VLC VAAPI

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Introduction to GPU decoding in VLC

The VLC framework can use your graphic card (aka GPU) to decode H.264 streams (wrongly called HD videos) under certain circumstances.

VLC, in its modular approach and its transcoding/streaming capabilities, does decoding in GPU at the decoding stage only and then gets the data back to go to the other stages (streaming, filtering or plug any video output after that).

What that means is that, compared to some other implementation, GPU decoding in VLC can be slower because it needs to get the data back from the GPU. But you can plug ANY video output (sink) to it and use all the VLC video filters.


Introduction to compilation of VAAPI in VLC

This page is about compiling VLC with support of GPU acceleration on Linux. For Windows, look at VLC_DxVA2.

This howto has been written by Jean-Baptiste Kempf and tested with nVidia GPU.

http://en.wikipedia.org/wiki/Video_Acceleration_API

http://www.freedesktop.org/wiki/Software/vaapi

Before starting

libva

Install libva from http://www.splitted-desktop.com/~gbeauchesne/libva/ . We do not support other libraries than the one from Mr Beauchesne.

Drivers

nVidia

http://www.splitted-desktop.com/~gbeauchesne/vdpau-video/ for nVidia.

Patch it with http://mailman.videolan.org/pipermail/vlc-devel/attachments/20100109/2cb302b3/attachment.patch

ATI

http://www.splitted-desktop.com/~gbeauchesne/xvba-video/ for ATI.

Run

vainfo

To check if everything works.

FFmpeg trunk

Get the latest FFmpeg trunk as of 2010-January. Compile it with vaapi hwaccel support.

./configure --enable-gpl --enable-postproc --prefix=/path/to/ --enable-shared --enable-vaapi
make
make install

Copy vaapi.h to the includes.

VLC

Get VLC from Git. Get the necessary external libraries (on debian/*buntu: apt-get build-dep vlc)

./bootstrap
./configure
make


Compile VLC with vaapi

Patch VLC with http://vlc.pastebin.com/f59445620

Reconfigure VLC.

Edit vlc-config and add

-lX11 -lva-x11

to the avcodec line.

Mine looks like this:

avcodec)
     cflags="${cflags} -I/home/jb/VideoLAN/vlc/vlc/extras/ffmpeg"
     libs="${libs} /home/jb/vlc/extras/ffmpeg/libavcodec/libavcodec.a /home/jb/vlc/extras/ffmpeg/libavutil/libavutil.a -lz -lm -lva -ldl -ljack -lasound -lm -lX11 -lva-x11"

Recompile VLC

make clean && make

Check

That everything went ok:

./vlc --list | grep avcodec

should return something.

Activate

Activate acceleration in the preferences.

Profit