NEWGCP

Update GCPs with transformation


EnvironmentsPYTHON :: EASI
Quick linksDescription :: Parameters :: Parameter descriptions :: Details :: Example :: Related

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Description


Reads a ground control point (GCP) segment from a PCIDSK file and extracts the forward and inverse transformations. These transformations are then used to calculate a new set of GCPs, which will be placed in the output file. Normally, IMGFUSE is used to automate the entire fusion process.
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Parameters


Name Type Caption Length Value range
FILI * String Input file name 1 - 192  
DBSEG * Integer Input segment number 1 -    
DBSN * String Output segment name 1 - 8  
DBSD String Output segment description 0 - 64  
FILO * String Output file name 1 - 192  
REPORT String Report mode 0 - 192 Quick links
MONITOR String Monitor mode 0 - 3 ON, OFF
Default: ON

* Required parameter
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Parameter descriptions

FILI

Specifies the name of the PCIDSK file that contains the transformation segment.

DBSEG

Specifies the number of the transformation text segment from the input file (FILI).

DBSN

Specifies a name (up to 8 characters) for the output GCP segment.

DBSD

Describes (in up to 64 characters) the contents or origins of the output GCP segment.

FILO

Specifies the name of the PCIDSK file to receive the new output GCP segment.

REPORT

Specifies where to direct the generated report.

Available options are:

MONITOR

The program progress can be monitored by printing the percentage of processing completed. A system parameter, MONITOR, controls this activity.

Available options are:

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Details

NEWGCP reads a ground control point (GCP) segment from a PCIDSK file and extracts the forward and inverse transformations. NEWGCP is mainly used to create a new GCP segment that will allow a transformation of the image with REG.

NEWGCP loads in the forward and backward transformation matrices. The new GCP points are then saved to a GCP segment in the output file (FILO). Currently, only the backward transformation matrix is used. Using REG and specifying the new GCP segment, the image may be transformed back to its original coordinates.

NEWGCP expects to read in a text segment with the 3x3 transformation matrices in the following order:

This function should be used with TRANSFRM to convert the text segment (DBSEG) used in NEWGCP to the correct format.

Typically, IMGFUSE is used to automate the entire fusion process.

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Example

Using text segment number 7 (DBSEG) generated by TRANSFRM and placed in FILI (p2.pix), calculate the new GCPs to perform a backward transformation. Save the new GCP segment in eltoro.pix, in a new segment.

EASI>FILI	=	"p2.pix"
EASI>DBSEG	=	7	! use text segment 7 
EASI>DBSN	=	'GCP_seg'	! new GCP segment name 
EASI>DBSD	=	'GCP segment to inverse transform this image'	! segment description
EASI>FILO	=	'eltoro.pix'	! file to receive new GCP segment

EASI>RUN NEWGCP

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