MPEG Video Software Statistics Gatherer
(Version 2.2; Feb 1, 1995)
Lawrence A. Rowe, Steve Smoot, Ketan Patel, and Brian Smith
Computer Science Division-EECS, Univ. of Calif. at Berkeley
This directory contains a public domain MPEG video statistics gatherer.
The decoder implements the standard described in the Committee
Draft ISO/IEC CD 11172 dated December 6, 1991 which is
sometimes referred to as "Paris Format." The code has been
compiled and tested on the following platforms:
HP PA-RISC (HP/UX 9.X) (i.e., HP 9000/7XX and 9000/3XX)
Sun Sparc (SunOS 4.X)
DECstation 5000 and Alpha
Sequent
Irix 4.0.5
Linux
See the CHANGES file for information on all the improvements over 2.0
See the manual page for information on how to use mpeg_stat.
Send bug reports to mpeg-bugs@plateau.cs.berkeley.edu,
job offers (PhD in '96) to smoot@cs.berkeley.edu ;-)
Vendors or other organizations interested in supporting
this research or discussing other aspects of this project should
contact Professor Larry Rowe at rowe@CS.Berkeley.EDU.
FUTURE PLANS:
In the next version I'd like to beef up the verification code and do
something with system layer audio (when present). In addition (major
though) MPEG-2 would be cool. If you send me code to do any of this, it
will be much appreciated. (In general, though, I'll only be improving it
to meet my thesis needs. -srs)
INSTALL:
If you have gcc, type "make"
See the file INSTALL for slightly more help.
AUDIO (we don't do audio, but Chad Fogg points out):
CCETT has been distributing executables only of their Audio bitstream
syntax verifier. The site address is: 161.105.2.22
Audio conformance bitstreams are also at ftp.tnt.uni-hannover.de
ACKNOWLEDGEMENTS:
We gratefully thank Hewlett-Packard, Fujitsu, the Semiconductor
Research Corporation for financial support.
We also want to thank the following people for their help:
Tom Lane of the Independent JPEG Group provided us with
the basic inverse DCT code used by our player.
(tom_lane@g.gp.cs.cmu.edu)
Reid Judd of Sun Microsystems provided advice and assistance.
Todd Brunhoff of NVR provided advice and assistance.
Toshihiko Kawai of Sony provided advice and assistance.
USAGE:
--------------------------------------------------------------------------------
As a sample of the basic information mpeg_stat collects, here is the output of:
mpeg_stat -quiet flower.mpg
mpeg_stat -- MPEG Analyzer for MPEG I video streams (version 2.2)
Reading flower.mpg
SUMMARY:
Total Bytes read: 719506. Total number of frames: 150. Length is 5.01 sec
Width: 352 Height: 240
Avg. Frame Size: 4786 bytes + 6 bits (average rate 1147692.76 bits/sec)
Total Compression Rate: 1.89 % of uncompressed 24 bit images
= 0.45 bits per pixel
Number of Macroblocks [width * height = sum]: 22 x 15 = 330 per frame
Skipped Macroblocks = 4389 (9.46%), Coded Macroblocks = 41992 (90.54%)
Coded blocks: 34.40% [ 22.30 22.79 23.44 24.21 4.89 2.37 ]
MPEG-Viewer requirements:
Pixel aspect ratio of 0.6735
Required display speed: 29.97 frames/sec
Specified bit rate is 1.00 MBits/sec (2500 * 400bits/sec)
Requested buffer size is 8K ints (16 bits/int).
And the constrained parameter flag is on.
The stream meets the constrained parameter requirements.
Length of vectors in half pixels:
Horizontal forward vectors, maximum : 39 average: 6
Vertical forward vectors, maximum : 22 average: 0
Horizontal backward vectors, maximum: 29 average: 5
Vertical backward vectors, maximum : 16 average: 0
Frame specific information:
10 I FRAMES, average is:
Size: 17323 bytes + 1 bits (24.13%)
Compression Rate: 6.84%
Q Factor [scales quantization matrix]: 12.51
40 P FRAMES, average is:
Size: 8031 bytes + 0 bits (44.74%)
Compression Rate: 3.17%
Q Factor [scales quantization matrix]: 12.55
100 B FRAMES, average is:
Size: 2235 bytes + 4 bits (31.13%)
Compression Rate: 0.88%
Q Factor [scales quantization matrix]: 16.49
50.59% interpolated Macro Blocks
