Andrey Norkin

Schemes for multiple description coding of stereoscopic video

This paper presents and compares two multiple description schemes for coding of stereoscopic video, which are based on H.264. The SS-MDC scheme exploits spatial scaling of one view. In case of one channel failure, SS-MDC can reconstruct the stereoscopic video with one view low-pass filtered. SS-MDC can achieve low redundancy (less than 10%) for video sequences with lower inter-view correlation. MS-MDC method is based on multi-state coding and is beneficial for video sequences with higher inter-view correlation. The encoder can switch between these two methods depending on the characteristics of video.

Two-stage multiple description image coders: Analysis and comparative study

A general two-stage multiple description coding (MDC) scheme using whitening transform is analyzed. It represents the original image in a form of a coarse image approximation and a residual image. The coarse approximation is subsequently duplicated and combined with the residual image further split into two descriptions using a checkerboard block transform coefficients rearrangement. We identify the importance of a good coarse approximation and explore different approaches for changing its resolution and coding it. We also propose different approaches for coding the residual signal. The coder scheme is quite simple and yet achieves high performance comparable with other MDC methods.

Wavelet-based multiple description coding of 3-D geometry

In this work, we present a multiple description coding (MDC) scheme for reliable transmission of compressed three dimensional (3-D) meshes. It trades off reconstruction quality for error resilience to provide the best expected reconstruction of 3-D mesh at the decoder side. The proposed scheme is based on multiresolution geometry compression achieved by using wavelet transform and modified SPIHT algorithm. The trees of wavelet coefficients are divided into sets. Each description contains the coarsest level mesh and a number of tree sets coded with different rates. The original 3-D geometry can be reconstructed with acceptable quality from any received description. More descriptions provide better reconstruction quality. The proposed algorithm provides flexible number of descriptions and is optimized for varying packet loss rates (PLR) and channel bandwidth.

Packet Loss Resilient Transmission of 3D Models

This paper presents an efficient joint source-channel coding scheme based on forward error correction (FEC) for three dimensional (3D) models. The system employs a wavelet based zero-tree 3D mesh coder based on progressive geometry compression (PGC). Reed-Solomon (RS) codes are applied to the embedded output bitstream to add resiliency to packet losses. Two-state Markovian channel model is employed to model packet losses. The proposed method applies approximately optimal and unequal FEC across packets. Therefore the scheme is scalable to varying network bandwidth and packet loss rates (PLR). In addition, distortion-rate (D-R) curve is modeled to decrease the computational complexity. Experimental results show that the proposed method achieves considerably better expected quality compared to previous packet-loss resilient schemes.

Multiple Description Coding of 3D Geometrywith Forward Error Correction Codes

This work presents a multiple description coding (MDC) scheme for compressed three dimensional (3D) meshes based on forward error correction (FEC). It allows flexible allocation of coding redundancy for reliable transmission over error-prone channels. The proposed scheme is based on progressive geometry compression, which is performed by using wavelet transform and modified SPIHT algorithm. The proposed algorithm is optimized for varying packet loss rates (PLR) and channel bandwidth. Modeling distortion-rate function considerably decreases computational complexity of bit allocation.

Low-complexity multiple description coding of video based on 3D block transforms

The paper presents a multiple description (MD) video coder based on three-dimensional (3D) transforms. Two balanced descriptions are created from a video sequence. In the encoder, video sequence is represented in a form of coarse sequence approximation (shaper) included in both descriptions and residual sequence (details) which is split between two descriptions. The shaper is obtained by block-wise pruned 3D-DCT. The residual sequence is coded by 3D-DCT or hybrid, LOT+DCT, 3D-transform. The coding scheme is targeted to mobile devices. It has low computational complexity and improved robustness of transmission over unreliable networks. The coder is able to work at very low redundancies. The coding scheme is simple, yet it outperforms some MD coders based on motion-compensated prediction, especially in the low-redundancy region. The margin is up to 3 dB for reconstruction from one description.

Principal Component Analysis in Multiple Description Coding of Spectral Images

Communications in general require protection due to error-prone channels. In geoscience and remote sensing, especially coded or compressed data, and results from classifications are vulnerable to transmissions errors. Multiple descriptions of data are one way for protection of communications over unreliable channels. This study concentrates on multiple description of spectral images as a way for providing scalable coding. The principal component analysis outputs the common content, the redundant part, for the two descriptions and then the integer wavelet transform selects different contents for those descriptions. In the experiments, the goal was to find good parameterization in the transmitter for generating the two descriptions which will allow perfect reconstruction if both of them are available at the receiver. The reconstruction quality for various number of principal components is demonstrated. Integer wavelet filter 5/3 showed the best performance among the implemented filters.

Multiple Description Coding of 3D Meshes Based on Forward Error Correction

This work presents a multiple description coding (MDC) scheme for compressed three dimensional (3D) meshes based on forward error correction (FEC). It allows flexible allocation of coding redundancy for reliable transmission over error-prone channels. The proposed scheme is based on progressive geometry compression, which is performed by using wavelet transform and modified SPIHT algorithm. The proposed algorithm is optimized for varying packet loss rates (PLR) and channel bandwidth. Modeling distortion-rate function considerably decreases computational complexity of bit allocation.