[FFmpeg-devel] [PATCH] Setup for extracting quantization parameters from encoded streams

[Lynne]

Jul 22, 2019, 8:03 PM by juandl-at-google.com at ffmpeg.org:

> On Fri, Jul 19, 2019 at 12:47 PM Moritz Barsnick <barsnick at gmx.net> wrote:
>
>> On Fri, Jul 19, 2019 at 10:00:52 +0200, Nicolas George wrote:
>> > I do not judge whether this filter would be useful and should be
>> > included, but if so, then I would appreciate that the output be done
>> > using AVIO, so that it can go to any supported protocol.
>>
>> The metadata filter has a nice example of how to use avio, incl.
>> mapping to stdout:
>>
>>
>> https://github.com/FFmpeg/FFmpeg/blob/f102a4efcef33014d414f9bf4492a04feab20c82/libavfilter/f_metadata.c#L250
>>
>> I suppose this can been used as a reference.
>>
>> Moritz
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>
>
> Thanks, I will update the filter to use avio.
> Pinging the thread.
>

I've explained why this is a bad idea and why you should maintain it internally.
You can't hack a decoder in any nice and performant way for it to output data to an analyzer.