How to replace color of an image?

Question

I want to replace color of an image. For example turn all blue colors to red without any distortion on shape. When i try this i can swap the colors by iterating every pixel,

Answer 1

I'm not fully understand the question. But from the example given, i see that the process of changing blue into red was fail. instead of becoming red, it becomes gray. does color gray is what you mean by flat?

If that so, it looks like color channel error. to change blue to red, we have to change (0,255,0) to (255,0,0).

I'm not sure if it is the problem, maybe code snippet could help for evaluation. to make sure what is the real problem.

Answer 2

The problem with the issue that you are asking is that a strict color replacement will modify the shape of the image. What you need to do is get a little information on what the shape is. I.e. Find boundaries and shading along the boundaries. My suggestion to you is:

1. Use edge detection to separate out blobs
2. Find a blob that fits your demands: i.e. Has a tolerant likelihood for [color]ish.
3. Identify blobs and filters applied
4. Recolor the blob and reshade.

IMO: That is the only way you're going to get the result you're looking for.

Some notes: Finding a blob may require some testing to determine how much tolerance you have for blobs and shapes. [Connected Regions].

Another thing: The shading and relative coloring will require you to have a devience for the color you want.

Answer 3

The usual way to do this is to use an RGBImageFilter. See the docs for FilteredImageSource for how to use such a filter.