[FFmpeg-devel] [PATCH] When PMT is found, we have found mpegts header information

elupus elupus
Sat Apr 17 14:49:16 CEST 2010

On Fri, 16 Apr 2010 13:41:08 -0700, Baptiste Coudurier wrote:

> On 04/16/2010 01:33 PM, elupus wrote:
>> [16 quoted lines suppressed]
> I'm sure a smaller probesize would be reasonable and would work in most 
> of the cases.
>> [6 quoted lines suppressed]
> AVFMT_NOHEADER is handled in av_find_stream_info, and this process is 
> stopped by probesize.
> AVFMT_NOHEADER is here to inform the user that new streams can be added 
> later on.

> PMT is not found during av_find_stream_info specifically, it is found 
> during the demuxing.
> av_find_stream_info keeps reading some packets until probesize is 
> reached to detect as many streams as possible, due to AVFMT_NOHEADER.
> If you remove AVFMT_NOHEADER, there is a great chance some streams will 
> be missed.

They will only be missed if they are not in the first PMT. And imho the
chance of multiple pmt to show up in the first 5mb (as beeing the default
probesize) of a file compared to the rest of the file is quite small. 

They will however totaly be missed if we reduce probesize and pmt shows up
later. But i'll keep it local to xbmc for now, until ffmpeg get's a new
mpegts demuxer :)


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