GB/T 20090.2-2006 in English

《GB/T 20090.2-2006信息技术 先进音视频编码 第2部分:视频》由TC28（全国信息技术标准化技术委员会）归口，TC28SC29（全国信息技术标准化技术委员会多媒体分会）执行，主管部门为国家标准化管理委员会。
GB/T 20090规定了数字音视频的压缩、解压缩、处理和表示的技术方案，适用于高分辨率和标准分辨率数字电视广播、激光数宁存储媒体、互联网宽带流媒体、多媒体通信等应川。GB/T 20090的本部分规定了多种比特率、分辨率和质量的视频压缩方法，适用于数字电视广播、交互式存储媒体、直播卫星视频业务、多媒体邮件、分组网络的多媒体业务、实时通信业务、远程视频监控等应用，并且规定了解码过程。

1 Scope

GB/T 20090 specifies technical schemes for compression, decompression, processing and representation of digital audio and video and is applicable to applications such as high-resolution and standard-resolution digital television broadcasting, laser digital storage media, Internet broadband streaming media and multimedia communication.
This part of GB/T 20090 specifies diversified bit rate, resolution and quality of video compression methods as well as decoding process, and is applicable to digital television broadcasting, interactive storage media, direct broadcast satellite video services, multimedia mail, multimedia services on packet network and remote video surveillance.

2 Normative References

The following documents contain provisions which, through reference in this text, constitute provisions of this part. For dated reference, subsequent amendments to (excluding correction to), or revisions of, any of these publications do not apply. However, the parties whose enter into agreement according to this part are encouraged to research whether the latest editions of these documents are applied or not. For undated references, the latest edition of the normative document applies.
GB/T 14857-1993 The Specifications of Encoding Parameters of Digital Television for Studio (eqv CCIR 601-3)

3 Term and Definitions

For the purpose of this part, the following terms and definitions apply.
3.1
Reserved
Some specific syntax element values are defined to be used for future expansion of this part.
Note: these values shall not appear in the bitstream in accordance with this part.
3.2
Bit string
The ordered sequence with limit bit, in which the leftmost bit is the most significant bit (MSB) and the rightmost bit is the least significant bit (LSB).
3.3
Bitstream
The binary data stream formed by the coded picture.
3.4
Bitstream buffer
The buffer for storing bitstream.
3.5
Bitstream order
The sort order of the coded picture in the bitstream, which is the same as the picture decoding order.
3.6
Variable length coding
One reversible entropy coding process, which allocates the short code word to the sign with relatively high frequency and the long code word to the symbol with relatively low frequency.
3.7
Transform coefficient
One scalar in the transform domain.
3.8
Encoding presentation
The form after the data encoding.
3.9
Encoding process
The process to produce the bitstream in accordance with this part.
Note: this process is not specified in this part.
3.10
Encoder
The realization of the encoding process.
3.11
Coded picture
Encoding presentation of one frame of picture.
3.12
Flag
One binarystate variable.
3.13
Compensation
The sum of the sample residual obtained by decoding the syntax element and its corresponding prediction value.
3.14
Residual
The difference between reconstructed value of the sample or data element and its prediction value.

Foreword I
Introduction II
0.1 Objective II
0.2 Application II
0.3 Profile and Level II
0.4 General Technology II
0.4.1 Prediction Technology II
0.4.2 Picture Block II
0.4.3 Tansform and Quantization III
0.5 How to Read this Part III
0.6 Description on Relevant Patent Condition III
1 Scope
2 Normative References
3 Term and Definitions
4 Abbreviations
5 Stipulation
5.1 Arithmetic Operators
5.2 Logical Operators
5.3 Relational Operators
5.4 Bitwise Operators
5.5 Assignment
5.6 Mathematical Function
5.7 Bitstream Syntax, Parse and Decoding Process Description
5.7.1 Description Method
5.7.2 Function
5.7.3 Descriptor
5.7.4 Reserved, Forbidden and Marker
6 Structure of Coded Bitstream
6.1 Video Sequence
6.1.1 Progressive and Interlaced Video Sequence
6.1.2 Sequence header
6.2 Picture
6.2.1 Picture Format
6.2.2 Picture Type
6.2.3 Picture Order
6.2.4 Reference Picture
6.3 Slice
6.4 Macroblock
6.5 8×8 Block
7 Syntax and Semanteme of Bitstream
7.1 Syntax Description
7.1.1 Start Code
7.1.2 Definition of Video Sequence
7.1.3 Definition of Picture
7.1.4 Definition of Slice
7.1.5 Definition of Macroblock
7.1.6 Definiton of Block
7.2 Semantic Description
7.2.1 Video Extension
7.2.2 Video Sequence
7.2.3 Picture
7.2.4 Slice
7.2.5 Macroblock
7.2.6 Block
8 Parse
8.1 K-level Index Columbus Code
8.2 ue(v), se(v) and me(v)
8.3 ce (v)
9 Decoding Process
9.1 High-level Syntax Structure
9.2 Decoding of Picture Headerer
9.3 Slice Decoding
9.4 Macroblock Decoding
9.4.1 Macroblock Type
9.4.2 Intra Prediction Mode
9.4.3 Reference Picture Selection
9.4.4 Motion Vector
9.4.5 Macroblock Coding Template
9.4.6 Quantization Parameter
9.5 Block Decoding
9.5.1 Variable Length Coding Decoding
9.5.2 Inverse Scan
9.6 Dequantization
9.6.1 Quantization Parameter Determination
9.6.2 Dequantization
9.7 Inverse Transform
9.8 Intra Prediction
9.8.1 Obtaining of Reference Sample
9.8.2 Luma Block Intra Prediction
9.8.3 Chroma Block Intra Prediction
9.9 Inter Prediction
9.9.1 Luma Motion Vector Derivation
9.9.2 Derivation Process of Reference Sample
9.9.3 Weighting Prediction
9.10 Reconstruction
9.11 Loop Filter
9.11.1 Derivation process of Boundary Filtering Strength
9.11.2 Derivation Process of Block Boundary Threshold
9.11.3 Boundary Filtering Process Where Bs is Equal to 2
9.11.4 Boundary Filtering Process Where Bs Is Equal to 1
Appendix A (Normative) Table of Variable Length Coding
Appendix B (Normative) Profile and Level
B.1 Profile
B.2 Level
B.2.1 Level Defined in This Part
B.2.2 Level Limit Irrelevant to Profile
Appendix C (Normative) Pseudo Start Code
Appendix D (Normative) Bitstream Buffer Verifier
D.1 Stipulation
D.1.1 Stipulation I
D.1.2 Stipulation II
D.1.3 Stipulation III
D.2 Basic Operation
D.2.1 Data Input
D.2.1.1 Method I
D.2.1.2 Method II
D.2.2 Data Shiftout
D.2.2.1 Non-low Delay
D.2.2.2 Low Delay
D.3 Buffer Detection Time Interval
D.3.1 Non-low Delay
D.3.2 Low Delay