├── .github └── ISSUE_TEMPLATE │ └── bug_report.md ├── LICENSE └── README.md /.github/ISSUE_TEMPLATE/bug_report.md: -------------------------------------------------------------------------------- 1 | --- 2 | name: Bug report 3 | about: Create a report to help us improve 4 | title: '' 5 | labels: '' 6 | assignees: '' 7 | 8 | --- 9 | 10 | **Describe the bug** 11 | A clear and concise description of what the bug is. 12 | 13 | **To Reproduce** 14 | Steps to reproduce the behavior: 15 | 1. Go to '...' 16 | 2. Click on '....' 17 | 3. Scroll down to '....' 18 | 4. See error 19 | 20 | **Expected behavior** 21 | A clear and concise description of what you expected to happen. 22 | 23 | **Screenshots** 24 | If applicable, add screenshots to help explain your problem. 25 | 26 | **Desktop (please complete the following information):** 27 | - OS: [e.g. iOS] 28 | - Browser [e.g. chrome, safari] 29 | - Version [e.g. 22] 30 | 31 | **Smartphone (please complete the following information):** 32 | - Device: [e.g. iPhone6] 33 | - OS: [e.g. iOS8.1] 34 | - Browser [e.g. stock browser, safari] 35 | - Version [e.g. 22] 36 | 37 | **Additional context** 38 | Add any other context about the problem here. 39 | -------------------------------------------------------------------------------- /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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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 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | 2 | # UDP multicast 3 | 4 | #### UDP multicast MPEG-TS streams on Linux 5 | 6 | > A most common task for all OTT and IPTV video services is, of course, to encode a group of TV channels. And the most common way you will be receiving channels is MPEG-TS streams via multicast UDP. In this article we have explained some popular tips and tricks for working with UDP multicast MPEG-TS streams on Ubuntu and CentOS. We assume you have a linux server or a workstation with a root (superuser) access and a bunch of multicast streams available in your network. 7 | 8 | #### Checking a multicast UDP stream 9 | Suppose you know incoming UDP MPEG-TS multicast host and port: 10 | 11 | ```sh 12 | udp://233.0.41.102:20000 13 | ``` 14 | In this URL 233.0.41.102 is called IP address (or host) and 20000 is port. We will use these later as an example for configuration settings. 15 | 16 | ### Using tcpdump 17 | 18 | Let’s make sure we are actually receiving a stream using [tcpdump](http://www.tcpdump.org/manpages/tcpdump.1.html). You must be `root` to run `tcpdump`. Execute the following command: 19 | 20 | ```sh 21 | > tcpdump -c 10 dst host 233.0.41.102 and port 20000 and multicast 22 | ``` 23 | This command tells to capture 10 multicast UDP packets sent to host 233.0.41.102 and port 20000. If the stream is running, you shall get something like: 24 | 25 | 26 | ```sh 27 | tcpdump: verbose output suppressed, use -v or -vv for full protocol decode 28 | listening on eth0, link-type EN10MB (Ethernet), capture size 65535 bytes 29 | 15:20:58.818832 IP 43.232.net.50000 > 233.0.41.102.20000: UDP, length 1316 30 | 15:20:58.824080 IP 43.232.net.50000 > 233.0.41.102.20000: UDP, length 1316 31 | 15:20:58.829467 IP 43.232.net.50000 > 233.0.41.102.20000: UDP, length 1316 32 | 15:20:58.835816 IP 43.232.net.50000 > 233.0.41.102.20000: UDP, length 1316 33 | 15:20:58.841053 IP 43.232.net.50000 > 233.0.41.102.20000: UDP, length 1316 34 | 15:20:58.846617 IP 43.232.net.50000 > 233.0.41.102.20000: UDP, length 1316 35 | 15:20:58.852052 IP 43.232.net.50000 > 233.0.41.102.20000: UDP, length 1316 36 | 15:20:58.857893 IP 43.232.net.50000 > 233.0.41.102.20000: UDP, length 1316 37 | 15:20:58.863787 IP 43.232.net.50000 > 233.0.41.102.20000: UDP, length 1316 38 | 15:20:58.869017 IP 43.232.net.50000 > 233.0.41.102.20000: UDP, length 1316 39 | 10 packets captured 40 | 70 packets received by filter 41 | 4 packets dropped by kernel 42 | ``` 43 | If you don’t see output and `tcpdump` seems to freeze, you are not receiving multicast packets. Press `Ctrl-C` to abort `tcpdump` and refer to the next section on firewall settings. 44 | 45 | #### Using netstat 46 | An alternative way to check multicast stream is by using `netstat` tool. You also need to be `root` to use it. 47 | 48 | ```sh 49 | > netstat -a -u -n | grep 233.0.41.102:20000 50 | ``` 51 | If multicast stream is running, you will see: 52 | ```sh 53 | udp 0 0 233.0.41.102:20000 0.0.0.0:* 54 | ``` 55 | (this line may appear twice or more times) 56 | If previous command emits nothing, you are not receiving multicast packets. Refer to the next section on firewall settings. 57 | 58 | #### Firewall and multicast issues with multicast 59 | Very often multicast streams are blocked by firewall. There are various firewalls on linux distributives, we will cover the most popular: `ufw` (Uncomplicated FireWall) for Ubuntu and `iptables` for various distributives. 60 | 61 | Be advised that by misconfiguring the firewall **you may be unable to access your server via SSH!** Disabling firewall at all is highly insecure and **not recommended.** 62 | 63 | #### ufw on Ubuntu 64 | `ufw` is a default firewall for Ubuntu linux. To operate ufw you must be root. 65 | 66 | Check current status of `ufw`: 67 | ```sh 68 | > ufw status 69 | ``` 70 | 71 | If `ufw` is active, add rule to enable receiving multicast on specified host and port: 72 | 73 | ```sh 74 | > ufw allow to 233.0.41.102 port 20000 proto udp 75 | ``` 76 | 77 | You may completely disable `ufw` by typing: 78 | 79 | ```sh 80 | > ufw disable 81 | ``` 82 | This will allow all incoming connections which is insecure and really **not recommended.** Use it only for testing purposes for a limited period of time. 83 | 84 | More info about ufw: `UFW` on [Ubuntu](https://help.ubuntu.com/community/UFW) 85 | 86 | #### iptables 87 | `iptables` is a more complicated firewall and it could be found on Ubuntu, CentOS and many more linux systems. To operate `iptables` you must be root. 88 | 89 | To check `iptables` status run: 90 | 91 | ```sh 92 | > iptables -L 93 | ``` 94 | It will show status and list of the firewall rules. If you have a fresh installation of OS, you should see empty rule chains: 95 | 96 | ```sh 97 | Chain INPUT (policy ACCEPT) target prot opt source destination 98 | 99 | Chain FORWARD (policy ACCEPT) target prot opt source destination 100 | 101 | Chain OUTPUT (policy ACCEPT) target prot opt source destination 102 | ``` 103 | 104 | To allow an incoming multicast stream you need to add a rule by running the following command: 105 | 106 | ```sh 107 | > iptables -A INPUT -p udp -d 233.0.41.102 --dport 20000 -j ACCEPT 108 | ``` 109 | Run `iptables` -L again and you will see: 110 | 111 | ```sh 112 | ACCEPT udp -- anywhere 233.0.41.102 udp dpt:20000 113 | ``` 114 | 115 | `iptables` does not save its status after reboot, so you will need to save newly added rules by typing: 116 | 117 | ```sh 118 | > iptables-save 119 | ``` 120 | More info on `iptables:` 121 | 122 | - [Ubuntu iptables how-to](https://help.ubuntu.com/community/IptablesHowTo) 123 | - [CentOS iptables how-to](https://wiki.centos.org/HowTos/Network/IPTables) 124 | 125 | #### Getting a list of all multicast streams 126 | Sometimes you don’t have list of all multicast streams available. You may get a list of all incoming multicasts quickly by running following simple command: 127 | 128 | ```sh 129 | > sudo tcpdump -n -c 100000 multicast | perl -n -e 'chomp; m/> (\d+.\d+.\d+.\d+).(\d+)/; print "udp://$1:$2\n"' | sort | uniq 130 | ``` 131 | It may take some time to capture 100000 packets and produce output — press `Ctrl-C` if you are tired and reduce amount of packets to capture. 132 | 133 | This will produce a sorted list of incoming multicasts like: 134 | 135 | ```sh 136 | udp://233.0.37.102:20000 137 | udp://233.0.41.102:20000 138 | udp://233.0.42.100:20000 139 | udp://233.0.42.106:20000 140 | udp://233.0.58.114:20000 141 | udp://233.0.58.170:20000 142 | ``` 143 | To make sure it is an actual MPEG-TS stream and read it parameters refer to the next section. 144 | 145 | #### Checking multicast MPEG-TS with ffprobe 146 | `ffprobe` is a versatile utility to check various type of media files and streams. It comes in `ffmpeg` package. 147 | 148 | Install `ffmpeg` (on Ubuntu): 149 | 150 | ```sh 151 | > sudo apt-get install ffmpeg 152 | ``` 153 | Install `ffmpeg` (on CentOS): 154 | ```sh 155 | > sudo yum install ffmpeg 156 | ``` 157 | Use `ffprobe` to check multicast stream: 158 | 159 | ```sh 160 | > ffprobe udp://233.0.41.102:20000 161 | ``` 162 | For a valid MPEG-TS stream you will get something like this: 163 | 164 | ```sh 165 | Input #0, mpegts, from 'udp://233.0.41.102:20000': 166 | Duration: N/A, start: 89651.690400, bitrate: 192 kb/s 167 | Program 10106 168 | Metadata: 169 | service_name : AChannel 170 | service_provider: ChannelProvider 171 | Stream #0:0[0x19a][6]: Audio: mp2 (\[4\]\[0\]\[0\]\[0\] / 0x0004), 48000 Hz, stereo, s16p, 192 kb/s (clean effects) 172 | Stream #0:1[0x145]: Video: mpeg2video (Main) (\[2\]\[0\]\[0\]\[0\] / 0x0002), yuv420p(tv), 720x576 [SAR 64:45 DAR 16:9], max. 15000 kb/s, 25 fps, 25 tbr, 90k tbn, 50 tbc 173 | ``` 174 | Note lines starting with Stream, they contain information about video and audio data: codecs, bitrate, fps etc. 175 | --------------------------------------------------------------------------------