R: 146 / I: 109
ITT: ways of extracting clips from videos and editing them.
Here's a screen capture showing how to use ffmpeg and Avidemux to cut and crop a clip from a video. I've sped the action up by a factor of 2 so it's easier to watch.
I start by using converting the video into a format I know Avidemux can read. This isn't always necessary (and, in fact, wasn't in this case), but I wanted to show it anyway. To avoid having to convert the whole video, I start by opening it and finding the approximate time of the clip I want.
Then I invoke ffmpeg at the command prompt to convert the video:
ffmpeg -ss 20:40 -i source.mp4 -t 20 -pix_fmt yuv420p -c:v ffvhuff -an tmp1.mkv
To break this down:> -ss 20:40
start at 20 minutes, 40 seconds> -i source.mp4
input file is source.mp4> -t 20
convert 20 seconds of video> -pix_fmt yuv420p
8-bit YUV color with 4:2:0 chroma subsampling, the same as what's used in the VP8 format which is what we want at the end> -c:v ffvhuff
Convert the video to the ffvhuff format. This is lossless format, meaning we don't lose quality by converting to it, but the files are very large.> -an
no audio> tmp1.mkv
the output file