comparison Meerwald-dir/cmp_ppm.1 @ 24:9f20bce6184e v0.7

move directories, support netpbm 11
author Peter Meerwald-Stadler <pmeerw@pmeerw.net>
date Fri, 20 Dec 2024 13:08:59 +0100
parents Meerwald/cmp_ppm.1@be303a3f5ea8
children
comparison
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23:71dd4b96221b 24:9f20bce6184e
1 .\"
2 .\" cmp_ppm.1 - the *roff document processor man page source
3 .\"
4 .TH cmp_ppm 1 "98/07/08" "Watermarking, Version 1.0"
5 .SH NAME
6 cmp_ppm \- a program to create the difference image of two PGM images
7 .SH SYNOPSIS
8 .B cmp_ppm
9 [
10 .BI \-c \ name
11 ]
12 [
13 .B \-h
14 ]
15 [
16 .BI \-m \ number
17 ]
18 [
19 .BI \-o \ ofile
20 ]
21 .BI \-i \ ifile
22 .I file
23 .SH DESCRIPTION
24 .B cmp_ppm
25 is a program to create the difference image of two PPM (portable pixmap)
26 RGB color images. To compare PGM (portable graymap) grayscale images, use
27 the
28 .B cmp_pgm
29 program.
30 .PP
31 The color components to compare are specified with the
32 .BI \-c \ name
33 option, where
34 .I name
35 is one of the following:
36 .TP
37 .B red
38 The red color component.
39 .TP
40 .B green
41 The green color component.
42 .TP
43 .B blue
44 The blue color component.
45 .PP
46 Multiple color components are allowed. Specifying only the inital letter
47 of a color component is sufficient.
48 Per default
49 .B cmp_ppm
50 compares the luminance value of the images. This operation may be
51 selected explicitly with the
52 .BI \-c \ luminance
53 option.
54 .PP
55 If
56 .I file
57 or
58 .I ofile
59 is not specified, then standard input or standard output is
60 used.
61 .PP
62 .SH OPTIONS
63 .TP
64 .BI \-c \ name
65 Specifies color component(s) or luminance to compare. Default: luminance.
66 .TP
67 .B \-h
68 Print a help message.
69 .TP
70 .BI \-i \ ifile
71 The original image. Mandatory.
72 .TP
73 .BI \-m \ number
74 Multiplication factor to magnify differences between the to
75 original and input image.
76 Default value: 16.
77 .TP
78 .BI \-o \ ofile
79 Output image file to contain the difference image in PPM format.
80 .TP
81 .I file
82 Input image that is compared against
83 .I ifile.
84 Default: standard input.
85 .SH OUTPUT
86 The difference image in PPM format is written to standard output or,
87 optionally, to
88 .I ofile.
89 .SH AUTHOR
90 Peter Meerwald.
91 Email bug reports to pmeerw@cosy.sbg.ac.at.
92 .SH AVAILABILITY
93 The most recent released version of
94 .B cmp_ppm
95 is always available
96 at http://www.cosy.sbg.ac.at/~pmeerw/Watermarking or via anonymous ftp from ftp.cosy.sbg.ac.at in the
97 directory /pub/people/pmeerw/Watermarking.
98 .SH "SEE ALSO"
99 .B cmp_ppm
100 (1)

Repositories maintained by Peter Meerwald, pmeerw@pmeerw.net.