[Libva] [PATCH 0/2] Fix support for H.264 implicit weight tables (SNB)

Gwenole Beauchesne gb.devel at gmail.com
Tue Mar 13 11:54:23 PDT 2012


Hi,

I have pushed the following patches to git master. This fixes:
<https://bugs.freedesktop.org/show_bug.cgi?id=40820>

- weighted prediction indicator was incorrect for Sandy Bridge;
- if implicit weight tables are used, the HW miscomputes logWDc.

I am not sure if the latter is a HW bug, but I'd expect that if implicit weight
tables are used, the correct derivation values are to be used in that case.
However, HW still relies on user-provided {luma,chroma}_log2_weight_denom, which
can be random values since those are supposed to only exist from pred_weight_table().

Quick testing shows that Ivy Bridge and Cedar Trail platforms have no issue with that.

Regards,
Gwenole Beauchesne (2):
  h264: fix weighted prediction indicator (SNB).
  h264: fix weight denom for implicit weight tables (SNB).

 NEWS           |    1 +
 src/gen6_mfd.c |   16 +++++++++++++---
 2 files changed, 14 insertions(+), 3 deletions(-)

-- 
1.7.5.4



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