GIMP :: How To Extract RGB Pixel Data From JPG

I am trying to take a jpg file of an image, and write each RGB pixel color's value into a 3 component integer vector corresponding to the RGB components of the color for that pixel. For each pixel in the jpg, I wish to write the corresponding 3 by 1 integer vector into a matrix after which I plan to do a SVD decomposition of the newly constructed matrix to do an image analysis.

Any plug-in that allows one to efficiently iterate through each pixel in a jpg, and convert the pixel data to a RGB integer vector, and say write to a file?

Specific Details: I am using gimp 2.6 as my image editor, and wish to collect all the RGB 3 by 1 integer vectors (where each 3 by 1 integer vector corresponds to RGB color of exactly one pixel in the jpg image) into a matrix of integer so that I can do a reduced SVD decomposition of that matrix to analyse the pixel data: I wish to compare two similar images by using the SVD decomposition of integer matrices corresponding to the two images saved as jpg files pic1.jpg and pic2.jpg.