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mpeg2encode / mpeg2decode
=========================
MPEG-2 Encoder / Decoder, Version 1.1, June 1994
MPEG Software Simulation Group
(MPEG-L@netcom.com)
Contents:
1. Overview
2. Introduction
3. Contacting the MPEG Software Simulation Group
4. Availability
5. Installation
6. Acknowledgements
7. History of the technical report
1. Overview
===========
This directory contains our implementation of an ISO/IEC DIS 13818-2 codec.
It converts uncompressed video frames into MPEG-1 and MPEG-2 video
coded bitstream sequences, and vice versa.
The files mpeg2enc.doc and mpeg2dec.doc in the doc/ directory contain
further information about the codec. The doc directory also contains an
FAQ file answering frequently asked questions about MPEG. A precompiled
version of the programs for MSDOS (requires at least a '386) and a set
of verification files are available separately.
Subdirectories src/mpeg2enc and src/mpeg2dec contain the source code
for the encoder and decoder, subdirectory par/ contains a couple of
example encoder parameter files for 25 and 30 frames/sec MPEG-2 and
MPEG-1 video.
2. Introduction
===============
MPEG-2 Video is a generic method for compressed representation of video
sequences using a common coding syntax defined in the document ISO/IEC
13818 Part 2 (CD: Nov. 1993, DIS: March 1994) by the International
Organization for Standardization (ISO) and the International
Electrotechnical Commission (IEC), in collaboration with the
International Telecommunications Union (ITU) as Recommendation H.262.
The MPEG-2 concept is similar to MPEG-1, but includes extensions to
cover a wider range of applications. The primary application targeted
during the MPEG-2 definition process was the all-digital transmission
of broadcast TV quality video at coded bitrates between 4 and 9
Mbit/sec. However, the MPEG-2 syntax has been found to be efficient
for other applications such as those at higher bit rates and sample
rates (e.g. HDTV). The most significant enhancement over MPEG-1 is the
addition of syntax for efficient coding of interlaced video (e.g. 16x8
block size motion compensation, Dual Prime, et al). Several other more
subtle enhancements (e.g. 10-bit DCT DC precision, non-linear
quantization, VLC tables, improved mismatch control) are included
which have a noticeable improvement on coding efficiency, even for
progressive video. Other key features of MPEG-2 are the scalable
extensions which permit the division of a continuous video signal into
two or more coded bit streams representing the video at different
resolutions, picture quality (i.e. SNR), or picture rates.
The MPEG Software Simulation Group is currently developing MPEG
software with the purpose of providing aid in understanding the various
algorithms which comprise an encoder and decoder, and giving a sample
implementation based on advanced encoding models. The MPEG-2 software
project is an on-going development. Since the current version of the
encoder already employs a reasonable (and the most popular) subset of
the MPEG-2 signal coding toolkit, and there appears to be sufficient
public interest, we have decided to make a public release of the code.
The encoder can also be used for generating good quality constant
bitrate MPEG-1 sequences and is (to our knowledge) the first publicly
available encoder based on the relatively sophisticated TM5 coding model.
3. Contacting the MPEG Software Simulation Group
================================================
We welcome any project-specific questions, comments, suggestions, bug
reports etc. They should be sent to the Internet E-mail address:
MPEG-L@netcom.com
which automatically forwards them to the authors.
Additionally, if you wish to be added to the general discussion
and annoucement list (mpeg-users@netcom.com), send mail to:
listserv@netcom.com
with the following line in the message body:
subscribe mpeg-users [your E-mail address]
4. Availability
===============
The most recent version of the codec source code is available by anonymous
ftp from:
ftp.netcom.com:/pub/cfogg/mpeg2
The Internet address of ftp.netcom.com is [192.100.81.1].
The directory contains the following files:
README this file
mpeg2codec_v1.1.tar.gz codec source code and documentation
mpeg2codec_verify_v1.1.tar.gz verification archive
mpeg2d11.zip MS-DOS executable archive
mpeg2w11.zip Win32s executable archive
tennis.m2v sample MPEG-2 video sequence (8 frames 704x576)
tennis.par, tennis.stat.gz parameter file and statistics output
for tennis.m2v
You need gunzip (GNU zip/unzip) to uncompress the .gz archives.
Alternatively, the files may be retrieved by sending E-mail to:
ftp-request@netcom.com
... with the following line in the body of the message:
SEND cfogg/mpeg2/mpeg2codec_v1.1.tar.gz
You can retrieve the directory listings by sending the following command
to ftp-request@netcom.com:
DIR cfogg/mpeg2
General information can be retrieved with the command: HELP
World Wide Web:
A set of WWW pages describing the project and containing information
about the latest versions and their availability will be announced soon.
This will include a couple of sample MPEG-2 video bitstreams.
5. Installation
===============
mpeg2decode and mpeg2encode have been compiled and tested on the following
platforms:
- SUN SPARCstation 10, SunOS 4.1.3, cc / gcc / acc
- '386-PC, MSDOS 5.0, djgpp v1.11, gcc v2.5.7
The source code should compile without major modifications on other 32 bit
systems using both K&R and ANSI C compilers. Systems with 16 bit 'int'
variables or segmented memory models are not supported.
Please report any modifications you had to apply in order to install the
programs on your system to the address MPEG-L@netcom.com.
The encoder and decoder are kept in separate sub-directories,
src/mpeg2dec contains the decoder, while src/mpeg2enc contains the
encoder sources. The following installation procedure applies to both
the encoder and the decoder:
Step 1: edit Makefile
---------------------
You may have to set CC to your C compiler and CFLAGS to the flags required
by the compiler. It is sufficient to set these variables in the top directory
Makefile. They are propagated to the individual Makefiles of the encoder
and decoder. Any other changes have to be applied to the individual Makefiles,
however.
You can compile the decoder with or without X11 output. Please follow the
instructions in the top-level Makefile to activate X Window System support.
If you use a C compiler which doesn't understand ANSI-C function prototypes
add -DNON_ANSI_COMPILER to CFLAGS.
Step 2: edit src/mpeg2dec/config.h
----------------------------------
In most cases, no modification should be required. If your C library
doesn't accept "rb" / "wb" parameters in fopen() (required to disable
LF <-> CR/LF conversion on MSDOS systems), change the #defines RB and WB
to "r" and "w".
Step 3: make
------------
Type 'make' from the top directory (mpeg2). On a PC with DJGPP installed you
have to enter 'make pc' in the individual source directories to produce
.exe files.
Step 4: verification
--------------------
If you have downloaded and unarchived the mpeg/verify directory, you can
verify correct compilation of the codec by typing 'make test'. No differences
should be reported. The only comparison which is allowed to fail is between
test.m2v and new.m2v, caused by floating point accuracy dependencies in the
forward DCT.
6. Acknowledgements
===================
Authors of the current release are:
Stefan Eckart (stefan@lis.e-technik.tu-muenchen.de)
Chad Fogg (cfogg@netcom.com)
Cheung Auyeung (auyeung@mot.com)
Sorin Papuc (sop@compcore.com)
Special thanks are due to
J. Steurer, M. Oepen, IRT (Institut fuer Rundfunktechnik, Muenchen):
for contributing motion estimation speed improvements (distance
computation short-circuit in conjunction with spiral search, cf.
dist1(), fullsearch())
Numerous users:
for providing bug reports and Makefiles
7. History of Technical Report Project
======================================
The Technical Report, a document which primarily consists of
a C source code program, was initiated by the MPEG committee to:
- Provide an example of MPEG video syntax being intelligently employed
to generate good quality video.
- A reference tool for implementors
- Aid in understanding the MPEG specification
MPEG would like to especially thank Dr. Stefan Eckart for his
contributions have greatly helped the MPEG-2 Technical Report project
start onto a successful path towards the final 13818-5 document.
MPEG lends a kind acknowledgement to Arian Koster (PTT) for initiating
the MPEG-1 technical report project in Autumn 1992, and Leonardo
Chiariglione (Convenor of MPEG) and Didier Le Gall (Chairman of MPEG
Video) for support throughout both projects. Also many thanks to
MPEG-1 project contributors Peter Au (Hughes Aircraft), Ron Burns
(Hughes Aircraft), Stefan Eckart (Technical University of Munich), Chad
Fogg (Cascade Design Automation / Xenon Microsystems), Tsuyoshi
Hanamura (Waseda University), Kinya Oosa (Nippon Steel), Brian Quandt
(Heuris Logic) and Hiroshi Watanabe (NTT).
----
End of Readme file