ISO/IEC JTC 1/SC 29 N 2082
DATE: 1997-06-03
OUR REF.: 29CL388/29F060/29D144/


Coding of Audio, Picture, Multimedia and Hypermedia Information

Secretariat: Japan (JISC)

DOC. TYPE Referencing Explanatory Report
TITLE Referencing Explanatory Report (RFR) for ISO/IEC DIS 13522-6, Information technology -- Coding of multimedia and hypermedia information -- Part 6: Support for enhanced interactive applications
PROJECT NO. JTC (13522-6)
STATUS In accordance with Resolution 1 taken at the twenty-ninth SC 29/WG 12 meeting, 1997-04-14/18, Tokyo, Japan, the SC 29 Secretariat has submitted this report together with the DIS text, the disposition of comments report on CD, and copies of Reference Specifications (RSs) to the ISO/IEC ITTF for four-month DIS balloting.
REFERENCES SC 29 N 1605 (JTC 1 N 4046): The normative RS other than IS in JTC 1 ISs -- Guidelines for SCs
SC 29 N 1710: CD
SC 29 N 1889: Summary of Voting on CD
SC 29 N 2001: Resolutions, 9th SC 29 plenary meeting
SC 29 N 2062 (MHEG 97/N 1022): Resolutions, 29th WG 12 meeting
SC 29 N 2072 (MHEG 97/N 1025): Disposition of Comments Report on CD
SC 29 N 2081: DIS text
REQUESTED ACT. For SC 29's information
DISTRIBUTION P-, O- and L-members, ISO/IEC JTC 1/SC 29
Officers, ISO/IEC JTC 1/SC 29
Secretariat, ISO/IEC JTC 1

Narumi Hirose, Secretariat, ISO/IEC JTC 1/SC 29
IPSJ/ITSCJ*, Room 308-3, Kikai-Shinko-Kaikan Bldg., 3-5-8, Shiba-Koen, Minato-Ku Tokyo 105 Japan
Telephone: +81-3-3431-2808; Facsimile: +81-3-3431-6493;
Telex: 2425340 IPSJ J; E-mail:
* Information Processing Society of Japan/Information Technology Standards Commission of Japan (A standards organization accredited by JISC)

Dr. Jim Mitchell
Vice President, Technology and Architecture
JavaSoft, A Sun Microsystems, Inc. Business
2550 Garcia Avenue
Mountain View, California 94043-1100

30 May 1997

Ms Narumi Hirose,
Secretariat, ISO/IEC JTC 1/SC 29
IPSJ/ITSCJ Room 308-3,
Kikai-Shinko-Kaikan Bldg.
3-5-8 Shiba-Koen, Minato-ku
Tokyo 105 JAPAN
TP: +81-3-3431-2808
TF: +81-3-3431-6493

Dear Hirose-san,

We have reviewed your Referencing Explanatory Report (RER) that will accompany DIS Ballot Submission of ISO/IEC 13522-6. We approve of the content of your RER and agree to the referencing of our publicly available JavaTM specifications in ISO/IEC 13522-6.

We are pleased that SC29/WG12 has chosen to reference our Java specifications.


Dr. Jim Mitchell,
Vice President, Technology and Architecture
JavaSoft, A Sun Microsystems, Inc. Business

Referencing Explanatory Report
to accompany
DIS Ballot Submission of ISO/IEC 13522 - 6

Referenced Specifications

For submission
by: SC 29 (WG 12)

This Referencing Explanatory Report (RER) has been generated by SC 29/WG 12 to support the incorporation of the Java technology in ISO/IEC 13522-6, in accordance with the Guidelines of JTC 1 contained in the document JTC 1 N4046.

The Referenced Specification

The Referenced Specification (RS) to be included in ISO/IEC13522-6 comprises:

  1. the Java Virtual Machine (JVM) specification, version 1.02;
  2. the specific core packages: java.lang, and java.util., version 1.02.

These specifications are published in:

  1. Lindholm, Tim and Yellin, Frank (September 1996), The Java Virtual Machine Specification. ISBN: 0-201-63452-X, Addison-Wesley Publishing Co.: Reading, Massachusetts.
  2. Gosling, James, Yellin, Frank and The Java Team (May 1996), The JavaTM Application Programming Interface, Volume 1 Core Packages. ISBN: 0-201-633453-8, Addison-Wesley Publishing Co.: Reading, Massachusetts.


The requirement for the MHEG2 Standard to support extended processing of MHEG objects has been known for some time. As a consequence the MHEG Working Group (SC 29 WG 12) has had contact with Java experts from Sun Microsystems Inc. (SMI) over the past several years. In 1994 SMI was doing R&D work on a scripting language called "OAK" which later evolved into "Live-OAK" and then Java. At the time, WG 12 and experts from SMI attempted to find a way to collaborate in this effort. Nothing came of this as it was felt that development of a scripting language was beyond the scope of MHEG, and the concept of a virtual machine had not yet been clearly articulated and asserted. At that time Java was not a mature technology, and the copyright and other IPR issues could not be clearly identified. In addition, referencing of "non-standardised" specifications were not recognised as part of the JTC 1 procedures.

During 1995/96 work on MHEG-5 and 6 was proceeding rapidly, and once again requirements from the user community, especially DAVIC, were expressed for programming extensions for the MHEG object model. By this time Java was reaching maturity and other virtual machine technologies, such as byte code interpreters by Tao Systems and P-code compilers by Cabot Software, were either available or under development. Not knowing the extent of commercial work in the field, WG 12 did not wish to overlook the latest technology available. Hence, in February 1996 a Call for Proposals (CFP) to provide the virtual machine technology for those parts of MHEG-6 was issued.

Four responses to the CFP were received and evaluated by WG 12. The response by SMI, indicating that they could provide the Java technology, appeared to offer the best solution. In May 1996, work began within the WG to define the precise nature of the technical contribution that would be required by SMI to satisfy the MHEG-6 requirements.

MHEG VM Requirements and the Proposed Java Solution

From May 1996 to the present, integration of the Java technology with MHEG-6 as a solution has been carefully studied by WG12 and SMI experts.

The Java technology has evolved rapidly within the IT and Internet community during the past few years. Java has been developed under control of SMI by:

In response to the CFP, Java was offered to MHEG as an open specification that was available from their website. Until recently (late 1996) no official published versions of the specifications have been available. These specifications are now published by Addison-Wesley as the official SMI-sanctioned version of Java 1.02.

MHEG-6 extends the functionality of MHEG-5 by providing the specification for the MHEG-5 APIs and the necessary components of the Java environment to allow complex processing of multimedia hypermedia information, in a memory-safe and relatively efficient manner. The users of MHEG-5 have expressed the need for such a capability, especially for development of set-top boxes, near video-on-demand, distributed network games, and other highly interactive applications. To achieve this functionality, developers will implement MHEG-5 interchanged programme objects as Java byte code, which will be interpreted by the Java Virtual Machine (JVM). Using this technology provides the necessary inter-working, interoperability, and re-usability of MHEG objects.

The Java technology is well known, tested, widely implemented and stable. The developer community is large and growing rapidly. Most of the larger software providers have accepted the Java byte code as the target format for executable objects that are run in the WWW environment. Essentially they are supporting the Java philosophy in their own web browser technology. The Java technology is rapidly becoming a de facto standard for dynamic and interactive WWW applications.

Specific MHEG Java Requirements

MHEG-6 intends to reference the following components of the Java1.02 specifications:

The inter-working of Java and MHEG-5 is implemented in MHEG-6 by using an interchanged program object to provide the information for manipulating external program code. Using the "call" or "fork" actions, an MHEG-5 engine passes this code to the JVM where it is interpreted, processed, and the proper actions executed. In order to manipulate MHEG-5 objects from within Java program code, aniso.mheg5 (Java) package of the MHEG-5 APIs is provided. Theiso.mheg5 package maps MHEG-5 classes to Java interface classes; the actions applied to the classes are mapped to Java methods, which provide read and write access to the dynamic attributes of MHEG-5 objects.

Relationship of RS to Existing and Emerging Standards

The Java environment was developed in response to needs expressed by users of the Internet and specifically users of the WWW facilities. The Internet protocols have been used, tested, refined and extended since the 1980s. They are well-accepted de facto standards, recognised and used by industry, universities, and research organisations. The protocols and other features of the system are documented in a set of widely and freely available Request for Comments (RFCs).

Because Java is a complete multimedia hypermedia development toolkit and run-time system, it has many features that have some relationship to other ISO standards, but not exact counterparts in the ISO world.

Java offers many advanced features, such as thread management, class libraries, memory protection and a widely used byte code format that are desirable for inclusion in the Standard. Because of the broad acceptance of Java, it is important that MHEG-6 includes that technology, rather than re-invent a similar specification.

Market Acceptance of Proposed RS

Java development work is broad-based and widely accepted as the industry format for WWW implementations of program applets that are linked into web pages. The two leading web browser providers support the JVM and Java byte code. The Java technology is also well known, tested, widely implemented and stable, and is rapidly becoming a de facto standard for dynamic and interactive WWW applications. The JavaOne'97 Conference for application programmers attracted over 10,000 attendees.

An ancillary industry providing Java editing tools and programming environments exists and is growing rapidly. Java provides true cross-platform interoperability, via its concept of a virtual machine, which interprets non-machine specific byte code as the executable source of program objects. Most of the major IT competitors have licensed the Java product for their own use and are producing products that generate Java byte code.

Transposition Issues for RS

It would be very desirable to have Java in its totality transposed into an ISO standard, and SC 29/WG 12 has supported and worked with the JavaSoft management in the development of their PAS submitter application which is currently being balloted by JTC 1 NBs. It is the intention of WG 12 to continue to help and support the transposition of JavaSoft specifications into ISO standards. Because the transposition process could be lengthy and is time indeterminate, the WG needs to reference components of the specification in order to complete theMHEG-6 Standard with minimum delay. The JTC 1 SC29 approved schedule for completion of ISO/IEC 13522-6 is as follows:

Several potential developers of MHEG-6 applications, including the DAVIC consortium, have expressed the wish to see this Standard completed as quickly as possible. It is the feeling of WG 12 that the quickest way to do this is via the RS mechanism. If, at a future date, the specification is transposed, MHEG-6 can then be amended to reflect this new status of the Java reference.

Statements that address the Criteria for Evaluation of RS

The following statements are provided by SMI with respect to the criteria to be evaluated for a proposed RS as described in ISO/IEC JTC 1 N4046, Clause 6.3 Criteria.

6.3.1 Co-operative Stance

On initiative of the SC, the RS Originator shall provide or acknowledge a written statement that it agrees to the referencing of a specific document or family of documents in a JTC 1 standard. An applicable prior written statement may be used. Should the RS Originator decline to provide or acknowledge such a statement, the reference shall not be made.

SMI has along history of working openly and co-operatively with standards groups. In the JTC 1 arena SMI is active in several committees, including SC 22, SC 24, and SC 29, with respect to the Java technologies. For example, SMI has had an open dialog with SC 29/WG 12 that dates back to 1994 (when Java was a project code-named OAK). SMI is currently working with both SC 29 and SC 24 to allow them to include public references to the Java specifications in their emerging MHEG-6 (SC 29) and VRML 2.0 (SC 24)standards. SMI hosted the January 1997 joint SC 29/WG 12, SC 22/JavaStudy Group meeting at the JavaSoft facility in Cupertino, California and has been corresponding with the convener of the SC 22 Java Study Group. Ongoing Maintenance:

Who is responsible for maintenance of the RS if and when the need arises?

SMI is committed to evolving the Java platform in response to, and at a pace consistent with, market conditions. The only proviso is that the Java platform continues to remain compatible and interoperable across the widest possible set of hardware and operating systems.

To this end, SMI would provide all resources necessary for the ongoing maintenance, interpretation and enhancement of the Java platform. Changes:

What is the flexibility of the RS Originator to apply changes to the RS if so requested during the process of balloting the referencing standard?

The specifications and interface definitions of the Java platform have been adopted and implemented world wide by a broad spectrum of industry, government, and academia. SMI will therefore entertain technical changes that do not compromise existing and future compatibility and interoperability of Java across applications, implementations and platforms.

SMI expect that technical changes or additions, if any, will be kept to a minimum during balloting. This expectation is based on the existing high level of world-wide and cross-industry acceptance of, and dependence on, the current Java specifications and all publicly announced API additions prior to submission to the JTC 1 balloting process. Nevertheless, SMI is prepared to consider each case on its merits and, in principle, open to changes emanating from ISO/IEC JTC 1. Availability of the Referenced Specification

What is the status of public availability of the RS on fair, reasonable and non-discriminatory terms and conditions?

The RS is available from Addison-Wesley Publishing Company, "Series on Java" which contains the specifications to be referenced. These volumes are readily available from retail bookstores that handle IT-related texts, and are available on fair, reasonable and non-discriminatory terms and conditions.

Is the RS Originator willing to notify JTC 1 in a timely manner of any intention to terminate the availability of the RS?

SMI is willing to notify JTC 1 of any change in the status of the availability of the RS.

6.3.2 Intellectual Property Rights

It is the SC's responsibility to ensure that statements in response to - are provided in the RER. The RS Originator is requested, in the strongest terms, to make known in writing its position on the items listed below. Patents:

What is the status of meeting the ISO/IEC policy on patent matters?

SMI is (and has been) compliant with the ISO/IEC Patent Policy. Copyrights:

What copyrights exist, and what copyrights is the RS Originator willing to grant, throughout both the evaluation and the publication cycle?

In general, document copyrights remain with SMI and extend to all media in which the information may be embodied. However, SMI will not require any copyright fees for documents accepted by ISO/IEC JTC 1, or its national bodies, for standardization. Trademark Rights:

What trademarks apply to the RS and with what conditions?

SMI owns a number of trademarks with respect to its Java technologies. These trademarks include, but are not limited to, the names "Java", "Java Compatible", "100% Pure Java", and the internationally recognized "cup and steam" logo.

These trademarks are used to represent that a given implementation of Java meets the strict compatibility and interoperability criteria inherent in the Java platform specifications. SMI expects to continue to own all of its trademark logos and names and would not expect to transfer the rights associated with them to ISO/IEC.

6.3.3 Quality

The SC shall establish that the proposed RS is of adequate quality, considering topics such as the length of the time the specification has existed, whether products have been implemented using it, whether conformance requirements are clear, and whether the specification is readily and widely available.

The specifications being referenced by MHEG-6 have evolved over a period of at least three years. It is a well-written technical specification, which has been recently professionally edited by one of the more popular technical textbook publishers. It is read and used by a wide range of students, academics, business, and professional programmers.

Most computer book stores keep in stock a larger number of Java related texts than any other single topic in the discipline. The Java programming language itself is now being taught in computer science departments throughout the world.

SMI impose reasonable but stringent conditions on potential developers of Java conforming systems.

1 Java is a Trademark of Sun Microsystems Inc.

2 MHEG refers to WG 12 and also to the ISO/IEC 13522 suite of standards; i.e. MHEG -n refers to part "n" of the standard: ISO/IEC 13522 - n.