SAC Command Reference Manual

GRAYSCALE

SUMMARY

Produces grayscale images of data in memory.

Deprecation Warning

This command is deprecated as it relies on external software.

SYNTAX

GRAYSCALE {options}

where options are one or more of the following:

VIDEOTYPE NORMAL|REVERSED
SCALE v
ZOOM n
XCROP n1 n2|ON|OFF
YCROP n1 n2|ON|OFF
SPECIAL NOTE

This command uses executables that are not distributed with SAC. To use this command you must first install the Utah Raster Toolkit. The Utah Raster Toolkit can be obtained via anonymous FTP as follows:

ftp cs.utah.edu
cd pub
get urt-3.0.tar.Z

If ARPAnet is not available, or if you have questions about the Utah Raster Toolkit, send mail to: toolkit-requestCS.UTAH.EDU (ARPA), OR {ihnp4,decvax}!utah-cs!toolkit-request (UUCP).

INPUT

VIDEO NORMAL:Set video type to normal. In normal mode, data with near minimum values are black and data near maximum are white.
VIDEO REVERSED:Set video type to reversed. In reversed mode, data with near minimum values are white and data near maximum are black.
SCALE v:Change data scaling factor to v. The data is scaled by raising it to the vth power. Values less than one will smooth the image, reducing peaks and valleys. Values greater than one will spread the data.
ZOOM n:Image is increased to n times its normal size by pixel replication.
XCROP n1 n2:Turn x cropping option on and change cropping limits to n1 and n2. The limits are in terms of the image size.
XCROP {ON}:Turn x cropping option on and use previously specified cropping limits.
XCROP OFF:Turn x cropping option off. All of the data in the x direction is displayed.
YCROP n1 n2:Turn y cropping option on and change cropping limits to n1 and n2. The limits are in terms of the image size.
YCROP {ON}:Turn y cropping option on and use previous specified cropping limits.
YCROP OFF:Turn y cropping option off. All of the data in the y direction is displayed.

DEFAULT VALUES

GRAYSCALE VIDEOTYPE NORMAL SCALE 1.0 ZOOM 1 XCROP OFF YCROP OFF

DESCRIPTION

This command can be used to produce a grayscale image of the output of the SPECTROGRAM command or of any other two-dimensional array data. The SAC data displayed by this command must of of file type "xyz".

ANOTHER SPECIAL NOTE: SAC starts a shell script which runs the image manipulation and display programs and then displays the SAC prompt again. There is a delay, significant for large images and/or slower machines, before the image is actually displayed.

LIMITATIONS

Images of 512 by 1000 are the maximum displayed.

ACKNOWLEDGEMENTS

This command was developed by Terri Quinn. The grayscale images are maninpulated and display using the University of Utah's Raster Toolkit. The Utah Raster Toolkit and accompanying documentation; John W. Peterson, Rod G. Bogart, and Spencer W. Thomas.

HEADER VARIABLES

REQUIRED: : IFTYPE, NXSIZE, NYSIZE

ERROR MESSAGES

  • SAC> getsun: Command not found.
    • Several utility programs distributed with the Utah Raster Toolkit are required.

SEE COMMANDS

SPECTROGRAM

LATEST REVISION

March 22, 1990 (Version 10.5a)