Post-Processing for Restoring Edges and Removing Artifacts of Low Bit Rates Wavelet-Based Image <Abstract> Compression artifacts are the results of an aggressive data compression scheme applied to an image that discards some data which is determined by an algorithm to be of lesser importance to the overall contents but which is nonetheless discernible and objectionable to the user. In this paper we present a post-processing algorithm that focuses on restoring the clarity of important image features, such ad edges, and removing the compression ringing artifacts around edges at compression ratios of 100:1 and greater. At the decoder, the algorithm extracts the locations of edges from reconstructed image and classifies the pixels surrounding edges for removing compression ringing artifacts, then applies a linear procedure to restore the clarity of the edges. With this algorithm, edges in the images which important for recognition are well restored, and the compression ringing artifacts are removed at very low bit rates. |