Grouping similar pixels in bins

Hi,

Can someone tell me how do I divide the pixels in an image into let's say 16 bins? For example we have a grayscale image [0-255], I want all the pixels between 0-15 to be let's say in group 1, 16-31 in group 2 and so on. Importantly, I want to have the location of the pixels in each group like I should know let's say what is the location of pixels in i-th group. I can write a for loop but I need to know if there's a function that does that.

Thanks in advance.

Answer 1

[Guillaume]

Use imquantize:

binnedimage = imquantize(grayimage, 15:16:255) %16 bins of size 16.

You can then use find to get the location in each group:

binpixels = arrayfun(@(val) find(binnedimage == val), 1:16, 'UniformOutput', false) %using linear indices

[Muzammil Behzad]

Thanks a lot!