STANDARDS PIPELINE

Vol.32 No.1 February 1999

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ACM SIGGRAPH

Ongoing Standards Work Makes Great Strides

George S.Carson
GSC Associates, Inc.

February 99 Columns



George S.Carson

Imaging and Graphics Business Team

Previous columns have discussed the Imaging and Graphics Business Team (IGBT) of JTC 1. The team began operations in July and will complete its work in January 1999. Its final report has been prepared, and you can access it at their website.

In addition, the team’s website with all its documents will remain available indefinitely.

Organization

The IGBT held two public meetings, one in Orlando, FL, U.S.A. on July 26, 1998 and the second in Seoul, Republic of Korea on November 13, 1998. About 30 people attended the Orlando meeting, while in Seoul there was a meeting with key business leaders in the morning followed by a presentation to an audience of 360 people in the afternoon.

The leader of the IGBT was advised by a Steering Committee composed of managers and technologists with a strong interest in graphics and imaging. Team activities were divided into two focus areas: business and government and technology. The technology focus was further subdivided into four working groups:

• Synthetic environments
• Interaction
• Fundamental objects
• Archiving and distribution

Table 1. Participant Summary

The number of participants in each area is shown in Table 1. Based on those who took the time to fill in the registration information on the www site, 57 people from 13 countries signed up. Completing this information was not a requirement for participation as people were able to join each activity separately by adding themselves to the relevant email reflector.

Results Summary

The IGBT was successful in reaching and involving individuals and organizations outside the traditional participants in JTC 1 standards. It was also successful in attracting a diverse and balanced set of participants from industry, academia and government. The IGBT was successful in identifying several areas where new international standards might profitably be developed. The work of a more basic and longer term nature in the areas of interaction and fundamental objects was successfully initiated but could not be completed within the time constraints of the IGBT.

Publicity and Recruitment

The team’s activities were difficult to promote. In spite of a JTC 1 press release and over 200 direct contacts to media representatives, the team’s activities got little space in the press. The team was featured in articles in the ACM SIGGRAPH publication Computer Graphics and in a few other specialized publications. Most participants were recruited directly by team members or heard about the team through some standards-related organization. The large number of other ongoing ad hoc and consortia activities in the area of graphics and imaging contributed to the difficulty of attracting dedicated participants.

Methodology

The IGBT did not attempt to conduct any surveys, produce any taxonomies, collect and analyze any requirements or model any business processes. Such activities are an ongoing part of the business practices of the many firms and other organizations that contribute to the worldwide market for computer graphics and imaging technology, and the IGBT did not believe it necessary to attempt to duplicate this work. Instead, the team identified standards opportunities by seeking key areas with a substantial body of commercial practice that were at a point in the cycle of technology that international standardization might be beneficial. Synthetic environments and archiving/distribution were two such areas. The team also identified two other key areas — interaction and fundamental objects — where it felt there was a substantial body of diverse commercial practice that could benefit from the standardization process that aimed to coalesce needless diversity and improve interoperability.

Recommendations

The recommendations of the IGBT to JTC 1 were:

• The IGBT will conclude its activities by the end of January 1999 and does not ask to be continued.
• It is appropriate to adopt new computer graphics and imaging international standards to support the simulation and modeling community. One such area is standards to support modeling and exchange of synthetic environments. The Synthetic Environments Working Group expects to write a NP for this work before it concludes its work in late January 1999.
• Discussions concerning interaction and fundamental objects are on going, have been profitable and should continue in another forum. JTC 1/ SC 24 should be invited to transition these discussions into study groups.
• Discussions concerning archiving and distribution are on going and a further report and any recommendations will be made during the report at the JTC 1 plenary meeting.

Update on International Standards

SC 24: Computer Graphics

and Image Processing

The scope of SC 24 is the standardization of interfaces, in windowed and non-windowed environments, for computer graphics, image processing and the interaction with, and visual presentation of information. Between April 1998 and December 1998, SC 24 completed and submitted to ITTF three international standards for publication:

• ISO/IEC 14778, Presentation Environment for Multimedia Objects (PREMO). The four parts of this standard are Part 1: Fundamentals; Part 2: Foundation Component; Part 3: Multimedia Systems Services Component; Part 4: Modeling, Rendering, and Interaction Component.
• ISO/IEC 12087-5, Basic Image Interchange Format (a major new part to the International Standard for Image Processing and Interchange)
• ISO/IEC 9592-4/AM2, Programmer Hierarchical Interactive Graphics Systems (PHIGS) Language Bindings, Part 4: C

The current active work of SC 24 (website) includes these projects:

• Imaging and Graphic Business Team participation
• Portable network graphics (PNG)
• New parts and amendments to ISO/IEC 14772-1, VRML (VRML External Authoring Interface) and VRML Amendment 1)
• Corrigenda and new classes of registered items for ISO/IEC 9973, Procedures for the Registration of Graphical Items
• Amendment 1 to ISO/IEC 12087-2 (PIKS) to add a BIIF gateway

In addition, the following republication efforts are underway:

• Graphical Kernel System
• Programmer Hierarchical Interactive Graphics Systems (PHIGS)
• Programmer Hierarchical Interactive Graphics Systems (PHIGS) Language Bindings
• Computer Graphics Metafile for Transfer and Storage of Picture Description Information

PHIGS republication was recently completed. This was a major piece of work, folding in many amendments and making improvements in the quality of exposition in the standard. CGM now has several amendments as well as a number of defects and is in the process of being republished in a format that can be posted to the WWW. This is a large effort that is consuming significant resources.

The following work is now completed and inactive:

• GKS Language Bindings
• Interface Techniques for Dialogues with Graphical Devices (CGI)
• Conformance Testing
• Reference Model

SC 24 has significant planned future work from at least four sources. These sources are:

• The Web3D Consortium (formerly called the VRML Consortium), with whom SC 24 has a well-established and very productive cooperative relationship. This is expected to continue with standardizing VRML Next Generation as well as the specifications that result from the many active Web3D Working Groups.
• The WWW Consortium (W3C) with whom SC 24 is working on transposing PNG into an international standard, with plans for additional work that includes transposing the SMIL specification also. Other work includes WebCGM, a CGM profile developed in cooperation with the CGM Open Consortium, and SVG, an XML-coded, scalable vector graphics.
• The military, aerospace and defense community worldwide with whom SC 24 has demonstrated a recent success with the BIIF standard.
• The new CGM Open Consortium (website) with whom SC 24 is closely cooperating on the future of CGM (ISO/IEC 8632: SC 24 is using the experts of the CGM Open Consortium to review drafts of the CGM as revised and the WebCGM work in W3C.

Based on SC 24’s recent demonstrated successes with transposing VRML and BIIF into international standards, significant management level discussions with various government agencies are presently underway relating to future standards work based on proven technologies harvested for advanced and well proven military applications. The Imaging and Graphics Business Team has been the venue under which these opportunities have been explored and we presently anticipate that the following new work will come into SC 24 next year as a result of the efforts:

• Synthetic environments: A synthetic environment is a representation of a natural or artificial environment, whose components are located in reference to a well-defined spatial origin and coordinate system. The proven work of the SEDRIS (Synthetic Environment Data Representation & Interchange Specification) project is now expected to become the basis for a new class of standards in this area. For more information about SEDRIS, please consult their website.
• Real-time communications for graphics: In a distributed graphics system there is a need to exchange state information for real-time updates of presentations. The proven work of the Simulation Interoperability Standards Organization (SISO) may become the basis for a new class of standards in this area. For more information about SISO, please consult their website. Another candidate is the virtual reality transfer protocol (vrtp) which may the subject of a new Web3D Working Group.

Table 2. SC 24 Deliverables

SC 24 still feels that computer graphics, windowing and multimedia remain areas where much technology is still platform specific with an absence of major market factors that could force convergence to a single cross-platform solution. One reason is that all three of these technology areas are still major regions of platform differentiation where competitive advantages are sought rather than cooperation. Two platforms have the most significant market share within SC 24’s scope. One of these is the combination of UNIX on the various Silicon Graphics platforms. The second is Microsoft’s Win 32 on the PC and compatible platforms. A single vendor (in cooperation with its partners) controls each of these platforms. The value that SC 24 might add by transposing the computer graphics, windowing and multimedia elements of either platform into international standards is questionable.

SC 24 has identified one emerging platform of interest. This is a platform based on Open Source Software (notably the LINUX operating system). There may be opportunities for SC 24 to become a partner with the Open Source Software community to provide better graphics and imaging capabilities for such platforms. Finally, in the area of interchange formats for graphics and images there are many viable formats, both standard and non-standard. Again, there are no market factors (except for the business failure of a single vendor that supports particular format) that appear to be forcing convergence to a smaller number of formats.

Over the next nine months, SC 24 expects to complete the major deliverables listed in Table 2.

SC29: Coding of Audio, Picture, Multimedia and Hypermedia Information

The scope of SC 29 is the standardization of coded representation of audio, picture, multimedia and hypermedia information — and sets of compression and control functions for use with such information such as:

• Audio information
• Bi-level and limited bits-per-pixel still pictures
• Digital continuous-tone still pictures
• Computer graphic Images
• Moving pictures and associated audio
• Multimedia and hypermedia information for real-time final form interchange
• Audio visual interactive scriptware

SC 29 (website) feels that the trend towards digital terrestrial television broadcasting in the US using MPEG-2 will increase the prominence of digital television and digital image processing businesses thereby energizing related industries. SC 29 also believes that a “Next Generation Internet” (NGI) will emerge within three years. In the era of the NGI, they feel that rapid delivery of audio and visual content will be required for the continued growth of electronic commerce and applications such as tele-shopping, surveillance, tele-education, group-ware and electronic games. The hope is that all of these will demand high quality video, images and audio, and thus the audio and visual processing and compression technologies developed by SC 29 will be key.

The active work of SC 29 is described in the following subsections.

WG1: JPEG and JBIG

Working Group 1 is responsible for the JPEG (for coding of continuous-tone still images) and JBIG (for coding of bi-level images) standards development activities. The major effort of WG1 is presently devoted to the JPEG 2000 Image Coding System, originally scheduled for publication as a committee draft (CD) in November 1998, but now delayed to March 1999. JPEG-2000 is expected to deliver a new still image coding standard that has a functionality to provide a fine granularity for coded image quality by using a proportional amount of information. This coding standard will be the next generation of JPEG, which is widely used on the Internet and in digital cameras.

WG 11: MPEG

Working Group 11 is responsible for MPEG-2 (generic coding of moving picture and associated audio information) and MPEG-4 (coding of audio-visual objects). The major efforts of WG 11 are MPEG-4 version 1 which will shortly be published as a final draft international standard and MPEG-7 (multimedia content description interface) where work has just begun and a first working draft (WD) is expected in March 1999. MPEG-4 aims to establish universal, efficient coding of different forms of audio-visual objects of either natural or synthetic origin. SC 29 believes that the MPEG-4 standard will offer:

• A new kind of interactivity, with dynamic objects rather than only static ones
• Integration of natural and synthetic audio and visual material
• The possibility of influencing how audio-visual material is presented
• Reuse of both tools and data
• Relieve the application developer from concerns about communication details
• Simultaneous use of material coming from different sources and support of material going to different destinations
• Integration of real time and non-real time information in a single presentation

MPEG-4 addresses the needs of a wide range of applications in the areas of broadcasting, communications, electronic equipment and computer software. For example, new audio-visual distribution systems for emerging high-speed mobile environments require error resilience and object-based functionality for video and audio reproduction. Data retrieval by web browsers will be improved by real time 2D/3D scene generation with natural video accompanying audio and speech. Post-production applications that directly handle digitized audio and video objects will benefit from a new coding standard that enables direct manipulation of computer graphics and natural video.

Some expected applications of MPEG-4 are:

• Broadcast
• Collaborative scene visualization
• Content based storage and retrieval
• Digital AM broadcasting
• Digital television set-top box
• DVD
• Infotainment
• Mobile multimedia
• Real-time communications
• Streaming video on the Internet/intranet
• Studio and television post-production
• Surveillance
• Virtual meeting

The requirements that must be met by MPEG-4 to enable such applications include:

• Temporal random access
• High video quality (higher temporal and spatial resolutions)
• Interlaced and progressive scanning modes
• Improved coding efficiency
• Object-based functionality
• Text and graphics overlays
• Temporal and spatial synchronization of audio-visual objects
• Multiplexing audio-visual objects and other information data
• Temporal and spatial synchronization of distributed audio-visual objects
• Object-based coding flexibility by allowing all objects to be selectively coded
• Object-based spatial/temporal quality flexibility
• Object-based spatial/temporal scalability
• Object-based bitstream manipulating without the need for transcoding
• Compatibility with MPEG-2 standard
• Copy protection
• User interaction
• Downloading of audio-visual objects and other information data
• Multipoint operation
• Robustness to information error and loss
• Coding of multiple concurrent data streams
• Support of face animation parameters
• Synchronization
• Low end-to-end delay mode
• Interworking with other audio-visual systems
• User controls (e.g., sensitive regions)
• Stereoscopic views
• 3D Composition
• Face and body animation parameters (when virtual actors are used)
• Text to speech (TTS)
• Audio rendering

WG 12: MHEG

Working Group 12 is responsible for the MHEG (coding of multimedia and hypermedia information) standard and is currently work on defect correction and on an amendment for interoperability and conformance testing.

Expected Milestones

Over the next year, SC 29 expects to complete the major deliverables listed in Table 3.

Table 3. SC 29 Deliverables