spottopgm(1) - Man pages

Spottopgm User Manual(1) General Commands Manual Spottopgm User Manual(1)

NAME
spottopgm - convert SPOT satellite images to a PGM image

SYNOPSIS
spottopgm [-1|-2|-3] [Firstcol Firstline Lastcol Lastline] inputfile

DESCRIPTION
This program is part of Netpbm(1).

spottopgm converts the named inputfile to PGM format, defaulting to the
first color and the whole SPOT image unless you specify otherwise with
the options.

OPTIONS
In addition to the options common to all programs based on libnetpbm
(most notably -quiet, see ]8;;index.html#commonoptions\ Common Options]8;;\ ), spottopgm recognizes the
following command line options:

-1

-2

-3 Extract the given color from the SPOT image. The colors are in-
frared, visible light, and ultraviolet, although I don't know
which corresponds to which number. If the image is in color,
spottopgm announces this on Standard Error. The default color is
1.

PARAMETERS
Firstcol Firstline Lastcol Lastline
Extract the specified rectangle from the SPOT image. Most SPOT
images are 3000 lines long and 3000 or more columns wide. Unfor-
tunately, the SPOT format only gives the width and not the
length. The width is printed on standard error. The default
rectangle is the width of the input image by 3000 lines.

LIMITATIONS
spottopgm doesn't determine the length of the input file; this would in-
volve two passes over the input file. It defaults to 3000 lines in-
stead.

spottopgm could extract a three-color image (as a PPM), but I didn't
feel like making the program more complicated than it is now. Besides,
there is no one-to-one correspondence between red, green, blue and in-
frared, visible and ultraviolet.

I've had only a limited number of SPOT images to play with, and there-
fore wouldn't guarantee that this will work on any other images.

AUTHOR
Warren Toomey wkt@csadfa.cs.adfa.oz.au