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

13       pammixmulti - blend together multiple PAM images
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SYNOPSIS

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

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

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

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

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

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

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

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

152       ·
153
154              SYNOPSIS ⟨#synopsis⟩
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156       ·
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158              DESCRIPTION ⟨#description⟩
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160       ·
161
162              OPTIONS ⟨#options⟩
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164       ·
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166              ARGUMENTS ⟨#arguments⟩
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168       ·
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170              EXAMPLES ⟨#examples⟩
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172       ·
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174              HISTORY ⟨#history⟩
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176       ·
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178              AUTHOR ⟨#author⟩
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180       ·
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182              SEE ALSO ⟨#seealso⟩
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DOCUMENT SOURCE

185       This manual page was generated by the Netpbm tool 'makeman'  from  HTML
186       source.  The master documentation is at
187
188              http://netpbm.sourceforge.net/doc/pammixmulti.html
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190                               18 November 2018     Pammixmulti User Manual(0)