Resolution enhancement of colored images by inverse diffusion processes

Algorithms for resolution enhancement are needed in various applications of image processing and communication such as compression, and HDTV. We develop a geometrical algorithm, based on diffusion processes which are used both for smoothing of colored images and enhancement of the colored images. The latter is accomplished by "solving" an inverse diffusion problem which is ill-posed. In order to stabilize the flow, as well as to enhance important features (e.g. edges) at the expense of less important image domains, we use a modified Beltrami diffusion equation. Results indicate that it is possible to impose the backwards flow, in spite of the instabilities, and thereby enhance the image up to a certain level of resolution which depends on the nature of the image.