Compare the difference of two Images.

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I chose PYTHON script. But the script has some problem. I need to change “import Image” to “From PIL import Image”.


The output will give the pixel difference in percentage.


But I don’t understand the output. A more clear way is got from In this method, the different pixel number will be output.

This used ImageMagick in Linux. The command to compare a.png and b.png is:

compare -metric ae a.png b.png null:

The output is the number of different pixel. If you want the percentage. You need to use the following command to get the X and Y for the image and use X*Y to calculate the total pixel. Then use the above result divided by the below result to get the percentage.

identify a.png


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