Raster is a data format consisting of regular grids of values, usually stored in an image-like format.

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774 views

How to write raster field values into attribute table using ArcPy?

Is it possible to use ArcPy (10 or 10.1 )to write raster field types into a featureclass? either SDE or filegeodatabase?. I'm hoping to use arcpy as means of automating the process of adding rasters ...
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5answers
655 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 ...
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1answer
1k views

How do I combine many ECW files in MapInfo?

I have MapInfo 11.5.0.16 (I don't have ArcGIS) and I am trying to combine (in some sense) a large collection of ECW files. I can load one ECW at a time in MapInfo but I have very many. MapInfo ...
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1answer
771 views

GetCapabilities Request for WMS

I'm trying to connect to a WebMapServer with the Geotools WMS classes. My problem is, that the resonse-object "capabilities" doesn't contain all layers. When I'm doing the request in a browser, I can ...
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1answer
443 views

Difference in raster size using raster2pgsql

I use the PostGIS-build-in raster2pgsql to load SAGA-raster into the db. I tried to grid them into 100x100-tiles, just as seen in the code: /usr/lib/postgresql/9.2/bin/raster2pgsql -s 32632 -a -F -...
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1answer
107 views

BIOMOD Error message: argument of length 0

I’m using the package BIOMOD in R to modelling habitat in rodent species. The data formatting works but I'm getting this error message when I run Modelling: ## Conputing the models ## ...
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1answer
240 views

Scanned Transparent Map Overlay

We have a flat file of 50 Geology maps that have a transparent overlay with faults and drill holes. I have them scanned and georeferenced as TIF images and they will be used in ArcGIS 10.0, 10.1 and ...
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1answer
779 views

What are Bands, Dimensions, and Histograms in QGIS?

First; I can see a band as synonymous with a channel in an image editing program like GIMP, is this correct? If so then bands play the role of color mixing and masking. Are there any other ...
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1answer
152 views

Problem loading raster to PostGIS using QGIS

I am having trouble loading a raster (.asc) file to PostGIS 2.0.1 using the plugin Database - PostGIS Raster - Load raster to postgis in QGIS 1.8.0 on Win Vista 64 bit. I get the following error ...
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1answer
281 views

Qgis - Raster clip Problem

I tried to use the Raster (Extration) tool "clipper" and I always get this error log: What is my problem? Fehler bei der Ausführung von Python-Code: Traceback (most recent call last): File "C:/...
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1answer
124 views

Sextante (SAGA) “Normalisation” problem

I don't understand the SAGA-module "NORMALISATION". In SAGA Gis I just can define one MIN and one MAX value. In QGis I have to define 2 of both. How to handle that exactly?
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2answers
271 views

Put color for raster data(aspect.tif) on QGIS1.8.0

I create aspect.tif from DEM file. I could put the values(0 to 360)from contrast enhancement. I could set color from color map(freakout or Pseudocolor). In here, the data is shown by only 4 colors. I ...
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1answer
391 views

How to add multiple rasters to a layer file?

I'm trying to make a .lyr file to bring into ArcMap with arcpy.mapping. I can bring a single raster into a .lyr with the script below. I'm unsure how to proceed to get multiple rasters from the same ...
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1answer
129 views

Set certain amount of pixels to 1 inside of a polygon (GRASS)

I have a rather coarse vector map with polygons and want to calculate a (sufficiently) finer raster map defined by spatial extension and resolution. Every polygon of the vector map has a value ...
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1answer
176 views

How to correlate raster map and elevation data?

I have been provided with a set of raster maps. Thanks to another helpful user here I have been able to acquire some elevation data for the same region from gis.utah.gov in asc format. Now I need to ...
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1answer
243 views

Why is transparancy of GRASS rasters missing when imported into QGIS?

I have a raster map in QGIS imported from a GRASS mapset with the QGIS GRASS plugin. The problem is that I have null() cells in the GRASS map that appear "colored" in QGIS. How can I set the ...
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1answer
81 views

How to conflate terrain data?

I have an 8 km by 8 km raster of 20 m/pixel terrain data. The georeference data has been lost. All I know is that it's within 100 km of Smithers, BC. I realize that this might involve some very heavy ...
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1answer
2k views

How to merge different classes/clusters in one single raster in arcgis 9.3?

I've created a signature file with 8 clusters and performed an unsupervised classification. Later I have grouped values (spatial) classes together to form 4 classes I needed (in symbology) but that ...
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1answer
185 views

gdal_rasterize -at function still won't capture covered pixels properly

I'm currently using the gdal_rasterize tool in bash. My code looks like this: gdal_rasterize -l $(basename $file .shp) -burn 1 -a_nodata 0 -te -180 -90 180 90 -tr 0.1 0.01 -at -ot Byte $file $OUTPUT/...
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2answers
275 views

Break between two raster layers (topographic maps)

I have the following problem [in QGIS]. In displaying two raster layers (topographic maps), a white area appears between the two. If I apply transparency to one of the layers, this white area still ...
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4answers
926 views

Determining gradient of road segment

I've a shapefile of roads data. It contains information about terrain of road segments, i.e., hilly, flat, undulating, etc. I want to determine gradient of every road segment. I know this might ...
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1answer
2k views

How do I add TIFF files to one layer/raster catalog?

We have several TIFF images (already tagged with position information) we want to load as a single layer into the map. It's the first time I dig into this raster/topology thing, but at least I managed ...
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1answer
421 views

Adding Field to Raster

Good day! I have a shapefile which contains X-specific field. I want to add this X-specific field (integer) to a raster dataset. I am using ArcGIS 10. How can I do this? Thanks.
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1answer
127 views

Can I avoid runtime raster interpolation by creating an image pyramid to match the zoom scales?

For image quality and performance reasons, it would be best to perform interpolation of my large TIFF image of the world (10GB) beforehand to all the zoom scales I need to display at so that MapGuide (...
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1answer
484 views

How to serve raster mosaic to AutoCad Map 3D from ArcGIS Server without its Image extension?

We are looking for a way to serve all the raster datasets we've collected over the years as a mosaic we have built in ArcGIS so that the AutoCAD department can simply import the mosaic and it will ...
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2answers
334 views

Configuring a WorldImage data store starting from a folder containing tif and tfw files

i have a folder of tif and tfw files and i'd like to show the raster in a map using geoserver. Even reading the geoserver tutorial for this kind of datastore (http://docs.geoserver.org/stable/en/user/...
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1answer
238 views

What are strengthes and flaws of using grid-cell analysis in GIS? [closed]

I'm going to use grid-cell analysis. What are the strengths and weaknesses?
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1answer
639 views

Preventing an Openlayers WMS layer from updating on zoom-change

I'm using openlayers to overlay a raster. When I zoom out, the overlaid layer expands to cover a larger area than was originally requested. I want the tile to be fixed to a particular boundary, and ...
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1answer
1k views

How to convert Geostatistical analyst (GA) file to Raster FAST?

I have been trying to convert a number of Geostatistical analyst files that i were created using Geostatistical wizard in ArcGIS 10. I want to save these files as Raster and use the File Am i ...
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1answer
3k views

How can I extract raster values around points?

I'm using ArcMap 10. I have a point dataset and a .flt raster. For each point I want the sum of the raster values that lie within a certain radius of each point. i.e. I want to extract values within a ...
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1answer
322 views

PostGIS Raster convolution filters

I've looked through the PostGIS raster documentation, but can't find an indication of how to apply a convolution filter to raster data. Does this capability even exist (yet?) There only appears to be ...
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1answer
581 views

OpenLayers ArcGIS Image Service Support

i have ArcGIS Image Server for publishing my raster data to my user. In traditionally way i have been tiling with gdal and it takes a long time besides this it requires more effort for getting true ...
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1answer
155 views

ESRI ISurface.GetElevation is extremely slow compared to GlobalMapper

I'm using ISurface.GetElevation on a Raster to get the elevation for a specific lat/lon. I have to do this for a huge set of datapoints. Currently i'm testing with a dataset of 10.000 items which ...
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1answer
138 views

Blank Vector Selection Dropdown in QGIS GRASS Plugin

I realise there are some issues which getting vectors into the GRASS module in QGIS, but is the behaviour i am getting expected? I have loaded the vector shapefile via GRASS, closed G and reopened ...
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1answer
308 views

How can GRASS export an .flt file?

I am using GRASS and connecting it to another application. The other application needs an FLT file of the raster map which I should export from GRASS. The other application only reads FLT files. Can ...
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1answer
149 views

Clip GAPAnalysis and save as a new file output strange looking colors

I download USGS GAP Analysis and use a polygon to clip raster from that GAP Analysis. I am wondering why there is a strange looking color when you clipped the raster. If you zoom in, you can see ...
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1answer
454 views

How to use r.patch with two maps having different colortables?

I am using r.patch to combine two raster maps in order to fill in the null values of the other. Is there a way to use r.patch but still maintaining the colortables of the separate raster maps? I do ...
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1answer
282 views

Creating color table file in PCI Geomatica

What is the simplest way to create a stand-alone color-table file in PCI Geomatica (PCT or STR)? I have some classified imagery with values ranging between 0-255 and I would like a way to ...
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0answers
16 views

How to save raster output in different directory without duplicate in set workspace? Arcpy

I am using the Weighted Overlay tool in Arcpy and I've not had this issue before with other tools. I'm wondering if it's a tool-specific problem. The output I get from the weighted overlay tool saves ...
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1answer
13 views

random sample of raster cells based on multiple classes in R

I have a raster dataset that is classified into vegetation classes. I would like to randomly sample from the dataset based on the vegetation classes, but not sure how to do it. Here is some example ...
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1answer
32 views

GDAL Raster plugin doesn't work

I am connected to Oracle, using QGIS and can see the vector data table. I am trying to use the GDAL Raster plugin to view raster data, in QGIS. When I click on the Oracle GeoRaster plugin, get a ...
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0answers
22 views

Can I use georeferenced jpeg raster as map layer in GeoJSON.io?

Can I use georeferenced .jpeg raster as map layer in GeoJSON.io? I thought that I could, but it doesn't work. I converted .tif raster visualization of LiDAR data to georeferenced jpeg. After this, I ...
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1answer
28 views

How to resize a raster SUMMING the values of pixels in QGIS?

I would like to be able to resize a raster such that the values of the resized pixels are based on the SUMS of the original raster pixels, rather than the averages. The output should be generated thus:...
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0answers
15 views

Resolution changes when exporting raster from GRASS to Arcmap

I have a raster file of rainfall (floating) in GRASS that I want to export and open in arcmap. If I look for the raster file in GRASS, it has Rows: 140 ...
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0answers
29 views

Multiband virtual raster with gdalbuildvrt: Control how bands are sorted

I am making a multiband virtual raster using gdalbuildvrt. Everything works fine, but a little detail remains annoying: I cannot control how the bands are sorted. I specified the input raster using ...
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1answer
45 views

Extracting small numpy array from a bigger raster, by moving windows. Memory issues. ArcGIS

I'm trying to extract a small raster from a bigger one, just using python and numpy (I'm not allow to use any other software). This code just reads a from a big raster, extracts an smaller window, ...
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0answers
27 views

Extract mean raster values by fishnet in ArcGIS [closed]

I have a raster of 0.25m resolution. I created a fishnet with 100*100 m in ArcGIS. I want to extract mean values of the raster from fishnet squares(100*100). I tried zonal statistics in ARC but does ...
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1answer
18 views

How to select a fixed dimension ROI in ENVI?

ENVI provides the freedom to select ROIs by drawing polygons etc. I want to clip a fixed size ROI, say 512 x 512 in size. Is there a way to do that?
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1answer
27 views

How to calculate the area in kernel density?

I have estimated and reclassify my kernel densities and I would to calculate the area of each value. How could I do it? My Projected Coordinate System is WGS84 World Mercator. My pixel size is 10000 ...
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2answers
43 views

How to define season by month and average data

I have 10 year NDVI data i.e. two values per month. I would like to average values within a season e.g Season A (January, February and March) per year and plot a graph. y axis=average ndvi value, x ...