[VDPAU] [RFC] [PATCH 0/3] Missing H.264 profiles

[Rémi Denis-Courmont]

     Hello,

The current VDPAU headers only define three profiles for H.264: 
Baseline, Main and High. It is ambiguous which profile an application 
should request for decoding Constrained Baseline content. Constrained 
Baseline is a subset of Baseline and a subset of Main, but neither 
Baseline nor Main are a subset of the other.

This has led to this bug when combining VLC and libav(codec): 
https://bugzilla.libav.org/show_bug.cgi?id=757

So here I am proposing to define some more profiles (patch 2). Only 
profiles for 8-bits per component, 4:2:0 chroma subsampling, 
"monoscopic" and single-layered content are included. Other profiles 
would need further separate extensions to surface chroma types or such.

The third patch provides backward compatibility with existing/old VDPAU 
back-end drivers by transparently remapping the codec profile to any 
strict superset profile. For instance, if Constrained Baseline is 
unsupported/unknown, this will automatically try to use Baseline or 
Main.

Feedback welcome.

-- 
Rémi Denis-Courmont