H264/AVC1: Profiles and AVC Level 상세스펙

원문: http://en.wikipedia.org/wiki/H.264

AVC레벨에 따른 디코드에 차이가 있다는 내용을 보다가 우연히 발견한 각 AVC프로필과 레벨에 따른 스펙의 차이가 적힌 문서가 발견이 되어서 살펴보았다.

Profiles

The standard includes the following seven sets of capabilities, which are referred to as profiles, targeting specific classes of applications:

• Baseline Profile (BP): Primarily for lower-cost applications with limited computing resources, this profile is used widely in videoconferencing and mobile applications.
• Main Profile (MP): Originally intended as the mainstream consumer profile for broadcast and storage applications, the importance of this profile faded when the High profile was developed for those applications.
• Extended Profile (XP): Intended as the streaming video profile, this profile has relatively high compression capability and some extra tricks for robustness to data losses and server stream switching.
• High Profile (HiP): The primary profile for broadcast and disc storage applications, particularly for high-definition television applications (this is the profile adopted into HD DVD and Blu-ray Disc, for example).
• High 10 Profile (Hi10P): Going beyond today's mainstream consumer product capabilities, this profile builds on top of the High Profile—adding support for up to 10 bits per sample of decoded picture precision.
• High 4:2:2 Profile (Hi422P): Primarily targeting professional applications that use interlaced video, this profile builds on top of the High 10 Profile—adding support for the 4:2:2 chroma subsampling format while using up to 10 bits per sample of decoded picture precision.
• High 4:4:4 Predictive Profile (Hi444PP): This profile builds on top of the High 4:2:2 Profile—supporting up to 4:4:4 chroma sampling, up to 14 bits per sample, and additionally supporting efficient lossless region coding and the coding of each picture as three separate color planes.

In addition, the standard contains four additional all-Intra profiles, which are defined as simple subsets of other corresponding profiles. These are mostly for professional (e.g., camera and editing system) applications:

• High 10 Intra Profile: The High 10 Profile constrained to all-Intra use.
• High 4:2:2 Intra Profile: The High 4:2:2 Profile constrained to all-Intra use.
• High 4:4:4 Intra Profile: The High 4:4:4 Profile constrained to all-Intra use.
• CAVLC 4:4:4 Intra Profile: The High 4:4:4 Profile constrained to all-Intra use and to CAVLC entropy coding (i.e., not supporting CABAC).

As a result of the Scalable Video Coding extension, the standard contains three additional scalable profiles, which are defined as a combination of the H.264/AVC profile for the base layer (2nd word in scalable profile name) and tools that achieve the scalable extension:

• Scalable Baseline Profile: Primarily targeting video conferencing, mobile, and surveillance applications, this profile builds on top of a constrained version of the H.264/AVC Baseline profile to which the base layer (a subset of the bitstream) must conform. For the scalability tools, a subset of the available tools is enabled.
• Scalable High Profile: Primarily targeting broadcast and streaming applications, this profile builds on top of the H.264/AVC High Profile to which the base layer must conform.
• Scalable High Intra Profile: Primarily targeting production applications, this profile is the Scalable High Profile constrained to all-Intra use.

	Baseline	Extended	Main	High	High 10	High 4:2:2	High 4:4:4 Predictive
I and P Slices	Yes	Yes	Yes	Yes	Yes	Yes	Yes
B Slices	No	Yes	Yes	Yes	Yes	Yes	Yes
SI and SP Slices	No	Yes	No	No	No	No	No
Multiple Reference Frames	Yes	Yes	Yes	Yes	Yes	Yes	Yes
In-Loop Deblocking Filter	Yes	Yes	Yes	Yes	Yes	Yes	Yes
CAVLC Entropy Coding	Yes	Yes	Yes	Yes	Yes	Yes	Yes
CABAC Entropy Coding	No	No	Yes	Yes	Yes	Yes	Yes
Flexible Macroblock Ordering (FMO)	Yes	Yes	No	No	No	No	No
Arbitrary Slice Ordering (ASO)	Yes	Yes	No	No	No	No	No
Redundant Slices (RS)	Yes	Yes	No	No	No	No	No
Data Partitioning	No	Yes	No	No	No	No	No
Interlaced Coding (PicAFF, MBAFF)	No	Yes	Yes	Yes	Yes	Yes	Yes
4:2:0 Chroma Format	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Monochrome Video Format (4:0:0)	No	No	No	Yes	Yes	Yes	Yes
4:2:2 Chroma Format	No	No	No	No	No	Yes	Yes
4:4:4 Chroma Format	No	No	No	No	No	No	Yes
8 Bit Sample Depth	Yes	Yes	Yes	Yes	Yes	Yes	Yes
9 and 10 Bit Sample Depth	No	No	No	No	Yes	Yes	Yes
11 to 14 Bit Sample Depth	No	No	No	No	No	No	Yes
8x8 vs. 4x4 Transform Adaptivity	No	No	No	Yes	Yes	Yes	Yes
Quantization Scaling Matrices	No	No	No	Yes	Yes	Yes	Yes
Separate Cb and Cr QP control	No	No	No	Yes	Yes	Yes	Yes
Separate Color Plane Coding	No	No	No	No	No	No	Yes
Predictive Lossless Coding	No	No	No	No	No	No	Yes
	Baseline	Extended	Main	High	High 10	High 4:2:2	High 4:4:4 Predictive

[edit] Levels

Level number	Max macroblocks per second	Max frame size (macroblocks)	Max video bit rate (VCL) for Baseline, Extended and Main Profiles	Max video bit rate (VCL) for High Profile	Max video bit rate (VCL) for High 10 Profile	Max video bit rate (VCL) for High 4:2:2 and High 4:4:4 Predictive Profiles	Examples for high resolution @ frame rate (max stored frames) in Level
1	1485	99	64 kbit/s	80 kbit/s	192 kbit/s	256 kbit/s	128x96@30.9 (8) 176x144@15.0 (4)
1b	1485	99	128 kbit/s	160 kbit/s	384 kbit/s	512 kbit/s	128x96@30.9 (8) 176x144@15.0 (4)
1.1	3000	396	192 kbit/s	240 kbit/s	576 kbit/s	768 kbit/s	176x144@30.3 (9) 320x240@10.0 (3) 352x288@7.5 (2)
1.2	6000	396	384 kbit/s	480 kbit/s	1152 kbit/s	1536 kbit/s	320x240@20.0 (7) 352x288@15.2 (6)
1.3	11880	396	768 kbit/s	960 kbit/s	2304 kbit/s	3072 kbit/s	320x240@36.0 (7) 352x288@30.0 (6)
2	11880	396	2 Mbit/s	2.5 Mbit/s	6 Mbit/s	8 Mbit/s	320x240@36.0 (7) 352x288@30.0 (6)
2.1	19800	792	4 Mbit/s	5 Mbit/s	12 Mbit/s	16 Mbit/s	352x480@30.0 (7) 352x576@25.0 (6)
2.2	20250	1620	4 Mbit/s	5 Mbit/s	12 Mbit/s	16 Mbit/s	352x480@30.7(10) 352x576@25.6 (7) 720x480@15.0 (6) 720x576@12.5 (5)
3	40500	1620	10 Mbit/s	12.5 Mbit/s	30 Mbit/s	40 Mbit/s	352x480@61.4 (12) 352x576@51.1 (10) 720x480@30.0 (6) 720x576@25.0 (5)
3.1	108000	3600	14 Mbit/s	17.5 Mbit/s	42 Mbit/s	56 Mbit/s	720x480@80.0 (13) 720x576@66.7 (11) 1280x720@30.0 (5)
3.2	216000	5120	20 Mbit/s	25 Mbit/s	60 Mbit/s	80 Mbit/s	1280x720@60.0 (5) 1280x1024@42.2 (4)
4	245760	8192	20 Mbit/s	25 Mbit/s	60 Mbit/s	80 Mbit/s	1280x720@68.3 (9) 1920x1080@30.1 (4) 2048x1024@30.0 (4)
4.1	245760	8192	50 Mbit/s	50 Mbit/s	150 Mbit/s	200 Mbit/s	1280x720@68.3 (9) 1920x1080@30.1 (4) 2048x1024@30.0 (4)
4.2	522240	8704	50 Mbit/s	50 Mbit/s	150 Mbit/s	200 Mbit/s	1920x1080@64.0 (4) 2048x1080@60.0 (4)
5	589824	22080	135 Mbit/s	168.75 Mbit/s	405 Mbit/s	540 Mbit/s	1920x1080@72.3 (13) 2048x1024@72.0 (13) 2048x1080@67.8 (12) 2560x1920@30.7 (5) 3680x1536@26.7 (5)
5.1	983040	36864	240 Mbit/s	300 Mbit/s	720 Mbit/s	960 Mbit/s	1920x1080@120.5 (16) 4096x2048@30.0 (5) 4096x2304@26.7 (5)
Level number	Max macroblocks per second	Max frame size (macroblocks)	Max video bit rate (VCL) for Baseline, Extended and Main Profiles	Max video bit rate (VCL) for High Profile	Max video bit rate (VCL) for High 10 Profile	Max video bit rate (VCL) for High 4:2:2 and High 4:4:4 Predictive Profiles	Examples for high resolution @ frame rate (max stored frames) in Level

프로필과 레벨이 높고 좋다고 무조건 전부 다 좋은것이 아니었다.
왜 하드웨어 가속이라던지 디코드에 차이가 생기는지 이제야 알것같다.
AVC프로필과 레벨에 따라 지원되는 스펙이 전부 차이가 있었기 때문이었다.
스펙에 맞지 않으니까 어플리케이션이나 하드웨어가 모를수밖에...
모르니까 가속을 쓸수 없었던것이 아닐까?