Fuzzy screenshot comparison with Selenium

Question

I\'m using Selenium to automate webpage functional testing. It\'s important for us to do a pixel-by-pixel comparison when we roll out new code, so we\'re using Selenium to take

Answer 1

I've been using perceptualdiff which uses a model of the human visual system to try to avoid reporting unnoticeable changes (the authors used for renderer regression testing). Usage is quite simple:

perceptualdiff -output diff.ppm baseline.png test.png

(where diff.ppm is a PPM format image highlighting the areas of difference)

The needle regression testing framework has support for using pdiff to compare screenshots:

http://needle.readthedocs.org/en/latest/#engines