>
> This is also what I noticed, when playing with probesize and analyzeduration 
> trying to get the player to start more quickly (using mpegts (h264/aac) 
> streams served through a memory buffer).
>
> This leads to the question why does a known stream need to get probed / 
> analyzed at all? If all values are known, they could be set before, and 
> decoding / playing should start right away, skipping the step of 
> av_find_stream_info. Unfortunately so far I did not manage to get this to 
> work, av_find_stream_info seems to set something which is required for 
> decoding to work.
>
> I looked though the av_find_stream_info source code and did not find anything 
> special happening there, or I did not recognize it.
>
> So, to reduce latency, what has to be set for a codec / context to allow to 
> skip the time-consuming step of av_find_stream_info?


Just one thing I wanted to mention:

When I am opening a file I call avformat_open_input, then after that I
call avformat_find_stream_info, and I am timing those calls:

'avformat_open_input':          9.7970 seconds
'avformat_find_stream_info':  0.1080 seconds

So for me the problem seems to be avformat_open_input. My testfiles
are all around that range, maybe +-2 sec

As I mentioned before, changine probesize/analyzeduration from 5000000
to 5000 doesn't seem show any visible effect (just ranging within the
usual fluctuations of the above timings)

Is that what you experienced too?

-Bjoern
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