1Pampaintspill User Manual(0) Pampaintspill User Manual(0)
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6 pampaintspill - smoothly spill colors into the background
7
10 pampaintspill [--bgcolor=color] [--wrap] [--all] [--downsample=number]
11 [--near=number] [--power=number] [filename] [-randomseed=integer]
12 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.
17
20 This program is part of Netpbm(1).
21 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:
26 • 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.
34 • pampaintspill requires an input image while
37 pamgradient generates a new image from
38 scratch.
39 • pampaintspill can produce tileable output and
42 can control how tightly the gradient colors bind to their
43 source
44 pixels.
45 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 op‐
49 posed to a paintbrush or airbrush tool - with a small nib.
50
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:
57 --bgcolor=color
61 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.
70 --wrap
73 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.
81 --all
84 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.
92 --downsample=number
95 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 ig‐
103 nores the rest,
104 thereby trading off image quality for speed of execution.
105 --near=number
108 Consider only the nearest number paint sources when computing
110 a pixel's new color. The default is to consider all paint
111 sources.
112 In most cases, number should be fairly small, or its im‐
113 pact
114 will be minimal and execution time will increase unneces‐
115 sarily. A
116 value of 1 produces a coloring that looks a lot like a
117 Voronoi
118 diagram.
119 This option was new in Netpbm 10.97 (December 2021).
121 --power=number
124 Control how color intensity changes as a function of the
126 distance from a paint source. The default value for number
127 is
128 -2.0, which means that intensity drops (because of the mi‐
129 nus sign) with
130 the square (because of the 2.0) of the distance from each
131 paint
132 source. -2.0 generally works well in practice, but other
133 values can be
134 specified for various special effects. With very small
135 numbers of paint
136 sources, -1.0 may produce subtler gradients, but these get
137 muddier as
138 the number of paint sources increases. Positive numbers
139 (e.g., 1.0 and
140 2.0) make the paint sources stand out in the output image
141 by pushing the
142 gradients away from them.
143 -randomseed=integer
146 This is the seed for the random number generator that generates
148 the
149 pixels.
150 Use this to ensure you get the same image on separate invoca‐
152 tions.
153 This option was new in Netpbm 10.94 (March 2021).
155
160 •
161 pamgradient(1)
163 •
165 ppmmake(1),
167 •
169 ppmrainbow(1),
171 •
173 pgmramp(1),
175 •
177 ppmpat(1),
179 •
181 pam(1)
183
187 pampaintspill was new in Netpbm 10.50 (March 2010).
188
192 Copyright © 2010–2021 Scott Pakin, scott+pbm@pakin.org.
193
196 •
197 SYNOPSIS ⟨#synopsis⟩
199 •
201 DESCRIPTION ⟨#description⟩
203 •
205 OPTIONS ⟨#options⟩
207 •
209 SEE ALSO ⟨#seealso⟩
211 •
213 HISTORY ⟨#history⟩
215 •
217 COPYRIGHT ⟨#copyright⟩
219
221 This manual page was generated by the Netpbm tool 'makeman' from HTML
222 source. The master documentation is at
223 http://netpbm.sourceforge.net/doc/pampaintspill.html
225netpbm documentation 02 November 2021 Pampaintspill User Manual(0)