Check a directory of PNG files for errors

ls *.png |parallel --nice 19 --bar --will-cite "pngcheck -q {}"
Useful for checking if a large number of PNG files was downloaded successfully by verifying the built-in CRC checksum. For incomplete files, the command will print: "00002309.png EOF while reading IDAT data ERROR: 00002309.png" The process is very fast; checking 21,000 files of 5MB in size took only five minutes on a 2011 Intel mobile dual-core.

1
By: Negate
2021-09-05 00:37:07
ls parallel png
1
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What Others Think

Don't parse `ls` output ! Besides, `parallel` can be given the same you gave `ls`, so piping `ls` in `parallel` is 100% redundant.
rautamiekka · 227 weeks and 5 days ago

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