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<P><CENTER>
<a href="0381-0384.html">Previous</A> | <a href="../ewtoc.html">Table of Contents</A> | <a href="0389-0390.html">Next</A></CENTER></P>
<A NAME="PAGENUM-385"><P>Page 385</P></A>
<H3><A NAME="ch01_ 264">
pnmcrop
</A></H3>
<P>pnmcrop—Crop a portable anymap
</P>
<P><B>
SYNOPSIS
</B>
</P>
<!-- CODE SNIP //-->
<PRE>
pnmcrop [-white|-black][-left][-right][-top][-bottom][pnmfile]
</PRE>
<!-- END CODE SNIP //-->
<P><B>
DESCRIPTION
</B>
</P>
<P>pnmcrop reads a portable anymap as input, removes edges that are the background color, and produces a portable anymap
as output.
</P>
<P><B>
OPTIONS
</B>
</P>
<P>By default, it makes a guess as to what the background color is. You can override the default with the
-white and -black flags.
</P>
<P>The options -left, -right, -top and -bottom restrict cropping to the sides specified. The default is to crop all sides of
the image.
</P>
<P>All flags can be abbreviated to their shortest unique prefix.
</P>
<P><B>
SEE ALSO
</B>
</P>
<!-- CODE SNIP //-->
<PRE>pnmcut(1), pnm(5)
</PRE>
<!-- END CODE SNIP //-->
<P><B>
AUTHOR
</B>
</P>
<P>Copyright " 1989 by Jef Poskanzer.
</P>
<P>25 February 1989
</P>
<H3><A NAME="ch01_ 265">
pnmcut
</A></H3>
<P>pnmcut—Cut a rectangle out of a portable anymap
</P>
<P><B>
SYNOPSIS
</B>
</P>
<!-- CODE SNIP //-->
<PRE>
pnmcut x y width height [pnmfile]
</PRE>
<!-- END CODE SNIP //-->
<P><B>
DESCRIPTION
</B>
</P>
<P>pnmcut reads a portable anymap as input, extracts the specified rectangle, and produces a portable anymap as output. The
x and y can be negative, in which case they are interpreted relative to the right and bottom of the anymap, respectively.
</P>
<P><B>
SEE ALSO
</B>
</P>
<!-- CODE SNIP //-->
<PRE>
pnm(5)
</PRE>
<!-- END CODE SNIP //-->
<P><B>
AUTHOR
</B>
</P>
<P>Copyright " 1989 by Jef Poskanzer.
</P>
<P>21 February 1989
</P>
<H3><A NAME="ch01_ 266">
pnmdepth
</A></H3>
<P>pnmdepth—Change the maxval in a portable anymap
</P>
<P><B>
SYNOPSIS
</B>
</P>
<!-- CODE SNIP //-->
<PRE>
pnmdepth newmaxval [pnmfile]
</PRE>
<!-- END CODE SNIP //-->
<A NAME="PAGENUM-386"><P>Page 386</P></A>
<P><B>
DESCRIPTION
</B>
</P>
<P>pnmdepth reads a portable anymap as input, scales all the pixel values, and writes out the image with the new
maxval. Scaling the colors down to a smaller
maxval will result in some loss of information.
</P>
<P>Be careful of off-by-one errors when choosing the new
maxval. For instance, if you want the color values to be five bits
wide, use a maxval of 31, not 32.
</P>
<P><B>
SEE ALSO
</B>
</P>
<!-- CODE SNIP //-->
<PRE>
pnm(5), ppmquant(1), ppmdither(1)
</PRE>
<!-- END CODE SNIP //-->
<P><B>
AUTHOR
</B>
</P>
<P>Copyright " 1989, 1991 by Jef Poskanzer.
</P>
<P>12 January 1991
</P>
<H3><A NAME="ch01_ 267">
pnmenlarge
</A></H3>
<P>pnmenlarge—Read a portable anymap and enlarge it N times
</P>
<P><B>
SYNOPSIS
</B>
</P>
<!-- CODE SNIP //-->
<PRE>
pnmenlarge N [pnmfile]
</PRE>
<!-- END CODE SNIP //-->
<P><B>
DESCRIPTION
</B>
</P>
<P>pnmenlarge reads a portable anymap as input, replicates its pixels
N times, and produces a portable anymap as output.
</P>
<P>pnmenlarge can only enlarge by integer factors. The slower but more general
pnmscale can enlarge or reduce by arbitrary factors, and
pbmreduce can reduce by integer factors, but only for bitmaps.
</P>
<P>If you enlarge by a factor of 3 or more, you should probably add a
pnmsmooth step; otherwise, you can see the original
pixels in the resulting image.
</P>
<P><B>
SEE ALSO
</B>
</P>
<!-- CODE SNIP //-->
<PRE>
pbmreduce(1), pnmscale(1), pnmsmooth(1), pnm(5)
</PRE>
<!-- END CODE SNIP //-->
<P><B>
AUTHOR
</B>
</P>
<P>Copyright " 1989 by Jef Poskanzer.
</P>
<P>26 February 1989
</P>
<H3><A NAME="ch01_ 268">
pnmfile
</A></H3>
<P>pnmfile—Describe a portable anymap
</P>
<P><B>
SYNOPSIS
</B>
</P>
<!-- CODE SNIP //-->
<PRE>
pnmfile [pnmfile] ...
</PRE>
<!-- END CODE SNIP //-->
<P><B>
DESCRIPTION
</B>
</P>
<P>pnmfile reads one or more portable anymaps as input and writes out short descriptions of the image type, size, and so
on. This is mostly for use in shell scripts, so the format is not particularly pretty.
</P>
<P><B>
SEE ALSO
</B>
</P>
<!-- CODE SNIP //-->
<PRE>
pnm(5), file(1)
</PRE>
<!-- END CODE SNIP //-->
<A NAME="PAGENUM-387"><P>Page 387</P></A>
<P><B>
AUTHOR
</B></P>
<P>Copyright " 1991 by Jef Poskanzer.
</P>
<P>9 January 1991
</P>
<H3><A NAME="ch01_ 269">
pnmflip
</A></H3>
<P>pnmflip—Perform one or more flip operations on a portable anymap
</P>
<P><B>
SYNOPSIS
</B>
</P>
<!-- CODE SNIP //-->
<PRE>
pnmflip [-leftright|-lr][-topbottom|-tb][-transpose|-xy][-rotate90|-r90|-ccw ]
[-rotate270|-r270|-cw ][-rotate180|-r180][pnmfile]
</PRE>
<!-- END CODE SNIP //-->
<P><B>
DESCRIPTION
</B>
</P>
<P>pnmflip reads a portable anymap as input, performs one or more flip operations in the order specified, and writes out
a portable anymap.
</P>
<P><B>
OPTIONS
</B>
</P>
<P>The flip operations available are left for right
(-leftright or -lr); top for bottom (-topbottom or
-tb); and transposition (-transpose or -xy). In addition, some canned concatenations are available:
-rotate90 or -ccw is equivalent to -transpose
-topbottom; -rotate270 or -cw is equivalent to -transpose
-leftright; and -rotate180 is equivalent to -leftright
-topbottom.
</P>
<P>All flags can be abbreviated to their shortest unique prefix.
</P>
<P><B>
SEE ALSO
</B>
</P>
<!-- CODE SNIP //-->
<PRE>pnmrotate(1), pnm(5)
</PRE>
<!-- END CODE SNIP //-->
<P><B>
AUTHOR
</B>
</P>
<P>Copyright" 1989 by Jef Poskanzer.
</P>
<P>25 July 1989
</P>
<H3><A NAME="ch01_ 270">
pnmgamma
</A></H3>
<P>pnmgamma—Perform gamma correction on a portable anymap
</P>
<P><B>
SYNOPSIS
</B>
</P>
<!-- CODE SNIP //-->
<PRE>
pnmgamma value [pnmfile]
pnmgamma redvalue greenvalue bluevalue [pnmfile]
</PRE>
<!-- END CODE SNIP //-->
<P><B>
DESCRIPTION
</B>
</P>
<P>pnmgamma reads a portable anymap as input, performs gamma correction, and produces a portable anymap as output.
</P>
<P>The arguments specify what gamma value(s) to use. A value of 1.0 leaves the image alone, less than 1 darkens it, and
greater than 1 lightens it.
</P>
<P><B>
SEE ALSO
</B>
</P>
<!-- CODE SNIP //-->
<PRE>
pnm(5)
</PRE>
<!-- END CODE SNIP //-->
<P><B>
AUTHOR
</B>
</P>
<P>Copyright" 1991 by Bill Davidson and Jef Poskanzer.
</P>
<P>12 January 1991
</P>
<A NAME="PAGENUM-388"><P>Page 388</P></A>
<H3><A NAME="ch01_ 271">
pnmhistmap
</A></H3>
<P>pnmhistmap—Draw a histogram for a PGM or PPM file
</P>
<P><B>
SYNOPSIS
</B>
</P>
<!-- CODE SNIP //-->
<PRE>
pnmhistmap [-black][-white][-max N][-verbose][pnmfile]
</PRE>
<!-- END CODE SNIP //-->
<P><B>
DESCRIPTION
</B>
</P>
<P>pnmhistmap reads a portable anymap as input, although bitmap (PBM) input produces an error message and no image,
and produces an image showing a histogram of the color (or gray) values in the input. A graymap (PGM) input produces
a bitmap output. A pixmap (PPM) input produces pixmap output with three overlaid histograms: a red one for the red
input, a green one for the green input, and a blue one for the blue input. The output is fixed in size: 256 pixels wide by 200
pixels high.
</P>
<P><B>
OPTIONS
</B>
</P>
<TABLE>
<TR><TD>
-black
</TD><TD>
Ignores the count of black pixels when scaling the histogram.
</TD></TR><TR><TD>
-white
</TD><TD>
Ignores the count of white pixels when scaling the histogram.
</TD></TR></TABLE>
<P>The -black and -white options, which can be used separately or together, are useful for images with a large percentage
of pixels whose value is zero or 255, which can cause the remaining histogram data to become unreadably small. Note that,
for pixmap inputs, these options apply to all colors; if, for example, the input has a large number of bright-red areas, you
will probably want to use the -white option.
</P>
<TABLE>
<TR><TD>
-max N
</TD><TD>
Force the scaling of the histogram to use
N as the largest-count value. This is useful for inputs with a
large percentage of single-color pixels that are not black or white.
</TD></TR><TR><TD>
-verbose
</TD><TD>
Report the progress of making the histogram, including the largest-count value used to scale the output.
</TD></TR></TABLE>
<P>All flags can be abbreviated to their shortest unique prefix.
</P>
<P><B>
BUGS
</B>
</P>
<P>Assumes maxval is always 255. Images with a smaller
maxval will only use the lower-value side of the histogram. This can
be overcome either by piping the input through pnmdepth
255 or by cutting and scaling the lower-value side of the
histogram. Neither is a particularly elegant solution.
</P>
<P>Should allow the output size to be specified.
</P>
<P><B>
SEE ALSO
</B>
</P>
<!-- CODE SNIP //-->
<PRE>
pgmhist(1), ppmhist(1), pgm(5), ppm(5)
</PRE>
<!-- END CODE SNIP //-->
<P><B>
AUTHOR
</B>
</P>
<P>Wilson H. Bent, Jr. (whb@usc.edu).
</P>
<P>25 October 1993
</P>
<H3><A NAME="ch01_ 272">
pnmindex
</A></H3>
<P>pnmindex—Build a visual index of a bunch of anymaps
</P>
<P><B>
SYNOPSIS
</B>
</P>
<!-- CODE SNIP //-->
<PRE>
pnmindex [-size N][-across N][-colors N][-black] pnmfile ...
</PRE>
<!-- END CODE SNIP //-->
<P><B>
DESCRIPTION
</B>
</P>
<P>This script makes small versions of a bunch of anymaps, adds labels, and concatenates them together into a collage.
</P>
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