H.264 Glossary

Raw byte sequence packet (rbsp)

String of data bits (sodb)

PoC: Picture order count

Sequence parameter set (SPS)

Picture parameter set (PPS)

DPB decoding image buffer decoder picture Buffer

The IDR image immediately refreshes the first image in a sequence. The IDR image is an I-frame image.

PAFF means "picture adaptive Field Frame", mbaff means "macroblock adaptive Field Frame ".

* PAFF allows to decide, on a frame basis, whether to encode each frame as a frame or as two fields. when encoded as two fields, it's as if you wowould have done a separatefields () on the frame.

* Mbaff allows to decide, on a macroblock basis, whether to encode as field or frame. actually, it works on vertical pairs of macroblocks, so on 16x32 areas. you can easily put two frame macroblocks (on under the other), or two field ones (one with the top lines, the other with the bottom lines ).

 

Mbaff is the most efficient method in almost every cases (if not all), as soon as the encoder does a proper job, of course.

 

Finally, mbaff and PAFF may be used together. In that case, you can code a frame either as mbaff (thus having the choice field/frame per macroblock) or as field.

UVLC unified Variable Length Encoding

 

Sodp: string of data bits (original data) original bit stream after Coding

Rbsp: Raw byte sequence packe end with 1 and trailing o for alignment adds 1 and a series of zeros to the end of sodp for alignment.

Ebsp: encapsulate byte sequence payload in order

Avoid start code conflict in nalu, add 0x03 affter two ox00

Cabac and cavlc are used only for residual encoding, while other syntax elements are encoded using Columbus or natural binary.

Fidelity range extension: high-precision Extension

EPZs, which is interpreted as enhanced predictive zonal search, can be translated as "Improved Prediction regional search algorithm ",

White service: p210, and white Service (codedblockpattern) refer to the code scheme of sub-Macro Block residual.

Annex B: Keep the encoded h264 stream on the media using the starting code + Nal, that is, the method described in appendix B.

RTP: pack the nal Of the 264 stream into the RTP package according to the standard.

 

NALU is divided into vcl nalu and non-vcl nalu (see the semantic explanation of nal_unit_type in section 7.4.1 of the 200503 standard). what I call "If data splitting is not used, one slice is a NALU, a nalu is a piece. Otherwise, a piece is composed of three NALU. The value of nal_unit_type in standard table 7-1 is 2, 3, the three nalus of 4 belong to one slice "is for vcl nalu. The concept of slice is only applicable to vcl nalu. Therefore, SPS and PPS are neither slice nor slice.

 

The byte stream format is mainly used for file storage. Therefore, in the bitstream format, there is only one starting prefix before NALU.

Due to the need for network transmission, there is a lot of auxiliary information before NALU.

 

The main purpose of dividing ABC slices is to protect data of different importance levels to different degrees.

 

Highprofile (HP)

Mainprofile (MP)

Umhexagons: Asymmetric cross-shaped multi-layer hexagonal lattice Motion Search Algorithm

 

 

Rate Distortion Curve:

The rate distortion (RD) curve reflects the encoding performance of different encoders.

Generally, the RD curve uses the bit rate (Kbps) as the abscissa, And the SNR (db) as the ordinate to generate a curve. The points on the curve generally use QP = 28, 32, the coding bit rate and quality (QPI, butrate, and SNR) of QP ).

The higher the curve, the better the performance.