# Krovak Oblique Conic Conformal

Name | Krovak Oblique Conic Conformal
EPSG Code | 9819
GeoTIFF Code |
OGC WKT Name | Krovak
Supported By | EPSG, PROJ.4, OGC WKT

### Projection Parameters

Name | EPSG # | GeoTIFF ID | OGC WKT | Units | Notes
--- | --- | --- | --- | --- | ---
Latitude of projection center | 1 | CenterLat | latitude_of_center | Angular |
Longitude of projection center | 2 | CenterLong | longitude_of_center | Angular |
Azimuth of the center line | 3 | AzimuthAngle | azimuth | Angular |
Latitude of Pseudo Standard Parallel | 4 |  | pseudo_standard_parallel_1 | Angular |
Scale factor on the pseudo standard line | 5 | ScaleAtCenter | scale_factor | Unitless |
False Easting | 6 | FalseEasting | false_easting | Linear |
False Northing | 7 | FalseNorthing | false_northing | Linear |

### Notes

Krovak could be added to PROJ.4 if a CT code was assigned, and some way of transporting the latitude of pseudo standard parallel was assigned.

### Test Point

Given the following Well Known Text definition of a Krovak coordinate system:

    PROJCS["S-JTSK (Ferro) / Krovak",
        GEOGCS["S-JTSK (Ferro)",
            DATUM["D_S_JTSK_Ferro",
                SPHEROID["Bessel 1841",6377397.155,299.1528128]],
            PRIMEM["Ferro",-17.66666666666667],
            UNIT["degree",0.0174532925199433]],
        PROJECTION["Krovak"],
        PARAMETER["latitude_of_center",49.5],
        PARAMETER["longitude_of_center",42.5],
        PARAMETER["azimuth",30.28813972222222],
        PARAMETER["pseudo_standard_parallel_1",78.5],
        PARAMETER["scale_factor",0.9999],
        PARAMETER["false_easting",0],
        PARAMETER["false_northing",0],
        UNIT["metre",1]]

The point `(16d50'59.17"E,50d12'32.44"N)` relative to greenwich maps to `(568991.18mE, 1050538.67mN)` in the projected coordinate system. To avoid the issue of prime meridian add the prime meridian offset to the longitude_of_center.

### PROJ.4 Organization

PROJ.4 has the azimuth, and pseudo standard parallel "hardcoded" to match the common use of Krovak (azimuth = 30.28813972222222, pseudo standard parallel 78.5). Other parameters default to the values in the above test point (with longitude_of_center adjusted for prime meridian).

      +proj=krovak +lat_0=Latitude of projection center
                   +lon_0=Longitude of projection center
                   +k_0=Scale factor on initial line
                   +x_0=False Easting
                   +y_0=False Northing