How to change the colour of the backgroud

Hi, i rotate an image and i want to change the black background to white. Thanks in advance.

Answer 1

[Laurent]

It depends on what type of image you have, but let's say it is a 8-bit grayscale image. In that case you can do the following:

thisim(thisim==0)=255;

where thisim contains your image.

If you would like a more specific answer, please provide us your image.

[Ren]

Thank u,it works^^