A method and system for intra-frame coding optimization based on mode preprocessing

A technology of intra-frame encoding and optimization method, applied in the field of video processing, can solve the problems of low encoding speed, unstable complexity, and inability to fundamentally guarantee the real-time encoding function.

CN103702131BInactive Publication Date: 2017-02-15TSINGHUA UNIV +1
5 Cites 0 Cited by

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Patents(China)
Current Assignee / Owner
Publication Date
2017-02-15
Estimated Expiration
Not applicable · inactive patent

Smart Images

  • Figure 1
    Figure 1
  • Figure 2
    Figure 2
  • Figure 3
    Figure 3
Patent Text Reader

Abstract

The invention provides a pattern-preprocessing-based intraframe coding optimization method and a pattern-preprocessing-based intraframe coding optimization system. The method comprises the following steps of 1, dividing a coding tree unit of an original image into a plurality of N*N coding units, and calculating the edge strength of each point in the coding units, wherein N belongs to {4,8,16,32}; 2, classifying all the N*N coding units based on coding unit edge strength analysis, wherein N belongs to {4,8,16,32}; 3, selecting a corresponding residual estimation model according to a classification result, and performing pixel prediction error estimation on each N*N coding unit, wherein N belongs to {4,8,16,32}; 4, calculating the overall coding rate distortion cost RDN of each N*N coding unit according to the pixel prediction error estimation of the N*N coding unit, wherein N belongs to {4,8,16,32}; 5, when N belongs to {4,32}, calculating the segmented coding cost of each N*N coding unit, namely cost in the segmentation of each N*N coding unit into four corresponding coding units; 6, when N belongs to {8,32}, comparing an overall coding rate distortion cost value and a segmented coding cost value of each N*N coding unit, not segmenting the N*N coding unit if the overall coding rate distortion cost value is less than the segmented coding cost value, otherwise segmenting the N*N coding unit into four corresponding coding units.
Need to check novelty before this filing date? Find Prior Art

Description

technical field

[0001] The present invention relates to the technical field of video processing, in particular to an intra-frame coding optimization method and system based on mode preprocessing. Background technique

[0002] High Efficiency Video Coding (HEVC, High Efficiency Video Coding) is a more popular coding standard after the H.264 / AVC standard. In order to properly handle image sequences in high-definition and ultra-high-definition resolutions, HEVC proposes a composite coding unit (CTU, coding tree unit). A complete frame of image, regardless of its resolution, will be divided into coding tree units (CTUs) consisting of 64×64 luminance pixel lattices and corresponding chrominance pixel lattices at the beginning of its encoding, and then CTU is the unit and is encoded sequentially. Because chroma encoding is similar to luminance, and its complexity is simpler than that of luminance, discussions on the complexity of HEVC encoding generally focus on the encoding of ...

Examples

Embodiment 1

[0087] Embodiment 1 of the present invention proposes an intra-frame coding optimization method based on mode preprocessing. This method is applied to the coding tree unit CTU before coding the pixel lattice of the coding tree unit CTU. Specifically, from 32 / 16 Select one of the two coding blocks CU, the selection result is called LCB (Large Code Block), choose one of the 8 / 4 two coding blocks CU, and the selection result is called SCB (Small Code Block), so that the frame The calculation amount of inner encoding is reduced by nearly half, and two sets of pattern search engines can be used to realize parallel encoding, thus stably speeding up the encoding process. see figure 1 , the method comprises the steps of:

[0088] Step 101: Divide the coding tree unit of the original image into several N×N coding blocks, N∈{4,8,16,32}, and calculate the edge strength of each point in the coding block.

[0089] In this step, we assume that the coding tree unit CTU of the original ima...

Embodiment 2

[0130] Embodiment 2 of the present invention also proposes an intra-frame coding optimization system based on mode preprocessing, see figure 2 , the system consists of:

[0131] The edge strength calculation module 201 is used to divide the coding tree unit CTU of the original image into several N×N coding blocks CU, N∈{4,8,16,32}, and calculate the edge strength of each point in the coding block;

[0132] A coding block classification module 202, configured to classify all N×N coding blocks based on the edge strength analysis of coding blocks, N∈{4,8,16,32};

[0133] The coding block prediction error estimation module 203 is used to select a corresponding residual estimation model according to the classification result to perform pixel point prediction error estimation on each N×N coding block, N∈{4,8,16,32};

[0134] The overall encoding cost calculation module 204 is used to calculate the overall encoding cost RD of each N × N encoding block according to the pixel point p...