Pampaintspill User Manual(1)General Commands ManuaPampaintspill User Manual(1)
NAME
pampaintspill - smoothly spill colors into the background
SYNOPSIS
pampaintspill [--bgcolor=color] [--wrap] [--all] [--downsample=number]
[--near=number] [--power=number] [filename] [-randomseed=integer]
Minimum unique abbreviations of option are acceptable. You may use
double hyphens instead of single hyphen to denote options. You may use
white space in place of the equals sign to separate an option name from
its value.
DESCRIPTION
This program is part of Netpbm(1).
pampaintspill produces a smooth color gradient from all of the non-
background-colored pixels in an input image, effectively "spilling
paint" onto the background. pampaintspill is similar to pamgradient
but differs in the following characteristics:
• pampaintspill accepts any number of paint
sources (non-background-colored pixels), which can lie
anywhere
on the canvas. pamgradient accepts exactly
four paint sources, one in each corner of the image.
• pampaintspill requires an input image while
pamgradient generates a new image from
scratch.
• pampaintspill can produce tileable output and
can control how tightly the gradient colors bind to their
source
pixels.
Results are generally best when the input image contains just a few,
crisp spots of color. Use your drawing program's pencil tool - as op-
posed to a paintbrush or airbrush tool - with a small nib.
OPTIONS
In addition to the options common to all programs based on libnetpbm
(most notably -quiet, see
Common Options ⟨index.html#commonoptions⟩ ), pampaintspill recognizes
the following command line options:
--bgcolor=color
Explicitly specify the background color. color can be
specified using any of the formats accepted by the
pnm_parsecolor() library routine
⟨libnetpbm_image.html#colorname⟩ such as red or #ff0000. If
--bgcolor is not specified, pampaintspill makes an
educated guess about the background color based on the
colors in the
image's corners.
--wrap
Allow gradients to wrap around image borders. That is, colors
that spill off the right side of the image reappear on the
left side of
the image and likewise for left/right, top/bottom, and
bottom/top. --wrap makes images tileable, which is nice
for
producing desktop backgrounds.
--all
Recolor all pixels, not just background pixels. Normally,
non-background-colored pixels in the input image appear
unmodified in
the output image. With --all, all pixels are colored
based on their distance from all of the (other) non-back-
ground-colored
pixels.
--downsample=number
Ignore all but number non-background-colored pixels.
When a large number of pixels in the input image differ in
color from
the background, pampaintspill runs very slowly. The
--downsample option randomly selects a given number of
colored
pixels to use as paint sources for the gradients and ig-
nores the rest,
thereby trading off image quality for speed of execution.
--near=number
Consider only the nearest number paint sources when computing
a pixel's new color. The default is to consider all paint
sources.
In most cases, number should be fairly small, or its im-
pact
will be minimal and execution time will increase unneces-
sarily. A
value of 1 produces a coloring that looks a lot like a
Voronoi
diagram.
This option was new in Netpbm 10.97 (December 2021).
--power=number
Control how color intensity changes as a function of the
distance from a paint source. The default value for number
is
-2.0, which means that intensity drops (because of the mi-
nus sign) with
the square (because of the 2.0) of the distance from each
paint
source. -2.0 generally works well in practice, but other
values can be
specified for various special effects. With very small
numbers of paint
sources, -1.0 may produce subtler gradients, but these get
muddier as
the number of paint sources increases. Positive numbers
(e.g., 1.0 and
2.0) make the paint sources stand out in the output image
by pushing the
gradients away from them.
-randomseed=integer
This is the seed for the random number generator that generates
the
pixels.
Use this to ensure you get the same image on separate invoca-
tions.
This option was new in Netpbm 10.94 (March 2021).
SEE ALSO
•
pamgradient(1)
•
ppmmake(1),
•
ppmrainbow(1),
•
pgmramp(1),
•
ppmpat(1),
•
pam(1)
HISTORY
pampaintspill was new in Netpbm 10.50 (March 2010).
COPYRIGHT
Copyright © 2010–2021 Scott Pakin, scott+pbm@pakin.org.
Table Of Contents
•
SYNOPSIS ⟨#synopsis⟩
•
DESCRIPTION ⟨#description⟩
•
OPTIONS ⟨#options⟩
•
SEE ALSO ⟨#seealso⟩
•
HISTORY ⟨#history⟩
•
COPYRIGHT ⟨#copyright⟩
DOCUMENT SOURCE
This manual page was generated by the Netpbm tool 'makeman' from HTML
source. The master documentation is at
http://netpbm.sourceforge.net/doc/pampaintspill.html
netpbm documentation 02 November 2021 Pampaintspill User Manual(1)
Generated by dwww version 1.15 on Sat Jun 29 02:17:29 CEST 2024.