This standard specifies technical requirements of surveillance digital video and audio coding and decoding in the field of safety protection.
This standard is applicable to real-time compression, transmission, broadcast, storage and other video and audio business in the field of safety protection, which may be used in other video and audio coding and decoding fields for reference.
2 Normative References
The following standards contain provisions which, through reference in this text, constitute provisions of this standard. For dated reference, subsequent amendments to (excluding correction to), or revisions of, any of these publications do not apply. However, the parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the standards. For undated references, the latest edition of the normative document referred to applies.
GB/T 20090.2-2006 Information Technology-Advanced Coding of Audio and Video-Part2: Video
3 Terminologies, Definitions and Abbreviations
For the purposes of this standard, the following terminologies, definitions and abbreviations apply.
3.1 Terminologies and Definitions
3.1.1
Zig-zag scan
A definite sequence of transform coefficient from lower null field frequency to higher null field frequency (approximate). Zig-zag scan is applicable to transform coefficient in frame macroblock.
3.1.2
B slice
A slice that may be decoded using intra prediction according to the decoded sample in the same slice or using bidirectional prediction according to previously decoded reference picture; inter prediction using at most two motion vectors and reference indices to predict each block.
3.1.3
I slice
A slice that is decoded using intra prediction according to the decoded sample in the same slice.
3.1.4
P slice
A slice that may be decoded using intra prediction according to the decoded sample in the same slice or using forward prediction according to previously decoded reference picture; inter prediction using at most one motion vector and reference index to predict each block.
3.1.5
NAL unit
A syntax structure containing an indication of the type of data to follow and bytes containing that data in the form of an RBSP including authentication data and interspersed as necessary with emulation prevention bytes.
3.1.6
NAL unit stream
A sequence of NAL units.
3.1.7
Reserved
The term reserved, specifying some values of a particular syntax element, is for future use by the working team of Chinese Technical Specification of Surveillance Video and Audio Coding. These values shall not be used in bitstreams conforming to this standard, but may be used in future extensions of this standard.
3.1.8
Closed-loop pitch search
Namely adaptive codebook search, process from weighing input signal to LTP filter state estimation pitch delay
3.1.9
Bitstream
A sequence of bits that forms the representation of coded video and audio and associated data forming one or more coded video and audio sequences. Bitstream is a collective term used to refer either to a NAL unit stream or a byte stream.
3.1.10
Transform coefficient
A scalar quantity, considered to be in a frequency domain, that is associated with a particular one-dimensional or two-dimensional frequency index in an inverse transform part of the decoding process.
3.1.11
Transform coefficient level
An integer quantity representing the value associated with a particular two-dimensional frequency index in the decoding process for computation of a transform coefficient value.
3.1.12
Coded field
A coded representation of a field.
3.1.13
Encoding process
A process that produces a bitstream conforming to this standard, video coding process not specified in this standard.
3.1.14
Encoder
An embodiment of an encoding process, including software and hardware.
3.1.15
Coded video sequence
A sequence of pictures that consists, in decoding order, of an IDR image followed by zero or more non-IDR pictures.
3.1.16
Coded slice NAL unit
A NAL unit containing a slice of a coded picture.
3.1.17
Coded picture
A coded representation of a picture. A coded picture may be either a coded field or a coded frame.
3.1.18
Coded picture buffer
A first-in first-out buffer containing access units in decoding order.
3.1.19
Coded frame
A coded representation of a frame.
3.1.20
Residual
The difference between a predictor of a sample or data element and its decoded value.
3.1.21
Reference field
