pampaintspill(1)

1Pampaintspill User Manual(0)                      Pampaintspill User Manual(0)
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NAME

6       pampaintspill - smoothly spill colors into the background
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SYNOPSIS

10       pampaintspill  [--bgcolor=color] [--wrap] [--all] [--downsample=number]
11       [--power=number] [filename]
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13       Minimum unique abbreviations of option are  acceptable.   You  may  use
14       double hyphens instead of single hyphen to denote options.  You may use
15       white space in place of the equals sign to separate an option name from
16       its value.
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DESCRIPTION

20       This program is part of Netpbm(1).
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22       pampaintspill  produces  a  smooth  color gradient from all of the non-
23       background-colored pixels in  an  input  image,  effectively  "spilling
24       paint"  onto  the  background.  pampaintspill is similar to pamgradient
25       but differs in the following characteristics:
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29       ·      pampaintspill accepts any number of paint
30                    sources (non-background-colored  pixels),  which  can  lie
31              anywhere
32                    on the canvas.  pamgradient accepts exactly
33                    four paint sources, one in each corner of the image.
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36       ·      pampaintspill requires an input image while
37                    pamgradient generates a new image from
38                    scratch.
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41       ·      pampaintspill can produce tileable output and
42                    can  control how tightly the gradient colors bind to their
43              source
44                    pixels.
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47       Results are generally best when the input image contains  just  a  few,
48       crisp  spots  of  color.  Use  your  drawing program's pencil tool - as
49       opposed to a paintbrush or airbrush tool - with a small nib.
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OPTIONS

53       In addition to the options common to all programs  based  on  libnetpbm
54       (most notably -quiet, see
55        Common  Options ⟨index.html#commonoptions⟩ ), pampaintspill recognizes
56       the following command line options:
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60       --bgcolor=color
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62              Explicitly specify the background color. color can be
63                    specified  using  any  of  the  formats  accepted  by  the
64              pnm_parsecolor()              library                    routine
65              ⟨libnetpbm_image.html#colorname⟩  such as red or #ff0000.  If
66                    --bgcolor is not specified, pampaintspill makes an
67                    educated guess about the background  color  based  on  the
68              colors in the
69                    image's corners.
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72       --wrap
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74              Allow gradients to wrap around image borders. That is, colors
75                    that spill off the right side of the image reappear on the
76              left side of
77                    the image and likewise for left/right, top/bottom, and
78                    bottom/top. --wrap makes images tileable,  which  is  nice
79              for
80                    producing desktop backgrounds.
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83       --all
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85              Recolor all pixels, not just background pixels. Normally,
86                    non-background-colored  pixels  in  the input image appear
87              unmodified in
88                    the output image. With --all, all pixels are colored
89                    based on their distance from all of the (other)  non-back‐
90              ground-colored
91                    pixels.
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94       --downsample=number
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96              Ignore all but number non-background-colored pixels.
97                    When a large number of pixels in the input image differ in
98              color from
99                    the background, pampaintspill runs very slowly. The
100                    --downsample option randomly selects  a  given  number  of
101              colored
102                    pixels  to  use  as  paint  sources  for the gradients and
103              ignores the rest,
104                    thereby trading off image quality for speed of execution.
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107       --power=number
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109              Control how color intensity changes as a function of the
110                    distance from a paint source. The default value for number
111              is
112                    -2.0,  which  means  that  intensity drops (because of the
113              minus sign) with
114                    the square (because of the 2.0) of the distance from  each
115              paint
116                    source.  -2.0  generally works well in practice, but other
117              values can be
118                    specified for various special  effects.  With  very  small
119              numbers of paint
120                    sources, -1.0 may produce subtler gradients, but these get
121              muddier as
122                    the number of paint sources  increases.  Positive  numbers
123              (e.g., 1.0 and
124                    2.0)  make the paint sources stand out in the output image
125              by pushing the
126                    gradients away from them.
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HISTORY

159       pampaintspill was new in Netpbm 10.50 (March 2010).
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COPYRIGHT

164       Copyright © 2010 Scott Pakin, scott+pbm@pakin.org.
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168       ·
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170              SYNOPSIS ⟨#synopsis⟩
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172       ·
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174              DESCRIPTION ⟨#description⟩
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176       ·
177
178              OPTIONS ⟨#options⟩
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180       ·
181
182              SEE ALSO ⟨#seealso⟩
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184       ·
185
186              HISTORY ⟨#history⟩
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188       ·
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190              COPYRIGHT ⟨#copyright⟩
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DOCUMENT SOURCE

193       This manual page was generated by the Netpbm tool 'makeman'  from  HTML
194       source.  The master documentation is at
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196              http://netpbm.sourceforge.net/doc/pampaintspill.html
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198netpbm documentation           09 February 2020   Pampaintspill User Manual(0)