Error resilient video compression and transmission

This thesis presents an error resilient video compression and transmission based on the three-dimensional set partitioning in hierarchical trees (3-D SPIHT) algorithm. Compressed video bitstreams require protection from channel errors in a wireless channel and protection from packet loss in a wired ATM channel. The three-dimensional (3-D) SPIHT coder has proved its efficiency and its real-time capability in compression of video. A forward-error-correcting (FEC) channel (RCPC) code combined with a single ARQ (automatic-repeat-request) proved to be an effective means for protecting the bitstream. There were two problems with this scheme: the noiseless reverse channel ARQ may not be feasible in practice; and, in the absence of channel coding and ARQ, the decoded sequence was hopelessly corrupted even for relatively clean channels. In this thesis, we eliminate the need for ARQ by making the 3-D SPIHT bitstream more robust and resistant to channel errors using several schemes, such as Spatio-Temporal Tree Preserving 3-D SPIHT (STTP-SPIHT), Unequal Error Protection 3-D SPIHT (UEP-SPIHT), and Error Resilient and error Concealment 3-D SPIHT (ERC-SPIHT). In the STTP-SPIHT, we first break the wavelet transform into a number of spatio-temporal tree blocks which can be encoded and decoded independently by the 3-D SPIHT algorithm. This procedure brings the added benefit of parallelization of the compression and decompression algorithms. In addition, we demonstrate that the STTP-SPIHT has the functionality of region based video encoding/decoding and spatial and/or temporal scalability. We demonstrate the packetization of the bit stream and the reorganization of these packets to achieve scalability in bit rate and/or resolution in addition to robustness. Then we encode each packet with a channel code. Not only does this protect the integrity of the packets in most cases, but it also allows detection of packet decoding failures, so that only the cleanly recovered packets are reconstructed. In extensive comparative tests, the reconstructed video is shown to be superior to that of MPEG-2, with the margin of superiority growing substantially as the channel becomes noisier. In the UEP-SPIHT, we demonstrate that the 3-D SPIHT can also be error resilient against channel bit errors by unequally protecting the embedded video bitstreams, and more error resilient when we protect the STTP-SPIHT bitstreams unequally. In the ERC-SPIHT, we use a different method for partitioning the wavelet coefficients into s-t blocks to get stronger error resilience. In addition to that, we apply a different tree structure to the ERC-SPIHT to get a better compression result. The bitstream partitioning methods produce parallelization, making possible real-time implementation in hardware and software.