[FFmpeg-devel] [PATCH] avcodec: increase AV_INPUT_BUFFER_PADDING_SIZE to 64

[Carl Eugen Hoyos]

2018-01-08 11:44 GMT+01:00 Reimar Döffinger <Reimar.Doeffinger at gmx.de>:
> On Mon, Jan 08, 2018 at 04:14:22AM +0100, Michael Niedermayer wrote:
>> On Sun, Jan 07, 2018 at 11:42:25PM -0300, James Almer wrote:
>> > On 1/7/2018 11:06 PM, Michael Niedermayer wrote:
>> > > On Sun, Jan 07, 2018 at 01:22:38AM -0300, James Almer wrote:
>> > >> AVX-512 support has been introduced, and even if no functions currently
>> > >> use zmm registers (able to load as much as 64 bytes of consecutive data
>> > >> per instruction), they will be added eventually.
>> > >>
>> > >> Signed-off-by: James Almer <jamrial at gmail.com>
>> > >> ---
>> > >> Same rationale as when it was increased to 32 back in commit
>> > >> 67d29da4bd23057a1f646568442a77b844cb2d1b.
>> > >>
>> > >>  libavcodec/avcodec.h              | 2 +-
>> > >>  libavcodec/x86/hevc_sao.asm       | 2 +-
>> > >>  libavcodec/x86/hevc_sao_10bit.asm | 2 +-
>> > >>  3 files changed, 3 insertions(+), 3 deletions(-)
>> > >
>> > > causes assertion failure:
>> > > ./ffmpeg -i bgc.sub.dub.ogm x.webm
>> > >
>> > > Assertion 64 <= 52 failed at libavformat/oggparseogm.c:109
>> > > Aborted (core dumped)
>> >
>> > How do you say this should be fixed? Why should
>> > AV_INPUT_BUFFER_PADDING_SIZE be lower or equal to 52?
>> >
>> > I have no idea about OGM, so i could use some help.
>>
>> cc-ing reimar, maybe he remembers, the assert seems to come from:
>>
>> commit 7c8d477299c9b5e89fc30ed22f9e42b50761342c
>> Author: Reimar Döffinger <Reimar.Doeffinger at gmx.de>
>> Date:   Mon Feb 6 22:04:46 2012 +0100
>>
>>     Make AAC in Ogg (ogm) work.
>
> The assert probably never made sense (probably left-over from an early
> try that would do the allocation earlier on, in that case we wouldn't have
> needed to reallocate the data to add the padding before storing in
> extradata), but it should have been removed at the latest when the code
> was switched to use ff_alloc_extradata.
> Either way, it should no longer be relevant.

I removed the assert.

Thank you, Carl Eugen