it Works 63 | 64 | As stated, some poor choices may have been made. 65 | 66 | Each AIS message type has different fields. Thus I implement a router, that receives sentences, 67 | checks their type, their checksum and if the message they carry spans across many sentences 68 | (and it reconstructs the message's payload) and pass back the type and the payload. This work 69 | is done through channels, an incoming channel to the router, to pass AIS sentences and an 70 | outgoing channel to receive message payloads (and types). There is also a second outgoing 71 | channel where you receive the sentences that the router failed to recognize for any reason 72 | (e.g bad checksum or out of order multi-span message). It is useful for debugging. 73 | 74 | So in sort you send AIS sentences into the router and get tuples with AIS message type and 75 | payload. 76 | 77 | You should switch on the message type to the proper decoding function. 78 | 79 | In retrospect, now I know that I could return just the message and let you use type assertion. 80 | This wouldn't change much though, as again you would need a select statement to deal with the 81 | result. 82 | 83 | Check `example.go` to understand how the router and decoding function works. 84 | 85 | # License 86 | 87 | Check `LICENSE` file. In sort it is GPL version 3 or greater. 88 | -------------------------------------------------------------------------------- /basestationreport.go: -------------------------------------------------------------------------------- 1 | // Copyright (c) 2015, Marios Andreopoulos. 2 | // 3 | // This file is part of aislib. 4 | // 5 | // Aislib is free software: you can redistribute it and/or modify 6 | // it under the terms of the GNU General Public License as published by 7 | // the Free Software Foundation, either version 3 of the License, or 8 | // (at your option) any later version. 9 | // 10 | // Aislib is distributed in the hope that it will be useful, 11 | // but WITHOUT ANY WARRANTY; without even the implied warranty of 12 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 | // GNU General Public License for more details. 14 | // 15 | // You should have received a copy of the GNU General Public License 16 | // along with aislib. If not, see . 17 | 18 | package aislib 19 | 20 | import ( 21 | "errors" 22 | "fmt" 23 | "time" 24 | ) 25 | 26 | // A BaseStationReport is a decoded AIS base station report (message type 4) 27 | type BaseStationReport struct { 28 | Repeat uint8 29 | MMSI uint32 30 | Time time.Time 31 | Accuracy bool 32 | Lon float64 33 | Lat float64 34 | EPFD uint8 // Enum type 35 | RAIM bool 36 | Radio uint32 37 | } 38 | 39 | // EPFD Fix Codes 40 | var EpfdFixTypes = [...]string{ 41 | "Undefined", "GPS", "GLONASS", "Combined GPS/GLONASS", "Loran-C", 42 | "Chayka", "Integrated Navigation System", "Surveyed", "Galileo", 43 | "not defined", "not defined", "not defined", "not defined", 44 | "not defined", "not defined", "not defined", 45 | } 46 | 47 | // DecodeBaseStationReport decodes the payload of a Type 4 AIS message 48 | func DecodeBaseStationReport(payload string) (BaseStationReport, error) { 49 | data := []byte(payload) 50 | var m BaseStationReport 51 | 52 | mType := decodeAisChar(data[0]) 53 | if mType != 4 { 54 | return m, errors.New("Message isn't Base Station Report (type 4).") 55 | } 56 | 57 | //m.Repeat = decodeAisChar(data[1]) >> 4 58 | m.Repeat = uint8(bitsToInt(6, 7, data)) 59 | 60 | //m.MMSI = uint32(decodeAisChar(data[1]))<<28>>2 | uint32(decodeAisChar(data[2]))<<20 | 61 | // uint32(decodeAisChar(data[3]))<<14 | uint32(decodeAisChar(data[4]))<<8 | 62 | // uint32(decodeAisChar(data[5]))<<2 | uint32(decodeAisChar(data[6]))>>4 63 | m.MMSI = bitsToInt(8, 37, data) 64 | 65 | m.Time, _ = GetReferenceTime(payload) // Some base stations do not report time, for this case we do not consider it as error 66 | 67 | m.Accuracy = cbnBool(78, data) 68 | 69 | m.Lon, m.Lat = cbnCoordinates(79, data) 70 | 71 | m.EPFD = uint8(bitsToInt(134, 137, data)) 72 | 73 | m.RAIM = cbnBool(148, data) 74 | 75 | m.Radio = bitsToInt(149, 167, data) 76 | return m, nil 77 | } 78 | 79 | // GetReferenceTime takes [the payload of] an AIS Base Station message (type 4) 80 | // and returns the time data of it. It is a separate function from DecodeBaseStationReport 81 | // because it can be useful to set a timeframe for our received AIS messages. 82 | func GetReferenceTime(payload string) (time.Time, error) { 83 | data := []byte(payload) 84 | 85 | //year := uint16(decodeAisChar(data[6]))<<12>>2 | uint16(decodeAisChar(data[7]))<<4 | 86 | // uint16(decodeAisChar(data[8]))>>2 87 | year := bitsToInt(38, 51, data) 88 | if year == 0 { 89 | var t time.Time 90 | return t, errors.New("station doesn't report time") 91 | } 92 | 93 | //month := decodeAisChar(data[8])<<6>>4 | decodeAisChar(data[9])>>4 94 | //day := decodeAisChar(data[9])<<4>>3 | decodeAisChar(data[10])>>5 95 | //hour := decodeAisChar(data[10]) << 3 >> 3 96 | //minute := decodeAisChar(data[11]) 97 | //second := decodeAisChar(data[12]) 98 | month := bitsToInt(52, 55, data) 99 | day := bitsToInt(56, 60, data) 100 | hour := bitsToInt(61, 65, data) 101 | minute := bitsToInt(66, 71, data) 102 | second := bitsToInt(72, 77, data) 103 | 104 | timeString := fmt.Sprintf("%d/%d/%d %d:%d:%d", year, month, day, hour, minute, second) 105 | t, _ := time.Parse("2006/1/2 15:4:5", timeString) 106 | 107 | return t, nil 108 | } 109 | -------------------------------------------------------------------------------- /basestationreport_test.go: -------------------------------------------------------------------------------- 1 | // Copyright (c) 2015, Marios Andreopoulos. 2 | // 3 | // This file is part of aislib. 4 | // 5 | // Aislib is free software: you can redistribute it and/or modify 6 | // it under the terms of the GNU General Public License as published by 7 | // the Free Software Foundation, either version 3 of the License, or 8 | // (at your option) any later version. 9 | // 10 | // Aislib is distributed in the hope that it will be useful, 11 | // but WITHOUT ANY WARRANTY; without even the implied warranty of 12 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 | // GNU General Public License for more details. 14 | // 15 | // You should have received a copy of the GNU General Public License 16 | // along with aislib. If not, see . 17 | 18 | package aislib 19 | 20 | import ( 21 | "fmt" 22 | "testing" 23 | "time" 24 | ) 25 | 26 | func TestDecodeBaseStationReport(t *testing.T) { 27 | caseTime1, _ := time.Parse("2006/1/2 15:4:5", "2015/2/4 0:33:51") 28 | caseTime2, _ := time.Parse("2006/1/2 15:4:5", "2015/2/4 0:33:50") 29 | cases := []struct { 30 | payload string 31 | want BaseStationReport 32 | }{ 33 | { 34 | "402R3KiutR0Qk156V4QQTOA00<0;", 35 | BaseStationReport{ 36 | Repeat: 0, MMSI: 2655087, Time: caseTime1, Accuracy: false, Lon: 15.09579, 37 | Lat: 58.588368333333335, EPFD: 1, RAIM: false, Radio: 49163, 38 | }, 39 | }, 40 | { 41 | "4025boiutR0Qj0qgK0NJbfMRhNA00D3l", "2012/3/14 11:30:14"}, 69 | {"403tDGiuho;P50NJbfMRhNA00D3l") 85 | } 86 | } 87 | -------------------------------------------------------------------------------- /binarybroadcast.go: -------------------------------------------------------------------------------- 1 | // Copyright (c) 2015, Marios Andreopoulos. 2 | // 3 | // This file is part of aislib. 4 | // 5 | // Aislib is free software: you can redistribute it and/or modify 6 | // it under the terms of the GNU General Public License as published by 7 | // the Free Software Foundation, either version 3 of the License, or 8 | // (at your option) any later version. 9 | // 10 | // Aislib is distributed in the hope that it will be useful, 11 | // but WITHOUT ANY WARRANTY; without even the implied warranty of 12 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 | // GNU General Public License for more details. 14 | // 15 | // You should have received a copy of the GNU General Public License 16 | // along with aislib. If not, see . 17 | 18 | package aislib 19 | 20 | import ( 21 | "errors" 22 | ) 23 | 24 | // BinaryBroadcast is a Type 8 message 25 | type BinaryBroadcast struct { 26 | Repeat uint8 27 | MMSI uint32 28 | DAC uint16 29 | FID uint8 30 | Data string 31 | } 32 | 33 | // DecodeBinaryBroadcast decodes [the payload of] an AIS Binary Broadcast message (Type 8) but not its binary payload 34 | func DecodeBinaryBroadcast(payload string) (BinaryBroadcast, error) { 35 | data := []byte(payload) 36 | var m BinaryBroadcast 37 | 38 | mType := decodeAisChar(data[0]) 39 | if mType != 8 { 40 | return m, errors.New("Message isn't Binary Broadcast (type 8).") 41 | } 42 | 43 | m.Repeat = uint8(bitsToInt(6, 7, data)) 44 | 45 | m.MMSI = uint32(bitsToInt(8, 37, data)) 46 | 47 | m.DAC = uint16(bitsToInt(40, 49, data)) 48 | m.FID = uint8(bitsToInt(50, 55, data)) 49 | 50 | m.Data = payload // Data start at bit 56, but this way we simplify our code 51 | 52 | return m, nil 53 | } 54 | 55 | // Some Binary Broadcast types. The list isn't complete but I haven't searched for a better source 56 | var BinaryBroadcastType = map[int]map[int]string{ 57 | 1: { 58 | 11: "Meteorological/Hydrogological Data", 59 | 13: "Fairway closed", 60 | 15: "Extended ship and voyage", 61 | 17: "VTS-Generated/Synthetic targets", 62 | 19: "Marine traffic signals", 63 | 21: "Weather observation from ship", 64 | 22: "Area notice (broadcast)", 65 | 24: "Extended ship and voyage", 66 | 26: "Environmental", 67 | 27: "Route info broadcast", 68 | 29: "Text description broadcast", 69 | 31: "Meteorological and Hydrological", 70 | }, 71 | 200: { 72 | 10: "Ship static and voyage related data", 73 | 23: "EMMA warning report", 74 | 24: "Water levels", 75 | 40: "Signal status", 76 | }, 77 | 316: { 78 | 1: "Weather Station or Wind or Water Level", 79 | 2: "Lockage Order or Estimated Lock Times", 80 | 32: "Seaway Version Message", 81 | }, 82 | 366: { 83 | 1: "Weather Station or Wind or Water Level or PAWS Hydro / Current or PAWS Hydro / Salinity Temp or PAWS Vessel Procession Order", 84 | 2: "Lockage Order or Estimated Lock Times", 85 | 32: "Seaway Version Message", 86 | }, 87 | } 88 | -------------------------------------------------------------------------------- /commonnavigationblock.go: -------------------------------------------------------------------------------- 1 | // Copyright (c) 2015, Marios Andreopoulos. 2 | // 3 | // This file is part of aislib. 4 | // 5 | // Aislib is free software: you can redistribute it and/or modify 6 | // it under the terms of the GNU General Public License as published by 7 | // the Free Software Foundation, either version 3 of the License, or 8 | // (at your option) any later version. 9 | // 10 | // Aislib is distributed in the hope that it will be useful, 11 | // but WITHOUT ANY WARRANTY; without even the implied warranty of 12 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 | // GNU General Public License for more details. 14 | // 15 | // You should have received a copy of the GNU General Public License 16 | // along with aislib. If not, see . 17 | 18 | package aislib 19 | 20 | // Some fields are common across different type of messages. Thus here are functions 21 | // to decode them. 22 | 23 | // cbnCoordinates takes the start of the coordinates block and returns coordinates in 24 | // decimal degrees 25 | func cbnCoordinates(first int, data []byte) (float64, float64) { 26 | lon := float64((int32(bitsToInt(first, first+27, data)) << 4)) / 16 27 | lat := float64((int32(bitsToInt(first+28, first+54, data)) << 5)) / 32 28 | 29 | return CoordinatesMin2Deg(lon, lat) 30 | } 31 | 32 | // cbnSpeed takes the start of the speed block and returns speed in knots or 1023. 33 | func cbnSpeed(first int, data []byte) float32 { 34 | speed := float32(bitsToInt(first, first+9, data)) 35 | if speed < 1022 { 36 | speed /= 10 37 | } 38 | return speed 39 | } 40 | 41 | // cbnBool decodes a bool value 42 | func cbnBool(bit int, data []byte) bool { 43 | if bitsToInt(bit, bit, data) == 1 { 44 | return true 45 | } 46 | return false 47 | } 48 | -------------------------------------------------------------------------------- /coordinates.go: -------------------------------------------------------------------------------- 1 | // Copyright (c) 2015, Marios Andreopoulos. 2 | // 3 | // This file is part of aislib. 4 | // 5 | // Aislib is free software: you can redistribute it and/or modify 6 | // it under the terms of the GNU General Public License as published by 7 | // the Free Software Foundation, either version 3 of the License, or 8 | // (at your option) any later version. 9 | // 10 | // Aislib is distributed in the hope that it will be useful, 11 | // but WITHOUT ANY WARRANTY; without even the implied warranty of 12 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 | // GNU General Public License for more details. 14 | // 15 | // You should have received a copy of the GNU General Public License 16 | // along with aislib. If not, see . 17 | 18 | package aislib 19 | 20 | import ( 21 | "fmt" 22 | "math" 23 | ) 24 | 25 | // CoordinatesMin2Deg translates coordinates (lon, lat) in decimal minutes (×10^4) to decimal degrees. 26 | // AIS data use decimal minutes but decimal degrees (DD) is a more universal format and easier to 27 | // handle. Almost every third party asks for this format. 28 | func CoordinatesMin2Deg(minLon, minLat float64) (float64, float64) { 29 | lonSign := 1.0 30 | latSign := 1.0 31 | 32 | if math.Signbit(minLon) { 33 | minLon = -minLon 34 | lonSign = -1 35 | } 36 | if math.Signbit(minLat) { 37 | minLat = -minLat 38 | latSign = -1 39 | } 40 | 41 | degrees := float64(int(minLon / 600000)) 42 | minutes := float64(minLon-600000*degrees) / 10000 43 | lon := degrees + minutes/60 44 | 45 | degrees = float64(int(minLat / 600000)) 46 | minutes = float64(minLat-600000*degrees) / 10000 47 | lat := degrees + minutes/60 48 | 49 | return lonSign * lon, latSign * lat 50 | } 51 | 52 | // CoordinatesDeg2Human takes coordinates (lon, lat) in decimal degrees (DD), 53 | // formats them as degrees minutes and returns them as string. 54 | func CoordinatesDeg2Human(degLon, degLat float64) string { 55 | lonSign := 1.0 56 | latSign := 1.0 57 | coordinates := "" 58 | 59 | if math.Signbit(degLon) { 60 | degLon = -degLon 61 | lonSign = -1 62 | } 63 | if math.Signbit(degLat) { 64 | degLat = -degLat 65 | latSign = -1 66 | } 67 | 68 | degrees := math.Floor(degLon) 69 | minutes := 60 * (degLon - degrees) 70 | 71 | if degrees > 180 { 72 | coordinates = "longitude not available, " 73 | } else if lonSign > 0 { 74 | coordinates = fmt.Sprintf("%3.0f°%07.4f'%s", degrees, minutes, "E") 75 | } else { 76 | coordinates = fmt.Sprintf("%3.0f°%07.4f'%s", degrees, minutes, "W") 77 | } 78 | 79 | degrees = math.Floor(degLat) 80 | minutes = 60 * (degLat - degrees) 81 | 82 | if degrees > 90 { 83 | coordinates += "latitude not available" 84 | } else if latSign > 0 { 85 | coordinates += fmt.Sprintf(" %3.0f°%07.4f%s", degrees, minutes, "N") 86 | } else { 87 | coordinates += fmt.Sprintf(" %3.0f°%07.4f%s", degrees, minutes, "S") 88 | } 89 | 90 | return coordinates 91 | } 92 | -------------------------------------------------------------------------------- /coordinates_test.go: -------------------------------------------------------------------------------- 1 | // Copyright (c) 2015, Marios Andreopoulos. 2 | // 3 | // This file is part of aislib. 4 | // 5 | // Aislib is free software: you can redistribute it and/or modify 6 | // it under the terms of the GNU General Public License as published by 7 | // the Free Software Foundation, either version 3 of the License, or 8 | // (at your option) any later version. 9 | // 10 | // Aislib is distributed in the hope that it will be useful, 11 | // but WITHOUT ANY WARRANTY; without even the implied warranty of 12 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 | // GNU General Public License for more details. 14 | // 15 | // You should have received a copy of the GNU General Public License 16 | // along with aislib. If not, see . 17 | 18 | package aislib 19 | 20 | import ( 21 | "fmt" 22 | "testing" 23 | ) 24 | 25 | func TestCoordinatesDeg2Human(t *testing.T) { 26 | cases := []struct { 27 | lon, lat float64 28 | want string 29 | }{ 30 | {-3.56725, 53.84251666666667, " 3°34.0350'W 53°50.5510N"}, 31 | {31.130165, -29.784113333333334, " 31°07.8099'E 29°47.0468S"}, 32 | } 33 | for _, c := range cases { 34 | got := CoordinatesDeg2Human(c.lon, c.lat) 35 | if got != c.want { 36 | fmt.Println("Got : ", got) 37 | fmt.Println("Want: ", c.want) 38 | t.Errorf("CoordinatesDeg2Human(lon, lat float64)") 39 | } 40 | } 41 | } 42 | 43 | func ExampleCoordinatesDeg2Human() { 44 | fmt.Println(CoordinatesDeg2Human(-3.56725, 53.84251666666667)) 45 | // Output: 3°34.0350'W 53°50.5510N 46 | } 47 | -------------------------------------------------------------------------------- /doc.go: -------------------------------------------------------------------------------- 1 | // Package ais provides functions and types to work with AIS (Automatic Identification System) 2 | // sentences (radio messages) and messages in AIVDM/AIVDO format. 3 | // 4 | // An AIS sentence is one line, it is the actual radio message. 5 | // An AIS message is the payload that is carried by one or more consecutive AIS sentences. 6 | package aislib 7 | -------------------------------------------------------------------------------- /examples/README.md: -------------------------------------------------------------------------------- 1 | `example.go` is a sample code on how to use the AIS library. 2 | 3 | For a quick demonstration, try to run: 4 | 5 | cat nmea-sample.txt | go run example.go 6 | 7 | Or with live data: 8 | 9 | netcat ais1.shipraiser.net 6492 | go run example.go 10 | 11 | Or with a sentence: 12 | 13 | echo '!AIVDM,1,1,,A,14eGrSPP00ncMJTO5C6aBwvP2D0?,0*7A' | go run example.go 14 | 15 | `example-tcp.go` reads live NMEA data and serves them at 16 | 17 | go run example-tcp.go 18 | -------------------------------------------------------------------------------- /examples/example-tcp/README.md: -------------------------------------------------------------------------------- 1 | `example-tcp.go` reads live NMEA data and plots the ships on a google map, served at . 2 | You can click on the ships to get info about them. 3 | It uses (hardcoded), which unfortunately isn't active anymore. 4 | 5 | If you have another source for AIS data, set it inside `example-tcp.go` and run it: 6 | 7 | go run example-tcp.go 8 | -------------------------------------------------------------------------------- /examples/example-tcp/example-tcp.go: -------------------------------------------------------------------------------- 1 | // Copyright (c) 2015, Marios Andreopoulos. 2 | // 3 | // This file is part of aislib. 4 | // 5 | // Aislib is free software: you can redistribute it and/or modify 6 | // it under the terms of the GNU General Public License as published by 7 | // the Free Software Foundation, either version 3 of the License, or 8 | // (at your option) any later version. 9 | // 10 | // Aislib is distributed in the hope that it will be useful, 11 | // but WITHOUT ANY WARRANTY; without even the implied warranty of 12 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 | // GNU General Public License for more details. 14 | // 15 | // You should have received a copy of the GNU General Public License 16 | // along with aislib. If not, see . 17 | 18 | package main 19 | 20 | import ( 21 | "bufio" 22 | "bytes" 23 | "encoding/json" 24 | "errors" 25 | "fmt" 26 | "log" 27 | "net" 28 | "net/http" 29 | "strconv" 30 | "time" 31 | 32 | ais "github.com/andmarios/aislib" 33 | ) 34 | 35 | // Here are saved as JSON string the ships seen in the last 5-second period. 36 | var serveJSON string 37 | 38 | type shipData struct { 39 | Data ais.ClassAPositionReport 40 | Human string 41 | } 42 | 43 | func main() { 44 | 45 | // Create an AIS router process to decode radio sentences 46 | send := make(chan string, 1024) 47 | receive := make(chan ais.Message, 1024) 48 | failed := make(chan ais.FailedSentence, 1024) 49 | go ais.Router(send, receive, failed) 50 | 51 | // Create a handler-process that reads messages from router, decodes and saves the payload 52 | seen := make(map[uint32]shipData) 53 | proceed := make(chan bool) 54 | go func() { 55 | var message ais.Message 56 | var problematic ais.FailedSentence 57 | for { 58 | select { 59 | case message = <-receive: 60 | if message.Type >= 1 && message.Type <= 3 { 61 | m, _ := ais.DecodeClassAPositionReport(message.Payload) 62 | seen[m.MMSI] = shipData{m, m.String()} 63 | } 64 | case problematic = <-failed: 65 | log.Println(problematic) 66 | case _ = <-proceed: // Unbuffered channel used for synchronization (as mutex for [seen]) 67 | <-proceed 68 | } 69 | } 70 | }() 71 | 72 | // Create a process that every five seconds refreshes [serveJSON] with new data 73 | go func() { 74 | var jsonBuf bytes.Buffer 75 | for _ = range time.Tick(5 * time.Second) { 76 | proceed <- true 77 | ships := seen 78 | seen = make(map[uint32]shipData) 79 | proceed <- true 80 | for _, s := range ships { 81 | j, _ := json.Marshal(s) 82 | jsonBuf.Write(j) 83 | jsonBuf.WriteString(",") 84 | } 85 | length := len(jsonBuf.String()) 86 | if length > 10 { 87 | serveJSON = "[" + jsonBuf.String()[:length-1] + "]" 88 | jsonBuf.Reset() 89 | } else { 90 | serveJSON = "[]" 91 | } 92 | } 93 | }() 94 | 95 | // Connect to a remote AIS server. Read AIS sentences and forward them to the AIS router. 96 | // If connection drops wait and reconnect. 97 | remote := "ais1.shipraiser.net:6492" 98 | go func() { 99 | sleep := 10 // How many seconds to sleep after a timeout 100 | sleepD := time.Duration(sleep) * time.Second 101 | for { 102 | serverAddr, err := net.ResolveTCPAddr("tcp", remote) 103 | if err != nil { 104 | log.Println(err, errors.New("(retrying in "+strconv.Itoa(sleep)+" seconds)")) 105 | time.Sleep(sleepD) 106 | continue 107 | } 108 | conn, err := net.DialTCP("tcp", nil, serverAddr) 109 | if err != nil { 110 | log.Println(err, errors.New("(retrying in "+strconv.Itoa(sleep)+" seconds)")) 111 | time.Sleep(sleepD) 112 | continue 113 | } 114 | defer conn.Close() 115 | 116 | connbuf := bufio.NewScanner(conn) 117 | connbuf.Split(bufio.ScanLines) 118 | for connbuf.Scan() { 119 | send <- connbuf.Text() 120 | conn.SetReadDeadline(time.Now().Add(15 * time.Second)) 121 | } 122 | log.Println(remote + ": connection broken (retrying in " + strconv.Itoa(sleep) + " seconds)") 123 | time.Sleep(sleepD) 124 | } 125 | }() 126 | 127 | // Create a server to listen for files/data requests 128 | http.HandleFunc("/data", dataHandler) 129 | http.Handle("/", http.FileServer(http.Dir("."))) 130 | http.ListenAndServe(":8080", nil) 131 | 132 | } 133 | 134 | // Function to serve the ships JSON string 135 | func dataHandler(w http.ResponseWriter, r *http.Request) { 136 | fmt.Fprintf(w, "%s", serveJSON) 137 | } 138 | -------------------------------------------------------------------------------- /examples/example-tcp/index.html: -------------------------------------------------------------------------------- 1 | 2 | 7 | 8 | 9 | 10 | 11 | 52 | 54 | 57 | 181 | 182 | 183 |
    184 |
    • 185 |
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MT Traffic

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page kindly borrowed by dump1090
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Click on a ship for info.

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195 | 196 | 197 | -------------------------------------------------------------------------------- /examples/example/README.md: -------------------------------------------------------------------------------- 1 | `example.go` is a sample code on how to use the AIS library. 2 | 3 | For a quick demonstration, try to run: 4 | 5 | cat nmea-sample.txt | go run example.go 6 | 7 | Or with live data: 8 | 9 | netcat ais1.shipraiser.net 6492 | go run example.go 10 | 11 | Or with a sentence: 12 | 13 | echo '!AIVDM,1,1,,A,14eGrSPP00ncMJTO5C6aBwvP2D0?,0*7A' | go run example.go 14 | -------------------------------------------------------------------------------- /examples/example/example.go: -------------------------------------------------------------------------------- 1 | // Copyright (c) 2015, Marios Andreopoulos. 2 | // 3 | // This file is part of aislib. 4 | // 5 | // Aislib is free software: you can redistribute it and/or modify 6 | // it under the terms of the GNU General Public License as published by 7 | // the Free Software Foundation, either version 3 of the License, or 8 | // (at your option) any later version. 9 | // 10 | // Aislib is distributed in the hope that it will be useful, 11 | // but WITHOUT ANY WARRANTY; without even the implied warranty of 12 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 | // GNU General Public License for more details. 14 | // 15 | // You should have received a copy of the GNU General Public License 16 | // along with aislib. If not, see . 17 | 18 | package main 19 | 20 | import ( 21 | "bufio" 22 | "fmt" 23 | "log" 24 | "os" 25 | 26 | ais "github.com/andmarios/aislib" 27 | ) 28 | 29 | func main() { 30 | in := bufio.NewScanner(os.Stdin) 31 | in.Split(bufio.ScanLines) 32 | 33 | send := make(chan string, 1024*8) 34 | receive := make(chan ais.Message, 1024*8) 35 | failed := make(chan ais.FailedSentence, 1024*8) 36 | 37 | done := make(chan bool) 38 | 39 | go ais.Router(send, receive, failed) 40 | 41 | go func() { 42 | var message ais.Message 43 | var problematic ais.FailedSentence 44 | for { 45 | select { 46 | case message = <-receive: 47 | switch message.Type { 48 | case 1, 2, 3: 49 | t, _ := ais.DecodeClassAPositionReport(message.Payload) 50 | fmt.Println(t) 51 | case 4: 52 | t, _ := ais.DecodeBaseStationReport(message.Payload) 53 | fmt.Println(t) 54 | case 5: 55 | t, _ := ais.DecodeStaticVoyageData(message.Payload) 56 | fmt.Println(t) 57 | case 8: 58 | t, _ := ais.DecodeBinaryBroadcast(message.Payload) 59 | fmt.Println(t) 60 | case 18: 61 | t, _ := ais.DecodeClassBPositionReport(message.Payload) 62 | fmt.Println(t) 63 | case 255: 64 | done <- true 65 | default: 66 | fmt.Printf("=== Message Type %2d ===\n", message.Type) 67 | fmt.Printf(" Unsupported type \n\n") 68 | } 69 | case problematic = <-failed: 70 | log.Println(problematic) 71 | } 72 | } 73 | }() 74 | 75 | for in.Scan() { 76 | send <- in.Text() 77 | } 78 | close(send) 79 | <-done 80 | } 81 | -------------------------------------------------------------------------------- /examples/example/nmea-sample.txt: -------------------------------------------------------------------------------- 1 | !AIVDM,1,1,,B,38uP:WfuAO9PWL089D,0*31 3 | !AIVDM,1,1,,A,1=Rrj`QP?w4?wv0l1?,0*0B 4 | !AIVDM,1,1,,B,B3ujWF0000DdVU8O:1H03wi5oP06,0*5C 5 | !AIVDM,1,1,,A,36K2DrP02KabIF2CjCVCijnN00RP,0*15 6 | !AIVDM,1,1,,A,13n@oD0PB@0IRqvQj@W;EppH088t19uvPT,0*3E 7 | !AIVDM,1,1,,B,4025;PAuho;N>0NJbfMRhNA00D3l,0*66 8 | !AIVDM,2,1,,A,13prNl0oKaCLIdeFlrc0,2*08 15 | !AIVDM,2,1,2,A,53uJur01rN?U<9@T001@tI@F000000000000000l0pA444mm?:1km1@S,0*5C 16 | !AIVDM,2,2,2,A,lQp000000000000,2*5B 17 | !AIVDM,2,1,5,B,802R5Ph0GhOe. 17 | 18 | package aislib 19 | 20 | import "strings" 21 | 22 | // decodeAisChar takes a byte a returns the six bit field of AIS data. 23 | func decodeAisChar(character byte) byte { 24 | character -= 48 25 | if character > 40 { 26 | character -= 8 27 | } 28 | return character 29 | } 30 | 31 | // MessageType returns the type of an AIS message 32 | func MessageType(payload string) uint8 { 33 | data := []byte(payload[:1]) 34 | return decodeAisChar(data[0]) 35 | } 36 | 37 | // bitsToInt extracts certain bits from a payload. 38 | // Payload consists of six bit packets, each one armored in one byte. 39 | // The function seems simple enough but took me some hours to figure out. 40 | // It is necessary since this is the most frequent part of the message decoding process 41 | // and one can only write so many binary operations. We sacrifice performance a bit to 42 | // significantly ease development. :-/ 43 | func bitsToInt(first, last int, payload []byte) uint32 { 44 | size := uint(last - first) // Bit fields start at 0 45 | processed, remain := uint(0), uint(0) 46 | result, temp := uint32(0), uint32(0) 47 | 48 | from := first / 6 49 | forTimes := last/6 - from 50 | 51 | if len(payload)*6 < last+1 { // There are strange messages out there, this seems to be what decoders do 52 | return 0 53 | } 54 | for i := 0; i <= forTimes; i++ { 55 | // Instead of calling decodeAisChar we do the calculation manually here for speed. 56 | temp = uint32(payload[from+i]) - 48 57 | if temp > 40 { 58 | temp -= 8 59 | } 60 | 61 | // Depending on which byte in sequence we processing, do the appropriate shifts. 62 | if i == 0 { // For the first byte we (may) have to clean leftmost bits and shift to position 63 | remain = uint(first % 6) 64 | processed = 5 - remain 65 | temp = temp << (31 - processed) >> (31 - size) 66 | } else if i < forTimes { // For middle bytes we only shift to position 67 | processed = processed + 6 68 | temp = temp << (size - processed) 69 | } else { // For last byte we (may) clear rightmost bits 70 | remain = uint(last%6) + 1 71 | temp = temp >> (6 - remain) 72 | } 73 | result = result | temp 74 | } 75 | return result 76 | } 77 | 78 | // bitsToString decodes text from an AIS payload. Text is packed in six bit ASCII 79 | func bitsToString(first, last int, payload []byte) string { 80 | length := (last - first + 1) / 6 // How many characters we expect 81 | start := first / 6 // At which byte the first character starts 82 | var text [64]byte // Not sure which the maximum text field size is, but this should be enough 83 | char := uint8(0) 84 | 85 | // Some times we get truncated text fields. Since text fields have constant size, 86 | // it is frequent that they aren't fully occupied. Transmitters use this to send shorter messages. 87 | // We should handle this gracefully, adjusting the length of the text we expect to read. 88 | if len(payload)*6 < last+1 { 89 | if len(payload)*6 < first+5 { // Haven't seen this case yet (text field missing) but better be prepared 90 | return "" 91 | } 92 | // Do not simplify this. It uses the uint type rounding method to get correct results 93 | length = (len(payload)*6 - first) / 6 94 | } 95 | 96 | remain := first % 6 97 | 98 | // In this if/else there is some code duplication but I think the speed enhancement is worth it. 99 | // The other way around would need 2*length branches. Now we have only 2. 100 | // decodeAisChar function should be safe to use here since we check the payload's length 101 | if remain < 6 { 102 | shiftLeftMost := uint8(remain + 2) 103 | shiftRightMost := uint8(6 - remain) 104 | for i := 0; i < length; i++ { 105 | char = decodeAisChar(payload[start+i])<>2 | 106 | decodeAisChar(payload[start+i+1])>>shiftRightMost 107 | if char < 32 { 108 | char += 64 109 | } 110 | text[i] = char 111 | } 112 | } else { 113 | for i := 0; i < length; i++ { 114 | char = decodeAisChar(payload[start+i]) 115 | if char < 32 { 116 | char += 64 117 | } 118 | text[i] = char 119 | } 120 | } 121 | 122 | // We convert to string and trim the righmost spaces and @ according to the format specs. 123 | return strings.TrimRight(string(text[:length]), "@ ") 124 | } 125 | -------------------------------------------------------------------------------- /mmsi.go: -------------------------------------------------------------------------------- 1 | // Copyright (c) 2015, Marios Andreopoulos. 2 | // 3 | // This file is part of aislib. 4 | // 5 | // Aislib is free software: you can redistribute it and/or modify 6 | // it under the terms of the GNU General Public License as published by 7 | // the Free Software Foundation, either version 3 of the License, or 8 | // (at your option) any later version. 9 | // 10 | // Aislib is distributed in the hope that it will be useful, 11 | // but WITHOUT ANY WARRANTY; without even the implied warranty of 12 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 | // GNU General Public License for more details. 14 | // 15 | // You should have received a copy of the GNU General Public License 16 | // along with aislib. If not, see . 17 | 18 | package aislib 19 | 20 | // Contains MMSI owners' descriptions. Currently not used anywhere 21 | var MmsiCodes = [...]string{ 22 | "Ship", "Coastal Station", "Group of ships", "SAR —Search and Rescue Aircraft", 23 | "Diver's radio", "Aids to navigation", "Auxiliary craft associated with parent ship", 24 | "AIS SART —Search and Rescue Transmitter", "MOB —Man Overboard Device", 25 | "EPIRB —Emergency Position Indicating Radio Beacon", "Invalid MMSI", 26 | } 27 | 28 | // DecodeMMSI returns a string with the type of the owner of the MMSI and its country 29 | // Some MMSIs aren't valid. There is some more information in some MMSIs (the satellite 30 | // equipment of the ship). We may add them in the future. 31 | // Have a look at http://en.wikipedia.org/wiki/Maritime_Mobile_Service_Identity 32 | func DecodeMMSI(m uint32) string { 33 | owner := "" 34 | country := "" 35 | mid := uint32(1000) 36 | 37 | // Current intervals: 38 | // [0 00999999][010000000 099999999][100000000 199999999][200000000 799999999] 39 | // [800000000 899999999]...[970000000 970999999]...[972000000 972999999]... 40 | // [974000000 974999999]...[98000000 98999999][99000000 999999999] 41 | switch { 42 | case m >= 200000000 && m < 800000000: 43 | mid = m / 1000000 44 | owner = "Ship" 45 | case m <= 9999999: 46 | mid = m / 10000 47 | owner = "Coastal Station" 48 | case m <= 99999999: 49 | mid = m / 100000 50 | owner = "Group of ships" 51 | case m <= 199999999: 52 | mid = m/1000 - 111000 53 | owner = "SAR —Search and Rescue Aircraft" 54 | case m < 900000000: 55 | mid = m/100000 - 8000 56 | owner = "Diver's radio" 57 | case m >= 990000000 && m < 1000000000: 58 | mid = m/10000 - 99000 59 | owner = "Aids to navigation" 60 | case m >= 980000000 && m < 990000000: 61 | mid = m/10000 - 98000 62 | owner = "Auxiliary craft associated with parent ship" 63 | case m >= 970000000 && m < 970999999: 64 | mid = m/1000 - 970000 65 | owner = "AIS SART —Search and Rescue Transmitter" 66 | case m >= 972000000 && m < 972999999: 67 | owner = "MOB —Man Overboard Device" 68 | case m >= 974000000 && m < 974999999: 69 | owner = "EPIRB —Emergency Position Indicating Radio Beacon" 70 | default: 71 | owner = "Invalid MMSI" 72 | } 73 | 74 | if mid < 1000 { 75 | country = Mid[int(mid)] 76 | if country == "" { 77 | country = "Unknown Country ID" 78 | } 79 | return owner + ", " + country 80 | } 81 | return owner 82 | } 83 | 84 | // Maritime Identification Digits, have a look at http://www.itu.int/online/mms/glad/cga_mids.sh?lang=en 85 | var Mid = map[int]string{ 86 | 201: "Albania (Republic of)", 87 | 202: "Andorra (Principality of)", 88 | 203: "Austria", 89 | 204: "Azores - Portugal", 90 | 205: "Belgium", 91 | 206: "Belarus (Republic of)", 92 | 207: "Bulgaria (Republic of)", 93 | 208: "Vatican City State", 94 | 209: "Cyprus (Republic of)", 95 | 210: "Cyprus (Republic of)", 96 | 211: "Germany (Federal Republic of)", 97 | 212: "Cyprus (Republic of)", 98 | 213: "Georgia", 99 | 214: "Moldova (Republic of)", 100 | 215: "Malta", 101 | 216: "Armenia (Republic of)", 102 | 218: "Germany (Federal Republic of)", 103 | 219: "Denmark", 104 | 220: "Denmark", 105 | 224: "Spain", 106 | 225: "Spain", 107 | 226: "France", 108 | 227: "France", 109 | 228: "France", 110 | 229: "Malta", 111 | 230: "Finland", 112 | 231: "Faroe Islands - Denmark", 113 | 232: "United Kingdom of Great Britain and Northern Ireland", 114 | 233: "United Kingdom of Great Britain and Northern Ireland", 115 | 234: "United Kingdom of Great Britain and Northern Ireland", 116 | 235: "United Kingdom of Great Britain and Northern Ireland", 117 | 236: "Gibraltar - United Kingdom of Great Britain and Northern Ireland", 118 | 237: "Greece", 119 | 238: "Croatia (Republic of)", 120 | 239: "Greece", 121 | 240: "Greece", 122 | 241: "Greece", 123 | 242: "Morocco (Kingdom of)", 124 | 243: "Hungary", 125 | 244: "Netherlands (Kingdom of the)", 126 | 245: "Netherlands (Kingdom of the)", 127 | 246: "Netherlands (Kingdom of the)", 128 | 247: "Italy", 129 | 248: "Malta", 130 | 249: "Malta", 131 | 250: "Ireland", 132 | 251: "Iceland", 133 | 252: "Liechtenstein (Principality of)", 134 | 253: "Luxembourg", 135 | 254: "Monaco (Principality of)", 136 | 255: "Madeira - Portugal", 137 | 256: "Malta", 138 | 257: "Norway", 139 | 258: "Norway", 140 | 259: "Norway", 141 | 261: "Poland (Republic of)", 142 | 262: "Montenegro", 143 | 263: "Portugal", 144 | 264: "Romania", 145 | 265: "Sweden", 146 | 266: "Sweden", 147 | 267: "Slovak Republic", 148 | 268: "San Marino (Republic of)", 149 | 269: "Switzerland (Confederation of)", 150 | 270: "Czech Republic", 151 | 271: "Turkey", 152 | 272: "Ukraine", 153 | 273: "Russian Federation", 154 | 274: "The Former Yugoslav Republic of Macedonia", 155 | 275: "Latvia (Republic of)", 156 | 276: "Estonia (Republic of)", 157 | 277: "Lithuania (Republic of)", 158 | 278: "Slovenia (Republic of)", 159 | 279: "Serbia (Republic of)", 160 | 301: "Anguilla - United Kingdom of Great Britain and Northern Ireland", 161 | 303: "Alaska (State of) - United States of America", 162 | 304: "Antigua and Barbuda", 163 | 305: "Antigua and Barbuda", 164 | 306: "Curacao, Sint Maarten (Dutch part), Bonaire, Sint Eustatius and Saba - Netherlands (Kingdom of the)", 165 | 307: "Aruba - Netherlands (Kingdom of the)", 166 | 308: "Bahamas (Commonwealth of the)", 167 | 309: "Bahamas (Commonwealth of the)", 168 | 310: "Bermuda - United Kingdom of Great Britain and Northern Ireland", 169 | 311: "Bahamas (Commonwealth of the)", 170 | 312: "Belize", 171 | 314: "Barbados", 172 | 316: "Canada", 173 | 319: "Cayman Islands - United Kingdom of Great Britain and Northern Ireland", 174 | 321: "Costa Rica", 175 | 323: "Cuba", 176 | 325: "Dominica (Commonwealth of)", 177 | 327: "Dominican Republic", 178 | 329: "Guadeloupe (French Department of) - France", 179 | 330: "Grenada", 180 | 331: "Greenland - Denmark", 181 | 332: "Guatemala (Republic of)", 182 | 334: "Honduras (Republic of)", 183 | 336: "Haiti (Republic of)", 184 | 338: "United States of America", 185 | 339: "Jamaica", 186 | 341: "Saint Kitts and Nevis (Federation of)", 187 | 343: "Saint Lucia", 188 | 345: "Mexico", 189 | 347: "Martinique (French Department of) - France", 190 | 348: "Montserrat - United Kingdom of Great Britain and Northern Ireland", 191 | 350: "Nicaragua", 192 | 351: "Panama (Republic of)", 193 | 352: "Panama (Republic of)", 194 | 353: "Panama (Republic of)", 195 | 354: "Panama (Republic of)", 196 | 355: " - ", 197 | 356: " - ", 198 | 357: " - ", 199 | 358: "Puerto Rico - United States of America", 200 | 359: "El Salvador (Republic of)", 201 | 361: "Saint Pierre and Miquelon (Territorial Collectivity of) - France", 202 | 362: "Trinidad and Tobago", 203 | 364: "Turks and Caicos Islands - United Kingdom of Great Britain and Northern Ireland", 204 | 366: "United States of America", 205 | 367: "United States of America", 206 | 368: "United States of America", 207 | 369: "United States of America", 208 | 370: "Panama (Republic of)", 209 | 371: "Panama (Republic of)", 210 | 372: "Panama (Republic of)", 211 | 373: "Panama (Republic of)", 212 | 375: "Saint Vincent and the Grenadines", 213 | 376: "Saint Vincent and the Grenadines", 214 | 377: "Saint Vincent and the Grenadines", 215 | 378: "British Virgin Islands - United Kingdom of Great Britain and Northern Ireland", 216 | 379: "United States Virgin Islands - United States of America", 217 | 401: "Afghanistan", 218 | 403: "Saudi Arabia (Kingdom of)", 219 | 405: "Bangladesh (People's Republic of)", 220 | 408: "Bahrain (Kingdom of)", 221 | 410: "Bhutan (Kingdom of)", 222 | 412: "China (People's Republic of)", 223 | 413: "China (People's Republic of)", 224 | 414: "China (People's Republic of)", 225 | 416: "Taiwan (Province of China) - China (People's Republic of)", 226 | 417: "Sri Lanka (Democratic Socialist Republic of)", 227 | 419: "India (Republic of)", 228 | 422: "Iran (Islamic Republic of)", 229 | 423: "Azerbaijan (Republic of)", 230 | 425: "Iraq (Republic of)", 231 | 428: "Israel (State of)", 232 | 431: "Japan", 233 | 432: "Japan", 234 | 434: "Turkmenistan", 235 | 436: "Kazakhstan (Republic of)", 236 | 437: "Uzbekistan (Republic of)", 237 | 438: "Jordan (Hashemite Kingdom of)", 238 | 440: "Korea (Republic of)", 239 | 441: "Korea (Republic of)", 240 | 443: "State of Palestine (In accordance with Resolution 99 Rev. Guadalajara, 2010)", 241 | 445: "Democratic People's Republic of Korea", 242 | 447: "Kuwait (State of)", 243 | 450: "Lebanon", 244 | 451: "Kyrgyz Republic", 245 | 453: "Macao (Special Administrative Region of China) - China (People's Republic of)", 246 | 455: "Maldives (Republic of)", 247 | 457: "Mongolia", 248 | 459: "Nepal (Federal Democratic Republic of)", 249 | 461: "Oman (Sultanate of)", 250 | 463: "Pakistan (Islamic Republic of)", 251 | 466: "Qatar (State of)", 252 | 468: "Syrian Arab Republic", 253 | 470: "United Arab Emirates", 254 | 472: "Tajikistan (Republic of)", 255 | 473: "Yemen (Republic of)", 256 | 475: "Yemen (Republic of)", 257 | 477: "Hong Kong (Special Administrative Region of China) - China (People's Republic of)", 258 | 478: "Bosnia and Herzegovina", 259 | 501: "Adelie Land - France", 260 | 503: "Australia", 261 | 506: "Myanmar (Union of)", 262 | 508: "Brunei Darussalam", 263 | 510: "Micronesia (Federated States of)", 264 | 511: "Palau (Republic of)", 265 | 512: "New Zealand", 266 | 514: "Cambodia (Kingdom of)", 267 | 515: "Cambodia (Kingdom of)", 268 | 516: "Christmas Island (Indian Ocean) - Australia", 269 | 518: "Cook Islands - New Zealand", 270 | 520: "Fiji (Republic of)", 271 | 523: "Cocos (Keeling) Islands - Australia", 272 | 525: "Indonesia (Republic of)", 273 | 529: "Kiribati (Republic of)", 274 | 531: "Lao People's Democratic Republic", 275 | 533: "Malaysia", 276 | 536: "Northern Mariana Islands (Commonwealth of the) - United States of America", 277 | 538: "Marshall Islands (Republic of the)", 278 | 540: "New Caledonia - France", 279 | 542: "Niue - New Zealand", 280 | 544: "Nauru (Republic of)", 281 | 546: "French Polynesia - France", 282 | 548: "Philippines (Republic of the)", 283 | 553: "Papua New Guinea", 284 | 555: "Pitcairn Island - United Kingdom of Great Britain and Northern Ireland", 285 | 557: "Solomon Islands", 286 | 559: "American Samoa - United States of America", 287 | 561: "Samoa (Independent State of)", 288 | 563: "Singapore (Republic of)", 289 | 564: "Singapore (Republic of)", 290 | 565: "Singapore (Republic of)", 291 | 566: "Singapore (Republic of)", 292 | 567: "Thailand", 293 | 570: "Tonga (Kingdom of)", 294 | 572: "Tuvalu", 295 | 574: "Viet Nam (Socialist Republic of)", 296 | 576: "Vanuatu (Republic of)", 297 | 577: "Vanuatu (Republic of)", 298 | 578: "Wallis and Futuna Islands - France", 299 | 601: "South Africa (Republic of)", 300 | 603: "Angola (Republic of)", 301 | 605: "Algeria (People's Democratic Republic of)", 302 | 607: "Saint Paul and Amsterdam Islands - France", 303 | 608: "Ascension Island - United Kingdom of Great Britain and Northern Ireland", 304 | 609: "Burundi (Republic of)", 305 | 610: "Benin (Republic of)", 306 | 611: "Botswana (Republic of)", 307 | 612: "Central African Republic", 308 | 613: "Cameroon (Republic of)", 309 | 615: "Congo (Republic of the)", 310 | 616: "Comoros (Union of the)", 311 | 617: "Cabo Verde (Republic of)", 312 | 618: "Crozet Archipelago - France", 313 | 619: "Cote d'Ivoire (Republic of)", 314 | 620: "Comoros (Union of the)", 315 | 621: "Djibouti (Republic of)", 316 | 622: "Egypt (Arab Republic of)", 317 | 624: "Ethiopia (Federal Democratic Republic of)", 318 | 625: "Eritrea", 319 | 626: "Gabonese Republic", 320 | 627: "Ghana", 321 | 629: "Gambia (Republic of the)", 322 | 630: "Guinea-Bissau (Republic of)", 323 | 631: "Equatorial Guinea (Republic of)", 324 | 632: "Guinea (Republic of)", 325 | 633: "Burkina Faso", 326 | 634: "Kenya (Republic of)", 327 | 635: "Kerguelen Islands - France", 328 | 636: "Liberia (Republic of)", 329 | 637: "Liberia (Republic of)", 330 | 638: "South Sudan (Republic of)", 331 | 642: "Libya", 332 | 644: "Lesotho (Kingdom of)", 333 | 645: "Mauritius (Republic of)", 334 | 647: "Madagascar (Republic of)", 335 | 649: "Mali (Republic of)", 336 | 650: "Mozambique (Republic of)", 337 | 654: "Mauritania (Islamic Republic of)", 338 | 655: "Malawi", 339 | 656: "Niger (Republic of the)", 340 | 657: "Nigeria (Federal Republic of)", 341 | 659: "Namibia (Republic of)", 342 | 660: "Reunion (French Department of) - France", 343 | 661: "Rwanda (Republic of)", 344 | 662: "Sudan (Republic of the)", 345 | 663: "Senegal (Republic of)", 346 | 664: "Seychelles (Republic of)", 347 | 665: "Saint Helena - United Kingdom of Great Britain and Northern Ireland", 348 | 666: "Somalia (Federal Republic of)", 349 | 667: "Sierra Leone", 350 | 668: "Sao Tome and Principe (Democratic Republic of)", 351 | 669: "Swaziland (Kingdom of)", 352 | 670: "Chad (Republic of)", 353 | 671: "Togolese Republic", 354 | 672: "Tunisia", 355 | 674: "Tanzania (United Republic of)", 356 | 675: "Uganda (Republic of)", 357 | 676: "Democratic Republic of the Congo", 358 | 677: "Tanzania (United Republic of)", 359 | 678: "Zambia (Republic of)", 360 | 679: "Zimbabwe (Republic of)", 361 | 701: "Argentine Republic", 362 | 710: "Brazil (Federative Republic of)", 363 | 720: "Bolivia (Plurinational State of)", 364 | 725: "Chile", 365 | 730: "Colombia (Republic of)", 366 | 735: "Ecuador", 367 | 740: "Falkland Islands (Malvinas) - United Kingdom of Great Britain and Northern Ireland", 368 | 745: "Guiana (French Department of) - France", 369 | 750: "Guyana", 370 | 755: "Paraguay (Republic of)", 371 | 760: "Peru", 372 | 765: "Suriname (Republic of)", 373 | 770: "Uruguay (Eastern Republic of)", 374 | } 375 | -------------------------------------------------------------------------------- /mmsi_test.go: -------------------------------------------------------------------------------- 1 | // Copyright (c) 2015, Marios Andreopoulos. 2 | // 3 | // This file is part of aislib. 4 | // 5 | // Aislib is free software: you can redistribute it and/or modify 6 | // it under the terms of the GNU General Public License as published by 7 | // the Free Software Foundation, either version 3 of the License, or 8 | // (at your option) any later version. 9 | // 10 | // Aislib is distributed in the hope that it will be useful, 11 | // but WITHOUT ANY WARRANTY; without even the implied warranty of 12 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 | // GNU General Public License for more details. 14 | // 15 | // You should have received a copy of the GNU General Public License 16 | // along with aislib. If not, see . 17 | 18 | package aislib 19 | 20 | import ( 21 | "fmt" 22 | "testing" 23 | ) 24 | 25 | // I didn't found a MMSI decoder, so this test is verified only by me 26 | func TestDecodeMMSI(t *testing.T) { 27 | cases := []struct { 28 | MMSI uint32 29 | reference string 30 | }{ 31 | {227006760, "Ship, France"}, 32 | {2573425, "Coastal Station, Norway"}, 33 | {25634906, "Group of ships, Malta"}, 34 | {842517724, "Diver's radio, Iraq (Republic of)"}, 35 | {992351000, "Aids to navigation, United Kingdom of Great Britain and Northern Ireland"}, 36 | {1000010000, "Invalid MMSI"}, 37 | {972345000, "MOB —Man Overboard Device"}, 38 | {970241023, "AIS SART —Search and Rescue Transmitter, Greece"}, 39 | {971356034, "Invalid MMSI"}, 40 | } 41 | for _, c := range cases { 42 | got := DecodeMMSI(c.MMSI) 43 | if got != c.reference { 44 | fmt.Println("Got : ", got) 45 | fmt.Println("Want: ", c.reference) 46 | t.Errorf("DecodeMMSI(m uint32)") 47 | } 48 | } 49 | } 50 | 51 | func BenchmarkDecodeMMSI(b *testing.B) { 52 | for i := 0; i < b.N; i++ { 53 | switch { 54 | case i%116 < 108: 55 | DecodeMMSI(316013198) 56 | case i%116 < 115: 57 | DecodeMMSI(002241076) 58 | default: 59 | DecodeMMSI(992351000) 60 | } 61 | } 62 | } 63 | -------------------------------------------------------------------------------- /nmeachecksum.go: -------------------------------------------------------------------------------- 1 | // Copyright (c) 2015, Marios Andreopoulos. 2 | // 3 | // This file is part of aislib. 4 | // 5 | // Aislib is free software: you can redistribute it and/or modify 6 | // it under the terms of the GNU General Public License as published by 7 | // the Free Software Foundation, either version 3 of the License, or 8 | // (at your option) any later version. 9 | // 10 | // Aislib is distributed in the hope that it will be useful, 11 | // but WITHOUT ANY WARRANTY; without even the implied warranty of 12 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 | // GNU General Public License for more details. 14 | // 15 | // You should have received a copy of the GNU General Public License 16 | // along with aislib. If not, see . 17 | 18 | package aislib 19 | 20 | import "encoding/hex" 21 | 22 | // Nmea183ChecksumCheck performs a checksum check for NMEA183 sentences. 23 | // AIS messages are NMEA183 encoded. 24 | func Nmea183ChecksumCheck(sentence string) bool { 25 | length := len(sentence) 26 | if length < 5 { // Sentence isn't long enough to have a csum, avoid bounds out of range 27 | return false 28 | } 29 | 30 | // Read the checksum from the AIS sentence 31 | csum, err := hex.DecodeString(sentence[length-2:]) 32 | if err != nil { 33 | return false 34 | } 35 | 36 | // The checksum is calculated from the whole sentence except 37 | // the first and last three characters 38 | bline := []byte(sentence[1 : length-3]) 39 | ccsum := bline[0] 40 | // The checksum is calculated by XOR'ing all the characters 41 | for i := 1; i < len(bline); i++ { 42 | ccsum ^= bline[i] 43 | } 44 | 45 | if csum[0] == ccsum { 46 | return true 47 | } 48 | return false 49 | } 50 | -------------------------------------------------------------------------------- /nmeachecksum_test.go: -------------------------------------------------------------------------------- 1 | // Copyright (c) 2015, Marios Andreopoulos. 2 | // 3 | // This file is part of aislib. 4 | // 5 | // Aislib is free software: you can redistribute it and/or modify 6 | // it under the terms of the GNU General Public License as published by 7 | // the Free Software Foundation, either version 3 of the License, or 8 | // (at your option) any later version. 9 | // 10 | // Aislib is distributed in the hope that it will be useful, 11 | // but WITHOUT ANY WARRANTY; without even the implied warranty of 12 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 | // GNU General Public License for more details. 14 | // 15 | // You should have received a copy of the GNU General Public License 16 | // along with aislib. If not, see . 17 | 18 | package aislib 19 | 20 | import "testing" 21 | 22 | func BenchmarkNmea183ChecksumCheck(b *testing.B) { 23 | for i := 0; i < b.N; i++ { 24 | Nmea183ChecksumCheck("!AIVDM,1,1,,B,38uP:WfuAO9PW. 17 | 18 | package aislib 19 | 20 | import ( 21 | "errors" 22 | "math" 23 | ) 24 | 25 | // A PositionReport is the generic structure of a Position Report, containing the common fields 26 | // between Class A and B reports. 27 | type PositionReport struct { 28 | Type uint8 29 | Repeat uint8 30 | MMSI uint32 31 | Speed float32 // speed over ground - SOG (sc U3) 32 | Accuracy bool // position accuracy 33 | Lon float64 // (sc I4) 34 | Lat float64 // (sc I4) 35 | Course float32 //course over ground - COG (sc U1) 36 | Heading uint16 // true heading - HDG 37 | Second uint8 // timestamp 38 | } 39 | 40 | // A ClassAPositionReport is a decoded AIS position message (messages of type 1, 2 or 3). 41 | // Please have a look at http://catb.org/gpsd/AIVDM.html and at 42 | // http://www.navcen.uscg.gov/?pageName=AISMessagesA 43 | type ClassAPositionReport struct { 44 | PositionReport 45 | RAIM bool // RAIM flag 46 | Radio uint32 // Radio status 47 | Status uint8 // navigation status (enumerated type) 48 | Turn float32 // rate of turn - ROT (sc - Special Calc I3) 49 | Maneuver uint8 // maneuver indicator (enumerated) 50 | } 51 | 52 | // A ClassBPositionReport is a decoded AIS position message (type 18). 53 | type ClassBPositionReport struct { 54 | PositionReport 55 | RAIM bool // RAIM flag 56 | Radio uint32 // Radio status 57 | CSUnit bool 58 | Display bool 59 | DSC bool 60 | Band bool 61 | Msg22 bool 62 | Assigned bool 63 | } 64 | 65 | // A ExtendedClassBPositionReport is a decoded AIS position message (type 19). 66 | type ExtendedClassBPositionReport struct { 67 | PositionReport 68 | VesselName string 69 | ShipType uint8 70 | ToBow uint16 // Dimension to bow 71 | ToStern uint16 // Dimension to stern 72 | ToPort uint8 // Dimension to port 73 | ToStarboard uint8 // Dimension to starboard 74 | EPFD uint8 // Position Fix Type (enumeration declared at basestationreport.go) 75 | RAIM bool // RAIM flag 76 | } 77 | 78 | // Navigation status codes 79 | var NavigationStatusCodes = [...]string{ 80 | "Under way using engine", "At anchor", "Not under command", "Restricted maneuverability", 81 | "Constrained by her draught", "Moored", "Aground", "Engaged in fishing", "Under way sailing", 82 | "status code reserved", "status code reserved", "status code reserved", 83 | "status code reserved", "status code reserved", "AIS-SART is active", "Not defined", 84 | } 85 | 86 | // DecodeClassAPositionReport decodes [the payload of] an AIS position message (type 1/2/3) 87 | func DecodeClassAPositionReport(payload string) (ClassAPositionReport, error) { 88 | data := []byte(payload) 89 | var m ClassAPositionReport 90 | 91 | m.Type = decodeAisChar(data[0]) 92 | if m.Type != 1 && m.Type != 2 && m.Type != 3 { 93 | return m, errors.New("Message isn't Class A Position Report (type 1, 2 or 3).") 94 | } 95 | 96 | // !!! This is the first decoding function written. Original decoding 97 | // routines are left here as comments, in order to help anyone diving 98 | // into binary field decoding. 99 | 100 | //m.Repeat = decodeAisChar(data[1]) >> 4 101 | m.Repeat = uint8(bitsToInt(6, 7, data)) 102 | 103 | //m.MMSI = uint32(decodeAisChar(data[1]))<<28>>2 | uint32(decodeAisChar(data[2]))<<20 | 104 | // uint32(decodeAisChar(data[3]))<<14 | uint32(decodeAisChar(data[4]))<<8 | 105 | // uint32(decodeAisChar(data[5]))<<2 | uint32(decodeAisChar(data[6]))>>4 106 | m.MMSI = bitsToInt(8, 37, data) 107 | 108 | //m.Status = (decodeAisChar(data[6]) << 4) >> 4 109 | m.Status = uint8(bitsToInt(38, 41, data)) 110 | 111 | //m.Turn = float32(int8(decodeAisChar(data[7])<<2 | decodeAisChar(data[8])>>4)) 112 | m.Turn = float32(int8(bitsToInt(42, 49, data))) 113 | if m.Turn != 0 && m.Turn <= 126 && m.Turn >= -126 { 114 | sign := float32(1) 115 | if math.Signbit(float64(m.Turn)) { 116 | sign = -1 117 | } 118 | m.Turn = sign * (m.Turn / 4.733) * (m.Turn / 4.733) 119 | 120 | } 121 | 122 | //m.Speed = float32(uint16(decodeAisChar(data[8]))<<12>>6 | uint16(decodeAisChar(data[9]))) 123 | m.Speed = cbnSpeed(50, data) 124 | 125 | //m.Accuracy = false 126 | //if decodeAisChar(data[10])>>5 == 1 { 127 | // m.Accuracy = true 128 | //} 129 | m.Accuracy = cbnBool(60, data) 130 | 131 | // Old method 1 132 | //m.Lon = float64((int32(decodeAisChar(data[10]))<<27 | int32(decodeAisChar(data[11]))<<21 | 133 | // int32(decodeAisChar(data[12]))<<15 | int32(decodeAisChar(data[13]))<<9 | 134 | // int32(decodeAisChar(data[14]))>>1<<4)) / 16 135 | //m.Lat = float64((int32(decodeAisChar(data[14]))<<31 | int32(decodeAisChar(data[15]))<<25 | 136 | // int32(decodeAisChar(data[16]))<<19 | int32(decodeAisChar(data[17]))<<13 | 137 | // int32(decodeAisChar(data[18]))<<7 | int32(decodeAisChar(data[19]))>>4<<5)) / 32 138 | // Old method 2 139 | //m.Lon = float64((int32(bitsToInt(61, 88, data)) << 4)) / 16 140 | //m.Lat = float64((int32(bitsToInt(89, 115, data)) << 5)) / 32 141 | // Finish or both old methods 142 | //m.Lon, m.Lat = CoordinatesMin2Deg(m.Lon, m.Lat) 143 | m.Lon, m.Lat = cbnCoordinates(61, data) 144 | 145 | //m.Course = float32(uint16(decodeAisChar(data[19]))<<12>>4|uint16(decodeAisChar(data[20]))<<2| 146 | // uint16(decodeAisChar(data[21]))>>4) / 10 147 | m.Course = float32(bitsToInt(116, 127, data)) / 10 148 | 149 | //m.Heading = uint16(decodeAisChar(data[21]))<<12>>7 | uint16(decodeAisChar(data[22]))>>1 150 | m.Heading = uint16(bitsToInt(128, 136, data)) 151 | 152 | //m.Second = decodeAisChar(data[22])<<7>>2 | decodeAisChar(data[23])>>1 153 | m.Second = uint8(bitsToInt(137, 142, data)) 154 | 155 | //m.Maneuver = decodeAisChar(data[23])<<7>>6 | decodeAisChar(data[24])>>5 156 | m.Maneuver = uint8(bitsToInt(143, 144, data)) 157 | 158 | //m.RAIM = false 159 | //if decodeAisChar(data[24])<<6>>7 == 1 { 160 | // m.RAIM = true 161 | //} 162 | m.RAIM = cbnBool(148, data) 163 | 164 | m.Radio = bitsToInt(149, 167, data) 165 | return m, nil 166 | } 167 | 168 | // DecodeClassBPositionReport decodes [the payload of] an AIS position message (type 18) 169 | func DecodeClassBPositionReport(payload string) (ClassBPositionReport, error) { 170 | data := []byte(payload) 171 | var m ClassBPositionReport 172 | 173 | m.Type = decodeAisChar(data[0]) 174 | if m.Type != 18 { 175 | return m, errors.New("Message isn't Class B Position Report (type 18).") 176 | } 177 | 178 | m.Repeat = uint8(bitsToInt(6, 7, data)) 179 | 180 | m.MMSI = bitsToInt(8, 37, data) 181 | 182 | m.Speed = cbnSpeed(46, data) 183 | 184 | m.Accuracy = cbnBool(56, data) 185 | 186 | m.Lon, m.Lat = cbnCoordinates(57, data) 187 | 188 | m.Course = float32(bitsToInt(112, 123, data)) / 10 189 | 190 | m.Heading = uint16(bitsToInt(124, 132, data)) 191 | 192 | m.Second = uint8(bitsToInt(133, 138, data)) 193 | 194 | m.CSUnit = cbnBool(141, data) 195 | m.Display = cbnBool(142, data) 196 | m.DSC = cbnBool(143, data) 197 | m.Band = cbnBool(144, data) 198 | m.Msg22 = cbnBool(145, data) 199 | m.Assigned = cbnBool(146, data) 200 | 201 | m.RAIM = cbnBool(147, data) 202 | if decodeAisChar(data[24])<<6>>7 == 1 { 203 | m.RAIM = true 204 | } 205 | 206 | m.Radio = bitsToInt(148, 167, data) 207 | return m, nil 208 | } 209 | 210 | // DecodeExtendedClassBPositionReport decodes [the payload of] an AIS extendedposition message (type 19) 211 | func DecodeExtendedClassBPositionReport(payload string) (ExtendedClassBPositionReport, error) { 212 | data := []byte(payload) 213 | var m ExtendedClassBPositionReport 214 | 215 | m.Type = decodeAisChar(data[0]) 216 | if m.Type != 19 { 217 | return m, errors.New("Message isn't Extended Class B Position Report (type 18).") 218 | } 219 | 220 | m.Repeat = uint8(bitsToInt(6, 7, data)) 221 | 222 | m.MMSI = bitsToInt(8, 37, data) 223 | 224 | m.Speed = cbnSpeed(46, data) 225 | 226 | m.Accuracy = cbnBool(56, data) 227 | 228 | m.Lon, m.Lat = cbnCoordinates(57, data) 229 | 230 | m.Course = float32(bitsToInt(112, 123, data)) / 10 231 | 232 | m.Heading = uint16(bitsToInt(124, 132, data)) 233 | 234 | m.Second = uint8(bitsToInt(133, 138, data)) 235 | 236 | m.VesselName = bitsToString(143, 262, data) 237 | 238 | m.ShipType = uint8(bitsToInt(263, 270, data)) 239 | 240 | m.ToBow = uint16(bitsToInt(271, 279, data)) 241 | m.ToStern = uint16(bitsToInt(280, 288, data)) 242 | m.ToPort = uint8(bitsToInt(289, 294, data)) 243 | m.ToStarboard = uint8(bitsToInt(295, 300, data)) 244 | 245 | m.EPFD = uint8(bitsToInt(301, 304, data)) 246 | m.RAIM = cbnBool(147, data) 247 | if decodeAisChar(data[24])<<6>>7 == 1 { 248 | m.RAIM = true 249 | } 250 | return m, nil 251 | } 252 | -------------------------------------------------------------------------------- /positionreport_test.go: -------------------------------------------------------------------------------- 1 | // Copyright (c) 2015, Marios Andreopoulos. 2 | // 3 | // This file is part of aislib. 4 | // 5 | // Aislib is free software: you can redistribute it and/or modify 6 | // it under the terms of the GNU General Public License as published by 7 | // the Free Software Foundation, either version 3 of the License, or 8 | // (at your option) any later version. 9 | // 10 | // Aislib is distributed in the hope that it will be useful, 11 | // but WITHOUT ANY WARRANTY; without even the implied warranty of 12 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 | // GNU General Public License for more details. 14 | // 15 | // You should have received a copy of the GNU General Public License 16 | // along with aislib. If not, see . 17 | 18 | package aislib 19 | 20 | import ( 21 | "fmt" 22 | "testing" 23 | ) 24 | 25 | // We don't decode radio field, so testing on radio field isn't really verified. 26 | // Radio is a 19bit field which we decode as uint32. One would need to decode further 27 | // these 19 bits but its uneccesary for now. 28 | func TestDecodeClassAPositionReport(t *testing.T) { 29 | cases := []struct { 30 | payload string 31 | want ClassAPositionReport 32 | }{ 33 | { 34 | "38uP:WfuAO9PWL089D", 44 | ClassAPositionReport{ 45 | PositionReport: PositionReport{ 46 | Type: 1, Repeat: 0, MMSI: 235060799, Speed: 0.9, 47 | Accuracy: false, Lon: -3.56725, Lat: 53.84251666666667, Course: 123, 48 | Heading: 167, Second: 14, RAIM: false, Radio: 33364}, 49 | Status: 0, Turn: 0, Maneuver: 0}, 50 | }, 51 | { 52 | "13n@oD0PB@0IRqvQj@W;EppH088t19uvPT", 53 | ClassAPositionReport{ 54 | PositionReport: PositionReport{ 55 | Type: 1, Repeat: 0, MMSI: 258226000, Speed: 14.4, 56 | Accuracy: false, Lon: 5.580478333333334, Lat: 59.0441, Course: 290.3, 57 | Heading: 284, Second: 12, RAIM: false, Radio: 33340}, 58 | Status: 0, Turn: -127, Maneuver: 0}, 59 | }, 60 | } 61 | for _, c := range cases { 62 | got, _ := DecodeClassAPositionReport(c.payload) 63 | if got != c.want { 64 | fmt.Println("Got : ", got) 65 | fmt.Println("Want: ", c.want) 66 | t.Errorf("DecodeClassAPositionReport(payload string)") 67 | } 68 | } 69 | } 70 | 71 | func BenchmarkDecodeClassAPositionReport(b *testing.B) { 72 | for i := 0; i < b.N; i++ { 73 | DecodeClassAPositionReport("38uP:WfuAO9PW. 17 | 18 | package aislib 19 | 20 | import ( 21 | "fmt" 22 | "strconv" 23 | ) 24 | 25 | // PrintBaseStationReport returns a formatted string of a BaseStationReport. Mainly to help 26 | // developers with understanding base position reports. 27 | func (m BaseStationReport) String() string { 28 | accuracy := "High accuracy (<10m)" 29 | if m.Accuracy == false { 30 | accuracy = "Low accuracy (>10m)" 31 | } 32 | 33 | raim := "not in use" 34 | if m.RAIM == true { 35 | raim = "in use" 36 | } 37 | 38 | message := 39 | fmt.Sprintf("=== Base Station Report ===\n") + 40 | fmt.Sprintf(" Repeat : %d\n", m.Repeat) + 41 | fmt.Sprintf(" MMSI : %09d [%s]\n", m.MMSI, DecodeMMSI(m.MMSI)) + 42 | fmt.Sprintf(" Time : %s\n", m.Time.String()) + 43 | fmt.Sprintf(" Accuracy : %s\n", accuracy) + 44 | fmt.Sprintf(" Coordinates : %s\n", CoordinatesDeg2Human(m.Lon, m.Lat)) + 45 | fmt.Sprintf(" EPFD : %s\n", EpfdFixTypes[m.EPFD]) + 46 | fmt.Sprintf(" RAIM : %s\n", raim) 47 | 48 | return message 49 | } 50 | 51 | // PrintClassAPositionReport returns a formatted string with the detailed data of a AIS position message. 52 | // Its main use is to act as a guide for any developer wishing to correctly parse an AIS position message, 53 | // since some parts of a message are enumareted, and other parts although they mainly are numeric values, 54 | // for certain values they can have a non-numeric meaning. 55 | func (m ClassAPositionReport) String() string { 56 | turn := "" 57 | switch { 58 | case m.Turn == 0: 59 | turn = "not turning" 60 | case m.Turn == 127: 61 | turn = "right at more than 5deg/30s" 62 | case m.Turn == -127: 63 | turn = "left at more than 5deg/30s" 64 | case m.Turn == -128: 65 | turn = "no turn information" 66 | case m.Turn > 0 && m.Turn < 127: 67 | turn = "right at " + strconv.FormatFloat(float64(m.Turn), 'f', 3, 32) 68 | case m.Turn < 0 && m.Turn > -127: 69 | turn = "left at " + strconv.FormatFloat(float64(-m.Turn), 'f', 3, 32) 70 | } 71 | 72 | speed := "" 73 | switch { 74 | case m.Speed <= 102: 75 | speed = strconv.FormatFloat(float64(m.Speed), 'f', 1, 32) + " knots" 76 | case m.Speed == 1022: 77 | speed = ">102.2 knots" 78 | case m.Speed == 1023: 79 | speed = "information not available" 80 | } 81 | 82 | accuracy := "High accuracy (<10m)" 83 | if m.Accuracy == false { 84 | accuracy = "Low accuracy (>10m)" 85 | } 86 | 87 | course := "" 88 | switch { 89 | case m.Course < 360: 90 | course = fmt.Sprintf("%.1f°", m.Course) 91 | case m.Course == 360: 92 | course = "not available" 93 | case m.Course > 360: 94 | course = "please report this to developer" 95 | } 96 | 97 | heading := "" 98 | switch { 99 | case m.Heading <= 359: 100 | heading = fmt.Sprintf("%d°", m.Heading) 101 | case m.Heading == 511: 102 | heading = "not available" 103 | case m.Heading != 511 && m.Heading >= 360: 104 | heading = "please report this to developer" 105 | } 106 | 107 | maneuver := "" 108 | switch { 109 | case m.Maneuver == 0: 110 | maneuver = "not available" 111 | case m.Maneuver == 1: 112 | maneuver = "no special maneuver" 113 | case m.Maneuver == 2: 114 | maneuver = "special maneuver" 115 | } 116 | 117 | raim := "not in use" 118 | if m.RAIM == true { 119 | raim = "in use" 120 | } 121 | 122 | message := 123 | fmt.Sprintf("=== Class A Position Report (%d) ===\n", m.Type) + 124 | fmt.Sprintf(" Repeat : %d\n", m.Repeat) + 125 | fmt.Sprintf(" MMSI : %09d [%s]\n", m.MMSI, DecodeMMSI(m.MMSI)) + 126 | fmt.Sprintf(" Nav.Status : %s\n", NavigationStatusCodes[m.Status]) + 127 | fmt.Sprintf(" Turn (ROT) : %s\n", turn) + 128 | fmt.Sprintf(" Speed (SOG) : %s\n", speed) + 129 | fmt.Sprintf(" Accuracy : %s\n", accuracy) + 130 | fmt.Sprintf(" Coordinates : %s\n", CoordinatesDeg2Human(m.Lon, m.Lat)) + 131 | fmt.Sprintf(" Course (COG) : %s\n", course) + 132 | fmt.Sprintf(" Heading (HDG): %s\n", heading) + 133 | fmt.Sprintf(" Manuever ind.: %s\n", maneuver) + 134 | fmt.Sprintf(" RAIM : %s\n", raim) 135 | 136 | return message 137 | } 138 | 139 | // PrintClassBPositionReport returns a formatted string with the detailed data of a AIS position message. 140 | // Its main use is to act as a guide for any developer wishing to correctly parse an AIS position message, 141 | // since some parts of a message are enumareted, and other parts although they mainly are numeric values, 142 | // for certain values they can have a non-numeric meaning. 143 | func (m ClassBPositionReport) String() string { 144 | speed := "" 145 | switch { 146 | case m.Speed <= 102: 147 | speed = strconv.FormatFloat(float64(m.Speed), 'f', 1, 32) + " knots" 148 | case m.Speed == 1022: 149 | speed = ">102.2 knots" 150 | case m.Speed == 1023: 151 | speed = "information not available" 152 | } 153 | 154 | accuracy := "High accuracy (<10m)" 155 | if m.Accuracy == false { 156 | accuracy = "Low accuracy (>10m)" 157 | } 158 | 159 | course := "" 160 | switch { 161 | case m.Course < 360: 162 | course = fmt.Sprintf("%.1f°", m.Course) 163 | case m.Course == 360: 164 | course = "not available" 165 | case m.Course > 360: 166 | course = "please report this to developer" 167 | } 168 | 169 | heading := "" 170 | switch { 171 | case m.Heading <= 359: 172 | heading = fmt.Sprintf("%d°", m.Heading) 173 | case m.Heading == 511: 174 | heading = "not available" 175 | case m.Heading != 511 && m.Heading >= 360: 176 | heading = "please report this to developer" 177 | } 178 | 179 | message := 180 | fmt.Sprintf("=== Class B Position Report ===\n") + 181 | fmt.Sprintf(" Repeat : %d\n", m.Repeat) + 182 | fmt.Sprintf(" MMSI : %09d [%s]\n", m.MMSI, DecodeMMSI(m.MMSI)) + 183 | fmt.Sprintf(" Speed (SOG) : %s\n", speed) + 184 | fmt.Sprintf(" Accuracy : %s\n", accuracy) + 185 | fmt.Sprintf(" Coordinates : %s\n", CoordinatesDeg2Human(m.Lon, m.Lat)) + 186 | fmt.Sprintf(" Course (COG) : %s\n", course) + 187 | fmt.Sprintf(" Heading (HDG): %s\n", heading) + 188 | fmt.Sprintf(" CS Unit : %t\n", m.CSUnit) + 189 | fmt.Sprintf(" Display : %t\n", m.Display) + 190 | fmt.Sprintf(" DSC : %t\n", m.DSC) + 191 | fmt.Sprintf(" Band : %t\n", m.Band) + 192 | fmt.Sprintf(" Message 22 : %t\n", m.Msg22) + 193 | fmt.Sprintf(" Assigned : %t\n", m.Assigned) + 194 | fmt.Sprintf(" RAIM : %t\n", m.RAIM) 195 | 196 | return message 197 | } 198 | 199 | // PrintStaticVoyageData returns a formatted string with the detailed data of a AIS Static and Voyage 200 | // Related Data (message type 5). Its main use is to act as a guide for any developer wishing to 201 | // correctly parse an AIS type 5 message since some parts are enumareted, and other parts although 202 | // they mainly are numeric values, for certain values they can have a non-numeric meaning. 203 | func (m StaticVoyageData) String() string { 204 | 205 | imo := "" 206 | if m.IMO == 0 { 207 | imo = "Inland Vessel" 208 | } else { 209 | imo = strconv.Itoa(int(m.IMO)) 210 | } 211 | 212 | draught := "" 213 | if m.Draught == 0 { 214 | draught = "Not available" 215 | } else { 216 | draught = strconv.Itoa(10*int(m.IMO)) + " meters" 217 | } 218 | 219 | message := 220 | fmt.Sprintf("=== Static and Voyage Related Data ===\n") + 221 | fmt.Sprintf(" Repeat : %d\n", m.Repeat) + 222 | fmt.Sprintf(" MMSI : %09d [%s]\n", m.MMSI, DecodeMMSI(m.MMSI)) + 223 | fmt.Sprintf(" AIS Version : %d\n", m.AisVersion) + 224 | fmt.Sprintf(" IMO number : %s\n", imo) + 225 | fmt.Sprintf(" Call Sign : %s\n", m.Callsign) + 226 | fmt.Sprintf(" Vessel Name : %s\n", m.VesselName) + 227 | fmt.Sprintf(" Ship Type : %s\n", ShipType[int(m.ShipType)]) + 228 | fmt.Sprintf(" Dim to Bow : %s\n", type5size2String(0, 511, int(m.ToBow))) + 229 | fmt.Sprintf(" Dim to Stern : %s\n", type5size2String(0, 511, int(m.ToStern))) + 230 | fmt.Sprintf(" Dim to Port : %s\n", type5size2String(0, 511, int(m.ToPort))) + 231 | fmt.Sprintf(" Dim to StrBrd: %s\n", type5size2String(0, 511, int(m.ToStarboard))) + 232 | fmt.Sprintf(" EPFD : %s\n", EpfdFixTypes[m.EPFD]) + 233 | fmt.Sprintf(" ETA : %s\n", m.ETA.String()) + 234 | fmt.Sprintf(" Draught : %s\n", draught) + 235 | fmt.Sprintf(" Destination : %s\n", m.Destination) 236 | 237 | return message 238 | } 239 | 240 | // A small function to translate the size fields 241 | func type5size2String(min, max, size int) string { 242 | s := "" 243 | switch size { 244 | case min: 245 | s = "Not available" 246 | case max: 247 | s = ">" + strconv.Itoa(max) + " meters" 248 | default: 249 | s = strconv.Itoa(size) + " meters" 250 | } 251 | return s 252 | } 253 | 254 | // PrintBinaryBroadcast returns a string with some data for a Binary Broadcast message 255 | func (m BinaryBroadcast) String() string { 256 | 257 | message := 258 | fmt.Sprintf("=== Binary Broadcast ===\n") + 259 | fmt.Sprintf(" Repeat : %d\n", m.Repeat) + 260 | fmt.Sprintf(" MMSI : %09d [%s]\n", m.MMSI, DecodeMMSI(m.MMSI)) + 261 | fmt.Sprintf(" DAC-FID : %d-%d (%s)\n", m.DAC, m.FID, BinaryBroadcastType[int(m.DAC)][int(m.FID)]) 262 | 263 | return message 264 | } 265 | -------------------------------------------------------------------------------- /router.go: -------------------------------------------------------------------------------- 1 | // Copyright (c) 2015, Marios Andreopoulos. 2 | // 3 | // This file is part of aislib. 4 | // 5 | // Aislib is free software: you can redistribute it and/or modify 6 | // it under the terms of the GNU General Public License as published by 7 | // the Free Software Foundation, either version 3 of the License, or 8 | // (at your option) any later version. 9 | // 10 | // Aislib is distributed in the hope that it will be useful, 11 | // but WITHOUT ANY WARRANTY; without even the implied warranty of 12 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 | // GNU General Public License for more details. 14 | // 15 | // You should have received a copy of the GNU General Public License 16 | // along with aislib. If not, see . 17 | 18 | package aislib 19 | 20 | import ( 21 | "strconv" 22 | "strings" 23 | ) 24 | 25 | // A Message stores the important properties of a AIS message, including only information useful 26 | // for decoding: Type, Payload, Padding Bits 27 | // A Message should come after processing one or more AIS radio sentences (checksum check, 28 | // concatenate payloads spanning across sentences, etc). 29 | type Message struct { 30 | Type uint8 31 | Payload string 32 | Padding uint8 33 | } 34 | 35 | // FailedSentence includes an AIS sentence that failed to process (e.g wrong checksum) and the reason 36 | // it failed. 37 | type FailedSentence struct { 38 | Sentence string 39 | Issue string 40 | } 41 | 42 | // Router accepts AIS radio sentences and process them. It checks their checksum, 43 | // and AIS identifiers. If they are valid it tries to assemble the payload if it spans 44 | // on multiple sentences. Upon success it returns the AIS Message at the out channel. 45 | // Failed sentences go to the err channel. 46 | // If the in channel is closed, then it sends a message with type 255 at the out channel. 47 | // Your function can check for this message to know when it is safe to exit the program. 48 | func Router(in chan string, out chan Message, failed chan FailedSentence) { 49 | count, ccount, padding := 0, 0, 0 50 | size, id := "0", "0" 51 | payload := "" 52 | var cache [5]string 53 | var err error 54 | aisIdentifiers := map[string]bool{ 55 | "ABVD": true, "ADVD": true, "AIVD": true, "ANVD": true, "ARVD": true, 56 | "ASVD": true, "ATVD": true, "AXVD": true, "BSVD": true, "SAVD": true, 57 | } 58 | for sentence := range in { 59 | if len(sentence) == 0 { // Do not process empty lines 60 | failed <- FailedSentence{sentence, "Empty line"} 61 | continue 62 | } 63 | tokens := strings.Split(sentence, ",") // I think this takes the major portion of time for this function (after benchmarking) 64 | 65 | if !Nmea183ChecksumCheck(sentence) { // Checksum check 66 | failed <- FailedSentence{sentence, "Checksum failed"} 67 | continue 68 | } 69 | 70 | if !aisIdentifiers[tokens[0][1:5]] { // Check for valid AIS identifier 71 | failed <- FailedSentence{sentence, "Sentence isn't AIVDM/AIVDO"} 72 | continue 73 | } 74 | 75 | if tokens[1] == "1" { // One sentence message, process it immediately 76 | padding, _ = strconv.Atoi(tokens[6][:1]) 77 | out <- Message{MessageType(tokens[5]), tokens[5], uint8(padding)} 78 | if count > 1 { // Invalidate cache 79 | for i := 0; i < count; i++ { 80 | failed <- FailedSentence{cache[i], "Incomplete/out of order span sentence"} 81 | } 82 | count = 0 83 | payload = "" 84 | } 85 | } else { // Message spans across sentences. 86 | ccount, err = strconv.Atoi(tokens[2]) 87 | if err != nil { 88 | failed <- FailedSentence{sentence, "HERE " + tokens[2]} 89 | continue 90 | } 91 | if ccount != count+1 || // If there are sentences with wrong seq.number in cache send them as failed 92 | tokens[3] != id && count != 0 || // If there are sentences with different sequence id in cache , send old parts as failed 93 | tokens[1] != size && count != 0 { // If there messages with wrong size in cache, send them as failed 94 | for i := 0; i < count; i++ { 95 | failed <- FailedSentence{cache[i], "Incomplete/out of order span sentence"} 96 | } 97 | if ccount != 1 { // The current one is invalid too 98 | failed <- FailedSentence{sentence, "Incomplete/out of order span sentence"} 99 | count = 0 100 | payload = "" 101 | continue 102 | } 103 | count = 0 104 | payload = "" 105 | } 106 | payload += tokens[5] 107 | cache[ccount-1] = sentence 108 | count++ 109 | if ccount == 1 { // First message in sequence, get size and id 110 | size = tokens[1] 111 | id = tokens[3] 112 | } else if size == tokens[2] && count == ccount { // Last message in sequence, send it and clean up. 113 | padding, _ = strconv.Atoi(tokens[6][:1]) 114 | out <- Message{MessageType(payload), payload, uint8(padding)} 115 | count = 0 116 | payload = "" 117 | } 118 | } 119 | } 120 | out <- Message{255, "", 0} 121 | } 122 | -------------------------------------------------------------------------------- /router_test.go: -------------------------------------------------------------------------------- 1 | // Copyright (c) 2015, Marios Andreopoulos. 2 | // 3 | // This file is part of aislib. 4 | // 5 | // Aislib is free software: you can redistribute it and/or modify 6 | // it under the terms of the GNU General Public License as published by 7 | // the Free Software Foundation, either version 3 of the License, or 8 | // (at your option) any later version. 9 | // 10 | // Aislib is distributed in the hope that it will be useful, 11 | // but WITHOUT ANY WARRANTY; without even the implied warranty of 12 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 | // GNU General Public License for more details. 14 | // 15 | // You should have received a copy of the GNU General Public License 16 | // along with aislib. If not, see . 17 | 18 | package aislib 19 | 20 | import ( 21 | "fmt" 22 | "testing" 23 | ) 24 | 25 | func TestRouter(t *testing.T) { 26 | cases := []struct { 27 | message Message 28 | sentence []string 29 | }{ 30 | { 31 | Message{3, "38uP:WfuAO9PWP:WfuAO9PWNl0oKaCLIdeFlrc0", 2}, 41 | []string{"!AIVDM,3,1,7,A,85Mwom1KfI?GRNl0oKaCLIdeFlrc0,2*08"}, 44 | }, 45 | } 46 | 47 | send := make(chan string) 48 | receive := make(chan Message, 1024) 49 | failed := make(chan FailedSentence, 1024) 50 | 51 | go Router(send, receive, failed) 52 | 53 | for _, c := range cases { 54 | for _, m := range c.sentence { 55 | send <- m 56 | } 57 | got := <-receive 58 | if got != c.message { 59 | fmt.Println("Got : ", got) 60 | fmt.Println("Want: ", c.message) 61 | t.Errorf("Router(in chan string, out chan Message, failed chan FailedSentence)") 62 | } 63 | } 64 | } 65 | 66 | func BenchmarkRouter(b *testing.B) { 67 | send := make(chan string) 68 | receive := make(chan Message, 1024) 69 | failed := make(chan FailedSentence, 1024) 70 | 71 | go Router(send, receive, failed) 72 | 73 | for i := 0; i < b.N; i++ { 74 | if i%2 == 0 { 75 | send <- "!AIVDM,1,1,,B,38uP:WfuAO9PWP:WfuAO9PW. 17 | 18 | package aislib 19 | 20 | import ( 21 | "errors" 22 | ) 23 | 24 | // A StaticDataReport is a decoded AIS static data report (message type 24) 25 | type StaticDataReport struct { 26 | Repeat uint8 27 | MMSI uint32 28 | PartNo uint8 29 | //PartA 30 | VesselName string 31 | //PartB 32 | ShipType uint8 33 | VendorID string 34 | UnitModelCode uint8 35 | SerialNumber uint32 36 | CallSign string 37 | // optional with MothershipMMSI 38 | ToBow uint16 // Dimension to bow 39 | ToStern uint16 // Dimension to stern 40 | ToPort uint8 // Dimension to port 41 | ToStarboard uint8 // Dimension to starboard 42 | MothershipMMSI uint32 43 | } 44 | 45 | // DecodeStaticDataReport decodes the payload of a Type 24 AIS message 46 | func DecodeStaticDataReport(payload string) (StaticDataReport, error) { 47 | data := []byte(payload) 48 | var m StaticDataReport 49 | 50 | mType := decodeAisChar(data[0]) 51 | if mType != 24 { 52 | return m, errors.New("Message isn't Static Data Station Report (type 24).") 53 | } 54 | 55 | m.Repeat = uint8(bitsToInt(6, 7, data)) 56 | 57 | //m.MMSI = uint32(decodeAisChar(data[1]))<<28>>2 | uint32(decodeAisChar(data[2]))<<20 | 58 | // uint32(decodeAisChar(data[3]))<<14 | uint32(decodeAisChar(data[4]))<<8 | 59 | // uint32(decodeAisChar(data[5]))<<2 | uint32(decodeAisChar(data[6]))>>4 60 | m.MMSI = bitsToInt(8, 37, data) 61 | 62 | m.PartNo = uint8(bitsToInt(38, 39, data)) 63 | if m.PartNo == 0 { 64 | m.VesselName = bitsToString(112, 231, data) 65 | } else { 66 | m.ShipType = uint8(bitsToInt(40, 47, data)) 67 | m.VendorID = bitsToString(48, 65, data) 68 | 69 | m.UnitModelCode = uint8(bitsToInt(66, 69, data)) 70 | m.SerialNumber = uint32(bitsToInt(70, 89, data)) 71 | m.CallSign = bitsToString(90, 131, data) 72 | 73 | // its an auxiliary craft 74 | if m.MMSI >= 980000000 { 75 | m.MothershipMMSI = bitsToInt(132, 161, data) 76 | } else { 77 | m.ToBow = uint16(bitsToInt(132, 140, data)) 78 | m.ToStern = uint16(bitsToInt(141, 149, data)) 79 | m.ToPort = uint8(bitsToInt(150, 155, data)) 80 | m.ToStarboard = uint8(bitsToInt(156, 161, data)) 81 | } 82 | } 83 | 84 | return m, nil 85 | } 86 | -------------------------------------------------------------------------------- /staticvoyagedata.go: -------------------------------------------------------------------------------- 1 | // Copyright (c) 2015, Marios Andreopoulos. 2 | // 3 | // This file is part of aislib. 4 | // 5 | // Aislib is free software: you can redistribute it and/or modify 6 | // it under the terms of the GNU General Public License as published by 7 | // the Free Software Foundation, either version 3 of the License, or 8 | // (at your option) any later version. 9 | // 10 | // Aislib is distributed in the hope that it will be useful, 11 | // but WITHOUT ANY WARRANTY; without even the implied warranty of 12 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 | // GNU General Public License for more details. 14 | // 15 | // You should have received a copy of the GNU General Public License 16 | // along with aislib. If not, see . 17 | 18 | package aislib 19 | 20 | import ( 21 | "errors" 22 | "fmt" 23 | "time" 24 | ) 25 | 26 | // StaticVoyageData is a type 5 AIS message (static and voyage related data) 27 | // ETA is not reliable 28 | type StaticVoyageData struct { 29 | Repeat uint8 30 | MMSI uint32 31 | AisVersion uint8 32 | IMO uint32 // IMO Ship ID number 33 | Callsign string 34 | VesselName string 35 | ShipType uint8 36 | ToBow uint16 // Dimension to bow 37 | ToStern uint16 // Dimension to stern 38 | ToPort uint8 // Dimension to port 39 | ToStarboard uint8 // Dimension to starboard 40 | EPFD uint8 // Position Fix Type (enumeration declared at basestationreport.go) 41 | ETA time.Time // Not reliable 42 | Draught uint8 // Meters/10 43 | Destination string 44 | DTE bool 45 | } 46 | 47 | // DecodeStaticVoyageData decodes [the payload of] an AIS Static and Voyage Related Data message (type 5) 48 | func DecodeStaticVoyageData(payload string) (StaticVoyageData, error) { 49 | data := []byte(payload) 50 | var m StaticVoyageData 51 | 52 | mType := decodeAisChar(data[0]) 53 | if mType != 5 { 54 | return m, errors.New("Message isn't Static and Voyage Related Data (type 5).") 55 | } 56 | m.Repeat = uint8(bitsToInt(6, 7, data)) 57 | 58 | m.MMSI = uint32(bitsToInt(8, 37, data)) 59 | 60 | m.AisVersion = uint8(bitsToInt(38, 39, data)) 61 | 62 | m.IMO = uint32(bitsToInt(40, 69, data)) 63 | 64 | m.Callsign = bitsToString(70, 111, data) 65 | 66 | m.VesselName = bitsToString(112, 231, data) 67 | 68 | m.ShipType = uint8(bitsToInt(232, 239, data)) 69 | 70 | m.ToBow = uint16(bitsToInt(240, 248, data)) 71 | m.ToStern = uint16(bitsToInt(249, 257, data)) 72 | m.ToPort = uint8(bitsToInt(258, 263, data)) 73 | m.ToStarboard = uint8(bitsToInt(264, 269, data)) 74 | 75 | m.EPFD = uint8(bitsToInt(270, 273, data)) 76 | 77 | // ETA does not include year, so we omit it too (it is set as 0000) 78 | // cyear := time.Now().Year() 79 | month := uint8(bitsToInt(274, 277, data)) 80 | day := uint8(bitsToInt(278, 282, data)) 81 | hour := uint8(bitsToInt(283, 287, data)) 82 | minute := uint8(bitsToInt(288, 293, data)) 83 | timeString := fmt.Sprintf("%d/%d %d:%d", month, day, hour, minute) 84 | m.ETA, _ = time.Parse("1/2 15:4", timeString) 85 | 86 | m.Draught = uint8(bitsToInt(294, 301, data)) 87 | 88 | m.Destination = bitsToString(302, 421, data) 89 | 90 | m.DTE = cbnBool(422, data) 91 | 92 | return m, nil 93 | } 94 | 95 | // Ship types codes. 96 | var ShipType = map[int]string{ 97 | 0: "Not available", 98 | 1: "Reserved for future use", 99 | 2: "Reserved for future use", 100 | 3: "Reserved for future use", 101 | 4: "Reserved for future use", 102 | 5: "Reserved for future use", 103 | 6: "Reserved for future use", 104 | 7: "Reserved for future use", 105 | 8: "Reserved for future use", 106 | 9: "Reserved for future use", 107 | 10: "Reserved for future use", 108 | 11: "Reserved for future use", 109 | 12: "Reserved for future use", 110 | 13: "Reserved for future use", 111 | 14: "Reserved for future use", 112 | 15: "Reserved for future use", 113 | 16: "Reserved for future use", 114 | 17: "Reserved for future use", 115 | 18: "Reserved for future use", 116 | 19: "Reserved for future use", 117 | 20: "Wing in ground (WIG)", 118 | 21: "Wing in ground (WIG), Hazardous category A", 119 | 22: "Wing in ground (WIG), Hazardous category B", 120 | 23: "Wing in ground (WIG), Hazardous category C", 121 | 24: "Wing in ground (WIG), Hazardous category D", 122 | 25: "Wing in ground (WIG), Reserved for future use", 123 | 26: "Wing in ground (WIG), Reserved for future use", 124 | 27: "Wing in ground (WIG), Reserved for future use", 125 | 28: "Wing in ground (WIG), Reserved for future use", 126 | 29: "Wing in ground (WIG), Reserved for future use", 127 | 30: "Fishing", 128 | 31: "Towing", 129 | 32: "Towing: length exceeds 200m or breadth exceeds 25m", 130 | 33: "Dredging or underwater ops", 131 | 34: "Diving ops", 132 | 35: "Military ops", 133 | 36: "Sailing", 134 | 37: "Pleasure Craft", 135 | 38: "Reserved", 136 | 39: "Reserved", 137 | 40: "High speed craft (HSC)", 138 | 41: "High speed craft (HSC), Hazardous category A", 139 | 42: "High speed craft (HSC), Hazardous category B", 140 | 43: "High speed craft (HSC), Hazardous category C", 141 | 44: "High speed craft (HSC), Hazardous category D", 142 | 45: "High speed craft (HSC), Reserved for future use", 143 | 46: "High speed craft (HSC), Reserved for future use", 144 | 47: "High speed craft (HSC), Reserved for future use", 145 | 48: "High speed craft (HSC), Reserved for future use", 146 | 49: "High speed craft (HSC), No additional information", 147 | 50: "Pilot Vessel", 148 | 51: "Search and Rescue vessel", 149 | 52: "Tug", 150 | 53: "Port Tender", 151 | 54: "Anti-pollution equipment", 152 | 55: "Law Enforcement", 153 | 56: "Spare - Local Vessel", 154 | 57: "Spare - Local Vessel", 155 | 58: "Medical Transport", 156 | 59: "Noncombatant ship according to RR Resolution No. 18", 157 | 60: "Passenger", 158 | 61: "Passenger, Hazardous category A", 159 | 62: "Passenger, Hazardous category B", 160 | 63: "Passenger, Hazardous category C", 161 | 64: "Passenger, Hazardous category D", 162 | 65: "Passenger, Reserved for future use", 163 | 66: "Passenger, Reserved for future use", 164 | 67: "Passenger, Reserved for future use", 165 | 68: "Passenger, Reserved for future use", 166 | 69: "Passenger, No additional information", 167 | 70: "Cargo", 168 | 71: "Cargo, Hazardous category A", 169 | 72: "Cargo, Hazardous category B", 170 | 73: "Cargo, Hazardous category C", 171 | 74: "Cargo, Hazardous category D", 172 | 75: "Cargo, Reserved for future use", 173 | 76: "Cargo, Reserved for future use", 174 | 77: "Cargo, Reserved for future use", 175 | 78: "Cargo, Reserved for future use", 176 | 79: "Cargo, No additional information", 177 | 80: "Tanker", 178 | 81: "Tanker, Hazardous category A", 179 | 82: "Tanker, Hazardous category B", 180 | 83: "Tanker, Hazardous category C", 181 | 84: "Tanker, Hazardous category D", 182 | 85: "Tanker, Reserved for future use", 183 | 86: "Tanker, Reserved for future use", 184 | 87: "Tanker, Reserved for future use", 185 | 88: "Tanker, Reserved for future use", 186 | 89: "Tanker, No additional information", 187 | 90: "Other Type", 188 | 91: "Other Type, Hazardous category A", 189 | 92: "Other Type, Hazardous category B", 190 | 93: "Other Type, Hazardous category C", 191 | 94: "Other Type, Hazardous category D", 192 | 95: "Other Type, Reserved for future use", 193 | 96: "Other Type, Reserved for future use", 194 | 97: "Other Type, Reserved for future use", 195 | 98: "Other Type, Reserved for future use", 196 | 99: "Other Type, no additional information", 197 | } 198 | -------------------------------------------------------------------------------- /staticvoyagedata_test.go: -------------------------------------------------------------------------------- 1 | // Copyright (c) 2015, Marios Andreopoulos. 2 | // 3 | // This file is part of aislib. 4 | // 5 | // Aislib is free software: you can redistribute it and/or modify 6 | // it under the terms of the GNU General Public License as published by 7 | // the Free Software Foundation, either version 3 of the License, or 8 | // (at your option) any later version. 9 | // 10 | // Aislib is distributed in the hope that it will be useful, 11 | // but WITHOUT ANY WARRANTY; without even the implied warranty of 12 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 | // GNU General Public License for more details. 14 | // 15 | // You should have received a copy of the GNU General Public License 16 | // along with aislib. If not, see . 17 | 18 | package aislib 19 | 20 | import ( 21 | "fmt" 22 | "testing" 23 | "time" 24 | ) 25 | 26 | func TestDecodeStaticVoyageData(t *testing.T) { 27 | caseTime1, _ := time.Parse("1/2 15:4", "3/11 21:15") 28 | caseTime2, _ := time.Parse("1/2 15:4", "0/0 0:0") 29 | cases := []struct { 30 | payload string 31 | want StaticVoyageData 32 | }{ 33 | { 34 | "53uJur01rN?U<9@T001@tI@F000000000000000l0pA444mm?:1km1@SlQp000000000000", 35 | StaticVoyageData{ 36 | Repeat: 0, MMSI: 265731560, AisVersion: 0, IMO: 8026361, Callsign: "SBTI", 37 | VesselName: "TOFTE", ShipType: 52, ToBow: 7, ToStern: 17, ToPort: 4, ToStarboard: 4, 38 | EPFD: 1, ETA: caseTime1, Draught: 40, Destination: "GOTEBORG", DTE: false, 39 | }, 40 | }, 41 | { 42 | "53m`0o400000hKGCON18E<=DF0:1", 43 | StaticVoyageData{ 44 | Repeat: 0, MMSI: 257556700, AisVersion: 1, IMO: 0, Callsign: "LF5477", 45 | VesselName: "RESCUE B", ShipType: 0, ToBow: 0, ToStern: 0, ToPort: 0, ToStarboard: 0, 46 | EPFD: 0, ETA: caseTime2, Draught: 0, Destination: "", DTE: false, 47 | }, 48 | }, 49 | } 50 | for _, c := range cases { 51 | got, _ := DecodeStaticVoyageData(c.payload) 52 | if got != c.want { 53 | fmt.Println("Got : ", got) 54 | fmt.Println("Want: ", c.want) 55 | t.Errorf("DecodeStaticVoyageData(payload string)") 56 | } 57 | } 58 | } 59 | 60 | func BenchmarkDecodeStaticVoyageData(b *testing.B) { 61 | for i := 0; i < b.N; i++ { 62 | DecodeStaticVoyageData("53uJur01rN?U<9@T001@tI@F000000000000000l0pA444mm?:1km1@SlQp000000000000") 63 | } 64 | } 65 | --------------------------------------------------------------------------------