Pre-Processing for MRC Layers of Scanned Images

Abstract

The mixed raster content (MRC) imaging model represents compound images as a superposition of layers. The model is very efficient for representing sharp text and graphics onto a background, but, since the mask layer is binary, it is difficult to deal with scanned data and soft edges. The edge transitions don't fully belong to the foreground neither to the background, and cause some "halo" to the object edges using the MRC model. We present a method to detect segmented soft edges and a method to correct and sharpen the image within the MRC model. An improved data filling algorithm for the redundant regions is also presented. The original "softness" and relative position of the edges are estimated and we present a method to attempt to recreate the edge softness effect at the decoder.