Help for STRETCH3D

This program allows the user to rescale their data to either 
halfword or byte using either the max and min or the mean +/-
N standard deviations. The output can either be to separate files 
or to a single BIL file.
Cognizant programmer S. J. Hook Extn 4-0974 
Geology Group Section 326.

PARAMETERS:

If keyword SINGLE is selected all channels will be written out in a single BIL file. If keyword MULTI is selected each channel will be output in separate files. The names for these files are assigned in variable OUT

OUT

Output dataset. If KEYWORD MULTI was selected DO NOT provide an extension to the filename in OUT. The filename will be automatically appended with the channel number of the output

SIZE

The standard vicar size field (sl,ss,nl,ns)

SL

Starting line

SS

Starting sample

NL

Number of lines

NS

Number of samples

JSTART

Start Channnel

NCHAN

Number of channels

NSDEV

If NSDEV is greater than 0 data will be rescaled using the mean +/- NSDEV std dev., where NSDEV is the number of std dev.

USER

If you select YES for this variable your data will be rescaled using the usermax and usermin values.

USERMAX

If usermax is not equal to -99.0 and "USER = YES", the usermax value will be used instead of the calculated max value.

USERMIN

if usermin is not equal to 99.0 and "USER = YES", the usermin value will be used instead of the calculated min value

BADL

Any pixels with this value will be set to zero if output is byte or -30000 if the output is half.

BADH

Any pixels with this value will be set to 255 if output is byte or 30000 if the output is half. The defaults for BADL and BADH are 0.0 and any zero values in the input will be set to zero in the output.

DATATYPE

If keyword BYTE selected data rescaled to byte. If keyword HALF selected data rescaled to halfword

SCALING

If keyword ALL selected data are rescaled using max/min or mean+/- std dev. of entire data set. If BYCHAN is selected data rescaled using different scaling parameters for each channel. NB. values of 0 and 255 are excluded when determining the statistics used for rescaling. The combined number of 0 and 255's is reported as the number of bad values in the screen output after the first pass.