обрезать ffmpeg mp4 видео из консоли бесплатно

There are two ways how to split video files by ffmpeg. The first one is good in itself, more than that - it is faster, but sometimes creates output files with certain flaws. So for those cases there is the second way of splitting video files: it is considerably slower, the output files are bigger, but it seems they are always of the same quality level as input files used.
Way 1:

ffmpeg -ss <start> -i in1.avi -t <duration> -c copy out1.avi

Way 2:

ffmpeg -ss <start> -i in1.avi -t <duration> out1.avi

• <start> – the beginning of the part of a video ffmpeg is to cut out. Format: 00:00:00.0000, meaning hours:minutes:seconds:milliseconds.
• <duration> – the duration of the part of a video ffmpeg is to cut out. Same format as above.

Examples:

ffmpeg -ss 01:19:00 -i in1.avi -t 00:05:00 -c copy out1.avi
ffmpeg -ss 01:19:00 -i in1.avi -t 00:05:00 out1.avi

ffmpeg cuts out a part of the video file starting from 1 hour 19 minutes 0 seconds. The duration of the video sequence cut out is 5 minutes 0 seconds.

качаем:
http://ffmpeg.org/download.html

еще!!:
 http://trac.ffmpeg.org/wiki/Seeking

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