Help for CLEANLABEL

PURPOSE

   This program can be used to remove duplicated label items from the history 
label of any VICAR image.
EXECUTION

The following operational options are available.

Parameters in capitalized letters and words in quotes are to be entered 
literally, while words in braces represent values to be entered by the user.  
Default options are indicated.  The terms "keyword" and "label item" are used 
interchangeably.

Output file options:

   OUT = (null value)  --->default<---
	This option will cause the input file's history label to be cleaned.

   OUT = <filename>
	Create a new file (named by the user) which contains (a) the cleaned 
	history label and (b) a copy of the image in the input file.  The 
	input file label is not changed.

	CLEANLABEL assumes that the filename specification is complete.  The 
	output file will put in your default directory on magnetic disk unless 
	you specify the destination disk and directory.
Keyword options:

   KEYWORDS = (null value) --->default<---
	This option will result in the cleaning of all history label items.

   KEYWORDS = <list of label items>
	Clean only the label items listed.  Up to 50 items can be specified.
	Only the label items should be entered -- do not enter values.  
	E.G. You list an image label and decide to remove the line
	
	SLAT=40.0

	To do this, specify KEYWORDS = SLAT.  The value of 40.0 is removed 
	automatically.

	CLEANLABEL will not clean the task header keywords TASK, USER, and 
	DAT_TIM.  It also will not clean any system header keywords.
Cleaning options:

   MODE = "keeplast" --->default<---
	This option will cause LABELCLEAN to delete all instances it finds
	of each keyword, except the instance which is most recent, in terms
	of the history of the image.

   MODE = "keepfrst"
	In this mode, the oldest instance of each task is kept and all others
	are deleted.
OPERATION

This program assumes that the input Vicar image is in band sequential (BSQ)
format.

HISTORY

	Author : Megan O'Shaughnessy  9-21-1989
	Revised :

	1991-10-11 MOS - Fixed FR 70991, dereferenced unit number in calls to XVSIGNAL, in 
	                 keeping with changes to that subroutine.
        1994-05-25 RNR(CRI) - Made portable for UNIX.
                              For SUN "close_files" proc changed to "cclose_files" to avoid 
                              improper linking. 
        2019-07-18 WLB - IDS-7923: replaced sprintf with snprintf. Misc cleanup.

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PARAMETERS: