A good site for learning basics of IP.

http://www.imageprocessingbasics.com/

Steve (Co-author of Gonzales) on Matlab Image processing basics!

http://blogs.mathworks.com/steve/2011/09/27/digital-image-processing-using-matlab-reading-image-files/

Image Processing and Software Epistemology

http://lab.softwarestudies.com/2012/11/image-processing-and-software.html