[FFmpeg-devel] [PATCH] h264 - don't warn about deblocking type 1 without multiple slices

Andreas Öman andreas
Sat Oct 27 12:13:07 CEST 2007

Alexander Strange wrote:
> If you enable multithreaded decoding for h.264, you get the warning
> "Cannot parallelize deblocking type 1, decoding such frames in 
> sequential order",
> even if the video has only one slice and can't be parallelized anyway.
> This patch disables that bit of code for the first slice in a frame. I 
> tested it on
> single-slice (that it can't parallelize) and multi-slice (that it can), 
> but not on
> type 1 + multi-slice since I can't find any. Is there any on mplayerhq?

Dunno about mphq, but apples movietrailers are 1 + multi_spice, and
for those files the warning is still printed with your patch (as
expected I guess)

Having said that, I'm a little in doubt if the line should be around
at all (in the current form) since there are various other types of
content that cannot be parallelized (which it dont "warn" abount).

Perhaps it should be extended to warn if a user requests
multithreading but the content is single-sliced.

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