1
2 MPEG-1 Video Software Encoder
3 (Version 1.5; February 1, 1995)
4
5 Lawrence A. Rowe, Kevin Gong, Eugene Hung, Ketan Patel, Steve Smoot
6 and Dan Wallach
7 Computer Science Division-EECS, Univ. of Calif. at Berkeley
8
9This directory contains the freely distributed Berkeley MPEG-1 Video
10Encoder. The encoder implements the standard described in the ISO/IEC
11International Standard 11172-2. The code has been compiled and tested
12on the following platforms:
13
14 DECstation 5000 and Alpha
15 HP PA-RISC (HP/UX 9.X) (i.e., HP 9000/7XX and 9000/3XX)
16 SGI Indigo running IRIX 5.0.1
17 Sun Sparc (SunOS 4.X)
18
19In addition, Rainer Menes from the Technical University of Munich has
20ported the encoder and decoder to the Macintosh. You can get that code
21directly from him (menes@statistik.tu-muenchen.de), or from the
22Berkeley FTP archive (mm-ftp.CS.Berkeley.EDU). If you decide to port
23the code to a new architecture, please let us know so that we can
24incorporate the changes into our sources.
25
26This directory contains everything required to build the encoder
27and run it. We have included source code, makefiles, binaries
28for selected platforms, documentation, and test data. Installation
29instructions are given in the file named src/mpeg_encode/INSTALL. A man
30page is given in the file doc/mpeg_encode.1. A detailed user
31manual is provided in postscript format in the file doc/user-manual.ps.
32
33The encoder will accept any input file format as long as you provide
34a script to convert the images to PPM, YUV, JPEG, or JMOVIE format. Input
35file processing is described in the file doc/INPUT.FORMAT. Options to
36control input file processing and compression parameters are specified in
37a parameter file. Very little error processing is done when reading
38this file. We suggest you start with the sample parameter file
39examples/template.param and modify it. See also examples/default.param.
40
41The convert directory of Mpeg-Tools contains utilities you might find
42useful including:
43
44programs to do PPM/YUV conversion and programs to convert Parallax
45XVideo JPEG files into PPM, YUV, or JPEG frames.
46
47The motion vector search window can be specified, including half-pixel
48block matching, in the parameter file. We have implemented several
49search algorithms for P-frames including: 1) exhaustive search,
502) subsampled search, and 3) logarithmic search. We have also implemented
51several alternatives for B-frame block matching including: 1) interpolate
52best forward and best backward block, 2) find backward block for best
53forward or vice-versa (called CROSS2), and 3) exhaustive cross product
54(i.e., go out for coffee and a donut!). The search algorithms are controlled
55by options in the parameters file. For tips on choosing the right search
56technique, see the user manual.
57
58The encoder can be run on one computer (i.e., sequential) or on several
59computers (i.e., parallel). Our goal is to produce a portable, easy-to-use
60encoder that we can use to encode large volumes of video material for
61the Berkeley VOD system (see paper VodsProp93.ps.Z on the FTP archive).
62The parallelism is done on a sequence of pictures. In other words, you
63can spawn one or more children to encode continuous runs pictures. The
64uncompressed data can be accessed either through NFS or TCP sockets.
65The goal is to allow you to encode using multiple processors, think
66spare cycles on workstations, to speed up the encoding time. Although
67performance depends on the speed of individual processors, the file system
68and network, and the P/B frame search methods, we have encoded 3.75
69frames/second on 8 HP Snakes running in parallel as compared with 0.6
70frames/second on 1 Snake. These are preliminary results. We are continuing
71to experiment with and tune the code. Instructions to run the parallel system
72are given in the man page and the parallel.param example parameter file.
73
74We have done some tuning to produce a reasonable encoder, but there are
75many more optimizations that we would like to incorporate. These
76extensions are listed in the file doc/EXTENSIONS. If you succeed in
77implementing any of them, please let us know!
78
79Send bug reports to:
80
81mpeg-bugs@CS.Berkeley.EDU
82 Problems, questions, or patches should be sent to this address.
83
84Anyone interested in providing financial support for this research or
85discussing other aspects of this project should contact Larry Rowe at
86Rowe@CS.Berkeley.EDU (+1 510-642-5117).
87
88This software is freely distributed. That means, you may use it for
89any non-commercial purpose. However, patents are held by several companies
90on various aspects of the MPEG video standard. Companies or individuals
91who want to develop commercial products that include this code must
92acquire licenses from these companies. For information on licensing, see
93Appendix F in the standard.
94
95ACKNOWLEDGEMENTS:
96
97We gratefully thank Hewlett-Packard and Fujitsu who provided financial
98support for this work. We also want to thank the following people and
99organizations for their help:
100
101 Jef Poskanzer who developed the pbmplus package.
102 ---------
103 Copyright (C) 1989, 1991 by Jef Poskanzer.
104
105 Permission to use, copy, modify, and distribute this software and its
106 documentation for any purpose and without fee is hereby granted, provided
107 that the above copyright notice appear in all copies and that both that
108 copyright notice and this permission notice appear in supporting
109 documentation. This software is provided "as is" without express or
110 implied warranty.
111 ---------
112
113 Eiichi Kowashi of Intel and Avideh Zakhor of U.C. Berkeley who
114 provided valuable suggestions on motion vector searching.
115
116 Chad Fogg of the University of Washington who has helped us
117 understand many issues in MPEG coding and decoding.
118
119 Rainer Menes of the Technical University of Munich who has ported the
120 the Berkeley MPEG encoder and decoder to the Macintosh, and he has
121 provided us with many suggestions to improve the code.
122
123 Robert Safranek of ATT for comments, suggestions, and most of the
124 code for custom quantization tables.
125
126 Jim Boucher of Boston University for jmovie2jpeg.
127
128 The San Diego SuperComputing Center for providing facilities to
129 develop some of the code contained within.
130