[FFmpeg-devel] [PATCH 0/2]: allow hwaccel vda module to manage its buffers lifetime.

[Sebastien Zwickert]

On May 23, 2013, at 8:29 AM, Hendrik Leppkes <h.leppkes at gmail.com> wrote:
> On Wed, May 22, 2013 at 9:53 PM, Sebastien Zwickert <dilaroga at gmail.com> wrote:
>> This patchset fixes memory leaks of vda core video buffers while seeking.
>> It allows hwaccel modules to set a custom callback for freeing av buffers.
>> Then vda decoder can flush correctly dropped frames.
>> 
>> Thanks to Xidorn Quan who gives me good feebacks about the patch I shared
>> with him in private.
>> 
>> Sebastien Zwickert (2):
>>  hwaccel: allow to set a user-defined callback for releasing private
>>    av buffer.
>>  vda: use hwaccel custom callback for releasing private picture
>>    context.
>> 
>> libavcodec/avcodec.h   |   12 ++++++++++++
>> libavcodec/h264.c      |    9 ++++++++-
>> libavcodec/mpegvideo.c |    9 ++++++++-
>> libavcodec/vda.h       |   12 +++++++++++-
>> libavcodec/vda_h264.c  |   18 ++++++++++++++++++
>> 5 files changed, 57 insertions(+), 3 deletions(-)
>> 
>> --
>> 1.7.9.6 (Apple Git-31.1)
>> 
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> 
> You set frame->data[3] to the same buffer that needs freeing, why not
> simply also set frame->buf appropriately to a AVBufferRef you create,
> so that it gets free'ed with a callback there?
> No extra release buffer callback needed from where i stand.

I'm not sure to understand correctly but the vda buffer is part of
Core Video SDK which is based on a ref counted memory management
and must be released with CVPixelBufferRelease().
So custom callback for freeing Core Video types is necessary.