pngcheck verifies the integrity of PNG, JNG and MNG files (by checking the internal 32-bit CRCs and decompressing the image data); it can optionally dump almost all of the chunk-level information in the image in human-readable form. For example, it can be used to print the basic statistics about an image (dimensions, bit depth, etc.); to list the color and transparency info in its palette (assuming it has one); or to extract the embedded text annotations. This is a command-line program with batch capabilities.
pngcheck verifies the integrity of PNG, JNG and MNG files (by checking the internal 32-bit CRCs and decompressing the image data); it can optionally dump almost all of the chunk-level information in the image in human-readable form. For example, it can be used to print the basic statistics about an image (dimensions, bit depth, etc.); to list the color and transparency info in its palette (assuming it has one); or to extract the embedded text annotations. This is a command-line program with batch capabilities.
To install pngcheck, run the following command in macOS terminal (Applications->Utilities->Terminal)
sudo port install pngcheck
To see what files were installed by pngcheck, run:
port contents pngcheck
To later upgrade pngcheck, run:
sudo port selfupdate && sudo port upgrade pngcheck
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