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[Jorgeee]

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I have some .map OZI calibrated maps. From those .map, I can get some calibration points (x y in the jpeg picture + lon lat in WGS84).

MMPXY,1,142,142

MMPXY,2,5217,142

MMPXY,3,5217,3422

MMPXY,4,142,3422

MMPLL,1,  -0.269639,  39.626293

MMPLL,2,  -0.186306,  39.626293

MMPLL,3,  -0.186306,  39.584626

MMPLL,4,  -0.269639,  39.584626

With that I build a coordinates file

-0.269639  39.626293 (142,142)

-0.186306  39.626293 (5217,142)

-0.186306  39.584626 (5217,3422)

-0.269639  39.584626 (142,3422)

From the .map file I can also know that the map projection is UTM

Map Projection,(UTM) Universal Transverse Mercator,PolyCal,No,AutoCalOnly,No,BSBUseWPX,Yes

With proj4 I get the projection of those points in UTM

$ proj +proj=utm +ellps=WGS84 coord

734345.05	   4389843.39 (142,142)

741498.53	   4390064.29 (5217,142)

741643.45	   4385438.93 (5217,3422)

734485.67	   4385218.08 (142,3422)

The goal is knowing a pair of coordinates in the map (for instance -0.269058 39.599662), get the x y pixel in the map.

$ proj +proj=utm +ellps=WGS84

-0.269058 39.599662

734484.83	   4386888.69

How can I calcultate the X Y pixel for those coordinates having all this data? Am I in the right way

Thank you very much