image.type() function in opencv returns some value, how do we know what type that value represents?

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I have different types of images (8 bit 1 channel, 16 bit 1 channel etc). To determine the type of the image, i am using the Mat::type() function.

for some images it returns 2, for some it returns 16 etc etc. What type does this 2 and 16 represents.

If I can get a list of these image types, it would be the best. Thanks