View source for VLC VAAPI

{{wikipedia|Video Acceleration API}} 

== Introduction to GPU decoding in VLC  ==
{{See also|VLC GPU Decoding}}

The VLC framework can use your '''''graphic card''''' (aka GPU) to decode H.264 streams (wrongly called HD&nbsp;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]].<br>

This howto has been written by [[User:J-b|Jean-Baptiste Kempf]] and tested with nVidia GPU. 

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

== Before starting  ==

=== libva  ===

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

=== Drivers  ===

==== nVidia  ====

http://www.splitted-desktop.com/~gbeauchesne/vdpau-video/ for nVidia.{{dead link}}  Use at least version 0.6.2.

==== ATI  ====

http://www.splitted-desktop.com/~gbeauchesne/xvba-video/ for ATI.{{dead link}} Use at least 0.6.4.

Check if LIBVA environment variables are correctly configured:

 set | grep LIBVA

Should output something like:

 LIBVA_DRIVER_NAME=xvba
 LIBVA_DRIVERS_PATH=/usr/lib64/va/drivers

If not, add these, according to your library path, to your system environment variables (/etc/environment ?)

Then run 

 vainfo

which should return something like:

 VAProfileH264High               :	VAEntrypointVLD
 VAProfileVC1Advanced            :	VAEntrypointVLD

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, if not done (newer FFmpeg should do that automagically)

=== VLC  ===

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

 ./bootstrap
 ./configure
 make

<br> 

== Compile VLC with vaapi  ==

Configure VLC. 

Edit vlc-config and add 

 -lX11 -lva-x11

to the avcodec line. (Step no longer required with recent builds)

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 &amp;&amp; make

=== Check  ===

That everything went ok: 

 ./vlc --list | grep avcodec

should return something.

== Activate  ==

Activate acceleration in the preferences. 

Or directly on command line

 vlc --ffmpeg-hw

Exemple: on playback log output (with -v debug and ATI VAAPI)

 [0x7f8c4cc03ba8] avcodec decoder: Using VA API version 0.32 for hardware decoding.

Profit

[[Category:Building]]
[[Category:GNU/Linux]]
[[Category:How To]]