INTERNATIONAL ORGANISATION FOR STANDARDISATION
ORGANISATION INTERNATIONALE DE NORMALISATION
ISO/IEC JTC1/SC29/WG11
CODING OF MOVING PICTURES AND AUDIO

ISO/IEC JTC1/SC29/WG11 N1905
October 1997 / Fribourg


MPEG-4 Reference Software
(Committee Draft 14496-5)


This web page is intended to provide an overview of the audio-related sections in the "MPEG-4 Reference Software Committee Draft 14496-5" and is based on excerpts from this document. The complete document including the audio-related software is available by ftp.


Introduction

This part of the MPEG-4 Committee Draft contains simulation software for tools defined in parts 1, 2, 3 and 6 of the standard. This software has been derived from verification models used in the process of developing the standard. Due to the delay between acceptance of a tool and its availability in source code form, the source for some tools described in other parts of this Committee Draft may not be present.

Where bitstream encoding software is provided, attention is called to the fact that these encoders are provided for the purpose of creating bitstreams with normative syntax. The performance of these encoders should not be taken as indicative of that which can be obtained from implementations where quality and computational optimization are given priority. The techniques used for encoding are not specified by this Committee Draft.

Copyright disclaimer for software modules

WG11 adopts the following text of copyright disclaimer to be attached to software modules donated to ISO/IEC according to resolution 13 of the Chicago meeting. In the text <MPEG standard> should be replaced with the appropriate standard, e.g. MPEG-2 AAC (ISO/IEC 13818-7), MPEG-4 System (ISO/IEC 14496-1), MPEG-4 Video (ISO/IEC 14496-2), MPEG-4 Audio (ISO/IEC 14496-3).

"This software module was originally developed by <FN1> <LN1> (<CN1>) and edited by <FN2> <LN2> (<CN2>), <FN3> <LN3> (<CN3>), … in the course of development of the <MPEG standard>. This software module is an implementation of a part of one or more <MPEG standard> tools as specified by the <MPEG standard>. ISO/IEC gives users of the <MPEG standard> free license to this software module or modifications thereof for use in hardware or software products claiming conformance to the <MPEG standard>. Those intending to use this software module in hardware or software products are advised that its use may infringe existing patents. The original developer of this software module and his/her company, the subsequent editors and their companies, and ISO/IEC have no liability for use of this software module or modifications thereof in an implementation. Copyright is not released for non <MPEG standard> conforming products. CN1 retains full right to use the code for his/her own purpose, assign or donate the code to a third party and to inhibit third parties from using the code for non <MPEG standard> conforming products. This copyright notice must be included in all copies or derivative works. Copyright 199_”.

<FN>=First Name, <LN>=Last Name, <CN>=Company Name

Audio reference software

Natural audio

Location Notes
Audio/Natural/refsoft971120.tgz Encoder and decoder for natural audio elementary streams

Structured audio

Location Notes
Audio/SNHC/sa.tgz Encoder and decoder for structured audio

Text to speech interface

Location Notes
Audio/SNHC/tts_source.zip Text to speech encoder and decoder

Visual reference software

[This section of CD14496-5 is not included here.]

Systems reference software

[This section of CD14496-5 is not included here.]


Annex A (informative)

Additional utility software

Software that appears in this Annex has proven to be useful to the developers of the standard but is not a normative reference implementation.

Audio utility software

Text to speech data and driver Code

Location Notes
Audio/SNHC/tts_execute.zip TTS demo program
Audio/SNHC/tts_db.zip Korean language speech data used by demo program

Visual utility software

[This section of CD14496-5 is not included here.]

Systems utility software

[This section of CD14496-5 is not included here.]


Annex B (informative)

Providers of reference software

The following organizations have contributed software referenced in this part of the Committee Draft:




Contents of N1905

[The visual- and systems-related software in CD14496-5 is not included here.]

Location Notes
w1905.pdf The complete document N1905 (without the software itself)
README_external_files.txt Information about external modules used by this software
Audio/Natural/refsoft971120.tgz Encoder and decoder for natural audio elementary streams
Audio/Natural/README_refsoft Information about natural audio software
Audio/SNHC/sa.tgz Encoder and decoder for structured audio
Audio/SNHC/sa_bitstreams.zip Example bitstreams for structured audio
Audio/SNHC/tts_source.zip Text to speech encoder and decoder
Audio/SNHC/Readme_tts.txt Information about text to speech software
Audio/SNHC/tts_execute.zip TTS demo program
Audio/SNHC/tts_db.zip Korean language speech data used by demo program

The AFsp Audio File I/O Package

To provide support for a variety of audio file formats, the natural audio reference software uses the AFsp package for all audio file i/o. The AFsp package is written by Peter Kabal and is available via ftp:

current version: AFsp-V3R2.tar.Z
WWW site: http://www.TSP.EE.McGill.CA/software.html
ftp site: ftp://ftp.TSP.EE.McGill.CA/pub/AFsp
mirror site: ftp://ftp.tnt.uni-hannover.de/pub/audio/AFsp


Important Excerpt from the MPEG Audio FAQ

Under what circumstances can I use MPEG-4 FCD reference software?

First, it should be understood that this software has the goal of describing and explaining the MPEG-4 standard.

The decoder software accurately implements one method of decoding MPEG-4 bit-streams. In this sense it is normative. However, there are other ways of correctly decoding MPEG-4 bit-streams. As long as the resulting difference in output from the output signal generated by this reference software is not larger than the limits set in the conformance part of the MPEG-4 standard, these other methods are also considered compliant decoders.

For the encoder, the purpose of this software is purely informative. It describes one example of possible encoding software producing bitstreams which comply to the MPEG-4 standard. This software is not optimized, neither in the speed of execution nor in the quality of the output signal. For some of the algorithms the picture or sound quality is similar to what is possible according to state-of-the-art encoding For other algorithms, (like the AAC t/f-encoding of audio signals) the encoder is just an illustration of techniques to be used and delivers an output quality far below the one which has been demonstrated in verification tests of MPEG-4.

The following copyright disclaimer is attached to the software modules in the reference software:

"This software module was originally developed by <FN1> <LN1> (<CN1>) and edited by <FN2> <LN2> (<CN2>), <FN3> <LN3> (<CN3>), … in the course of development of the <MPEG standard>. This software module is an implementation of a part of one or more <MPEG standard> tools as specified by the <MPEG standard>. ISO/IEC gives users of the <MPEG standard> free license to this software module or modifications thereof for use in hardware or software products claiming conformance to the <MPEG standard>. Those intending to use this software module in hardware or software products are advised that its use may infringe existing patents. The original developer of this software module and his/her company, the subsequent editors and their companies, and ISO/IEC have no liability for use of this software module or modifications thereof in an implementation. Copyright is not released for non <MPEG standard> conforming products. CN1 retains full right to use the code for his/her own purpose, assign or donate the code to a third party and to inhibit third parties from using the code for non <MPEG standard> conforming products. This copyright notice must be included in all copies or derivative works. Copyright 199_".

In the text <MPEG standard> should be replaced with the appropriate standard, e.g. MPEG-2 AAC (ISO/IEC 13818-7), MPEG-4 System (ISO/IEC 14496-1), MPEG-4 Video (ISO/IEC 14496-2), MPEG-4 Audio (ISO/IEC 14496-3). <FN> should be replaced by First Name, <LN> by Last Name, and <CN> by Company Name.


(MPEG Audio Web Page) (Tree) (Up)

Heiko Purnhagen 25-Aug-1998