Hi all
I'm writing a simple GUI that should do this:

1.) take a folder with video files and transcode them to kdenlive friendly format.
q: what formats does Kdenlive prefer for hd and sd resolutions (speed (responsiveness) and likehood of crashing are important to me)

2.) open Kdenlive with project properties set (resolution, framerate) and clips added.
I guess the easiest way to do this is to create new project file and just open it.
q: how to create minimal project file? is there any documentation on this? any suggestions?
q: is there a different way of doing this?

3.) after some projects are finished editing, batch render them
I guess the best way to do this is pretty similar to Kdenlive-included rendering scripts.

Thanks for reading this, and thanks for trying to help me with this.

1.) There are no preferences, per se, just some things to avoid like Ogg Theora and AVCHD. We suggest transcoding the former to lossless Matroska and the latter to DNxHD. You should do some testing of your own.

2.) Generate MLT XML.
http://www.mltframework.org/twiki/bin/view/MLT/MltXml

3.) You can batch render using melt command line utility.
http://www.mltframework.org/twiki/bin/view/MLT/MltMelt

melt -profile something project.kdenlive -consumer avformat:out.foo ...

You will need to supply the correct -profile. See /usr/share/mlt/profiles for a list of profiles that match what is available in Kdenlive.
Then, you need to supply the -consumer avformat options in name=value syntax.

http://www.mltframework.org/twiki/bin/view/MLT/ConsumerAvformat

@gimzo
try my script just finished yesterday :S

http://kde-apps.org/content/show.php/akm-video-qt?content=134476

BTW my experience is that mjpeg and pcm in avi (yeah, avi sucks, but mjpeg isn't supported in any other container afaik) do the job really well. The main advantage is that this format is intraframe-only, and if you transcode it using ffmpeg and the -vsync 1 flag, there will be no skew between audio and video i.o.w. they can be demultiplexed without nasty surprises.

Having expressed my feelings towards avi a few minutes ago ;-) I saw the comment from Dan on DNxHD. Wikipedia tells me this format is supported by ffmpeg (and apparently by kdenlive as well), so I am surely going to try it out! MXF seems to be supported by ffmpeg, is it also supported by kdenlive or should I use the mov (mp4?) container?

MXF - well at least some of them - works in Kdenlive. I have some MPEG-2 MXF, but I do not believe ffmpeg supports muxing DNxHD in MXF. I just tried it, and it failed. MOV works.