Joint source-channel decoding of JPEG2000 images with unequal loss protection

This thesis proposes the joint decoding of JPEG2000 bitstreams and Reed-Solomon codes in the context of unequal loss protection. Using error resilience features of JPEG2000 bitstreams, the joint decoder helps to restore the erased symbols when the Reed-Solomon decoder fails to retrieve them on its own. The proposed joint decoding technique can deliver significant quality gain, though the process is often computationally exhaustive. To reduce the extra decoding time, we provide three solutions. The first two solutions employ smaller codeblocks and sub-coding-pass error localization to accelerate the process. Furthermore, we show how transmitting a relatively small amount of side information with high reliability may help the joint decoder by reducing the size of the search space and bypassing some of the JPEG2000 decoding iterations needed to verify the correctness of the restored source information. The improved joint decoder can perform significantly faster than the basic one.