Image enhancement using inverse histogram based pixel mapping

摘要

This invention provides a method and associated device an inverse histogram based pixel mapping step is combined with an edge enhancement step such as unsharp masking. In such an arrangement the inverse histogram based pixel mapping step improves the performance of the unsharp masking step, serving to minimise the enhancement of noise components while desired signal components are sharpened. A second embodiment is described wherein the method of image enhancement comprises applying a histogram-based pixel mapping function to a set of image pixels prior to applying a highpass filter (HPF) in a loop of an edge enhancement unit that is parallel to an original image branch.