How can I cut a video into multiple parts and then join them together to make a new video with ffmpeg?
问题:
回答1:
You question is quiet general...
The following example may help you, but it might not solve your specific issues.
The example applies three stages:
Create synthetic video (with no audio):
ffmpeg -f lavfi -i testsrc=duration=3:size=160x120:rate=10 -c:v rawvideo -pix_fmt rgb24 testsrc.avi
(The created video is uncompressed).
Reference: https://trac.ffmpeg.org/wiki/FilteringGuideCut video into 3 parts (creating 3 video files):
ffmpeg -i testsrc.avi -ss 00:00:00 -c copy -t 00:00:01 sec0.avi ffmpeg -i testsrc.avi -ss 00:00:01 -c copy -t 00:00:01 sec1.avi ffmpeg -i testsrc.avi -ss 00:00:02 -c copy -t 00:00:01 sec2.avi
Reference: https://superuser.com/questions/138331/using-ffmpeg-to-cut-up-video
Concatenate (merge) 3 parts in reverse order:
ffmpeg -i "concat:sec2.avi|sec1.avi|sec0.avi" -codec copy output.avi
Note: for Linux use single quotes
'
Reference: Concatenate two mp4 files using ffmpeg
Synthetic video looks as the following image:
回答2:
You can use the concat demuxer.
#1 Create a text file
file video.mp4
inpoint 34.5
outpoint 55.1
file video.mp4
inpoint 111.0
outpoint 155.3
file video.mp4
inpoint 278
outpoint 316.4
The inpoint/outpoint directives specify the trim in and out points in seconds for the file listed above them.
#2a Create the joint file
ffmpeg -f concat -i list.txt combined.mp4
#2b Do the overlay together
ffmpeg -f concat -i list.txt -i background.mp4 -filter_complex "[0:v]scale=400:400[v1];[1:v][v1]overlay=0:0:shortest=1" -shortest -preset superfast "output.mp4"
External Audio stream with concat
ffmpeg -i 12m.mp4 -f concat -i list.txt -vf setpts=(PTS-STARTPTS)/1.1 -af atempo=1.1 -map 1:v -map 0:a -shortest new.mp4