KR20160059512A - Method and apparatus for decision of initial block vector search point and search range of intra block copy in video encoder - Google Patents

Abstract

The present invention includes a step of determining an initial position of a block vector search and setting a search range of a block vector to produce a prediction block when the block vector search of an intra block copy technique is performed in a video encoder. Therefore, a speed of the intra block copy technique can be increased.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for determining a block vector search start position and a search range of an in-

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video coding technique, and more particularly, to a block vector search start position determination and a search range setting of an in-screen block copy technique.

Recently, with the development of computer graphics technology, the improvement of digital contents production technology, and the spread of multimedia devices, demand for screen contents video is increasing in various fields such as remote video conferencing, broadcasting contents, education, and animation. Since the existing video compression technology including High Efficiency Video Coding (HEVC), which is a high efficiency video compression technology for recent high resolution and high image quality, has been developed focusing on the compression of natural image, Coding efficiency is not good. Screen Content Coding (SCC) research has been actively carried out to efficiently compress the screen content image. According to the Call for Proposal (CfP) issued on January 17, 2014, the SCC standardization work with the HEVC extension technology .

The present invention relates to a method and apparatus for improving the speed of in-screen block copying technology by setting a search start position and a range in performing a block vector search of an intra-picture block copy technique (IBC) in a video encoder.

According to an aspect of the present invention, there is provided a method for searching a block vector of an in-screen block copy technique in a video encoder, the method comprising: determining a start position of a block vector search, .

According to an embodiment of the present invention, a method of searching a block vector of an in-screen block copy technique in a video encoder determines a start position of a block vector search and performs a search within a set range to generate a prediction block, The encoding time can be shortened.

1 is a block diagram of a general screen contents coding apparatus.
2 is a block diagram of a general screen content coding and decoding apparatus.
3 is a conceptual view of a general in-screen block copy technique.
FIG. 4 is a conceptual view of a block vector prediction method of a general intra-picture block copying technique.
FIG. 5 is a diagram illustrating an example of the start position determination of a block vector search in the in-screen block copy technique proposed in the present invention.
FIG. 6 is a block diagram illustrating a block vector search method of an in-screen block copy technique proposed in the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following description of the embodiments of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present disclosure rather unclear.

It is to be understood that the description as to a specific configuration does not exclude a configuration other than the configuration of the present invention and that additional configurations may be included in the scope of the present invention or the scope of the present invention.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component.

In addition, the components shown in the embodiments of the present invention are shown independently to represent different characteristic functions, which does not mean that each component is composed of separate hardware or software constituent units. That is, each constituent unit is included in each constituent unit for convenience of explanation, and at least two constituent units of the constituent units may be combined to form one constituent unit, or one constituent unit may be divided into a plurality of constituent units to perform a function. The integrated embodiments and separate embodiments of the components are also included within the scope of the present invention, unless they depart from the essence of the present invention.

In addition, some of the components are not essential components to perform essential functions in the present invention, but may be optional components only to improve performance. The present invention can be implemented only with components essential for realizing the essence of the present invention, except for the components used for the performance improvement, and can be implemented by only including the essential components except the optional components used for performance improvement Are also included in the scope of the present invention.

The block used in the invention may be a basic block unit of coding, a prediction block unit, or a conversion block unit. The block boundary may be a boundary of a coding block, a boundary of a prediction block, or a boundary of a transform block.

1 is a block diagram of a general screen contents coding apparatus. An inter picture prediction unit 101, a reconstructed picture buffer 102, an intra prediction unit 103, an in-picture block copying unit (hereinafter referred to as an intra-picture prediction unit) A palette mode unit 105, an adaptive color conversion unit 106, an intercolor prediction unit 107, a change unit 108, a quantization unit 109, an entropy encoding unit 110, an inverse quantization unit 111, an inverse transform unit 112, an adaptive color inverse transform unit 113, a deblocking filter unit 114, a sample adaptive offset unit 115, and the like.

2 is a block diagram of a general screen content coding decoding apparatus. An inverse quantization unit 201, an inverse transformation unit 202, an inter-color prediction unit 203, an adaptive (inverse quantization) An in-picture block predictor 207, an in-picture block copying unit 208, a pallet mode unit 209, a deblocking filter unit 207, a color inverse transform unit 204, an inter picture prediction unit 205, a reconstructed picture buffer 206, (210), a sample adaptive offset unit (211), and the like.

3 is a conceptual view of a general in-screen block copy technique. In the in-picture block copying technique, the block 300 to be coded at present is a prediction technique for finding a block 303 with the best matching with its own block among the restored area 302 in the same frame 301, It is not possible to refer to the area 304 that is not included.

FIG. 4 is a conceptual view of a block vector prediction method of a general intra-picture block copying technique. The order of selecting two predictive block vector candidates for block vector prediction and selecting the predictive block vector candidates in the encoding process can be firstly used for the lower left and upper right blocks of the current block through the neighboring block checking unit 400 It is checked whether there is a block vector. For details, refer to the description of FIG. If two predictive block vector candidates are not satisfied through the neighboring block checker, a block vector for two blocks newly coded / decoded in the in-screen block copy is used through the past block vector checker 401, It is not used if it overlaps with the value already filled in the prediction block vector candidate. If the predicted block vector candidates are not satisfied even through the block vector checking unit, the basic vector value is used through the basic vector using unit 402, and then the predicted block vector candidate Lt; / RTI > In the decoding process, the process up to the basic vector using process is the same, and the prediction performing unit selects one of the two predictive block vector candidates using the information sent from the encoder.

FIG. 5 is a diagram illustrating an example of the start position determination of a block vector search in the in-screen block copy technique proposed in the present invention. Let block 1 (501) and block 2 (502) denote blocks indicated by two predicted block vector candidates obtained by performing block vector prediction before performing block vector search. The start position determination of the block vector search proposed in the present invention determines the block vector of the block in which the difference value is smaller through the difference between the block 1 and the block 2 in the block 500 to be encoded at present as the start position. If the values of the block 1 and the block 2 are the same for the current block to be encoded, the following selection algorithm can be added.

When the difference values between the block 1 and the block 2 are the same, the quantized coefficients are selected through conversion and quantization. If the quantized coefficients are the same, the first or second candidate vector among the predicted block vector candidates is set to the start position .

FIG. 6 is a block diagram illustrating a block vector search method of an in-screen block copy technique proposed in the present invention. Before starting the block vector search in the current block to be coded by the in-picture block copy technique, the start position of the block vector search is determined through the block vector search start position determiner 600, It is the same as the contents. The block vector search range setting unit 601 sets the search range and can set the search range before performing the encoding. The block vector search early termination determiner 602 performs a block vector search. If the difference between the block vector search block and the current block to be coded is smaller than a preset threshold value, the search is terminated. Can be changed.

Not applicable

Claims (1)

A video encoding method comprising:
Determining to perform coding through an in-screen block copy method;
Setting a range of a block vector search to perform the block copy method; And
Determining a block to be copied within the search range and generating a prediction block;

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