1Pgmramp User Manual(0)                                  Pgmramp User Manual(0)
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NAME

6       pgmramp - generate a grayscale ramp
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SYNOPSIS

10       pgmramp -lr|-tb|-rectangle|-ellipse -maxval=maxval width height
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12       All  options  can  be abbreviated to their shortest unique prefix.  You
13       may use two hyphens instead of one to designate an option.  You may use
14       either  white  space  or  an equals sign between an option name and its
15       value.
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DESCRIPTION

19       This program is part of Netpbm(1).
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21       Generates a graymap of the specified size containing  a  black-to-white
22       ramp.   These ramps are useful for multiplying with other images, using
23       pamarith.
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25       The ramp is linear in brightness, not intensity.  I.e.  the  gamma-cor‐
26       rected  sample  values  in the PGM rise linearly with distance from the
27       corner of the image.  If you want a ramp that is linear in light inten‐
28       sity, use pnmgamma with pgmramp.
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30       To  generate  a simple ramp of all the values from 0 to maxval, and not
31       necessarily a graphic image, use pamseq(1).
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33       ppmrainbow does something similar to what pgmramp does, but for  color.
34       The image fades between two colors of your choice.
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OPTIONS

39       You must specify exactly one of the ramp type options.
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42       -lr    A left to right ramp.
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45       -tb    A top to bottom ramp.
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48       -rectangle
49              An  outside-in  rectangular  ramp.  It is black around the edges
50              and white in the center.
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53       -ellipse
54              An outside-in elliptical ramp.  It is black around the edge  and
55              white in the center.
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58       -maxval=maxval
59                   The maxval for the generated image.  Default is 255.
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61                   This  option  did  not exist before June 2002.  Before, the
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63                   always 255.
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SEE ALSO

70       pamarith(1),  pnmgamma(1),  pamseq(1),  ppmrainbow(1),  pamgradient(1),
71       pgm(1)
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AUTHOR

76       Copyright (C) 1989 by Jef Poskanzer.
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80netpbm documentation             04 June 2002           Pgmramp User Manual(0)