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I was advised to encode my HD files with ffmpeg to DNxHD proxy with 220M bitrate rather then 45M so the image doesnt have too much artifacts. I reduced the framerate to 29.97 fps when I encoded the clips and the project is also 29.97 fps.

The minute I apply an effect to my video track, playback is choppy in the compositor window (Cinelerra-CV) and I need to evaluate the clip with effects and see the motion in real-time. My computer is 4 core AMD 3.4 GHz with 12G memory. Ubuntu LTS 10.04.4 with desktop effects OFF. Decent Sata2 drives.

I don't want to re-encode my original clips at this point, so instead I was stuck rendering parts of the project to mpeg4 since it seems faster so I can add a couple of more effects. But some other clips that didnt need anymore effects were rendered to RGBa uncompressed to preserve quality. Now I dont know what to encode my final project to!! Its a potential mess! Anyone has an idea how to proceed?

And for the future, what the heck should I be encoding to next time?? (for Cinelerra). I'm having a hard time finding help in IRC etc, I hope there is a happy ending!

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ok here is more info. that could be useful: I am using ffmpeg 4.05.1-1 ubuntu 10.04 repo. –  Tara May 21 '12 at 17:09
the "recipe" I used was: code ffmpeg -i input.MTS -b 220M -s 1920x1080 -r 29.97 -vcodec dnxhd -an output.mov code _ sample clip properties are: quicktime for linux ac3 44100 16bit DNXHD 29.97 1920X1080 2 min36s=4.0G If someone could also confirm wether proxy files are meant to be furthur rendered or not before the final render... –  Tara May 21 '12 at 17:19
Tara, welcome, please provide the ffmpeg output and the command you typed, this way we can know all about the input and the output files. –  E.G. Jun 15 '12 at 5:09

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