<title>Enhancement of color image data captured using single chip CCD arrays</title>

Abstract

Charge coupled devices (CCDs) are commonly used in image capture devices to measure color information. A common inexpensive imaging device will use a single chip CCD array. Each CCD element is coupled with a filter for measuring the red, green or blue color content at a particular point. Ideally it is desirable to obtain full RGB color information for each point, however this is not possible as elements with different spectral filters can not occupy the same spatial location. As a result of this, color edges may appear at different spatial locations in the individual color planes causing artifacts such as blurry edges and false coloring. This paper proposes an algorithm for enhancing color image data which was captured with typical single chip CCD arrays. The algorithm is based on stochastic regularization using a Gaussian image model with a deterministic line process to realign the edge information. This image model is used in a maximum a posteriori estimation technique, resulting in a constrained convex optimization problem. Computationally this is optimized using an iterative constrained gradient descent algorithm. Results show that the algorithm works well to reduce, and often eliminate, the visible artifacts in this type of color image capture device.