[Ffmpeg-devel] Mpeg2-ts encoder uses fixed PES payload size

Kling, Fredrik Fredrik.Kling
Mon Feb 26 17:04:14 CET 2007


I have noticed that the MPEG2 TS Encoder (mpegtsenc.c in libavformat)
uses a fixed size buffer for the PES data. 
Is there a reason for this ?

Ex: ffmpeg -i videofile.264 -vcodec copy -f mpegts file.mpegts

Will produce quite a data-overhead due to ineffective PES handling.
Changing the PES handling to using the size (supplied by the AVPacket
structure, in function mpegts_write_packet) and reallocating properly
would allow for dynamic payload sizes instead of fixed.

Some other 'issues' found:
- The current mpegtsenc.c can not handle VC-1
- the SDT packet frequence seems quite flawed (adding an SDT packet
every second packet!), causing the TS to grow up to 64% bigger than the
actual ES it encapsulates...

Having no experience in supplying patches I am just wondering if someone
is intrested in the fixes, or if I should just keep it to myself...

Best Regards
Fredrik Kling

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