Annex 3 to AVC-554R

INTERNATIONAL ORGANIZATION FOR STANDARDIZATION
ORGANISATION INTERNATIONALE DE NORMALISATION

ISO/IEC JTC1/SC29/WG11
CODING OF MOVING PICTURES AND ASSOCIATED AUDIO

ISO/IEC JTC1/SC29/WG11 N0489
(Revised)
MPEG93/            
16 July 1993

Source:	Requirements sub-group	
Title:	Agreements on Profile/Level	
Version:	10 AM, 16 July 1993	

1. Level parameters

Upper bounds are as follows;

	Pels/line	1920	1920	1920	
High	Lines/frame	1152	1152	1152	
(up to 60 Mbit/s)	Frames/sec	60	60	60	
Note 4	Pels/sec	62.7 million	62.7 million	62.7 million	
	Pels/line	1440	1440	1440	
High-1440	Lines/frame	1152	1152	1152	
(up to 60 Mbit/s)	Frames/sec	60	60	60	
Note 4	Pels/sec	47.0 million	47.0 million	47.0 million	
	Pels/line	720	720	720	
Main	Lines/frame	576	576	576	
(up to 15 Mbit/s)	Frames/sec	30	30	30	
Note 4	Pels/sec	10.4 million	10.4 million	11.06 million
(Note 2)	
	Pels/line	352	352		
Low	Lines/frame	288	288	Not decided	
(up to 4 Mbit/s?)	Frames/sec	30	30		
	Pels/sec	2.53 Million	2.53 Million		

Level
(Note 1)	Simple
4:2:0
single layer	Main
4:2:0
single layer	Next
4:2:2
scalable	
	Profile	

Note 1 -	Level for the Next profile indicates the upper layer of the two resolution scales.
Note 2 -	720x512x30 has been considered to accommodate 483 active lines of 525/60 TV.  The extension of the upper bound of the pel rate to cover half SCIF is an open issue.
Note 3 -	Multiples of 16 up to the upper bound are supported in number of pels per line and number of lines per frame.
Note 4 -	Data rates for other than MP@ML are to be determined .

2. Specifications for Next Profile

The Next Profile will support the following functionalities in addition to those of the Main Profile;

#	Functionality	NEXT	Main	
1	Chroma format	4:2:2 and equivalent formats in other resolutions	4:2:0	
2	Flexibility in bit rates (range of bit rates, CBR/VBR)	Independent control of bit rate on each layer is required.	Yes	
3	Random access / Channel hopping	The same as main - the video decoder contributes only a part of the overall access time as seen by the viewer, thus no restrictions are set to the codec delay itself.

A desirable figure for video and audio delay (*1) is less than 0.5 seconds.	Yes, but not necessarily at every frame	
4	Editability	Yes as Main Profile	Yes, but not necessarily at every frame	
5	Resilience	The same as Main - in addition increased error resilience and graceful degradation (*2) may be provided by use of the scalable coding.  See §9.	Yes	
6	Video windowing (e.g. 4:3 from 16:9 pictures)	16:9 needs to be provided for both HDTV and EDTV transmissions.

For display on 4:3 (TV) receivers, signaling of the proportion of a 16:9 picture to be displayed is required.

Video windowing should be possible in each layer.	Yes	
7	Low delay	The same as Main.	Yes	
8	Trick modes	Simple Fast Forward and Reverse are required.

It should be possible that data rate in FF/FR mode be kept at less than normal mode rate.	Yes; those automatically supported by the basic syntax	
9 	Scalability (Hierarchical)	The following should be supported at High-1440 or High Levels;

• up to 2 resolution scales
• up to 4 scales in total as 
   combination of resolution 
   scales and SNR scales
• up to 2 SNR scales at the 
   upper resolution scale

At Main Level,

• up to 2 resolution scales
• up to 3 scales in total as 
   combination of resolution 
   scales and SNR scales

It shall be possible to decode single resolution scale as a degenerate case.

Flexibility in formats at each layer (e.g. resolution ratio other than 2:1) is required for format compatibility and for the letter-box.

Scalable technique with better efficiency than simulcast is required.	No	
10	Compatibility	Forward compatibility with Main Profile is required.  Backward compatibility with MPEG-2 (MP), MPEG-1 and H.261 is required to be possible when MPEG-2 (MP), MPEG-1 and H.261 is used for the base layer of multiple layers (*3).

Downward / upward compatibility is inherent in scalable requirement.	Yes, but only MPEG-1 forward compatibility 	
11	Quality	It should be possible to trade subjective picture quality with bit rate and coding complexity.  See §2.		
12	Flexibility in Implementation	Encoder flexibility in the set of modes provided, M value, in mode selection criteria, motion estimation, pre-analysis, quantization strategy, and other issues not being part of the standard.

Target of software decoding of the lower level is foreseen for IT applications.	Yes	
13	Copyright and copy management (new requirement)	The same as Main	To be contained in the Systems layer	

*1	Time from the reception of the first coded bit and to the representation of visually recognizable picture

*2	Graceful degradation provides the ability for the progressive reduction of picture quality as the error rate  in the bit stream increases. The reduction in picture quality may be continuous or in discrete stages, and may be achieved by mechanisms such as reduction in picture resolution or picture PSNR.

*3	Backward compatibility may not be an important consideration in some applications, particularly if it affects any other of the requirements.

	Forward compatibility with MPEG2 MP@ML is required for conformance at corresponding level. Other levels may not require this functionality.

	Forward compatibility with MPEG1 constrained parameter is required for conformance at this level. Other levels may not require this functionality.

3. Specifications for Simple Profile

Main Profile minus B-pictures.  Dual Prime is retained in the Simple Profile.

4. Forward compatibility between different Profile@Level

X indicates the decoder must be able to decode the bitstream.  

   Decoder
        \
Bitstream	NP
@
HL	NP
@
H-14	NP
@
ML	MP
@
HL	MP
@
H-14	MP
@
ML	MP
@
LL	SP
@
HL	SP
@
H-14	SP
@
ML	SP
@
LL	
NP@HL	X											
NP@H-14	X	X										
NP@ML	X	X	X									
MP@HL	X			X								
MP@H-14	X	X		X	X							
MP@ML	X	X	X	X	X	X		X*	X*			
MP@LL	X	X	X	X	X	X	X	X*	X*	X*		
SP@HL	X			X				X				
SP@H-14	X	X		X	X			X	X			
SP@ML	X	X	X	X	X	X		X	X	X		
SP@LL	X	X	X	X	X	X	X	X	X	X	X	

*	Note that SP@HL and SP@H-14 decoders are required to decode MP@ML and MP@LL bitstreams, and similarly SP@ML decoders are required to decode MP@LL bitstreams.

5. Coding tools not included in defined Profiles

There are some coding tools (4:4:4, 10/8 bit scalability, etc.) which are defined in the syntax but not included in any Profile.  These tools may be included in one or other Profiles which can be added in the future if found necessary according to the existing procedures (e.g. in form of Amendment).  Another possibility is that their use may be defined in application standards.

The November 1993 CD includes only Simple, Main and Next Profiles.

6. Pixel aspect ratio of existing or planned formats

The following values should be included in the WD.

	• 0.7500	1440x1080, 16:9
	• 0.7826	1440x1035, 16:9
	• 1.0435	1920x1035, 16:9

7. Open issues

1) Appropriate naming for Profiles and Levels other than Main
2) Upper bound for the base layer of the Next Profile in terms of resolution and bit rates.
3) Create a table which relates syntactic elements and parameter values with Profiles and Levels.
4) Compatibility with SCIF video format 
5) Bit rate bounds for Profiles and Levels other than MP@ML.

END