Low Complexity Trellis-Coded Quantization in Versatile Video Coding.

Area of Science:

• Video Compression Technology
• Digital Signal Processing
• Information Theory

Background:

• The Versatile Video Coding (VVC) standard utilizes trellis-coded quantization for high compression efficiency.
• The complexity of trellis search and soft-decision quantization in VVC can limit practical applications due to high computational demands and low throughput.
• Optimizing quantization processes is crucial for efficient video encoding and decoding.

Purpose of the Study:

• To propose a novel, low-complexity trellis-coded quantization scheme for the VVC standard.
• To theoretically model the rate-distortion performance of the proposed scheme.
• To reduce the computational complexity and improve the throughput of VVC quantization.

Main Methods:

• Development of a low-complexity trellis-coded quantization scheme.
• Adaptive adjustment of trellis departure points and pruning of unnecessary branches.
• Theoretical modeling of rate and distortion characteristics.
• Experimental evaluation using the VVC test model.

Main Results:

• Significant reduction in encoding complexity (11% for all-intra, 5% for random access).
• Minimal increase in BD-Rate (0.11% for all-intra, 0.05% for random access).
• Substantial savings in quantization time (24% for all-intra, 27% for random access).

Conclusions:

• The proposed low-complexity trellis-coded quantization scheme effectively reduces VVC encoding complexity and time.
• The scheme achieves excellent performance with a negligible impact on compression efficiency.
• The VVC test model has incorporated an implementation of this optimized quantization scheme.