How to get the image pixel at real locations in opencv?

Question

I want to retrieve the rgb of a pixel in the image. But the location is not integer location but real values (x,y). I want a bilinear interpolated value. How could

Answer 1

Using mapping can be more efficient if you want to do this repeatedly or consistently. ANother advantage is choosing an interpolation method and how to handle border conditions. Finally some of the interpolation functions are also implemented on GPU. remap