pnmarith(1) General Commands Manual pnmarith(1)NAME
pnmarith - perform arithmetic on two portable anymaps
SYNOPSIS
pnmarith -add|-subtract|-multiply|-difference|-minimum|-maximum. pnmfile1 pnmfile2
DESCRIPTION
Reads two portable anymaps as input. Performs the specified arithmetic operation, and produces a portable anymap as output. The two input
anymaps must be the same width and height.
The arithmetic is performed between corresponding pixels in the two anymaps, as if maxval was 1.0, black was 0.0, and a linear scale in
between. Results that fall outside of [0..1) are truncated.
The operator -difference calculates the absolute value of pnmarith -subtract pnmfile1 pnmfile2, i.e. no truncation is done.
All flags can be abbreviated to their shortest unique prefix.
SEE ALSO pbmmask(1), pnmpaste(1), pnminvert(1), pnm(5)AUTHOR
Copyright (C) 1989, 1991 by Jef Poskanzer. Lightly modified by Marcel Wijkstra <wijkstra@fwi.uva.nl>
26 August 1993 pnmarith(1)
Check Out this Related Man Page
pnmpaste(1) General Commands Manual pnmpaste(1)NAME
pnmpaste - paste a rectangle into a portable anymap
SYNOPSIS
pnmpaste [-replace|-or|-and |-xor] frompnmfile x y [intopnmfile]
DESCRIPTION
Reads two portable anymaps as input. Inserts the first anymap into the second at the specified location, and produces a portable anymap
the same size as the second as output. If the second anymap is not specified, it is read from stdin. The x and y can be negative, in
which case they are interpreted relative to the right and bottom of the anymap, respectively.
This tool is most useful in combination with pnmcut. For instance, if you want to edit a small segment of a large image, and your image
editor cannot edit the large image, you can cut out the segment you are interested in, edit it, and then paste it back in.
Another useful companion tool is pbmmask.
pnmcomp is, a more general tool, except that it lacks the "or," "and," and "xor" functions. pnmcomp allows you to specify an alpha mask in
order to have only part of the inserted image get inserted. So the inserted pixels need not be a rectangle. You can also have the
inserted image be translucent, so the resulting image is a mixture of the inserted image and the base image.
The optional flag specifies the operation to use when doing the paste. The default is -replace. The other, logical operations are only
allowed if both input images are bitmaps. These operations act as if white is TRUE and black is FALSE.
All flags can be abbreviated to their shortest unique prefix.
SEE ALSO pnmcomp(1), pnmcut(1), pnminvert(1), pnmarith(1), pbmmask(1), pnm(5)AUTHOR
Copyright (C) 1989, 1991 by Jef Poskanzer.
21 February 1991 pnmpaste(1)
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