How to correct RGB color taken with camera ?

Question

Hi everyone,
I had this question in my mind lately: I have taken a photo of a picture in my computer's display using my phone's camera (2MP) then transferred the picture to my computer. What i have noticed is that the individual pixel (RGB) values of the photographed image are different from the original picture (which is obvious !) but the color looks the same; so what i intend to do is modify the photographed image so that the pixel color values (RGB) are the same as the original (100% if possible), in other words make every pixel identical to the original picture ! without making use of the original picture.

I do not know if this is possible or not but any help will be extremely appreciated, I'm using Visual c++ 2005 with CIMG Library for processing images !

Thanks in advance !

Answer 1

I'm more interested in WHY you photograph your own screen? If you are running windows you can just press the "Print Screen" key on your keyboard and then open, for example Paint and paste the image.

The colour difference is there because you have not white balanced your camera. Even the most mobile phone cameras can white balance. Take a picture filled entirely with white on your screen. Then tell the camera to use it as a reference for white. Take your photo and it should be correct.