[FEATURE] Compare image with Structural Similarity Index (SSIM)

[huemach78]

Hi Roman

Thank you for providing the comparison tool. It's useful for our work.
besides that, Could you consider adding more comparison methods like SSIM (Structural Similarity Index)?

Reference
https://pyimagesearch.com/2017/06/19/image-difference-with-opencv-and-python/

https://stackoverflow.com/questions/71567315/how-to-get-the-ssim-comparison-score-between-two-images

https://github.com/americanexpress/jest-image-snapshot

https://www.google.com/amp/s/discuss.dizzycoding.com/detect-and-visualize-differences-between-two-images-with-opencv-python/%3famp=1