1Pammixmulti User Manual(0)                          Pammixmulti User Manual(0)
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NAME

6       pammixmulti - blend together multiple PAM images
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SYNOPSIS

11       pammixmulti
12         [--blend=average|random|mask]
13         [--maskfile=filename]
14         [--stdev=number]
15         [--randomseed integer]
16         filename ...
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18       Minimum  unique  abbreviation of an option is acceptable. You can use a
19       single hyphen instead of double hyphens to denote options. You can  use
20       white space in place of the equals sign to separate an option name from
21       its value.
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DESCRIPTION

26       This file is part of Netpbm(1).
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28       pammixmulti mixes two or more images to produce a new image.  The  pro‐
29       gram provides multiple ways to interpret "mix."
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OPTIONS

34       In  addition  to  the options common to all programs based on libnetpbm
35       (most notably -quiet, see
36        Common Options ⟨index.html#commonoptions⟩  ),  pammixmulti  recognizes
37       the following command line options:
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41       --blend=average|random|mask
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43              This  option  specifies  how the input images should be mixed to
44              produce the output image.  With --blend=average  (the  default),
45              each  pixel  in  the  output is produced by averaging the corre‐
46              sponding pixels from all the input images.  With --blend=random,
47              each  pixel  in  the  output is produced by selecting the corre‐
48              sponding pixel from one of the input images, chosen at random on
49              a  per-pixel basis.  With --blend=mask, each pixel in the output
50              is produced by a weighted average of  the  corresponding  pixels
51              from all the input images based on the grayscale level of an ad‐
52              ditional mask image.
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56       --maskfile=filename
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58              In conjunction with --blend=mask, this option names a  grayscale
59              mask  file  to control the blending of each pixel.  (If the file
60              is not grayscale, the first channel is treated as gray).   Where
61              the  mask  file is black, the first image is selected. Where the
62              mask file is white, the last image  is  selected.   Intermediate
63              levels of gray select intermediate images.
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67       --stdev=number
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69              When  used  with --blend=mask, this option controls how smoothly
70              the various input images are mixed to produce each output pixel.
71              For  example,  consider running pammixmulti with three input im‐
72              ages and a mask image that uses gray levels from 0 to 255. Given
73              --stdev=0.0,  gray levels 0-84 produce exclusively image 1; gray
74              levels 85-170 produce  exclusively  image  2;  and  gray  levels
75              171-255 produce exclusively image 3.  If the argument to --stdev
76              is positive, images are blended according to a normal  distribu‐
77              tion.  Hence, gray levels around 85 produce an output pixel that
78              includes roughly equal amounts of the corresponding  pixel  from
79              images 1 and 2 but less of the corresponding pixel from image 3.
80              As number tends towards the number of input images (going beyond
81              that has diminishing impact), the output tends to look more like
82              --blend=average. number defaults to 0.25.
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86       --randomseed integer
87              This is the seed for  the  random  number  generator  used  with
88              --blend=random
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90              Use  this  to  ensure you get the same image on separate invoca‐
91              tions.
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ARGUMENTS

97       You supply the names of the files to mix as non-option arguments.
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EXAMPLES

102       Average a bunch of PPM images to produce a new PAM image:
103           pammixmulti input*.ppm >output.ppm
104       </pre>
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106       Mix these same images by taking each pixel from a randomly selected input
107       image:
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109           pammixmulti --blend=random input*.ppm >output.ppm
110       </pre>
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112       Use a mask image to control the fading among input images on a
113       pixel-by-pixel basis:
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115           pammixmulti --blend=mask --maskfile=mask.pgm >output.pam \
116              one.pam two.pam three.pam four.pam
117       </pre>
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119       Do the same but with more abrupt transitions:
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121           pammixmulti --blend=mask --maskfile=mask.pgm --stdev=0.0 >output.pam \
122              one.pam two.pam three.pam four.pam
123       </pre>
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125       and now with more gradual transitions:
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127           pammixmulti --blend=mask --maskfile=mask.pgm --stdev=1.0 >output.pam \
128              one.pam two.pam three.pam four.pam
129       </pre>
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HISTORY

134       pammixmulti was new in Netpbm 10.85 (December 2018).
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AUTHOR

139       Copyright 2018 Scott Pakin, scott+pbm@pakin.org.
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SEE ALSO

143       pamcomp(1), ppmmix(1), pamarith(1), pnm(1), pam(1)
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Table Of Contents

148       •
149
150              SYNOPSIS ⟨#synopsis⟩
151
152       •
153
154              DESCRIPTION ⟨#description⟩
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156       •
157
158              OPTIONS ⟨#options⟩
159
160       •
161
162              ARGUMENTS ⟨#arguments⟩
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164       •
165
166              EXAMPLES ⟨#examples⟩
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168       •
169
170              HISTORY ⟨#history⟩
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172       •
173
174              AUTHOR ⟨#author⟩
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176       •
177
178              SEE ALSO ⟨#seealso⟩
179

DOCUMENT SOURCE

181       This manual page was generated by the Netpbm tool 'makeman'  from  HTML
182       source.  The master documentation is at
183
184              http://netpbm.sourceforge.net/doc/pammixmulti.html
185
186netpbm documentation           18 November 2018     Pammixmulti User Manual(0)