hmm since I'm not able to edit:
I've now got vainfo to return something useful. I did this by the following two commands:
after which vainfo returned:
sudo ln -s /usr/lib/va/drivers/fglrx_drv_video.so /usr/lib/fglrx/dri/fglrx_drv_video.so
However, when playing a h264 file, I get garbled output, as well as the following message among the output, which I think indicates what's wrong, but I have no idea how to fix it...
libva: libva version 0.31.0
libva: va_getDriverName() returns 0
libva: Trying to open /usr/lib/fglrx/dri/fglrx_drv_video.so
libva: va_openDriver() returns 0
vainfo: VA API version: 0.31
vainfo: Driver version: Splitted-Desktop Systems XvBA backend for VA-API - 0.7.7
vainfo: Supported profile and entrypoints
VAProfileH264High : VAEntrypointVLD
VAProfileVC1Advanced : VAEntrypointVLD
Unsupported PixelFormat 61
[VD_FFMPEG] Trying pixfmt=1.