Abstract
In this paper, we proposed a multiple description distributed image coding system for mobile wireless transmission. The innovations of proposed system are two folds: First, when MDC is applied to wavelet subband based image coding; it is possible to introduce correlation between the descriptions in each subband. At the encoder, the correlation information is encoded by systematic Reed Solomon (RS) encoder. Only the parity check bits are sent to channel. At the receiver, when part of descriptions are lost, however, their correlation information are available, the Wyner Ziv decoder can still recover the description by using the correlation information and the partly received description as noisy version and the side information. Secondly, in each description, we use multiple bitstream image coding to achieve error robust transmission. In conventional entropy subband coding, the first bit error may cause the decoder to discard all subsequent bits. A multiple bitstream image encoding is developed based on the decomposition of images in the wavelet domain. We show that such decomposition is able to reduce error propagation in transmission, thus to achieve scalability on PSNR performance over the changes of BER, Experimental result shows that the PSNR could be improved with the same coding rate.
