So with ver 0.9.10 the render parameters for kdenlive/melt have changed a bit.
For example this is the parameters for H.264/AAC (CBR)
properties=x264-medium vb=%bitrate+'k' pass=%passes ab=%audiobitrate+'k'

And the dialog where you can edit render parameters now has a link to melt doco on melt parameters http://www.mltframework.org/bin/view/ML ... erAvformat

The new thing in the parameters is the properties=<something> syntax. Where does this syntax come from. It is not documented on the melt ConsumerAvformat.

In the old days you would supply a video codec with vcodec=<something> eg vcodec=mpeg2video
and you would supply an audio codec acodec=<something> eg acodec=mp2

So what is with this new properties=x264-medium etc ? Is there doco ?

Here it is:
http://www.mltframework.org/bin/view/ML ... rtyPresets
(using files in /usr/share/mlt/presets/consumer/avformat/ for default install)
These are profiles already elaborated by MLT people, my idea was to avoid to duplicate the work (regarding evolutions and maintaining)...