An Adaptive Mobile Multi-media Communicator

The complexity, robustness, image quality as well as bit rate and power consumption issues of adaptive multi-media communicators are addressed. The proposed robust, moderate complexity motion-compensated Discrete Cosine Transform (DCT) based image communicator provides an image peak signal-to-noise ratio (PSNR) of 38 dB at an average bit rate of about 25 kbitsls. Bandwidth efficient adaptive 16 or 64-level quadrature amplitude modulation (QAM) combined with embedded low-complexity binary Bose-Chaudhuri-Hocquenghem (BCH) forward error correction (FEC) coding is deployed. Our proposed 65-10 kBd adaptive multimedia communicator adjusts the number of modulation levels,'the image and FEC codec parameters as well as other system algorithms in order to meet time-varying optimisation criteria. The DCT/BCH/l6-QAM and DCTIBCHI64-QAM schemes provide nearly unimpaired image quality for channel SNRs in excess of 30 dB and 40 dB, respectively.