IMAGE ERROR CONCEALMENT BASED ON QIM DATA HIDING IN DUAL-TREE COMPLEX WAVELETS

摘要

Transmission of block-coded images through error-prone radio mobile channel often results in lost blocks. Error concealment (EC) techniques exploit inherent redundancy and reduce visual artifacts through post-processing at the decoder side. In this paper, we propose an efficient quantization index modulation (QIM)-based data hiding scheme using dual-tree complex wavelet transform (DTCWT) for the application of image error concealment. The goal is achieved by embedding important information (image digest) as watermark signal that is extracted from the original image itself and is used to introduce sufficient redundancy in the transmitted image. At the decoder side, the extracted image digest is used to correct the damaged regions. DTCWT offers three-fold advantages viz. (1) high embedding capacity due to inherent redundancy that leads to the better reconstruction of high volume missing data, (2) better imperceptibly after data embedding since it most closely captures human visual system (HVS) characteristics than conventional DWT and (3) better watermark decoding reliability. Simulation results duly support the claims and relative performance improvement with respect to the existing results.