This small Python program will make (n*m) copies of the image, then gradually remove two of the RGB color channels.
You can run the program through the Python IDE, and then follow the prompts. It will first ask for the filename you want to upload, then the number of rows and columns you want for the image, the two color channels you want to remove, and then it will ask you to provide a new filename with multiple copies of images.
I used NumPy and Matplotlib for performing image manipulation