how to divide an image into overlapping blocks using DCT

I have 512x512 pixels image and i want to divide the image into overlapping blocks and after that i want to extract features in order to perform the image forgery detection.

Answer 1

[Image Analyst]

See the FAQ for how to get NON-overlapping blocks. http://matlab.wikia.com/wiki/FAQ#How_do_I_split_an_image_into_non-overlapping_blocks.3F Note: DCT is not used nor needed to specify a block/tile/subimage of a larger image. You can make changes to blockproc() if you want the blocks to overlap instead of move in "jumps" of the window size. Or you can use conv2(), imfilter(), or nlfilter() if you want the block to slide over only one pixel at a time regardless of what the block width is.