Compare two images, and return the rate of similarity in % [duplicate]

This question already has answers here: Algorithm to compare two images in C# 开发者_开发百科 (6 answers) Closed 4 years ago.

In my project i have to compare two images, in any format(*.png, *.jpg, *.bmp etc.), and return the rate of similarity in percents.

Did anyone do this?

If yes, how?

---

If you are trying to compare an image (or part of it) with another images, I searched internet and found that leadtools has correlation functions that compare an image with all the areas of the same dimensions in another image. For more information, see this link: http://www.leadtools.com/help/leadtools/v175/dh/po/leadtools.imageprocessing.core~leadtools.imageprocessing.core.correlationcommand.html