LCD Optimized Image Enhancement

Sammanfattning: With the increased bandwidth in 3G terminals, the possibilities to make new exciting multimedia applications are enormous. Mobile devices generally uses small LCD:s with only a few gray-scales or colors. The goal for this master thesis will be to find ways to enhance and correct the images before they are shown on the LCD. Could this be done with algorithms who enhance the images automatically depending on which information the images have? It will also be necessary to consider the LCDs characteristic before enhancement of the images. In this master thesis work it was discovered that sharpened and enhanced images with histogram modifications clearly improves the quality when displayed on the LCD. But it is also important to enhance the colors in the image, not only with color correction but also with dithering and quantization technique. Combining techniques like sharpening, color saturation and histogram modification gave clearly an improvement to the quality of the image and the result from the survey also pointed in this direction, the survey is published in appendix A. Some of the algorithms in histogram modification were used in an automatic enhancement and one of the algorithms worked with satisfaction. This histogram modification algorithm has been the basis for a patent application and we suggest a new outstanding performance histogram-modification method. The method cannot be described in this master thesis because the patent process is not finished.