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I have a heterogenous set of videos (codecs, dimensions, size) that I would like to crop off the top using ffmpeg. I've used this code successfully for year without any trouble (example here crops off 64px):

ffmpeg -i in.avi -y -pix_fmt yuv420p -an -qscale 1 -vcodec libx264 -vf crop=in_w:in_h-64:0:64 out.mp4

However, I've now run into a case that it does not work correctly, and I suspect it has something to do with SAR and DAR. I have a clip that shows pixel dimensions of 960x720 [SAR 960:720 DAR 16:9], original looks close to this:

original

When I use the above command, I end up with a video that ffprobe/ffmpeg says is 960x656 [SAR 4:3 DAR 80:41], but when I view it on a web browser or quicktime it is displayed as 1280x656:

output

How can I modify the command to account for this use case, without breaking the cropping of all other clips? Here's what I've unsuccessfully tried:

ffmpeg -i in.avi -y -pix_fmt yuv420p -an -qscale 1 -vcodec libx264 -vf scale=960:656,setsar=1 -vf crop=in_w:in_h-64:0:64 out.mp4
ffmpeg -i in.avi -y -pix_fmt yuv420p -an -qscale 1 -vcodec libx264 -vf setsar=sar=0 -vf setdar=dar=0 -vf crop=in_w:in_h-64:0:64 out.mp4
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  • Here's an archive of the input and output files I'm getting. ultrasoundoftheweek.com/give/uploads/clips.zip
    – user255406
    Oct 10, 2015 at 17:24
  • "Keep in mind that the sample aspect ratio set by the setsar filter may be changed by later filters in the filterchain, e.g. if another "setsar" or a "setdar" filter is applied." - so the correct order is needed and as said by @orgoro possibly try to do not separate filters and instead do: -vf "filter1=...,filter2=...,filter3"
    – 16851556
    Jun 15, 2021 at 21:18

2 Answers 2

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This should work universally.

ffmpeg -i in.avi -y -pix_fmt yuv420p -an -qscale 1 -vcodec libx264 -vf setsar=1,crop=in_w:in_h-64:0:64 out.mp4
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  • 2
    @user255406 libx264 ignores -qscale. Use -crf instead.
    – llogan
    Oct 10, 2015 at 20:23
  • It looks like in some cases you can simply use setsar= or even just setsar
    – Zombo
    Nov 27, 2017 at 2:43
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ffmpeg accepts only one video filter (marked as -vf) you should merge all the video filters you want into one, comma separated string:

ffmpeg ... -vf setsar=1,crop=in_w:in_h-64:0:64 out.mp4

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