[FFmpeg-devel] [PATCH] increase AVStream pts_buffer size

[Baptiste Coudurier]

Hi Michael,

Michael Niedermayer wrote:
> On Sat, Aug 09, 2008 at 05:34:51PM -0700, Baptiste Coudurier wrote:
>> Baptiste Coudurier wrote:
>>> M?ns Rullg?rd wrote:
>>>> Baptiste Coudurier <baptiste.coudurier at smartjog.com> writes:
>>>>
>>>>> Hi,
>>>>>
>>>>> H264 decoder can (now?) set has_b_frames to MAX_DELAYED_PIC_COUNT which
>>>>> is 16, need to port this to pts_buffer in AVStream struct.
>>>>>
>>>>> compute_pkt_files in utils.c:
>>>>> int delay = FFMAX(st->codec->has_b_frames, !!st->codec->max_b_frames);
>>>>>
>>>>> [...]
>>>>>
>>>>> //calculate dts from pts
>>>>> if(pkt->pts != AV_NOPTS_VALUE && pkt->dts == AV_NOPTS_VALUE){
>>>>>     st->pts_buffer[0]= pkt->pts;
>>>>>     for(i=1; i<delay+1 && st->pts_buffer[i] == AV_NOPTS_VALUE; i++)
>>>>>         st->pts_buffer[i]= (i-delay-1) * pkt->duration;
>>>>>     for(i=0; i<delay && st->pts_buffer[i] > st->pts_buffer[i+1]; i++)
>>>>>         FFSWAP(int64_t, st->pts_buffer[i], st->pts_buffer[i+1]);
>>>>>      pkt->dts= st->pts_buffer[0];
>>>>> }
>>>>>
>>>>> Patch attached.
>>>>>
>>>>> Index: libavformat/avformat.h
>>>>> ===================================================================
>>>>> --- libavformat/avformat.h	(revision 14513)
>>>>> +++ libavformat/avformat.h	(working copy)
>>>>> @@ -385,7 +385,7 @@
>>>>>  
>>>>>      int64_t nb_frames;                 ///< number of frames in this stream if known or 0
>>>>>  
>>>>> -#define MAX_REORDER_DELAY 4
>>>>> +#define MAX_REORDER_DELAY 16
>>>>>      int64_t pts_buffer[MAX_REORDER_DELAY+1];
>>>>>  
>>>>>      char *filename; /**< source filename of the stream */
>>>> This breaks ABI, so it needs a version bump.  Others can have an
>>>> opinion on how bad that is.
>>>>
>>> Right, we can avoid going too far in the mean time to avoid breaking
>>> ABI, it is not the right solution I believe but it should fix the bug,
>>> patch attached.
>>>
>>>
>>>
>>> ------------------------------------------------------------------------
>>>
>>> Index: libavformat/utils.c
>>> ===================================================================
>>> --- libavformat/utils.c	(revision 14513)
>>> +++ libavformat/utils.c	(working copy)
>>> @@ -2472,7 +2472,7 @@
>>>      //calculate dts from pts
>>>      if(pkt->pts != AV_NOPTS_VALUE && pkt->dts == AV_NOPTS_VALUE){
>>>          st->pts_buffer[0]= pkt->pts;
>>> -        for(i=1; i<delay+1 && st->pts_buffer[i] == AV_NOPTS_VALUE; i++)
>>> +        for(i=1; i<delay+1 && i < MAX_REORDER_DELAY+1 && st->pts_buffer[i] == AV_NOPTS_VALUE; i++)
>>>              st->pts_buffer[i]= (i-delay-1) * pkt->duration;
>>>          for(i=0; i<delay && st->pts_buffer[i] > st->pts_buffer[i+1]; i++)
>>>              FFSWAP(int64_t, st->pts_buffer[i], st->pts_buffer[i+1]);
>>>
>> Any comments ? This fixes a bug :>
> 
> too fe hours each day ... :)
> 
> i think there ae 2 issues here.
> first is that MAX_REORDER_DELAY is too small, that can be fixed adding a
> new pts_buffer at the end of AVStream that is bigger and putting the old
> one under #if VERSION<...
> 

Thanks for review, patch attached.

-- 
Baptiste COUDURIER                              GnuPG Key Id: 0x5C1ABAAA
Smartjog USA Inc.                                http://www.smartjog.com
Key fingerprint                 8D77134D20CC9220201FC5DB0AC9325C5C1ABAAA
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