[FFmpeg-devel] [PATCH 2/3 v1.1] avcodec/vaapi: add fields for VAAPI VC-1 interlaced decoding

Carl Eugen Hoyos ceffmpeg at gmail.com
Thu Mar 1 00:42:02 EET 2018

2018-02-28 9:48 GMT+01:00 Jerome Borsboom <jerome.borsboom at carpalis.nl>:

>> Is this expected to pass the two fate tests for VC-1 interlaced,
>> fate-vc1_sa10143 and fate-vc1_ilaced_twomv?  (It doesn't on
>> my system, all output frames are different.)  If not, could you
>> explain why not?

They are expected to change for compliant decoders.

> I have a feeling that the software decoder in FFmpeg is not
> fully compliant with the VC-1 spec.

Your suspicion is correct, the software decoder is not compliant,
fate tests are not relevant for this use-case.

I believe the mailing list archive contains the correct values
but it is simpler to wait for Hendrik to confirm.

> The loopfilter, as currently implemented, may be wrong
> for interlaced content. I am still investigating this issue.

This also sounds correct, could be checked with the
reference decoder and -skip_loop_filter.

Carl Eugen

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