Watermarking problem - color to gray

Hello, How can watermark a color image inside a gray scale image? Thanks

Answer 1

[Walter Roberson]

Convert the grayscale image to its RGB equivalent, and then you can put a color watermark inside of it.

[Dani D]

Thank you,but i think after your solution,grayscale image will be colorful.

[Walter Roberson]

Yes, that is what you asked to have happen. When you watermark one image inside another, the purpose is to have the watermarking image show through (barely).

If you are trying to hide a color image inside a grayscale image, then you need steganography, not watermarking.