Statistics for partial image using AForge.NET?

[Forino]

I need to get statistics info (for example, standard deviation) for center area of an image. Can someone tell me how to achieve this? Thank you.

[andrew.kirillov]

There is a class in AForge.NET framework to get statistics about an image (check docs). Apply it to the "center" of your image, whatever you mean by it (extract it the way you like).

[Forino]

The center of the image is in eclipse shape, only the pixels inside the eclipse should count for the standard deviation.

Would you mind to explain a bit more on "Apply it to the "center" of your image"? Does this function accept some kind of filter as a shape?

Or does it mean that I need to make a new image using the center part with a transparent background. I assume that the library will recognize the transparent part and ignore the transparent pixels during the calculation?

Thanks!