Re: [Kdenlive-devel] IPB frame order and possible link to my "jerking" video?

[Dan D. <da...@de...>]

On Wednesday 06 June 2007 19:11, Jan Uhlir wrote:
> On the other side mencoder complaints about libavformat and presence of B
> frames in source.
> http://lists.mplayerhq.hu/pipermail/mencoder-users/2007-January/004911.html
>
> [cite]
> ...If you wish to use libavformat muxing, you must ensure that your video 
> stream  does not contain B frames .. ... -lavfopts
> i_certify_that_my_video_stream_does_not_use_b_frames [/cite]

I believe that refers only to a problem with mencoder's integration of 
libavformat rather than the concept of B frames.

> What about GOP size? 12 (often used as Google suggests) or 15 (default
> Kdenlive). But it has not

kdenlive is following ffmpeg's lead here. ffmpeg's '-target dvd' option sets 
gop to 15 on PAL, which is the largest permitted by the specification. I do 
not know why 12 would be preferable--seems to me any argument would be loose.

> Any suggestions about ME size?

not from me

> Definitely I will try:
> deinterlance=1 and 0

it should be progressive=1, if it's even worthwhile attempting

> Where you get you knowledge of these advanced liavcodec/libavformat/ffmeg
> params? By studying code is there a comprehensive page/doc/man describing
> them?

There is the FFMPEG FAQ, mplayer manpage is quite helpful, and just 
experience. Also, a little study of various codecs by books and good web 
articles.