ffmpeg complex filter - multiple crops on black background

Question

We are attempting to process a video file by cropping it into several pieces and arranging it on a black background which is exactly 1920x1080. The following command runs but it never completes and we have to kill the process.

Is there something wrong with how we're trying to do this?

ffmpeg -i in.mov -y -filter_complex "\
color=s=1920x1080:c=black[bg];\
[0:v]crop=w=1920:h=ih:x=0:y=0[crop1];\
[0:v]crop=w=iw-1920:h=ih:x=1920:y=0[crop2];\
[bg][crop1]overlay=x=0:y=0[out1];\
[out1][crop2]overlay=x=0:y=h[final]" \
-map [final] out.mov

score 1 · Accepted Answer · answered Oct 31 '17 at 19:02

1

The color base has no duration set, and so runs indefinitely. The overlay filter by default terminates when the longer input ends. Here, it doesn't. So, let's correct that.

ffmpeg -i in.mov -y -filter_complex "\
color=s=1920x1080:c=black[bg];\
[0:v]crop=w=1920:h=ih:x=0:y=0[crop1];\
[0:v]crop=w=iw-1920:h=ih:x=1920:y=0[crop2];\
[bg][crop1]overlay=x=0:y=0:shortest=1[out1];\
[out1][crop2]overlay=x=0:y=h[final]" \
-map [final] out.mov

answered Oct 31 '17 at 19:02

Gyan

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One other question, any idea why we're seeing such a loss in quality in the output file? – Kevin O'Hara Nov 07 '17 at 18:42
ffprobe says the input codec is qtrle and the output codec is h264 – Kevin O'Hara Nov 07 '17 at 19:15
Share the full console log. – Gyan Nov 08 '17 at 05:38

ffmpeg complex filter - multiple crops on black background

1 Answers1