Strange random artifact after resize (adaptive-resize) ignoring aspect ratio

[baarreth]

Hello. I would like some help/advice with a problem/bug I am facing.
I am upscaling some old cartoons, and to make it 1080p as smaller as possible, I am using "convert" to resize the images before running ffmpeg.
However, for every ~5000 images, I randomly get one wrong conversion.

Is there a way to verify the conversion (without taking twice the processing time)?

$ uname -a
Linux baarreth 5.15.0-130-generic #140~20.04.1-Ubuntu SMP Wed Dec 18 21:35:34 UTC 2024 x86_64 x86_64 x86_64 GNU/Linux

$ convert -version
Version: ImageMagick 6.9.10-23 Q16 x86_64 20190101 https://imagemagick.org
Copyright: © 1999-2019 ImageMagick Studio LLC
License: https://imagemagick.org/script/license.php
Features: Cipher DPC Modules OpenMP
Delegates (built-in): bzlib djvu fftw fontconfig freetype jbig jng jpeg lcms lqr ltdl lzma openexr pangocairo png tiff webp wmf x xml zlib

command:
convert "input image" -adaptive-resize 1408x1080! -verbose "output image"

input image

output image

output image after running the command again

[fmw42]

Be sure that your /tmp directory is not full, especially with Imagemagick temp files.

[baarreth]

Thank you for your advice.
I am resizing all files again to test about the /tmp directory, and I may be wrong, but I don't think imagemagick is using /tmp.
Could you give me another idea?

$ df -h

$ free -h

output of
for i in ${INUP}/*.jpg; do convert $i -adaptive-resize ${W1080}x1080\! -verbose ${OUTUP}/${i##*/}; done

(still running)

[fmw42]

Imagemagick uses /tmp to store temporary files while doing its processing. Or if you have sent the Imagemagick environment variable MAGICK_TEMPORARY_PATH to set path to store temporary files, they will be placed there.

The normally get automatically deleted, but if there is a sudden crash, they get left there.

See https://imagemagick.org/script/resources.php#environment

On Windows it is likely some_path_to/temp

[baarreth]

Thank you for your explanation.
I didn't change the environment variable, and when I looked inside /tmp, there were no imagemagick related file or folder there. So maybe this is not a crash issue, or the subsequent call of "convert" cleaned the files.
Anyway, after your advice, I realized I should be checking the returning value each time I call "convert"...

[snibgo]

You might try "-synchronize". See https://imagemagick.org/script/command-line-options.php#synchronize

[baarreth]

Thank you for the suggestion!
I am using "-synchronize" for the last 2 days, and I think it solved the problem.