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PROJ - Cartographic Projections and Coordinate Transformations Library
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missing EPSG 5514 #233

Closed proj4-bot closed 7 years ago

proj4-bot commented 9 years ago

Reported by martinl on 15 Apr 2014 21:58 UTC Hi all,

I discovered that EPSG:5514 is not included in epgs file:

<5513> +proj=krovak +lat_0=49.5 +lon_0=24.83333333333333 +alpha=30.28813972222222 +k=0.9999 +x_0=0 +y_0=0 +ellps=bessel +towgs84=589,76,480,0,0,0,0 +units=m +no_defs  <>
# S-JTSK / Krovak East North
# Unable to translate coordinate system EPSG:5514 into PROJ.4 format.
#
# S-JTSK/05 / Modified Krovak
# Unable to translate coordinate system EPSG:5515 into PROJ.4 format.
#
# S-JTSK/05 / Modified Krovak East North
# Unable to translate coordinate system EPSG:5516 into PROJ.4 format.
#
# CI1971 / Chatham Islands Map Grid
<5518> +proj=tmerc +lat_0=-44 +lon_0=-176.5 +k=1 +x_0=350000 +y_0=650000 +ellps=intl +towgs84=175,-38,113,0,0,0,0 +units=m +no_defs  <>

Does anyone have idea what could be wrong? Thanks in advance, Martin

Migrated-From: https://trac.osgeo.org/proj/ticket/233

zimmicz commented 9 years ago

Hi, any progress on this since reporting?

rouault commented 9 years ago

It is available In proj 4.9, with the same definition as EPSG:5513. I wouldn't exclude there might be an issue with axis order and value signs. This is so confusing.

krticka commented 8 years ago

Well, we in Czech republic and Slovakia are little bit complicated, but here is some explanation.

EPSG code 5514 S-JTSK / Krovak East North is an equivalent to the existing ESRI code 102067. The projection keeps the mathematic so called "east-north" orientation of coordinate axis where the X axis has positive values eastwards and Y axis northwards. This projection is suitable for exploitation in GIS applications. The projection is related to the Greenwich Prime Meridian (contrary to the EPSG 5221 S-JTSK (Ferro) / Krovak East North where the Prime Meridian is Ferro). Specific is, that grid origin is located somewhere between Tallin and Helsinki (northeast of Czech and Slovakia), what means that values of X,Y are always negative in area of Czechia and Slovakia in 5514. Here is WKT for 5514 from EPSG 8.7.5:

PROJCRS["S-JTSK / Krovak East North", BASEGEODCRS["S-JTSK", DATUM["System Jednotne Trigonometricke Site Katastralni", ELLIPSOID["Bessel 1841",6377397.155,299.1528128,LENGTHUNIT["metre",1.0]]]], CONVERSION["Krovak East North (Greenwich)", METHOD["Krovak (North Orientated)",ID["EPSG",1041]], PARAMETER["Latitude of projection centre",49.5,ANGLEUNIT["degree",0.01745329252]], PARAMETER["Longitude of origin",24.833333333333,ANGLEUNIT["degree",0.01745329252]], PARAMETER["Co-latitude of cone axis",30.288139722222,ANGLEUNIT["degree",0.01745329252]], PARAMETER["Latitude of pseudo standard parallel",78.5,ANGLEUNIT["degree",0.01745329252]], PARAMETER["Scale factor on pseudo standard parallel",0.9999,SCALEUNIT["unity",1.0]], PARAMETER["False easting",0,LENGTHUNIT["metre",1.0]], PARAMETER["False northing",0,LENGTHUNIT["metre",1.0]]], CS[cartesian,2], AXIS["easting (X)",east,ORDER[1]], AXIS["northing (Y)",north,ORDER[2]], LENGTHUNIT["metre",1.0], ID["EPSG",5514]]

Correct definition for 5514 (with transformation key) should be: +proj=krovak +lat_0=49.5 +lon_0=24.83333333333333 +alpha=30.28813972222222 +k=0.9999 +x_0=0 +y_0=0 +ellps=bessel +pm=greenwich +units=m +no_defs +towgs84=570.8,85.7,462.8,4.998,1.587,5.261,3.56

NOTE: several other transformation keys (+towgs84) exist, but this one above is approved by Czech State Administration of Land Surveying and Cadastre.

The difference for 5513 S-JTSK / Krovak is that X axis has south orientation and Y axis has west orientation (axis are switched). This coordinate reference system is used in land surveying but is not suitable for use in GIS applications due to the unusual orientation of the coordinate axes. Here is WKT for 5513 from EPSG 8.7.5 to see the difference:

PROJCRS["S-JTSK / Krovak", BASEGEODCRS["S-JTSK", DATUM["System Jednotne Trigonometricke Site Katastralni", ELLIPSOID["Bessel 1841",6377397.155,299.1528128,LENGTHUNIT["metre",1.0]]]], CONVERSION["Krovak (Greenwich)", METHOD["Krovak",ID["EPSG",9819]], PARAMETER["Latitude of projection centre",49.5,ANGLEUNIT["degree",0.01745329252]], PARAMETER["Longitude of origin",24.833333333333,ANGLEUNIT["degree",0.01745329252]], PARAMETER["Co-latitude of cone axis",30.288139722222,ANGLEUNIT["degree",0.01745329252]], PARAMETER["Latitude of pseudo standard parallel",78.5,ANGLEUNIT["degree",0.01745329252]], PARAMETER["Scale factor on pseudo standard parallel",0.9999,SCALEUNIT["unity",1.0]], PARAMETER["False easting",0,LENGTHUNIT["metre",1.0]], PARAMETER["False northing",0,LENGTHUNIT["metre",1.0]]], CS[cartesian,2], AXIS["southing (X)",south,ORDER[1]], AXIS["westing (Y)",west,ORDER[2]], LENGTHUNIT["metre",1.0], ID["EPSG",5513]]

How is change of axes handled in Proj4? Should it be +x_0=-0 +y_0=-0 for EPSG 5513?

rouault commented 8 years ago

How is change of axes handled in Proj4? Should it be +x_0=-0 +y_0=-0 for EPSG 5513?

No, but you likely can achieve thatwith the +axis= parameter : https://trac.osgeo.org/proj/wiki/GenParms#Axisorientation

krticka commented 8 years ago

Hi, I made several test with 5513 data, but it seem that +axis parameter is not working in my software (QGIS). I tested it also in ArcGIS and data are still drawn with wrong orientation (comparing to display of data in Groma which is software used by surveyors and where 5513 is correctly configured). Can you recommend any software which is able to work with +axis= parameter?

krticka commented 8 years ago

So, 5514 definition mentioned above is OK. 5513 I discussed at work with colleagues (cartographers). The axis orientation in 5513 is very specific (positive values are in 3rd quadrant of Cartesian coordinate system) and most of the GIS software will not display data correctly oriented as common software is programmed to use classic Cartesian coordinate system. I don't know if there is any possible workaround for proper display in common GIS software like QGIS or ArcGIS is, but true is that 5513 is used only by surveyors working with cadastral data where specific software is used. My recommendation for next release is to leave 5513 as it is defined and just add definition for 5514.

Anyway here I attach two files with points (CSV format): sample_points_5513.txt - XY coords in EPSG 5513 and BLh for ETRS89 sample_points_5514.txt - same points, but XY coords in EPSG 5514

sample_points_5513.txt sample_points_5514.txt

dg0yt commented 8 years ago

Where shall a pull request for changing 5513 be submitted to: proj.4 or gdal? IIUC proj uses EPSG data generated from gdal.

kbevers commented 7 years ago

I guess this has been partially fixed, although I agree there's still a problem regarding the axis. If it is at all possible to fix with the current infrastructure in proj, it is probably best solved in the EPSG overrides in libgeotif and not here.