rgb3toppm(1) General Commands Manual rgb3toppm(1)NAME
rgb3toppm - combine three portable graymaps into one portable pixmap
SYNOPSIS
rgb3toppm redpgmfile greenpgmfile bluepgmfile
DESCRIPTION
Reads three portable graymaps as input. Combines them and produces one portable pixmap as output.
SEE ALSO ppmtorgb3(1), pgmtoppm(1), ppmtopgm(1), ppm(5), pgm(5)AUTHOR
Copyright (C) 1991 by Jef Poskanzer.
15 February 1990 rgb3toppm(1)
Check Out this Related Man Page
ppmtopgm(1) General Commands Manual ppmtopgm(1)NAME
ppmtopgm - convert a portable pixmap into a portable graymap
SYNOPSIS
ppmtopgm [ppmfile]
DESCRIPTION
Reads a portable pixmap as input. Produces a portable graymap as output. The output is a "black and white" rendering of the original
image, as in a black and white photograph. The quantization formula used is .299 r + .587 g + .114 b.
Note that although there is a pgmtoppm program, it is not necessary for simple conversions from pgm to ppm , because any ppm program can
read pgm (and pbm ) files automatically. pgmtoppm is for colorizing a pgm file. Also, see ppmtorgb3 for a different way of converting
color to gray. And ppmdist generates a grayscale image from a color image, but in a way that makes it easy to differentiate the original
colors, not necessarily a way that looks like a black and white photograph.
QUOTE
Cold-hearted orb that rules the night
Removes the colors from our sight
Red is gray, and yellow white
But we decide which is right
And which is a quantization error.
SEE ALSO pgmtoppm(1),ppmtorgb3(1),rgb3toppm(1),ppmdist(1),ppm(5),pgm(5)AUTHOR
Copyright (C) 1989 by Jef Poskanzer.
10 April 2000 ppmtopgm(1)
Introduction
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Introduction
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