I checked the specs. Never mind me.

Regarding intra_dc_precision: [8-10] for Simple, Main, SNR & Spatial. [8-11] 
for High. :(

Seems the chip only supports VAProfileMPEG2Main and not VAProfileMPEG2High.

Kind regards, Andreas Larsson

> Info on how to reproduce it with very little effort: 
> 
> Convert some movie into m2v and force intra dc precision to 11:
> ffmpeg -i somemovie -sameq -dc 11 out_11.m2v
> 
> on unit simply play it using vaapi:
> mplayer -vo vaapi -va vaapi out_11.m2v 
> 
> The DC-levels on the I-frames are completely off. Using -dc 10 on the ffmpeg 
> line will produce a movie that is perfectly playable.
> 
> I assume the problem lies either in the va-backend (driver), in the micro 
> code of the chip (driver binary blob) or in the chip itself (HW problem). Can 
> you confirm?
> 
> Also I haven't read the MPEG2 spec closely enough to confirm that a intra dc 
> precision value of 3 (i.e. 11 bits) are ok when using main profile...
> 
> Kind regards, Andreas Larsson
> 
>> Another problem I've stumbled upon is that when using intra_dc_precision = 3 
>> (i.e. 11-bit DC-predictors) the chip doesn't decode the stream properly. The 
>> DC levels are completely off both in luma and in chroma. Decoding the same 
>> stream using VLC or software mplayer etc displays it correctly.
>> 
>> VA: v0.31.1 VAProfileMPEG2Main + VAEntrypointVLD
>> CPU : Intel ATOM Z510
>> GFX: Intel US15W
>> OS: Linux Fedora 14
>> X.Org: X.Org X Server 1.9.4
>> GFX-driver: Intel(R) Embedded Media and Graphics Driver version 1.14.2443
>> 
>> Switching to intra_dc_precision = 2 (i.e. 10-bit DC predictors) decodes 
>> correctly though. Do you have any erratas on this or any helpful insights?
>> 
>> Kind regards, Andreas Larsson
> 
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