an image processing system that performs edge - enhancement on an image . the image processing system processes a region of the image at a given time . one specific pixel of an image region is compared to several surrounding pixels to determine the existence of a black edge or a white edge in the image . additionally , the image processing system includes a classifier that determines whether the image is substantially text - like or substantially photo - like . when the image is substantially text - like , a dynamic black threshold is used to determine the existence of a black edge within the image . the dynamic black threshold is modified during the processing of the image by the image processing system as a function of the relationship between the one specific pixel to at least one other of the several surrounding pixels . the image processing system selectively applies a first threshold scheme or a second threshold scheme upon identification to the image depending on the characteristics of the one specific pixel . using the image processing system as described herein , high frequency content , namely the sharpness of the image , is preserved while low frequency content within the image is maintained smooth thereby providing a high visually perceptually quality of the image after having performed image processing . the present invention provides a novel manner of performing edge enhancement using a dynamic threshold in certain instances and a fixed threshold in others .