mpeg1, mpeg2 and mpeg4 standard comparative analysis and summary
Source https://blog.csdn.net/SoaringLee_fighting/article/details/83627824
mpeg1, mpeg2 and mpeg4 standard comparison
0, the reference
(. 1). The MPEG2, the MPEG4, H264 and difference profile
(2). The MPEG2 standard summary document
(. 3). MPEG1, MPEG2 stream and mpeg4 structural difference analysis
(. 4). The MPEG2 as MPEG- 1 and H.261, H.264 standard techniques (tools) discriminant analysis
(. 5). the JPEG, the MPEG-1, the MPEG-2 and MPEG-4 Comparative process codec
1, the codec process
in detail MPEG1, and MPEG2 codecs may reference flow mpeg4:
the JPEG, the MPEG-1, the MPEG-2 and MPEG-4 codec Process Comparison
MPEG-1 standard is mainly adopted the motion compensated prediction + DCT + quantization + VLC entropy encoding technique based on interpolation; MPEG-2 standard adds Scan process in MPEG-1 based on and codestream syntax added several extension, to support the encoding bit rate higher resolution and more. MPEG-4 encoding standard object oriented primarily to support interactive operation of the application. MPEG-4 decoder into the texture decoder, decoding motion, shape decoder, decoding module face, MPEG-4 standard, the texture decoding module, the MPEG-2 standard based on the increase in the residual DC coefficients after Quant / AC prediction process, further reducing coding redundancy.
2, the structure of the code stream
encoded code stream structure can refer to: MPEG1, MPEG2 and structural differences mpeg4 stream analysis
As can be seen from the three standard hierarchy stream, stream MPEG-1 and MPEG-2 structure is very similar, the only difference is that behind the sequence_header MPEG-2 bitstream must follow the sequence_extension, otherwise MPEG-1 the code stream. Both have a similar layered structure, comprising from top to bottom Sequence, GOP, Picture, Slice, Macroblock , and Block, at the beginning of each layer contains a header, followed by data, each of the header are identified It is determined according to the starting code.
MPEG-4 standard is object-oriented, and therefore also related to the object hierarchy, from top to bottom is the Visual Object Sequence (VS), Video Object (VO), Video Object Layer (VOL), Group of Video Object Planes ( GOV) and a Video Object Plane (VOP), the beginning of each layer contains a header, followed by data, identifying each header is judged according to the starting code.
Note: The standard stream structure different from the previous MPEG-4 standard H.264 of the later alternative, takes the form of nal units, each contained in a respective nal header data and encoded data.
3, the reference frame of
MPEG-1, MPEG2, P MPEG4 standard frame only one reference frame (single reference), B frame may have two reference frames;
the H.264 can have up to 15 reference frame, generally 3-5 selected frame as a reference frame.
4, the encoded bit stream syntax and semantics of
backward compatible because MPEG-2 standard MPEG-1, MPEG-1, and most of the syntax and semantics of the MPEG-2 standard is the same, but does not include the MPEG-1 standard sequence spread data The image data extension and user data extension.
MPEG-4 standard is object-oriented, its syntax and semantics of encoded streams and MPEG-1 and MPEG-2 are great differences.
5, support characteristics between
MPEG-1 standard features supported :( I.6)
Random access
fast forward or rewind (fast search)
Playback
error robustness of
editing
MPEG-2 standard features supported :( Annex D)
Support higher resolution and bit rate:
the MPEG-. 1: up to about 1.5Mbps
the MPEG-2: ~ 100Mbps 3Mbps
the MPEG-support. 1 SIF (352x240 for NTSC, 352x288 for PAL) format, and CPS (Constrained Parameter Set) in the other resolution;
the MPEG-2 standard to support higher resolutions, such as D1,720P like.
Support progressive coding and interlaced coding;
support different chroma sampling format (4: 2: 0 and 4: 2: 2 and 4: 4: 4);
supporting a wide range of image quality.
Random access support
fast forward and fast playback
editing
support MPEG-1 stream decoding
error recovery
MPEG-4 standard supports features :( Annex E)
Error Recovery: GOB resynchronization, data partitioning, reversible VLC
complexity estimation
6, details of the encoding and decoding module Comparative
portion may refer to: the MPEG-2 and MPEG-1 and H.261, H.264 standard techniques (tools) discriminant analysis
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