[FFmpeg-devel] [PATCH] ffmpeg: switch to avformat_seek_file for stream_loop

[Gyan]

On 05-09-2019 10:50 PM, Michael Niedermayer wrote:
> On Wed, Sep 04, 2019 at 03:47:50PM +0530, Gyan wrote:
>>
>> On 02-09-2019 09:24 PM, Michael Niedermayer wrote:
>>> On Sat, Aug 31, 2019 at 08:28:51PM +0530, Gyan wrote:
>>>> A user observed that stream_loop didn't work with very short FLV files.
>>>> seek_to_start in ffmpeg.c calls av_seek_frame with no flags; FLV seek only
>>>> works with RTMP protocol so lavf falls back on seek_frame_generic which
>>>> searches forward, skipping a GOP. With files with two index entries in
>>>> stream, the file doesn't loop at all.
>>>>
>>>> I switched to avformat_seek_file which will set the BACKWARDS flag when
>>>> seeking to start of file. stream_loop works and no frames are dropped.
>>>>
>>>> FATE passes.
>>>>
>>>> Gyan
>>>>   ffmpeg.c |    2 +-
>>>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>>> c79dc6d27a9c8c1bd0cffa2d251b2aa7caf23bf3  0001-ffmpeg-switch-to-avformat_seek_file-for-stream_loop.patch
>>>>  From 4af64f612c65378f0a220284ca99ad033ece8cd3 Mon Sep 17 00:00:00 2001
>>>> From: Gyan Doshi <ffmpeg at gyani.pro>
>>>> Date: Sat, 31 Aug 2019 19:45:58 +0530
>>>> Subject: [PATCH] ffmpeg: switch to avformat_seek_file for stream_loop
>>>>
>>>> Fixes stream_loop with very short files where seeking is generic index
>>>> search
>>>> ---
>>>>   fftools/ffmpeg.c | 2 +-
>>>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>> probably ok
>>>
>>> it also might make sense to add the testcase to fate as you mentioned "short"
>>>
>> New patches attached. Will send file to samples-request.
>>
>> Gyan
>>   ffmpeg.c |    2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>> a05d0f2f099a64aa3d749a6fbd0617c0bf24ab3b  0001-ffmpeg-switch-to-avformat_seek_file-for-stream_loop.patch
>>  From 953c9c11d90aa69121825284d5f6bf0c34793b2d Mon Sep 17 00:00:00 2001
>> From: Gyan Doshi <ffmpeg at gyani.pro>
>> Date: Sat, 31 Aug 2019 19:45:58 +0530
>> Subject: [PATCH 1/2] ffmpeg: switch to avformat_seek_file for stream_loop
>>
>> Fixes stream_loop with very short files where seeking is generic index
>> search
>> ---
>>   fftools/ffmpeg.c | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
> Tested on x86 linux 32/64bit, mingw 32/64, qemu mips & arm

Pushed as

   fa697aa92f5dfebda11d53db971ec4ac6c517008 and
   2b66c757d6aa3a9feee4d25b587becd366c868f1

Thanks,
Gyan