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      IDRISI Exercise 15 - Georegistration using RESAMPLE

       Make a folder 'PAXTON' in your area and copy all the files with the prefix 'pax', ie Paxcor.cor to Pactxt.vec, in \EXERCISE, to the PAXTON folder.

        Display PAXTON in grey, autoscale; check the x and y and row and column coordinates.
        Run DESCRIBE (in File) PAXTON and check the max and min values.
        Display the vector file PAXROADS, a vector image digitized in UTM coordinates.
        Add a vector layer PAXPNTS with the user defined symbol file set to PAXPNTS, and
 a text layer PAXTXTS with the symbol file PAXTXT.
        Run EDIT and examine the correspondance file PAXCOR containing the X-Y coordinates
 from PAXTON image and the X-Y coordinates from the DLG image (or values digitized from a
 UTM map using a Tablet and TOSCA or AUTOCAD or FIELDLOG).
        Run resample with PAXTON as input PAXRESAM as the output, and PAXCOR as the
 correspondance file. Choose other for the reference system and enter US27TM19,and enter '0'
 as the background value. The number of columns is (MaxX-MinX)/resolution, and the number
 of rows (MaxY-MinY)/resolution. Choose the linear mapping function and click OK. The
 relative error is now calculated. The RMS should be less than half the resolution of
 the input image.


Figure 1. Plate Tectonics.


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