Estimating Tri-Stimulus RGB values for digital camera

It is necessary to have complete tri-stimulus RGB values of each pixel because for digital camera many image processing pipeline were proposed each of them adopt different sequence of processing pipeline stages. In each of these stage different alogorithms for estimating tri-stimulus RGB value is used. In this paper we are reviewing algorithms for Auto-level Streching, White balance, Color interpolation that will be helpful in enhancing final image picture quality.