MBUSIG -- DIPIX Format Tape Signature Transfer

Reads a signature file from an R-stream Dipix BU tape and creates a new signature segment on a PCIDSK database file.

PARAMETERS

MBUSIG is controlled by the following global parameters: 

Name     Prompt                                  Count     Type
BUFILE   DIPIX Filename                          1-13      Char
FILE     Database File Name                      1-64      Char
DBSN     Database Segment Name                   1-8       Char
VALU     Grey-level Value List                   1         Int
THRS     Gaussian Threshold                      0-1       Real
BIAS     Class Bias                              0-1       Real

BUFILE

Specifies the name of the file to be read. MBUSIG will read only one BU file per run. The filename input should be of the form: 

 Character:         1 2 3  4 5  6 7 8 9  10 11 12 13
 Contents:          (A A A)(M S)(C C C C)(. M S F)
Characters 1 through 3 specify a Dipix area name. Characters 4 and 5 specify the type of file type (MS). Characters 6 through 9 specify a Dipix signature name. Characters 10 through 13 specify the file extension, which is normally .MSF for signature files. If the file extension is not specified, it defaults to ".MSF". 

 EASI>BUFILE="...string..."

FILE

Specifies the PCIDSK file to which to write signature segment data. 

 EASI>FILE="file_spec"

DBSN

Specifies a 1 to 8 character name that will be assigned to the database signature segment. 

 EASI>DBSN="project "

VALU

Specifies an integer value (1 to 254) that will represent the class in the output classification theme map created by MLC. 

 EASI>VALU=n
Values of 0 and 255 are invalid, as they will be used as the null and overlap classes respectively in the output theme map.

THRS

Specifies the Gaussian feature-space threshold. The greater this value, the larger the hyperellipsoid or parallelepiped in feature space. THRS is a REAL number in units of standard deviation. 

 EASI>THRS=n                    
 EASI>THRS=                     | defaults to 3.0

BIAS

Specifies the BIAS or relative "a priori" probabilities for the class. If all classes have equal bias, their a priori probabilities are equal. BIAS `biases' the maximum-likelihood classifier's assignment of a class to a point that lies in overlapping classes in feature-space. BIAS is a REAL number. 

 EASI>BIAS=nn.nn
 EASI>BIAS=                     | defaults to 1.0

DETAILS

MBUSIG reads a signature file (BUFILE) from a Dipix BU tape and writes it to a new PCIDSK signature segment on a PCIDSK database file (FILE). A 1 to 8-character identifier (DBSN) must be specified for the signature segment.

The signatures threshold (THRS) and bias (BIAS) may be specified in real values. THRS defaults to 3.0, and BIAS defaults to 1.0. An integer value between 1 and 254 that will represent the class corresponding to the signature in the output theme map created during classification must be specified using VALU.

The desired signature file name can be determined using the MBUREP program. All signature files have the file extension MSF.

The Dipix BU file name is stored in the segment history record upon completion of the data transfer.

MBUSIG only reads ONE signature file in per run. So if you want to read `N' signature segments from the tape, you must run MBUSIG `N' times, setting the appropriate parameters.

A description of the Dipix tape format is given in the documentation for the MBUREP program. 

 A TAPE MUST BE MOUNTED ON THE TAPE DRIVE BEFORE MBUSIG CAN BE
 RUN.  CLEANING THE TAPE HEADS IS RECOMMENDED TO MINIMIZE THE
 CHANCE OF TAPE READ ERRORS.

EXAMPLE

Transfer a signature file from a Dipix BU tape to the database. Default the signature's threshold to 3.0 and its bias to 1.0. A grey-level value of 64 is assigned to all pixels classified using this signature: 

 EASI>BUFILE="ATBMSALL1"
 EASI>FILE="ATBMSALL.PIX"
 EASI>DBSN="Lakes"
 EASI>VALU=64
 EASI>THRS=
 EASI>BIAS=
 EASI>RUN MBUSIG
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