The process of converting the coordinates of a map or an image from one system to another, typically by shifting, rotating, scaling, skewing, or projecting them.

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16 views

ITRF2008 to WGS84 Datum Transformation in ArcMap?

If I have data in IRTF2008 as shapefile is it possible to change this to WGS84 and how? The need for this comes when trying to display the data in a third party program that doesn't recognize the ...
5
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2answers
106 views

Transformation parameters for Everest datum to WGS84

I have a shapefile with the following projection information: ...
3
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2answers
32 views

Compensating lat/long offsets after conversions

In my application I am doing conversions between two different formats of data. First format is a simple one containing NE and SW coordinates for a given rectangular area: area = { "sw": { ...
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0answers
35 views

“Georeferencing” lidar data to accurate survey

Often I obtain LIDAR data for concept studies and conventional survey (in dxf format) over a small portion of this. The LIDAR typically covers the broader area and is used for broader studies, ...
2
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1answer
52 views

How to export projected layers with relative cartesian (x,y) coordinates in ArcGIS

I've got several GIS datasets for a national park in South Africa (elevation map, water points, elephant density and such). I have access to the full ArcGIS Desktop Advanced suite, but am no GIS ...
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2answers
86 views

ArcGIS Desktop:Transformations: Geographic vs Projected?

Arc10. I have two data sets (both CSV files w/ lat and long columns) and I am working on standardizing them to the same projection. File1: NAD27; File2: NAD27, WGS84, and NAD83. I would like all of ...
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2answers
71 views

Convert a grid file from one set of coordinate systems to another

I have a grid file in a certain coordinate system. I'd like to change it so I have the same grid in geographic lat/long based on WGS84. This seems like something that gdal can tackle quite easily ...
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1answer
39 views

NAD27 to NAD83, saving AFTER transformation?

I need to measure the distance (with the ruler) of points from two different layers. One layer is NAD83 and the other is NAD27. When importing the NAD27 csv file, I specified it was NAD27. Then I ...
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1answer
23 views

Transform from WGS84 to Cylindrical Equal Area

What transformation should I use to go from GCS_WGS_1984 to Sphere_Cylindrical_Equal_Area? I am using Arc to project a dataset over for and area calculation and then will project it back.
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1answer
145 views

Slight translation with coordinate-transformation from Gauss-Kruger to WGS 84. Possible Reasons?

I have a number of points in Gauss-Kruger, Zone 3 that I want to convert to display them within Google-Earth. Assuming WGS84 for Google-Earth the transformed coordinated differ from the original ones ...
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2answers
92 views

Converting coordinates to 4326 for Google Maps.

I have a MultiLinestring, example coordinates, (698745.50201423 4210011.04002000) and I would like to convert them to something like (24.362 42.458) to use in Google Maps. When I try to get the SRID ...
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1answer
76 views

Re-project from Polar projection to EPSG:4326

I simply want to project a polar stereographic raster (EPSG:3411) to Mercator (EPSG:3857) or WGS84 (EPSG:4326). The data I is from NOAA. $gdalwarp -s_srs EPSG:3411 -t_srs EPSG:3857 northpsg.20141027 ...
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1answer
59 views

Double transformation of marker in Carto CSS

I need to show on the map the direction of the road traffic with arrows. For this purpose I use markers for Carto CSS in TileMill. If the road has in OSM tag oneway="yes" or oneway="1", all is ok, ...
2
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1answer
45 views

How to use qgis coordinate transformation in user code

I am now working with coordinate transformations between different CRSs, e.g. latlong to UTM. After comparisons, I found out that the coordinate capture plugin in QGIS is quite accurate for the ...
2
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3answers
64 views

matching coordinate systems by transforming and projecting

matching coordinate systems of all my data (transforming, projecting) My data uses the GCS_Bessel_1841 coordinate system. Would there be any inaccuracies if i would transform it to DHDN 3-Degree ...
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1answer
60 views

Automatically georectify raw Landsat scenes

I am working with 20 raw Landsat images downloaded from GloVis, in WGS 84 (EPSG 32634) coordinate system. I need to geometrically correct them to S_JTSK (EPSG 5514). Usually, georectification is done ...
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2answers
68 views

Tasseled Cap Transformation on MODIS in GRASS

I would like to know how to perform a Tasseled Cap Transformation on MODIS, in GRASS. I've found this https://searchcode.com/codesearch/view/19063909/ but I don't know if this has been tested. I'm ...
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0answers
46 views

Clustering the WGS84 point features (projection transformation aspects)

My question is quite trivial and was discussed many times before (like here) but in our case it has the confounding extra requirements... The list of sparsely distributed 2d point features is stored ...
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0answers
44 views

How use DataFrame Geographic Transformation User Interface with ArcObjects?

I am bringing data from SQL Server into ArcMap with ArcObjects as a Query Layer. If I do this manually, a 'Geographic Coordinate System Transformations' UI pops up. I would like the same thing to ...
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1answer
36 views

Geographic -> UTM Raster Rectification

I'm trying to use an image overlay in KML / Google Earth as the basis for adding extra info and returning this to Google Earth. In my utility app I can specify a rectangle to give me the ...
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2answers
160 views

Transforming and Projecting Shapefiles in R & ArcGIS for Desktop?

Perhaps this is an issue with one of my original data sources, but I've searched extensively to address this problem both through ArcGIS and R. I've got 2 separate sources of a county layer SourceA ...
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35 views

Precision loss when transforming coordinates systems in GDAL (vector layers)

Anybody knows the order of magnitude of the error introduced when transforming coordinates using GDAL? More specifically, I would like to know if significant error is introduced when the ...
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0answers
35 views

Node.js transformation from NAD83 to WGS84

I've used the excellent npm shapefile library to import Canadian electoral districts into MongoDB. Here's a sample file: http://ftp2.cits.rncan.gc.ca/pub/geott/electoral/2011/fed308.2011.zip Is ...
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1answer
94 views

Problem with Converting XY Coordinates to LatLon

Here is the function that I use to convert from pixel x,y to lat,lon coordinate: public static Coordinate imageToWorld(Dataset gds, int x, int y) { double[] adfGeoTransform = new ...
2
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1answer
108 views

PROJ4 / PostGIS transformations between WGS84 and NAD83 transformations in Alaska

I'm trying to implement the recommended WGS84 - NAD83 transformation for Alaska using PostGIS. This post: Geographic Transformations in Alaska Between NAD83 and WGS84 indicates the proper ...
2
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1answer
51 views

Distort image to display on leaflet.js based on known 16x16 point grid

I have an image that is a satellite picture, and with php gd I want to distort it so I can overlay it on a leaflet.js map. To make it a bit more simple, I have a grid of points, 16x16 which bind the ...
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2answers
187 views

Mercator: scale factor is changed along the meridians as a function of latitude?

"In Mercator projection the scale factor is changed along the meridians as a function of latitude" How to calculate the Mercator scale factor as a function of the latitude in decimal degrees ? ...
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0answers
64 views

Offset WGS84 linestring based on pixel values

I would like to split up some roads based on their driving direction. For this, I need to offset the roads 2 pixels to the right, in the direction of the linestring. I have the coordinates in WGS84 ...
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0answers
34 views

Geodjango transform introduces large errors

Apologies for the possibly naive question. I'm trying to understand how Geodjango (running on PostGIS) deals with coordinate transformations, and am experiencing some unusual behaviour. Let's say I ...
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1answer
63 views

Why are my points being flipped or mirrored when I convert from DMS to DD?

I have a collection of crash data that provides latitude and longitude in degrees, minutes, and seconds that I'm converting to decimal degrees using: (degrees + (minutes/60.0) + (seconds/3600.0)) ...
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1answer
143 views

Translate coordinates in GeoJSON export

I am wondering if there is a way to apply a translation in coordinates for a GeoJSON export. Currently, there are negative coordinate values in my export, which I cannot have. I am trying to use ...
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2answers
67 views

Accurate local map projections

Is there a map projection that can accurately represent reality at a local area, i.e. when transforming the map could I choose an area that I care about accuracy and allow distortions elsewhere? Like ...
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0answers
26 views

EPSG1612 transformation [closed]

I have survey data for contacts listed as eastings and northings - I need to overlay this onto PNG files but the location is quite far north - How do I apply EPSG 1612 transformation to the UTM Zone ...
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1answer
95 views

Rotating markers for points in Tilemill along direction of a way

I have designed a simple marker to represent pedestrian crossings, which in OpenStreetMap data are represented as nodes (points) along the way (line). I want to rotate the marker to follow the line it ...
5
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1answer
161 views

Moving a shape around the earth while maintaining the proper projection

What is the transformation needed to be taken on every data point of a shape to rotate that shape around the globe. I'm trying to figure out the math behind this kind of transformation so I can ...
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2answers
55 views

How to set a coordinate transformation GRID

Does anyone know how to set a coordinate transformation in qgis so I can measure the distances in meters or kilometers? If anyone has a clue, would be just great. Thanks!
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2answers
92 views

Any difference between EPSG:3003 and EPSG:102091?

I am working on QGIS 2.2.0. The PRS I am working on is Monte Mario / Italy zone 1 (EPSG:3003), with the following parameters: PROJCS["Monte Mario / Italy zone 1", GEOGCS["Monte Mario", ...
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1answer
90 views

Shifting a CAD file from ATS77 MTM 5 to NAD83 CSRS UTM 20

Looking to make the coordinate system shift in ArcMAP (for Nova Scotia) between ATS77 MTM 5 and NAD83 CSRS...NTv2 file?
3
votes
1answer
97 views

Help with “projected XY to screen xy” conversion algorithm?

I'm trying to convert coordinates from any given coordinate system (be they the coordinates of a graph figure or a map, meaning they can span across both negative and positive values across any of the ...
0
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1answer
85 views

Find AB_CSRS.gsb for NAD_1983_TO_WGS_1984_8 Transformation

I am trying to change my WGS84 data to NAD83 for Alberta data. My research tells me that I need to use the NAD_1983_TO_WGS_1984_8 Datum Transformation which is in the AB_CSRS.gsb. I can not find this ...
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1answer
83 views

Can I define a transformation between 2D and 3D in Geotools?

I'm using Geotools, and I need to convert coordinates between 2D and 3D coordinate reference systems. I recognize that there's no universally-correct way to do this: 2D -> 3D means "making up" a Z ...
0
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2answers
114 views

Defining a scale number from the Helmert transformation

I know this is more bit of a cartographic issue, but maybe somebody would be able to help. I have an old map georeferenced to the openstreetmap with 50 identical points. I want to get the scale of the ...
2
votes
2answers
59 views

How to replicate ArcGIS coordinate transformation with ogr2ogr?

I need to be able to replicate with ogr2ogr a coordinate transformation that was executed in ArcGIS for Desktop. Both ArcGIS and ogr2ogr are based on EPSG standard definition. There's not only one ...
2
votes
1answer
65 views

ArcGIS: How to affect graphics in a MXD by a geographic transformation?

Our GIS users have been using graphics to mark things in their map documents. By graphics, I mean circles, rectangles, lines, text, etc. that can be drawn into data view by using the Draw toolbar. We ...
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1answer
172 views

Rotating the coordinates of a layer by 90 degrees

I have got a dwg file with the plans for a building, with rooms and everything. (There's been some samples taken inside the building which I want to display.) Now, since it's of a building, the person ...
2
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2answers
88 views

How do I transform a raster image to one with rounded corners (cylindrical to pseudocylindrical)?

I've been working with the altimetry data from topex.ucsd.edu/WWW_html/mar_grav.html Was having difficulties extracting the data, so I wrote a simple tool to do that. Creates a bitmap form the data ...
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2answers
845 views

Convert geometry to latitude-longitude using PostGIS ST_Transform

My table has a geometric field, in EPSG:3857, of type point. I need the latitude and longitude, in EPSG: 4326, of each point. Could someone give me a valid example of how to use ST_Transform().
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0answers
46 views

WGS 84 Transformation issues with ArcGIS and Global Mapper

I have rasters, need to be geo-referenced in WGS 84 datum with Lat/Log (degree). I have geo-referenced using Global Mapper, which we usually used to use, because of its user friendly. Got a vector ...
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2answers
60 views

Transform coordinates from NOAA

I use data from NOAA for some analysis in R and I want to transform coordinates to EPSG:54004 or something useful. There is something what they write about their coordinates. ... POS: 29-34 ...
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1answer
49 views

How to resolve a 'Received NULL pointer' ArgumentOutOfRangeException for OSGeo.OGR.Geometry.TransformTo?

I am attempting to project a geometry using the GDAL c# bindings and I'm getting a ArgumentOutOfRangeException ('Received NULL pointer') exception on the Transform methods of Geometry. I'm also ...