[FFmpeg-devel] [RFC] BSF list API

[Marton Balint]

Hi All,

My GSOC student Jan is working on improving the tee muxer, and as a side 
project he is also working on converting the tee muxer to the new BSF API.

I have checked his WIP patches, and it seems to me that developing some 
API which we can use for BSF chains would be really useful not only for 
the tee muxer, but for a lot of other places (e.g. ffmpeg.c) as well.

Instead of adding a totally new API, I suggest to use a "container" 
bitstream filter called 'list', which will instantiate the 
"child" bitstream filters and pump the packets through them.

Thanks to the N:M nature of the new BSF api, this should be achievable, 
and we can completely hide for the API user if we are using a single 
bitstream filter, or a chain (list) of several bitstream filters.

The mentioned 'list' bitstream filter could have an AVOption string 
parameter called list which it can parse on init to create the bitstream 
filter chain. The list string would follow the ffmpeg bsf list syntax:
filter1[=opt1=str1/opt2=str2][,filter2]

The list bitstream filter with and empty list can also work as the null 
bitstream filter already discussed on this mailing list.

Please comment, thanks,

Marton