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I have several videos that are filmed with a portable camera and saved in .MOV. Since these are videos of university lectures and have video of the boardwork done by the professor, I would like to maintain the resolution available in the original (to make it possible to read the writing). However, Since it really is just a person talking in front of a black-board there is no reason to maintain the full 30 FPS for fluid motion. It would be acceptable to me to decrease the frame rate to 10 or even lower (sort of like a slide show) as long as the image quality is uncompromised.

I'm sure that ffmpeg is capable of doing this, and I know how to convert to .avi, but I'm not sure how to go about this whole down-rate thing.

Ideally these would be postable on youtube (do they understand videos with low frame-rates?), but even if it isn't possible having something I can distribute to the rest of the class that isn't 5 GB would be wonderful.

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Youtube is going to reencode your video to 25 fps anyway, so I would focus on the file size instead.

 ffmpeg -i -c:v libx264 -vprofile main -vf scale=-1:480 -c:a libvo_aacenc -ac 2 -ar 44100 out.flv

This will make
FLV container
H.264 video
Main Profile
480p resolution
AAC audio
2 channels (stereo)
44100 Hz sampling rate
128 kbit/s audio bitrate (assumed)

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