通过 md5 比较图像是如何工作的?

Does this method compare the pixel values of the images? I'm guessing it won't work because they are different sizes from each other but what if they are identical, but in different formats? For example, I took a screenshot and saved as a .jpg and another and saved as a .gif.

解决方案

An MD5 hash is of the actual binary data, so different formats will have completely different binary data.

so for MD5 hashes to match, they must be identical files. (There are exceptions in fringe cases.)

This is actually one way forensic law enforcement finds data it deems as contraband. (in reference to images)