Low rank approximation of grayscale image based on SVD
Eckhart, University of Chicago

See svd_eckhart_a.m and svd_eckhart_b.m for the detail.

Original RGB Image Original Image and Approximations
Original Grayscale Image A=A(480)
480 by 640 matrix, rank(A)=480
A(20): the best approximation by matirices of rank 20
A(50): the best approximation by matirices of rank 50 A(80): the best approximation by matirices of rank 80