1Pammixmulti User Manual(0)                          Pammixmulti User Manual(0)
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5       " "netpbm documentation"
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NAME

11       pammixmulti - blend together multiple PAM images
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SYNOPSIS

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

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

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

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

107       Average a bunch of PPM images to produce a new PAM image:
108           pammixmulti input*.ppm >output.ppm
109       </pre>
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111       Mix these same images by taking each pixel from a randomly selected input
112       image:
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114           pammixmulti --blend=random input*.ppm >output.ppm
115       </pre>
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117       Use a mask image to control the fading among input images on a
118       pixel-by-pixel basis:
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120           pammixmulti --blend=mask --maskfile=mask.pgm >output.pam \
121              one.pam two.pam three.pam four.pam
122       </pre>
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124       Do the same but with more abrupt transitions:
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126           pammixmulti --blend=mask --maskfile=mask.pgm --stdev=0.0 >output.pam \
127              one.pam two.pam three.pam four.pam
128       </pre>
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130       and now with more gradual transitions:
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132           pammixmulti --blend=mask --maskfile=mask.pgm --stdev=1.0 >output.pam \
133              one.pam two.pam three.pam four.pam
134       </pre>
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HISTORY

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

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

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

153       ·
154
155              SYNOPSIS ⟨#synopsis⟩
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157       ·
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159              DESCRIPTION ⟨#description⟩
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161       ·
162
163              OPTIONS ⟨#options⟩
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165       ·
166
167              ARGUMENTS ⟨#arguments⟩
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169       ·
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171              EXAMPLES ⟨#examples⟩
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173       ·
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175              HISTORY ⟨#history⟩
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177       ·
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179              AUTHOR ⟨#author⟩
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181       ·
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183              SEE ALSO ⟨#seealso⟩
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DOCUMENT SOURCE

186       This manual page was generated by the Netpbm tool 'makeman'  from  HTML
187       source.  The master documentation is at
188
189              http://netpbm.sourceforge.net/doc/pammixmulti.html
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191                               18 November 2018     Pammixmulti User Manual(0)