Image Enhancement by Fusion in Contourlet Transform

Most existing image enhancement algorithms work on a single image. Their
performance is limited to the capacity of the sensor by which the image is taken. In some cases
they completely fail to provide us the necessary enhancements. This paper proposes a
composite image approach for enhancing still images. The approach proposed combines the
relevant features of the input images and produce a composite image which is rich in
information content for human eye. The input images are first decomposed into multiple
resolutions by using the contourlet transform which provides a better representation than the
conventional transforms. Transformed coefficients are combined with a predefined fusion rules. The resultant image is found by performing inverse contourlet transformation of the composite image. The results found are encouraging and the algorithm does not introduce any distortion for applications in low light and/or non uniform lighting conditions. The composite image also contains almost all of the salient features of the input images.