README.md

libvpx-go

Package vpx provides Go bindings for libvpx-1.8.0, the WebM Project VPx codec implementation. All the binding code has automatically been generated with rules defined in vpx.yml.

Usage

$ brew install libvpx # >= 1.8
$ brew install pkg-config
# (or use your package manager)

$ go get github.com/xlab/libvpx-go/vpx

Demo application

There is a simple WebM player with support of VP8/VP9 video and Vorbis/Opus audio implemnted, see cmd/webm-player. To get videos to play you can use youtube-dl tool that is very convenient. It supports all the formats that are in WebM container, the player would automatically find video andaudio streams in a single file or in both (only video + only audio), see usage examples below.

Install deps (demo app)

See also GLFW for Windows installation guide at github.com/golang-ui/nuklear.

$ brew install libvpx # >= 1.8
$ brew install libogg libvorbis opus portaudio
# (or use your package manager)

$ go get github.com/xlab/libvpx-go/cmd/webm-player

$ webm-player -h
A simple WebM player with support of VP8/VP9 video and Vorbis/Opus audio. Version: v1.0rc1

Usage: webm-player <file1.webm> [file2.webm]

For Linux (e.g. Debian Sid):

$ apt-get install libvpx-dev libogg-dev libvorbis-dev libopus-dev portaudio19-dev
$ go get github.com/xlab/libvpx-go/cmd/webm-player

Software used

There is a list of libraries used to build this app:

• go-gl/glfw — Go bindings for multi-platform library for OpenGL, OpenGL ES and Vulkan development, used here to init the GL context, window and handle the input events;
• golang-ui/nuklear — Go bindings for nuklear.h — a small ANSI C GUI library, used here to build the GUI layout, display the video frame as image, handle events sent by GLFW;
• ebml-go/ebml — a pure Go implementation of an EBML decoder (by Jorge Acereda Macia);
• ebml-go/webm — a pure Go implementation of a parser, reader and seeker for WebM container, uses EBML to decode the WebM metadata (by Jorge Acereda Macia);
• libvpx — Go bindings for libvpx-1.8.0, the WebM Project VP8/VP9 codec implementation;
• vorbis — Go bindings for OggVorbis implementation by the Xiph.Org Foundation;
• opus — Go bindings for Opus implementation by the Xiph.Org Foundation;
• portaudio — Go bindings for PortAudio, a free, cross-platform, open-source, audio I/O library.

Usage

Please keep in mind that this actually is a VP8/VP9 decoding demo, yet though it does audio decoding well too. Video frames are converted to RGBA using a software decoder (a function), moving that to GPU would give it a boost for 720p+ resolutions, but this is left as an excercise for you, pull requests are welcome. Also audio synchronisation is poor, I invested a couple of hours but I'm lazy to get it done right. Also no pause button, sorry.

$ youtube-dl -F w2DpLW374Sg # list all formats
$ youtube-dl -f 247 w2DpLW374Sg # webm 1280x720 vp9, 30fps, video only, 71.90MiB
$ youtube-dl -f 251 w2DpLW374Sg # webm audio only, opus @160k (48000Hz), 8.92MiB

$ webm-player ~/Downloads/w2DpLW374Sg.webm ~/Downloads/w2DpLW374Sg_opus.webm
2016/09/27 21:43:38 glfw: created window 800x500
2016/09/27 21:43:38 webm: found video track: 1280x720 dur: 9m54s V_VP9
2016/09/27 21:43:38 webm: found audio track: ch: 2 48000.0Hz, dur: 9m54s, codec: A_OPUS
2016/09/27 21:43:38 [INFO] took Video from the first stream, Audio from the second

$ youtube-dl -f 43 5kj5ApnhPAE # webm  640x360   medium , vp8.0,  vorbis@128k

$ webm-player ~/Downloads/5kj5ApnhPAE.webm
2016/09/27 21:40:43 glfw: created window 800x500
2016/09/27 21:40:43 webm: found video track: 640x360 dur: 12m30s V_VP8
2016/09/27 21:40:43 webm: found audio track: ch: 1 44100.0Hz, dur: 12m30s, codec: A_VORBIS

FAQ

Does it support rick roll?

Yes, it does.

Rebuilding the package

You will need to get the c-for-go tool installed first.

$ git clone https://github.com/xlab/libvpx-go && cd libvpx-go
$ make clean
$ make

License

All the code except when stated otherwise is licensed under the MIT license.