Dear Hamed abdulaziz & Prabhakar
Thank you for your inquiries. I work mainly in signal feature extraction, rather than image feature extraction. My Suggestions for you could be:
1- Reshape each image into vector and apply this code on each vector.
2- OR, use the 2D wavelet decomposition commands (more suitable for images) and extract your features from each node in the same way am doing here. Note with the 2D version, you will have a small image at each node and you can use something like moment invariants to get the features from each image. Look here (http://www.mathworks.com.au/matlabcentral/fileexchange/33975-the-seven-invariant-moments)