1# Enabling hardware <video> decode codepaths on linux 2 3Hardware acceleration of video decode on Linux is 4[unsupported](https://crbug.com/137247) in Chrome for user-facing builds. During 5development (targeting other platforms) it can be useful to be able to trigger 6the code-paths used on HW-accelerated platforms (such as CrOS and win7) in a 7linux-based development environment. Here's one way to do so, with details based 8on a gprecise setup. 9 10* Install pre-requisites: On Ubuntu Precise, at least, this includes: 11 12 ```shell 13 sudo apt-get install libtool libvdpau1 libvdpau-dev 14 ``` 15 16* Install and configure [libva](http://cgit.freedesktop.org/libva/) 17 18 ```shell 19 DEST=${HOME}/apps/libva 20 cd /tmp 21 git clone git://anongit.freedesktop.org/libva 22 cd libva 23 git reset --hard libva-1.2.1 24 ./autogen.sh && ./configure --prefix=${DEST} 25 make -j32 && make install 26 ``` 27 28* Install and configure the 29 [VDPAU](http://cgit.freedesktop.org/vaapi/vdpau-driver) VAAPI driver 30 31 ```shell 32 DEST=${HOME}/apps/libva 33 cd /tmp 34 git clone git://anongit.freedesktop.org/vaapi/vdpau-driver 35 cd vdpau-driver 36 export PKG_CONFIG_PATH=${DEST}/lib/pkgconfig/:$PKG_CONFIG_PATH 37 export LIBVA_DRIVERS_PATH=${DEST}/lib/dri 38 export LIBVA_X11_DEPS_CFLAGS=-I${DEST}/include 39 export LIBVA_X11_DEPS_LIBS=-L${DEST}/lib 40 export LIBVA_DEPS_CFLAGS=-I${DEST}/include 41 export LIBVA_DEPS_LIBS=-L${DEST}/lib 42 make distclean 43 unset CC CXX 44 ./autogen.sh && ./configure --prefix=${DEST} --enable-debug 45 find . -name Makefile |xargs sed -i 'sI/usr/lib/xorg/modules/driversI${DEST}/lib/driIg' 46 sed -i -e 's/_(\(VAEncH264VUIBufferType\|VAEncH264SEIBufferType\));//' src/vdpau_dump.c 47 make -j32 && rm -f ${DEST}/lib/dri/{nvidia_drv_video.so,s3g_drv_video.so} && make install 48 ``` 49 50* Add to args.gn: 51 * `target_os = "chromeos"` to link in `VaapiVideoDecodeAccelerator` 52 * `proprietary_codecs = true` and `ffmpeg_branding = "Chrome"` to 53 allow Chrome to play h.264 content, which is the only codec 54 VAVDA knows about today. 55* Rebuild chrome 56* Run chrome with `LD_LIBRARY_PATH=${HOME}/apps/libva/lib` in the environment, 57 and with the `--no-sandbox` command line flag. 58* If things don't work, a Debug build (to include D\*LOG's) with 59 `--vmodule=*content/common/gpu/media/*=10,gpu_video*=1` might be 60 enlightening. 61 62** note 63NOTE THIS IS AN UNSUPPORTED CONFIGURATION AND LIKELY TO BE BROKEN AT ANY 64POINT IN TIME 65** 66 67This page is purely here to help developers targeting supported HW `<video>` 68decode platforms be more effective. Do not expect help if this setup fails to 69work. 70