Method of adaptively enhancing a digital image

摘要

The present invention relates to a method of adaptively enhancing a digital image based on image content. An accurate determination of image type permits implementation of an image enhancement technique that is matched to the image type. The method is advantageous when the image type of the received images can vary. In one embodiment the method distinguishes between line art images and continuous tone images. The method includes application of a window to a pixels in a source array. The number of colors in each of the resulting windowed arrays is determined. Each color can optionally be defined as a range of colors. A color range total is calculated from the sum of the number of windowed arrays in one or more subsets of the plurality of possible numbers of colors. Image type is determined in response to the color range total and an enhancement process matched to the image type is applied to the digital image data.