how to compute pixel difference based upon gradient direction of an image

based on four different directions need to compute pixel difference satisfying threshold value

Answer 1

[Image Analyst]

I don't understand your question. But you might start with imgradient() or imgradientxy().

[Ram]

for image 256*256 calculated edge pixel and corresponding gradient direction such as 0,45,-45,-90 now for every edge pixel i need to calculate pixel difference based upon their corresponding direction and if the difference satisfy threshold value then need to store those pixel values. Please help in this regard