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

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2
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0answers
96 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
votes
1answer
3k 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
vote
1answer
175 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
vote
1answer
35 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 ...
2
votes
1answer
348 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
votes
1answer
121 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 ...
2
votes
2answers
244 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
votes
1answer
99 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
votes
1answer
115 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 ...
1
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0answers
55 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
vote
1answer
808 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 ...
1
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1answer
134 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
votes
1answer
370 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
votes
2answers
695 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 ...
1
vote
1answer
123 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
votes
2answers
118 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 ...
3
votes
2answers
557 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 ...
2
votes
1answer
125 views

How to determine if an image file is georeferenced

I have a task to scan a folder for georeferenced images. There might be a lot of images, some quite large, and some not georeferenced. The spatial information can also be either embedded or in a world ...
2
votes
1answer
363 views

Problem with georeferencer in Qgis 2 64bit installation

I tried to use the georeferencer in the new Qgis 2 64 bits for windows. I tried with the standallone installer and with the OSgeo4w installer. The problem is when I load the raster that I want to ...
1
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2answers
379 views

Merging many map sheets together into one large sheet for later georeferencing?

I have hundreds of images, each one is a scan of a map sheet, and I want to georeference them. The maps cover a large area (a whole country), they just split the area into many smaller cells. Each map ...
2
votes
1answer
290 views

QGIS Georeferencer, unexpected transformation, and GCP placement

Im trying to get the sample map which i believe to be EPSG:3112 into QGIS and geo referenced. In my screenshot, on the right is the raster in georeferencer with the points i have added. On the left is ...
2
votes
3answers
265 views

Batch rectifying 200+ historic aerial images?

I have acquired historic aerial imagery for the surrounding towns, circa 1954, and the images have no georeference. I am looking for software to help me batch-rectify the 200+ images. I have current ...
1
vote
1answer
236 views

How to link 2 different images in eCognition

I'd like to link 2 different images in eCognition to find the same pixels on both images. The images have same projection (geog lat/long). How can I do this? Thank you so much
1
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0answers
260 views

Georeference to UTM projection using openlayers plugin in QGIS

I have some aerial imagery that I need to georeference using QGIS into a UTM projection. In order to do this I need a basemap layer for the reference points. The openlayers plugin could work great ...
1
vote
2answers
385 views

How to georeference a raster based on identical, already georeferenced raster

I have two identical rasters, one has been georeferenced, the other has not. I would like to georeference the second raster automatically using the first one. I do not want to create links by hand and ...
1
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0answers
55 views

QGIS: georeferencing report: tail cutted off

I'm using QGIS 1.8.0-2 to georeference some old maps and want to report residuals and other information via the PDF report function of the Georeferencer tool. If there's too much information, it's cut ...
1
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2answers
287 views

QGIS:what does it do “snap gcp coordinates to background layers” in the Georeferencer plugin?

Maybe is too obvious, but I don't find any precise documentation about this checkbox in the georeferencer plugin.
0
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0answers
69 views

How to create a raster from a CAD scan for ARCMap?

I have scans of CAD streets and such and want to get a raster for georeferencing into ARCMap. What are the easy steps to make a targa, geotiff, etc. of a known size, say 2 miles along one side as a ...
1
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0answers
45 views

Georeferencing a Picture having Resolution and a nearly correct BBOX

Is it possible to get the Boundingbox of a Picture when I know the Resolution, the Height/width in pixels, the sum of Tiles in each row/column and a Coordinate that is in the cornertile but not the ...
1
vote
1answer
579 views

Specify world file to use in ArcGIS

I have a BMP file where I know the coords of the corners, and hence have a generated a World File according to ESRI's standards. It has the the right filename, but when I add the image in ArcMap, it ...
2
votes
1answer
583 views

How to align (georeference) images using QGIS?

I'm completely new to all this. I'm trying to make a map of Han dynasty-era China for a mod for a game called Crusader Kings 2. I've downloaded QGIS and Natural Earth 2, but I need this image to ...
1
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1answer
332 views

How to get bounding box coords?

How to get coords for NW and SE if we have about 4-5 pixels on the image with assigned latit/longit? I'm working on javascript app which would overlay that image on Google Map then. Thanks.
0
votes
2answers
527 views

Calculation for conversion of Lat/Lon to World Geographic Reference System (GEOREF)

Does any one have a reference to, or the actual code, to convert Lat / Lons to Georef code (http://en.wikipedia.org/wiki/Georef)? I am also interested in finding a conversion from lat/lon to MGRS. ...
-3
votes
1answer
462 views

How can I open georeferenced ArcMap raster files in Qgis?

How can I open georeferenced arcmap raster files in Qgis?
1
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0answers
995 views

Create a jgw file for jpg image.

I converted ecw file into jpg file with IrfanView, to display the jpg as base layer in openlayers. I understood that I need to create a jgw file to display the jpg file. I found this example: ...
2
votes
1answer
284 views

Geoserver: Georectification via SLD fails

Situation I have a raster image and the coordinates of its four corner pixels. My goal is to warp the image with respect to this coordinates ("georectify") on the fly when requested via GeoServer to ...
0
votes
1answer
184 views

converting grid references to long/lat

If I import from a POST DB a set of points that are referenced by grid reference, will the long/lat decimal also be added to the file? or will I have to convert the points to long/lat myself? In ...
2
votes
1answer
390 views

Orthophoto in QGIS to georeference for use in Sketchup 8, or how to match it with Sketchup 8 pictures?

I have a high resolution orthophoto of an area I want to rebuild in sketchup and therefore want to lign it up (georeference it properly), but all the scaling and everything I tried so far did not help ...
7
votes
2answers
730 views

How to Georeference Photos With No Spatial Reference?

I have about 100-200 field ground shot photos I would like to overlay in ArcGIS 10 that have no spatial information which I need to somehow develop using a photogrammetric formula. The camera was ...
2
votes
2answers
341 views

What is causing this distortion in QGIS georeferencer results?

When importing a JPG map using QGIS's georeferencer plugin, the resulting map layer is distorted and does not look anything like the map that I am trying to import. I can't work out what is causing ...
1
vote
2answers
54 views

Cannot See Georeferencer Results

I am working in QGIS 1.8.0 Lisbosa. Currently I am trying to georeference a building blueprint in a .TIF format to a Google Streets layer. After selecting four points (the corners of the building), I ...
1
vote
2answers
542 views

Georeference IMG file in QGIS

I have a problem: I'm trying to georeference a satellite image (ASTER, ERDAS Imagine file *.img) in QGIS. I have georeferenced with QGIS before and never had any problems. The file is georeferenced ...
1
vote
5answers
427 views

Create world file from kml

I have a KML file for a NASA image. I want to create a world file from it so I can use the image in say QGIS. Is it possible to extract the key info (bounding coordinates) from the KML? It seems to be ...
1
vote
2answers
5k views

How to add georeferenced TIFF to AutoCAD 2010

I have a ~6GB georeferenced (from ArcGIS) .TIFF satellite image that a colleague wishes to add to AutoCAD 2010. He wants it as a base layer for digitising features from. I have searched forums but ...
1
vote
1answer
165 views

Worsened image quality and false colours after georeferencing

When I georeference a map of vegetation types (about 20 colours, each representing a certain vegetation) the quality of the georeferenced map is really bad and some colours have changed (e.g. black ...
11
votes
1answer
391 views

Assign projection to a satellite image

Today I stumbled upon a picture taken from the ISS looking down Europe and it is really beautiful. So, I started thinking I could add more to the picture. Like world borders, cities, road network, ...
3
votes
2answers
335 views

How to create georeferenced and projected data from hand-drawn map?

I am preparing datasets for students in a spatial statistics course for a module on spatial autoregressive models. We will use ArcGIS 10.1. The first dataset will correspond to a mythical ...
1
vote
0answers
58 views

how to get correct geo reference system for a VMap

I am new to GIS, trying to read the GeoRef System for VMap by using the following code: OGRSpatialReference *ref = layer->GetSpatialRef(); if( ref ) { QString georefSystem = ...
5
votes
1answer
481 views

Georeferencing a jpeg in QGIS but the scale is way off

I've gone through the really helpful walk-through(s) of how to georeference a jpeg in order to make it a layer, but after inputting the coordinates (either by typing in actual coordinates or clicking ...
1
vote
1answer
180 views

No clue of the Georeferencing tool in gvSIG

I have kept trying to locate the georeferencer in gvSIG but I could not find it. Some tutorials say it is under Tools from the main menu! I installed several versions of gvSIG, both on Windows and ...