The purpose of this program is to resize a raster file according to instructions from the user. It was designed specifically to resize the extremely large raster files created by IDL's function graphics commands from within an IDL program. It requires ImageMagick be installed and able to be called from a SPAWN command from within IDL.
Graphics
rasterfile: in, required, type=string
Set this parameter to the name of the raster file to be resized. The resized
file will have this same name unless the `KEEP_ORIGINAL` keyword is set, in
which case an "_rs" will be appended to the base name given by this parameter.
percentage: in, optional, type=float
A resize percentage. A value of 50, for example, will make the output file
half its original size. A file may be made bigger by specifying a percentage
greater than 100 (e.g. 150). The default is to calculate a precentage that makes
the longest dimension of the output file approximately 600 pixels.
keep_original: in, optional, type=boolean
Set this keyword to keep the original file. Otherwise, the file is overwritten with
the resized file. If this keyword is set, the output file will use the same name as
the input file, except an "_rs" will be appended to the base name of the input file.
height: in, optional, type=integer
Set this keyword to set the height of the resulting raster file in pixel units. The width of the
raster will be such as to preserve the aspect ratio of the starting image. This keyword
cannot be used if the `WIDTH` keyword is used at the same time.
silent: in, optional, type=boolean, default=0
Set this keyword to suppress printed output from the program.
width: in, optional, type=integer
Set this keyword to set the resulting width of the raster file. The height of the
raster will be such as to preserve the aspect ratio of the starting image. This keyword
cannot be used if the `HEIGHT` keyword is used at the same time.
Here is how to use this program:: IDL> cgResizeRaster, 'picture.png', /Keep_Original, Width=500
FANNING SOFTWARE CONSULTING:: David W. Fanning 1645 Sheely Drive Fort Collins, CO 80526 USA Phone: 970-221-0438 E-mail: david@idlcoyote.com Coyote's Guide to IDL Programming: http://www.idlcoyote.com
Change History:: Written, 15 January 2014 by David W. Fanning.
Copyright (c) 2014, Fanning Software Consulting, Inc.