M3U8

This is a most complete opensource library for parsing and generating of M3U8 playlists used in HTTP Live Streaming (Apple HLS) for internet video translations.

Features are:

• Realized HLS specs up to version 3 of the protocol.
• Parsing and generation of master-playlists and media-playlists.
• Offer structures for keeping playlists metadata.
• Encryption keys support for usage with DRM systems like Verimatrix etc.
• Support for non standard Google Widevine tags.

Copyleft Alexander I.Grafov aka Axel grafov@gmail.com

Library licensed under GPLv3.

Install

go get github.com/grafov/m3u8

or get releases from https://github.com/grafov/m3u8/releases

Documentation

Package online documentation (examples included) available at:

• http://gowalker.org/github.com/grafov/m3u8
• http://godoc.org/github.com/grafov/m3u8

Supported by the HLS protocol tags and their library support explained in M3U8 cheatsheet.

Examples

Parse playlist:

	f, err := os.Open("playlist.m3u8")
	if err != nil {
		panic(err)
	}
	p, listType, err := DecodeFrom(bufio.NewReader(f), true)
	if err != nil {
		panic(err)
	}
	switch listType {
	case MEDIA:
	    mediapl := p.(*MediaPlaylist)
		fmt.Printf("%+v\n", mediapl)
	case MASTER:
	    masterpl := p.(*MasterPlaylist)
		fmt.Printf("%+v\n", masterpl)
	}

Then you get filled with parsed data structures. For master playlists you get Master struct with slice consists of pointers to Variant structures (which represent playlists to each bitrate). For media playlist parser returns MediaPlaylist structure with slice of Segments. Each segment is of MediaSegment type. See structure.go or full documentation (link below).

You may use API methods to fill structures or create them manually to generate playlists. Example of media playlist generation:

	p, e := NewMediaPlaylist(3, 10) // with window of size 3 and capacity 10
	if e != nil {
		panic(fmt.Sprintf("Creating of media playlist failed: %s", e))
	}
	for i := 0; i < 5; i++ {
		e = p.Add(fmt.Sprintf("test%d.ts", i), 6.0, "")
		if e != nil {
			panic(fmt.Sprintf("Add segment #%d to a media playlist failed: %s", i, e))
		}
	}
	fmt.Println(p.Encode().String())

Library structure

Library has compact code and bundled in three files:

• structure.go — declares all structures related to playlists and their properties
• reader.go — playlist parser methods
• writer.go — playlist generator methods

Each file has own test suite placed in *_test.go accordingly.

Related links

• http://en.wikipedia.org/wiki/M3U
• http://en.wikipedia.org/wiki/HTTP_Live_Streaming
• http://gonze.com/playlists/playlist-format-survey.html

Library usage

This library successfully used in streaming software developed for my employer and tested with generating of VOD and Live streams and parsing of Widevine Live streams. Also library usage noted in opensource software:

• Stream Surfer monitoring software.
• gohls — HLS downloader.

M3U8 parsing/generation in other languages

• https://github.com/globocom/m3u8 in Python
• https://github.com/zencoder/m3uzi in Ruby
• https://github.com/Jeanvf/M3U8Paser in Objective C
• https://github.com/tedconf/node-m3u8 in Javascript
• http://sourceforge.net/projects/m3u8parser/ in Java
• https://github.com/karlll/erlm3u8 in Erlang

Project status

In development.

for last commit from master or draft branches.

for master branch.

Development rules:

• Changes firstly applied to draft branch then after minimal testing with unit tests it merged with master branch.
• Code in draft branch may be in inconsistent state.
• After complete testing and one week usage with my prober for HLS Stream Surfer it may be released as new library version (minor version number increased).
• Each new API call or tag accompanied by at least one unit test until it released in a new library version.
• Major version number increased on API changes or new tags (until v1.0 this rule is not applied).
• I reserve the right to break the development rules if my life plans make me do it.

Project dashboard: https://waffle.io/grafov/m3u8

Roadmap

For version 0.3:

• Support tags from versions 4 and 5 of the specs.

For version 1.0:

• Support for all M3U8 tags up to latest version of specs.
• Code coverage by unit tests more than 90%