Efficient multi-scale retinex algorithm using multi-rate image processing

This paper describes an efficient image enhancement method based on the multi-scale retinex (MSR) theory for applying to a motion picture pre-processing. The proposed method uses a multi-rate x-y separable Gaussian filter with a polyphase structure and conducts illumination domain MSR composition. Therefore, The processing amount is drastically reduced to 4-order less than that of original MSR. As enhancing dark and bright areas in an image is the main pre-processing purpose, the method modifies an enhancement function so as to improve color rendition of bright areas on an image. Although our approach aims at simple implementation, the proposed method shows similar performance to the original one and better performance than those of histogram equalization approaches.