Context-adaptive variable-length coding method and system thereof

Abstract

The invention discloses a context-adaptive variable-length coding method and a system thereof. The method comprises the following steps that: a coefficient block that is needed to be coded is mapped as a one-dimensional coefficient array; and according to positional information of all coefficients in the one-dimensional coefficient array, the total number of nonzero coefficients in the one-dimensional coefficient array as well as a position of a first nonzero coefficient and a position of a last nonzero coefficient in the one-dimensional coefficient array are parsed; and with combination of the total number of the nonzero coefficients in the one-dimensional coefficient array, reversed scanning is carried out on all coefficients between the last nonzero coefficient and the first nonzero coefficient in the one-dimensional coefficient array, wherein the last nonzero coefficient and the first nonzero coefficient are contained in all the coefficients, so that coding on an original coefficient block is completed.

Description

technical field [0001] The present invention relates to the field of image processing, in particular to a context adaptive variable length coding method and system. Background technique [0002] The video coding standard H.264 / AVC jointly developed by the International Telecommunication Union Telecommunication Standardization Organization (ITU-T) and the International Organization for Standardization (ISO) is relatively video coding standards MPEG-4, H.263, and MPEG-2. Rates were reduced by 39%, 49%, and 64%, respectively. The H.264 / AVC standard plays an important role in high-definition television (HDTV) applications that require high compression rates, high video quality, and stable transmission bit rates. Research on real-time HDTV encoders has become popular in recent years. [0003] In the H.264 / AVC standard, Context Adaptive Variable Length Coding (CAVLC) is used to encode the quantized transform coefficients of the residual image. In CAVLC, run-length coding with i...

AI Technical Summary

Problems solved by technology

However, the throughput and hardware utilization efficiency of these CAVLC encoders are still not satisfactory due to the following design flaws: 1) low-efficiency full-range scanning processing; 2) separation of scanning phase and encoding phase; Storage requirements for encoded syntax elements

The inefficiency of existing CAVLC encoder designs will be more pronounced due to the reduction in the number of non-zero coefficients in a coefficient block as the quantization parameter (QP) increases

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