International organisation for standardisation organisation internationale de normalisation

HEVC

In coordination with JCT-VC and JCT-3V, which met in parallel under ITU-T WP3/16 auspices, the following HEVC-related documents were approved as outputs:

• 
  N13931 Defect Report on 23008-2:201X
  
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  N13932 HEVC Verification Test Plan Draft 2
  
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  N13933 Study text of ISO/IEC 23008-2:201x/DAM1 HEVC Range Extensions
  
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  N13934 Study text of ISO/IEC 23008-2:201x/DAM2 HEVC Multiview Extensions
  
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  N13935 Study text of ISO/IEC 23008-2:201x/PDAM3 HEVC Scalable Extensions
  
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  N13936 Working Draft 2 of 3D-HEVC
  
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  N13937 High Efficiency Video Coding (HEVC) Encoder Description v 13 – (HM13)
  
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  N13938 HEVC RExt Test Model 1
  
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  N13939 Scalable HEVC (SHVC) Test Model 4 (SHM 4)
  
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  N13940 Test Model 6 of 3D-HEVC and MV-HEVC
  
• 
  N13942 Study text of ISO/IEC DIS 23008-8 HEVC Conformance
  

1. Jointly-discussed requirements-related issues

Several related issues were discussed in two joint meetings (Monday at 1600 and Thursday at noon) with MPEG Requirements and VCEG participation as well as members of JCT-VC and JCT-3V. See also the Requirements, JCT-VC, and JCT-3V reports. The discussion primarily focused on profiles for the range extensions of HEVC. A study text was issued for consideration by NBs during preparation of their comments on the ongoing DAM ballot.

2. General HEVC Issues

Two particular topics that arose in the joint discussions that affect multiple projects were the following:

• 
  Ultra-low-delay operation with layered coding, such that the coded layers for a given access unit might need to be interleaved within the picture level (e.g., not sending the full picture for one view of multiview video before sending part of the picture for another view, or similarly spatially interleaving the coded data of scalable layers). This was agreed to have significant complexity implications, to the degree that it was not planned for currently developing profiles and was agreed to require further study before this feature could be specified in some future profile.
  
• 
  Sending supplemental information as "auxiliary pictures" or in a "frame packing arrangement". It was agreed to plan to support the capability to send auxiliary pictures with an indication of the type of supplemental picture. However, it was noted that there are several potential approaches for sending high-resolution chroma information (e.g., ordinary 4:4:4 coding, auxiliary monochrome chroma planes, and the use of a frame packing arrangement to use a 4:2:0 decoding process to decode data that could be rearranged to form 4:4:4 decoded pictures). It was agreed that further technical study of these approaches was needed.
  

3. HEVC Range Extensions

The following plans were initially recorded in notes of joint discussions in regard to profile specification modifications for the HEVC range extensions study text, pending confirmation from ballot responses.

• 
  To plan to add all-intra profiles (for bit depths not including 14 bit as noted below, requiring output order to be equal to decoding order and all pictures to be IRAP pictures – with in-loop filtering to be considered optional as in AVC all-intra profiles).
  
• 
  To plan to add 12 and 16 bit monochrome profiles.
  
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  To plan to add a 4:4:4 8 bit profile (see clarification of status below).
  
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  To not include the following in the output draft, pending further study:
  
  • 
    Non-4:2:0 14 bit profiles
    
  • 
    4:4:4 16 bit profile
    
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  In 4:2:0 and 4:2:2 profiles, planning to prohibit TS rotation, TS context, intra BC, intra/inter RDPCM, intra smoothing disabling, large-block TS, Rice parameter initialization modification
  
• 
  In regard to chroma QP adaptation modification, not to plan to include this feature in 4:2:0 profiles but to include it in 4:2:2.
  
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  To plan to allow cross-component color prediction in 4:4:4 profiles (see clarification of status below).
  
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  To otherwise not prohibit any applicable features.
  
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  To plan to enable high-precision weighted prediction in all profiles supporting > 8 bit video.
  

Further study on tools was planned to confirm these selections.

However, after the joint meetings, WG 11 concluded that it had a lack of consensus on the precise specification of 4:4:4 profiles and that no proposed changes to 4:4:4 profile definitions had been agreed to at the 106th MPEG meeting. Therefore, any such planned changes recorded above or in the JCT-VC meeting report, relative to the output of the prior (Vienna) meetings, do not represent a consensus of WG 11 to plan for adoption of such changes. Such changes are documented herein only to reflect the recorded state of the joint discussions that ended prior to the closing of the WG 11 meeting. A WG 11 resolution was recorded on this topic.

Since WG 11 had no consensus on changes to the 4:4:4 profile definitions, the Study Text prepared for WG 11 purposes was prepared without including such changes, although such changes are reflected in the JCT-VC output draft. The differences between the two outputs should be resolved at the January 2014 meeting in San José.

Definition of tiers and levels remained TBD.

4. HEVC Scalable Extensions

A particular topic of discussion for scalable coding was so-called "hybrid" scalability in which the base layer(s) are coded with AVC and the enhancement layer(s) are coded as SHVC enhancement layers.

Basic questions included the following:

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  Should the HEVC profile/tier/level conformance specification include the base layer within its scope?
  
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  Should we specify encapsulation of AVC in HEVC?
  
• 
  Should we specify encapsulation of HEVC in AVC?
  

The two encapsulation approaches are under consideration for technical study, not yet endorsed as planned supported types. The external systems mux approach to this type of operation is agreed as being planned. The JCT-VC issued a document documenting designs under consideration.

14.1.1.1.1.1.1.1.81m31394 Capability of transcoding-friendly scalable video coding [Kenneth Andersson, Thomas Rusert, Rickard Sjöberg, Jonatan Samuelsson (Ericsson)]

This contribution was considered to be related to requirements and was identified for further study. A closely related contribution JCTVC-O0127 was also submitted to JCT-VC.

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