_____________________________________________________________________ ITU - Telecommunications Standardization Sector Document: ITU-LBC-96-149 STUDY GROUP 15 LBC Experts Group Dallas, USA, April 22-25, 1996 Title: H.263+ Video Group Meeting Report Source: H.263+ Video Group Chair Contact: Gary J. Sullivan Voice: +1 508 623 4324 PictureTel Corp. M/S 635 Fax: +1 508 749-2804 222 Rosewood Dr. Email: garys@pictel.com Danvers, MA 01923 USA _____________________________________________________________________ 1. Introduction The H.263+ development effort is intended for near-term standardization of enhancements of the H.263 video coding algorithm for real-time telecommunication. The H.263+ group held meetings throughout the April 22-25 LBC Experts Group meeting, and is pleased to report that it made significant progress toward its goal. The group's activities during this week can be summarized as follows: a) We agreed on the scope and goals of our work effort b) We defined our workplan schedule c) We reviewed 3 contributions providing guidance for the conduct of our efforts d) We adopted guidelines and test conditions for use in experiments and proposals e) We adopted a simulation test model definition to use as the basis for experiments f) We collaborated jointly with the H.263L and Mobile Video groups g) We reviewed 12 technical proposals for algorithm and syntax features h) We identified 9 key technical areas for core experiment definition i) We appointed coordinators for rapid (within two weeks) definition of core experiments in each identified key technical area j) We completed the definition of core experiments in 3 of the 9 technical areas The following sections describe these activities in greater detail. 2. Scope, Goals and Schedule The H.263+ group agreed on the scope, goals, and workplan schedule for its activities, and provided a written description of these intentions in document LBC-96-148. 3. Guidelines and Test Conditions for H.263+ Work The group reviewed 3 contributions providing guidance for the conduct of our efforts: Document Company Subject Summary LBC-96-104 PictureTel Proposed Goals and Schedule LBC-96-111 Iterated Systems Guidelines for Core Experiments LBC-96-112 Iterated Systems Display Formats and Video Delay Display The following guidelines and reference test model were adopted to guide the work of those wishing to make H.263+ contributions: a) Email communications for our group will be conducted using the advanced video email reflector provided by Iterated Systems: sg15_lbc_adv_video@listserv.iterated.com b) The reference test model, currently TMN6 as described in LBC-96-141 should be used as a basis for core experiment comparisons c) The exchange of software among the members of the group is encouraged for easing the burden on those wishing to make contributions d) However, core experimenters should not exchange software to implement the tested features of the experiment (in order to aid work on developing written descriptions of the features by ensuring that descriptions provide sufficient information for unambiguous interpretation) e) At least two companies are expected to perform any core experiment prior to the adoption of a tested feature into H.263+ f) Proposers of core experiments are expected to provide draft text for writing the H.263+ recommendation description of the tested feature g) Decoding of bitstreams is expected from core experimenters prior to reporting results (in order to ensure proper testing of the associated syntax features) h) Fixed frame rate, fixed QP tests are useful for evaluating compression efficiency performance i) The possibility of interactions between optional features of the H.263+ syntax will be considered and evaluated j) Additional test condition recommendations (including recommended test sequence data, frame rates, and display conditions) are adopted per the report of the video test conditions special task group LBC-96-138, and further refined as a result of discussions in the H.263L meeting. These STG conclusions appear in LBC-96-139. 4. Joint Collaboration The H.263+ video group held joint discussions with the H.263L video group in order to coordinate the efforts of the two groups. In particular, the guidelines and test conditions for the two groups were developed through joint efforts. The viewing of video demonstrations was conducted jointly, and several technical proposals were presented with evaluation of their applicability toward the goals and schedules of the two projects. The H.263+ video group also held joint sessions with the Mobile video group for evaluation of the guidelines and test conditions appropriate for the two groups, for presentation of technical proposals of joint interest, and for viewing of demonstration videos having Mobile video ramifications. 5. Evaluation of Technical Contributions The H.263+ video group held presentations of 12 technical contributions: Document Company Subject Summary LBC-96-084 PictureTel Modulated Lapped Transform LBC-96-085 PictureTel Reduced Delay Syntax LBC-96-087 Oki Error Resilient Coding LBC-96-091 Nokia Variable Segmentation Video Coding LBC-96-096 Deutsche Tel. Loop Filter Evaluation LBC-96-097 Telenor Intra Picture Predictive Coding LBC-96-098 Telenor Variable Size (8x8 and 4x4) DCT LBC-96-099 Telenor Reducing Video Delay LBC-96-116 Natl. Semic. Corp. GOB Source Format LBC-96-117 Natl. Semic. Corp. Adaptive Arithmetic Coding LBC-96-118 Natl. Semic. Corp. Video Frame Size Quadrupler LBC-96-132 Intel Error Resilient Syntax 6. Key Technical Areas of Contributions The H.263+ video group identified 9 key technical areas in which proposal contributions had been provided. The group agreed that these areas were worthy of further investigation, and appointed a coordinator to provide a core experiment description for each. The coordinators volunteered to provide these C.E. descriptions to the group (via email or current meeting contribution) within two weeks, and several of them have in fact already fulfilled this commitment as noted below: Technical Feature Area Related Doc. #s Coordinator C.E. Doc. # Deblocking Filter 96, 98 G. Bjontegaard LBC-96-146 Intra Picture Predictive Coding 97 G. Bjontegaard LBC-96-147 GOB-Layer Syntax 85, 99, 116, 132 X. Ran LBC-96-145 Adaptive Arithmetic Coding 117 X. Ran via email Frame Size Quadrupler 118 X. Ran via email Variable Segmentation Coding 91, 98 J. Muller via email Motion Handling Basis 91 J. Nieweglowski via email Modulated Lapped Transform 84 R. Grinnell via email Back-Channel Error Resilience 87 T. Nakai via email 7. Conclusions The H.263+ video group is very pleased with its progress at this meeting. We wish to thank those who contributed to make this a very productive meeting, and to urge those who can contribute to our efforts to bring forth their ideas in our upcoming continuing activities. We believe we are on track toward delivering an enhanced video coding recommendation within our scheduled timeframe.