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Shrink PNG images lossily with pngquant

destructiveImages and performancedebian, ubuntu
Adjust the values, the command updates live
user@server
find /var/www/vhosts/example.com/httpdocs/wp-content/uploads -type f -iname '*.png' -exec pngquant --quality=65-85 --skip-if-larger --strip --force --ext .png {} +

Converts PNGs to 8-bit palette images with transparency and writes the result over the original (--ext .png --force). If the minimum quality is not reached or the new file is larger, the original stays untouched. Usually barely visible for graphics, icons and screenshots, for photos WebP is the better choice.

Note: Lossy and irreversible, make a backup first. Install the pngquant package if needed. Skipped files cause a non-zero exit code, which is not an error.

Also searched as

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  • reduce png file size by half
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  • shrink large png graphics

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Optimize PNG images losslessly with optipng

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Convert images to AVIF recursively

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Convert images to WebP recursively

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Find images larger than a given pixel size

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Find images without a loading attribute on a page

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