How can I multiply matrix of vectors by matrix?
Show older comments
I have an RGB image, which is [width, height, 3] array. How can I multiply every pixel ([R, G, B] vector) by matrix (this is conversion RGB -> YIQ, but without rgb2ntsc function)? Also, it should be done without any loops.
Answers (1)
Not without loops, but hiding them inside bsxfun...
M = rand(140,160,3); % image data
T = randn(3); % transformation matrix, [y; i; q] = T*[r; g; b]
TM = cat(3, sum( bsxfun(@times, M, reshape(T(1,:), 1, 1, [])), 3), ...
sum( bsxfun(@times, M, reshape(T(2,:), 1, 1, [])), 3), ...
sum( bsxfun(@times, M, reshape(T(3,:), 1, 1, [])), 3));
Categories
Find more on Resizing and Reshaping Matrices in Help Center and File Exchange
Products
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!