pnmpsnr

Compute the difference between two images. More information: https://netpbm.sourceforge.net/doc/pnmpsnr.html.

Compute the difference, i.e. the peak signal-to-noise ratio (PSNR) between two images:

pnmpsnr {{path/to/file1.pnm}} {{path/to/file2.pnm}}

Compare the color components rather than the luminance and chrominance components of the images:

pnmpsnr {{path/to/file1.pnm}} {{path/to/file2.pnm}} -rgb

Run in comparison mode, i.e. only output nomatch or match depending on whether the computing PSNR exceeds n or not:

pnmpsnr {{path/to/file1.pnm}} {{path/to/file2.pnm}} -target {{n}}

Run in comparison mode and compare the individual image components, i.e. Y, Cb, and Cr, to the corresponding thresholds:

pnmpsnr {{path/to/file1.pnm}} {{path/to/file2.pnm}} -target1 {{threshold_Y}} -target2 {{threshold_Cb}} -target3 {{threshold_Cr}}

Run in comparison mode and compare the individual image components, i.e. red, green, and blue to the corresponding thresholds:

pnmpsnr {{path/to/file1.pnm}} {{path/to/file2.pnm}} -rgb -target1 {{threshold_red}} -target2 {{threshold_green}} -target3 {{threshold_blue}}

pnmpsnr {{path/to/file1.pnm}} {{path/to/file2.pnm}} -machine