GETIMAGE
The purpose of this function is to allow the user to open either unformmated or XDR binary image files of up to eight dimensions.
Widgets, File I/O.
image = GETIMAGE(filename)
filename: The name of the file to open for reading.
CANCEL: An output variable that can be set to a named variable. The value of the return variable will be 1 if the user clicked the "Cancel" button or if there was a problem reading the file. DATATYPE: The "type" of data you wish to read out of the file. The data type corresponds to the Size(image, /TYPE) value. Here are the types supported: BYTE 1 (default) INTEGER 2 LONG INTEGER 3 FLOAT 4 DOUBLE 5 UNSIGNED INTEGER 12 UNSIGNED LONG INTEGER 13 64-bit LONG 14 64-bit UNSIGNED LONG 15 DIMENSIONS: A vector of image dimensions. The default value is [256, 256]. DIRECTORY: The name of the directory the file is located in. By default the program looks in the "coyote" directory under the main IDL directory, if one exists. Otherwise, it defaults to the current directory. ENDIAN: Set this keyword to an integer that indicates the byte ordering of the data file. If you don't know what byte order means, or you don't know anything about the byte order of the data, or if you are sure the data was created on the same type of machine you are now running IDL on, then just accept the default of 0 or "native" ordering. If you are wrong, you will soon know it and you can set the keyword to another value on your next try. :-) If you know the machine was created on a big endian machine (such as a Sun or HP workstation), set this value to 1 (Big Endian). If e you are sur the image data was create on a little endian machine (such as a Windows PC or laptop running LINUX), set the value to 2 (Little Endian). HEADER: The size of any header information in the file in BYTES. Default is 0. HEADDATA: An optional output keyword that will contain the header information read from the file. PARENT: The group leader for this widget program. The PARENT is required if GETIMAGE is called from another widget program in order to make this program a MODAL widget program. XDR: Set this keyword if the binary file is of XDR type. The default type is "Unformatted". XOFFSET: This is the X offset of the program on the display. The program will be placed approximately in the middle of the display by default. YOFFSET: This is the Y offset of the program on the display. The program will be placed approximately in the middle of the display by default.
None.
A "CANCEL" operation is indicated by a 0 return value. Any error in reading the file results in a 0 return value.
To load the image "galaxy.dat" in the $IDL/examples/data directory, type: image = GETIMAGE('galaxy.dat', DIRECTORY=!DIR + '/examples/data', $ DIMENSIONS=[256,256], Cancel=cancelled, Parent=event.top) IF NOT cancelled THEN TV, image
Written by: David Fanning, 3 February 96. Fixed bug that prevented reading INTEGER data. 19 Dec 96. Modifed program for IDL 5 MODAL operation. 19 Oct 97. Added CANCEL keyword. 27 Oct 97. DWF. Fixed CANCLE keyword spelling. Sigh... 29 JUN 98. DWF. Added COYOTE_FIELD, improved appearance. 19 NOV 99. DWF. Updated with latest version of COYOTE_FIELD. 18 FEB 2000. DWF. Added CATCH keyword so the program will break when I want it to. :-) 18 MAR 2000. DWF. Added GROUP_LEADER keyword, which is synonymous with PARENT. 31 MAR 2000. DWF. Updated obsolete PICKFILE call to DIALOG_PICKFILE. 17 JAN 2001. DWF. Extensive update for IDL Programming Techniques, 3rd Edition. 1 November 2006. DWF. XSIZE, YSIZE, CATCH, and FRAMES keyword made obsolete. HEADDATA, ENDIAN, DATATYPE, DIMENSIONS keywords added. Added ability to parse fully qualified file names passed from Dialog_Pickfile. 30 Oct 2010. DWF. IF a file name is not passed into the program, it asks the user to select one now. 10 Jan 2011. DWF. Problem with SWAP_ENDIAN keywords fixed. 7 March 2011. DWF.