A MS-GS VQ codebook design for wireless image communication using genetic algorithms

Abstract

An image compression technique is proposed that attempts to achieve both robustness to transmission bit errors common to wireless image communication, as well as sufficient visual quality of the reconstructed images, Error robustness is achieved by using biorthogonal wavelet subband image coding with multistage gain-shape vector quantization (MS-GS VQ) which uses three stages of signal decomposition in an attempt to reduce the effect of transmission bit errors by distributing image information among many blocks, Good visual quality of the reconstructed images is obtained by applying genetic algorithms (GA's) to codebook generation to produce reconstruction capabilities that are superior to the conventional techniques, The proposed decomposition scheme also supports the use of GA's because decomposition reduce the problem size, Some simulations for evaluating the performance of the proposed coding scheme on both transmission bit errors and distortions of the reconstructed images are performed. Simulation results show that the proposed MS-GS VQ with good codebooks designed by GA's provides not only better robustness to transmission bit errors but also higher peak signal-to-noise ratio even under high bit error rate conditions.