Hi. I'm trying to detect the VAAPI JPEG decoder capabilities using
vaQueryConfigAttributes(). I'm getting VA_RT_FORMAT_YUV420 as the only value
for VAConfigAttribRTFormat when the profile is VAProfileJPEGBaseline and the
entrypoint is VAEntrypointVLD. However, based on [1], it seems that the JPEG
decoder would be happy to decode YUV422 images (in fact, YUV422 decoding works
when I call vaCreateSurfaces() with VA_RT_FORMAT_YUV422).

Note that when I use vaQuerySurfaceAttributes(), I only get NV12 for
VASurfaceAttribPixelFormat, so YUV422 is also not advertised there.

Is this intended behavior?

[1]
https://gitlab.freedesktop.org/mesa/mesa/blob/master/src/gallium/state_trackers/va/picture.c#L607-610