[FFmpeg-devel] [PATCH] Fix de/selection of libx264 I-partitions

Panagiotis Issaris takis.issaris
Fri Jul 27 11:36:51 CEST 2007

Panagiotis Issaris schreef:
> Panagiotis Issaris schreef:
>> Hi,
>> Loren Merritt wrote:
>>> On Thu, 26 Jul 2007, Panagiotis Issaris wrote:
>>>> I've noticed that when using ffmpeg, using -partitions -parti4x4 doesn't
>>>> work as I had expected. Although I was trying to disable the generations
>>>> of 4x4 blocks, the output of ffmpeg would still contain:
>>>> ...
>>>> mb I  I16..4: 59.1%  0.0% 40.9%
>>>> ...
>>>> The attached patch fixes the selection and deselection of the usage of
>>>> certain blocksizes when using libx264.
>>> ffmpeg is currently consistent with mencoder and x264cli: the "partitions" 
>>> option affects only P- and B-frames, while I-frames always use all 
>>> available partitions. Because the only reason for disabling partitions is 
>>> speed, and intra partitions in I-frames gain much more compression per 
>>> cpu-time than in P- and B-frames.
>>> If you want some way to disable partitions in I-frames, that's another 
>>> question. But don't change the meaning of an existing option.
>> Ah, I see. Well, from a user point of view, it seemed logical to me that
>> disabling I4x4 blocks would do so in both I and P frames, but I also
>> think my patch was wrong in that sense too. It should have also kept
>> OR-ing analyse.inter with the I4x4's and I8x8's as I now always entirely
>> disabled them for P frames, right?
>> I'll try to prepare a different patch, introducing a way to disable them
>> for I frames, without changing existing options.
> Attached a patch introducing new parameters for -partitions, being
> "parti4x4i" and "parti8x8i". The patch does alter the current behavior
> as with this patch 4x4 and 8x8 partitions for I frames aren't used
> anymore by default. Any thoughts on that?
>  avcodec.h |    2 ++
>  libx264.c |    8 ++++++++
>  utils.c   |    2 ++

Reindent after this patch.

 avcodec.h |   10 +++++-----
 1 files changed, 5 insertions(+), 5 deletions(-)

With friendly regards,
vCard: http://issaris.org/pi.vcf
PGP key: http://issaris.org/pi.key
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