ffmpeg - Correct aspect ratio without re-encoding video file - Super User

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ffmpeg - Correct aspect ratio without re-encoding video file - Super User

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Tags: video-encoding howto ffmpeg aspect-ratio mp4box superuser.com

Clipped on: 2024-06-30

$h - resolution height
x - aspect ratio width
y - aspect ratio height

Notes:

If you put -aspect x:y without -vf scale=$w:$h, the output will only have the change on display aspect ratio.
If you put -vf scale=$w:$h without -aspect x:y, the output will only have the change on the resolution.
The command -vf scale=$w:-1 or scale=-1:$h will not always provide the expected output so to make sure you get both change on resolution and aspect ratio, you can just use the above command line.

** I only tried this with input.mkv and output.mkv files since this is only what I am working on at the moment. Feel free to try this with the other file types.

Edit

edited May 27, 2021 at 6:34

MMM

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answered May 10, 2021 at 7:36

MrClay

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Unless I'm mistaken, this re-encodes the video.
– Sawtaytoes
Commented May 13, 2023 at 7:40

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ffmpeg 4.3.2 -bsf:v h264_metadata=sample_aspect_ratio=x/y gives an error on DNxHR coded Quicktime files while MP4Box writes a second line of PAR into the metadata.

Width : 720 pixels Height : 540 pixels Display aspect ratio : 16:9 Original display aspect ratio : 4:3

I tested multiple players and even an NLE and so far all display the correct aspect ratio.

Edit

answered Mar 25, 2021 at 17:07

Oliver Ohlendorf

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