Aligning geographic data to a known coordinate system so it can be viewed, queried, and analyzed with other geographic data.

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204 views

What method should I use to accurately georeference a geographic map?

I'm writing an application that allows the user to sample points and perform georeferencing In order to test it I have a large scanned map (16k x 13k) pixels covering the area 31 north to 34 north ...
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1answer
30 views

Changing georef backgound colour

Working with a greycale scanned image: when I georef that image it rotates (expected) the blank corners are then filled with black. When the new image overlays I need to make those corners ...
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2answers
127 views

Help, I have 10,000+ .shp files covering 3 UTM zones with unknown projections

I was handed a ton of property files with no projections attached but was told they are all in UTM zone 21S. Well once I merged them all together and projected them I realized that the data covers 3 ...
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1answer
62 views

problem georeferencing a TIFF QGIS

I'm trying to georeference a TIFF in QGIS2.0, 32Bit. The problem appears when QGis adds the map in my project, the map transforms into a black square and it goes to the wrong place. In the next image ...
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1answer
343 views

Georeferencing an image with GDAL, based on QGIS Georeferencer Plugin

I would like to georeference an image with GDAL. The image already has a spatial reference set (EPSG:31276). For the georeferencing, I have a list of 4 ground control points (also in EPSG:31276). ...
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173 views

Making a georeferenced PDF or GeoTIFF from jpg+jgw using GDAL for Avenza PDF Maps

I'm trying to create georeferenced files for the mobile app Avenza PDF Maps. This app works with either GeoTIFF or georeferenced PDF. I know for sure that PDFs made with ArcMap work properly. I'm ...
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1answer
140 views

How can I correct a .pgw file for a PNG image?

I have a PNG file and I need its .pgw file to be set with NAD 83 as the projection. I have created a .pgw file: 799 0 0 -799 -122.562 37.1946 However when I open the PNG in QGIS or ArcMap 10.2 it ...
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1answer
36 views

How can I locate additional GCPs?

I'm a new user of QGIS. I'm georeferencing a scanned image of topographic map. At least 16 GCPs were required for us to locate. However, only 12 can be located and can be identified and be defined ...
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111 views

CartoDB Geocoding Not Working?

I'm using CartoDB to map events on my college campus. First off, I have two tables of data. The first table contains information about the buildings the events can possibly be located within. The ...
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1answer
34 views

Determing which Which georeference system was used on an Ecuadorian Topo Baselayer

I'm creating a map in Western Ecuador, and am attempting to use a military topo baselayer for it. The map comes with UTM grid lines on it so georeferencing it was easy but I'm unsure of what ...
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1answer
189 views

How to plot street addresses and streets using Python/GIS?

I asked this on stackoverflow but did not get a really clear answer. I am not really familiar with GIS systems in python. I am looking for a library to do the following: Lets say I have a pandas data ...
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2answers
292 views

How do I open images georeferenced in ArcMap in QGIS? (.aux.xml)

We have several ArcMap georeferenced images (raster datasets) that we are attempting to open in QGIS without any luck. These are not inside of a geodatabase and are not Arcinfo Binary Grid format or ...
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1answer
85 views

Re-registering a GEOTIFF in qgis

I'm working on some images taken from a UAV over the course of a year. They are OSGB 1936 projection as is the whole project. Annoyingly they don't quite line up so I am trying to a few of the images ...
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1answer
77 views

Why do MGI and WGS 84 data not line up in ArcGIS for Desktop?

When i reproject raster from MGI 6 zone to the WGS84 it makes a mistake (it is moved for 380 m )See example below: I know that the problem is in MGI 6 projection (it is not accurate),but I do not ...
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1answer
66 views

Why do features in QGIS drawn on same datum as Google imagery from OpenLayers move? [duplicate]

I have just started using QGIS. I've loaded the "openlayers" plugin and added a google hybrid layer, which is based off the WGS84 datum to my understanding. Now I create a shapefile and add a new line ...
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0answers
32 views

Shapefile of Israeli sub-districts

is anyone aware of freely available shapefile of Israeli sub-districts? The file I found only contained data at the district level.
3
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2answers
115 views

Geographically georeference image with limited information

It is possible to semi-accurately georeference an image given only the following information? I'd like to do this programmatically. Center point of terrain, Lat/Lng (WGS84) Pitch of camera FOV ...
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1answer
424 views

Convert long/lat to indian grid system

how to convert lat/long coordinates to Indian Grid system? I've googled for a couple of days but didnt find the exact algorithm for this. and i got a link Indian Grid System. but i didnt get a picture ...
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5answers
125 views

Georeferencing a .jpg image

I am having a .Jpg image of a district. I need to georefernce it. The problem is that I can able to find only one control point of it . All other line features (are Roads) which I cant able to match ...
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2answers
206 views

how to georeference my png using gdal

Hello I have created my own fantasy map, I have the map in a full size png and the map broken down into tiles ( with no geo data ) I installed MS4W and tried to use it to get the georeference data ...
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71 views

.svg georeference?

How would I go about taking a layer from AI or Inkscape and importing it into Arc? I've got a vector drawing I want to use and I know I need to georeference it but I'm lost as to how. I also can't ...
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1answer
65 views

How to georeference downloaded map using ArcGIS for Desktop? [closed]

I want to georeference a downloaded map. In the downloaded map there is no graticule but I know the projection which was used to make this map. I also know the the location (x, y coordinates) of ...
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1answer
112 views

Is there a bug in Georeferencing in QGIS 2.0?

I recently updated to QGIS 2.0. But now, when I need to georeference some pictures, I have serious problems. When loading the files to be georeferenced, I can see only a part of it in the window, so ...
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1answer
58 views

Georeferencer plugin will not load in QGIS

I have downloaded and installed QGIS. I would like to georeference an image using the core georeference plugin. When loading it no toolbar appears and the 'update', 'reinstall' etc boxes in plugin ...
0
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1answer
139 views

gdalbuildvrt error, when using in Python

I am new to python/GDAL and am running into perhaps a trivial issue. This may stem from the fact that I don't really understand how to use GDAL properly in python, or something careless, but even ...
4
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1answer
336 views

Direct Georeferencing with X,Y,Z and Omega, Phi, Kappa

I have images taken from plane, it's longitude, latitude, elevation, omega, phi, kappa. I suppose that earth is flat (I don't need any DEM on that stage) and I want to calculate how image is nailed to ...
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1answer
166 views

using GDAL/python to stack georeferenced images of different sizes

I am in the process of porting a code I wrote in IDL (interactive data language) to python but am running into a bit of a problem that I am hoping someone can help me with. The code goes like this: ...
0
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1answer
48 views

Can I export an imagery directly to a geo-referenced raster form File|Export Map in Arcmap?

While using File|Export to export an imagery to raster, is there a way to have it geo-referenced in a way that if I load the exported raster into the map, the image sits exactly in its place without ...
3
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2answers
215 views

Python Script: Automatically georeference photographs (To be used in ArcMap)

I have 563 photographs that have been taken as part of a site survey. The only location information that I have is a single GPS location (lat,long) at which the photograph was taken. I'm looking for a ...
2
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1answer
56 views

How to get a collection of georeferencing control points in an ArcMap document?

I have created control points (i.e. links) using ArcMap's Georeferencing toolbar. How can I programmatically retrieve a list of these points? I'm looking for something like an enum of the links you ...
2
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1answer
97 views

Loading / georeferencing OS rasters in QGIS

I have got some OS rasters but there isn't georeferencing file (TFW) with them. When I try to load them, it will obviously load in the wrong place. They are loading fine in a different GIS software ...
3
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1answer
106 views

What are the set of projections that can be accurately georeferenced using polynomial 2?

Background I'm starting with a map from the internet (Encyclopedia Britannica) and georeferencing it using QGIS 2.0.1, I get really accurate georeference solution using polynomial 2 transformation: ...
2
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0answers
59 views

Using ST_Affine() and trans_param() functions on vector layer

After reading this post How to georeference a vector layer with control points? I decided to give it a try to move/rotation/scale a polygon using Postgis. I have two polygons, polygon_from and ...
9
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1answer
1k views

Is there an explanation of Root-Mean-Square-Error (RMSE) for Dummies available?

Having an all-round expertise in GIS is sometimes not enough to fully understand some concepts of GIS Science. To add to this, I am also not a mathematician. Considering this, would anyone be able ...
1
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1answer
109 views

Why does georeferencing reduce the image resultion?

I'm trying to use a raster as a base image in my QGIS project. It is a building schematic which is fairly high resolution. Importing this into QGIS, it seems that the only way to re-position an ...
1
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1answer
32 views

Georeferenced labeling

I have a problem with ArcMap that somehow affect georeferencing. So I have three layers, two with .lyr and one is a raster data. The two .lyr datatypes are a border and cities with names. I ...
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0answers
18 views

Transformation type - when to use which type? [duplicate]

I am using QGIS 2.0.1 on a Mac, and I am georeferencing a scanned map from 1822. The image is an excellent quality scan, and includes a grid of lat-long. I do not know much else about the map that ...
2
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1answer
166 views

Align and georeference GIS layers exported from CAD

I have two separate CAD files of the same locale. The first one has surface data like street curbs, building footprints, etc. It is not georeferenced, but when I add it to other items in a projected ...
2
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1answer
78 views

Georeference image is mirrored

I'm working with QGIS and I'm trying to geo-reference a tobin lease map. The map datum: NAD27, projection: UTM Zone 14N. The process to georeference is fairly straight forward but the results I'm ...
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2answers
147 views

display GeoReferencing image through MapServer

I have a tiff image and got the world file which contains the needed information for GeoReferenceing, how to start add this image on Mapserver ? if I use C# and use GMAP API to call the google server ...
4
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1answer
83 views

Area calculation of an object without coordinates

I have a photo of an object with a scale and I want to calculate its area. I guess I have to create a polygon of the area to be calculated to use the 'field calculator'. But how do I tell the program ...
0
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1answer
80 views

GeoReference use wordfile in arcgis [duplicate]

I have a tiff image and have the required information to Geo-reference it on the MAP. which called world file like this. using GMAP.NEt API there are many limited functions not like the java script ...
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0answers
52 views

What do you think is happening to my QGIS Georeferencer

I'm pretty new with QGis, but have used tools as Openlayers and Geoserver for some years now without never being asked to diplay a georeferenced raster image. Which gets me to use QGis in order to ...
1
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1answer
443 views

GeoReference tiff image into the Google map?

I want to Geo-reference a tiff image contain a Map for a specific region, I need to add this region(image) and Geo-reference it on the Google map, SO I can see on the map for the region I select the ...
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1answer
81 views

Georeferencing - Arcmap 10.2: Trouble with deleting control points

I'm trying to georeference a raster using a rivers vector (polyline) feature class. I started by shifting and rotating the raster. However when deleting a control point to reduce my RMS, both shift ...
4
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1answer
313 views

Historical U.S.G.S. Georeferencing

I have downloaded a historical USGS map that is suppose to be a geoPDF. My understanding is that QGIS cannot directly read geoPDF's. I have not had any luck in converting it to a geoTIF in order to ...
2
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2answers
367 views

How to import DWG file from CorelDraw to MapInfo project?

I have to make polygons of some protected areas in MapInfo. I have the WMS with the protected areas loaded into mapinfo but making polygons from the WMS will take me years. So I took the following ...
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1answer
81 views

What is the best method to georeference polygons with no spatial reference?

I have a Google earth image which has drawn polygons on it. I would like to create a polygon feature class in ArcGIS using this data. However, the actual image has been manipulated in powerpoint. ...
2
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2answers
84 views

How to adjust data digitized from an erroneously georeferenced basemap?

I have made quite a big georeferencing error, by attributing one of the control points of the map with a value that is 2 km less than the actual value, on the horizontal axis. The georeferenced map ...
2
votes
2answers
224 views

Georeference vector linework

I'm new to GIS and a lot of searching didn't answer my specific question so far, so I hope someone can help me here. What I want to do is creating a small web application to visualize election ...