divide an image to blocks

hi i have an 256*256 image and i want to divide it to 8*8 blocks without overlapping and then calculate DCT for each blocks. how to do it?please help me

[Geoff Hayes]

Nadia - if you have the Image Processing Toolbox, you should check the example from here DCT with blockproc.

Answer 1

[Image Analyst]

There are code samples in the FAQ using two different methods, mat2cell() and regular indexing. That just gives you the subimages. You can call a function on them if you want to process each subimage. If you want to use blockproc(), see my attached demos.