Creation of digital catalog of theoretical coordinates

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The digital catalog of theoretical coordinates is created in any text editor before start of the task of a raster map's transformation. Name of a file is any one, extension - *.cat.

For transformation by elements of external orientation the digital catalog of theoretical coordinates of control points prepares or in rectangular coordinates in Gauss-Kruger system and has the following structure:

.CAT

// comment

.GAU

N1 X1 Y1 H1 P1

N2 X2 Y2 H2 P2

.............................

Nm Xm Ym Hm Pm

.END

where .CAT - a  file label (obligatory field),

// - the beginning of a comment line (allowable not obligatory field),

.GAU - system of coordinates: rectangular in Gauss-Kruger's meters (not obligatory field, is accepted by default),

N1 - Nm     - numbers of control points of a raster (an obligatory field - only numerical values),

X1 - Xm - theoretical coordinates of control points in the preset system

Y1 - Ym - coordinates in meters (an obligatory field),

H1 - Hm - absolute heights of control points in meters (not obligatory field, at absence the height is taken equal 0).

P1 - Pm -  attribute of a point (optional field - if there is no attribute, then this is a support point, if there is (for example, k), then this is a control point)

.END - the end of file (an obligatory field).

 

Example:

.CAT

.GAU

93  4209313  4760341  110

94  4210165  4735384  40

96  4234801  4756883  470

97  4242453  4754669  140        

98  4238530  4742974  220 k

99  4247273  4740893   10

.END

or in geodetic coordinates in degrees, minutes, seconds also has the following structure:

.CAT

// comment

.GMS

N1 BG1 BM1 BS1 LG1 LM1 LS1 H1 P1

N2 BG2 BM2 BS2 LG2 LM2 LS2 H2 P2

....................................................………

Nn BGn BMn BSn LGn LMn LSn Hn Pn

.END

where .CAT - a file label (an obligatory field),

// -  the beginning of a comment line (allowable not obligatory field),

.GMS - system of coordinates: geodetic in degrees, minutes, seconds (an obligatory field if such coordinates are set),

 

N1 - Nn  - numbers of control points of a raster (an obligatory field - only numerical values),

BG1 - BGn - latitude: degrees,

BM1 - BMn - minutes,

BS1 - BSn  - seconds,

LG1 - LGn  - longitude: degrees,

LM1 - LMn  - minutes,

LS1 - LSn   -  seconds (obligatory fields),

H1 - Hn - absolute heights of control points in meters (not obligatory field),

P1 - Pm -  attribute of a point (optional field - if there is no attribute, then this is a support point, if there is (for example, k), then this is a control point)

.END - the end of file (an obligatory field).

 

Besides for airphotos the digital catalog of theoretical coordinates of control points can prepare in coordinates in local rectangular system. The structure of the catalog coincides with structure of the catalog for rectangular coordinates:

Example:

.CAT

9 914428.149 512212.611 68.888

10 912384.461 512180.811 74.138

12 914474.583 510180.487 77.049

13 912539.245 510296.721 81.427 k

14 913643.121 511195.588 76.307

.END