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

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355 views

Querying PostGIS Raster with MultiPoint

For one of my projects using PostGIS 2 I have a table with GPS tracks (igc_files). It holds records including a MULTIPOINT() column that has about 1,000 points for each record and a column that has an ...
5
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2answers
333 views

In ArcGIS 9.3, how do I eliminate the slivers of missing data between polygons?

I am editing a single-band .tiff file in ArcGIS 9.3. I started with an image that I had to georeference, but unfortunately, the image had these little slivers of missing data between the data cells. ...
3
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2answers
2k views

Polygon to Raster Tool Problem

I am trying to create a raster data set from county level polygon data for the US. I have successfully created one raster from a dataset, but when attempting another, it does not work. I am ...
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1answer
1k views

In ArcGIS 9.3, how do I split a 3-band raster (.tiff) file and summarize the band values?

Using ArcGIS 9.3, I would like to make a new, single-band raster file that includes only one value: a summary of the three existing bands. The composite band is currently a composite .tiff file. ...
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1answer
180 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
61 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 ...
2
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1answer
181 views

how to create an outline polygon (footprint) from raster data with postgis?

how can I create a polygon, containing the actual outlines (aka footprint) of a raster file with postgis? I just need the outlines of the data containing parts of the raster. ST_PixelAsPolygon ...
8
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1answer
900 views

How to make a new raster using con() script in Python?

I'm new to Python and have been trying to code a raster calculator style script. Basically, I want to convert a raster that has values 0 to -10,000 into a raster that is populated by 1s between ...
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1answer
164 views

Clipping Rasters with a mask layer error

I've got a NDVI layer that I'm trying to clip with a vector file but when I try and use GDAL Tools clipper I get an error. That shows up like this: What am I doing wrong? This is before I even pick ...
2
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1answer
548 views

Orux Maps raster display

Does anyone know what format of raster images works with Orux Maps? I tried to export maps acc to Orux Maps specs from ArcGIS 10.1 in every possible format (Geotiff, GRID, jpeg2000...), loaded with a ...
2
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4answers
909 views

Attempting to bring 2,300 .sid files into one raster

I've tried all of the raster tools within ArcToolbox with no luck having such a large number of files. There are about 7GBs worth of MrSID files totaling about 2,300. Most tools fail or process too ...
4
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1answer
428 views

How to convert a JPEG to GeoTiff using FME?

I want to convert JPEG to Geotiff in FME. I use the following workspace JPEG reader -> RasterExtractor -> CoordinateSystemSetter -> RasterGeoreferencer (parameter : extents) -> Reprojector -> ...
5
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1answer
582 views

Can QGIS handle .adf attribute data?

I have been using QGIS for about 4 months now and its been great to learn a new package. I have been trying to open a source raster (*.adf) files in QGIS. I can display the raster set itself, ...
8
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1answer
2k views

How to reproject a raster file in QGIS with datum transformation?

I want to reproject a tiff raster file from projection A (ETRS89/UTM Zone 32) to projection B (DHDN/Gauss-Kruger zone 2). The two projections have a different datum so I have to use a datum ...
2
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2answers
345 views

How to get easting & northing of cell in raster using ArcPy?

It might be very simple task. But I would appreciate if someone can comment on How I can get easting and northing of a single cell raster using arcpy as this value is used for in further steps. ...
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2answers
262 views

How should I get a Raster out of ArcMap and into Google Earth (.kmz) with transparency

RasterLayerExportClass will only create a .png with a single value transparency, however there is a bug in Google earth which prevents this from working. The other export options don't support ...
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1answer
497 views

How to reproject a raster in QGIS?

I am a history teacher and I like to make my own maps (I can never find exactly what I want). I am using QGIS 1.8 and Natural Earth data. I want to reproject their cross-blended hypso rasters into ...
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2answers
168 views

how to aggregate raster values for each grid in a fishnet-like map

here is my problem: I have a raster layer containing the elevation info. and another gridded layer (shapefile type). What I want to do is to calculate the mean elevation within each grid to have a ...
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2answers
642 views

Adding a new Coveragestore in a certain Workspace by REST

So, simple thing as it seems but I can't seem to make it work! I'm trying to add a raster data file (GeoTIFF) to geoserver via REST API, using curl on linux. REST API is working, since I created a new ...
5
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3answers
583 views

Is it possible, in QGIS, to create buffers with a set radius, but with individual values taken from the attribute table?

I am looking to create an output that consists of an 11KM buffer around a number of discrete points, where the buffer has a value defined by a column in the data sets attribute table. Is this ...
3
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1answer
335 views

How to reproject a raster to Winkel Tripel projection?

I'm trying to project a raster map (in ASCII grid format) from longlat to the Winkel Tripel projection. But I'm running into errors, for instance gdalwarp won't accept the proj-string. $ gdalwarp ...
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0answers
164 views

Overlay Shapefile onto Geotiff

I have a Geotiff map and I want to overlay a Shapefile onto it. Ideally I want to specify a 'nice' style for the polygons e.g. have them opaque (for now all polygons should be the same). I want to ...
3
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1answer
560 views

raster2pgsql: Strange error when creating a table

Hi GIS Stackexchange people, When I try to load a asc file into my psql setup, I get a strange error message. I have created the sql input file via raster2pgsql -s 4236 -I -C -M gis_data.asc -F ...
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747 views

How to serve OpenStreetMap Tiles locally using ArcGIS Server 10?

We want to serve OpenStreetMap Tiles locally using ArcGis Server 10 to use as base maps in our ESRI Silverlight and Flex GIS clients. We've downloaded our regions OSM file and created PNGs using ...
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182 views

Can we create views over a raster table in Postgis2.0?

Is it possible to create PostgreSQL views over a table that contains raster data? I have succeeded in creating the view but the entry in raster_columns is not correct (all the raster info is ...
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1answer
466 views

Qgis problem clipping a raster .asc file, the output is unreadable

I am currently using QGIS (1.8.0) to prepare files for use in MaxEnt to predict species distribution in a new territory in Argentina. I need to a) cut the raster files (bioclim, and others) to a ...
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1answer
744 views

How to change 2 rasters to have the same dimension?

I am new in Quantum Gis 1.8 and have the following problem. I have extracted two raster files(land_cover.asc and soil.asc) using a polygon of my study area (area.shp) Apparently the raster dimensions ...
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1answer
2k views

Exporting map to jpg (multiple times with python)?

I set symbology and exported each raster in my mxd (one by one) to jpg file. My script is ok and it works (it is shown at the bottom). The question is: how can I customly set my legend? Now I have ...
3
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2answers
925 views

Why is Raster Layer not visible?

I have a raster dataset that is not visible in Data View, but it is listed in the Table of Contents. I have tried viewing it in ArcCatalog but it is not visible there either. Is there something I ...
3
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1answer
84 views

How to display the label with “Identify Features” in QGis?

I have been struggling for one hour with this simple problem : I have a raster layer. I would like to display the label and not only the band value when I use the "Identify Features" button. Is it ...
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302 views

Using ArcGIS to filter cells where 7 or 8 of the neighbors are different

I have land cover data that I would like to clean using some generalization tools. Majority filter does almost exactly what I want, but is missing one key option. Majority filter allows you to change ...
5
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1answer
808 views

How to keep spatial reference using arcpy.RasterToNumPyArray?

I am using ArcGIS 10.1, and want to create a new raster based on two preexisting rasters. The RasterToNumPyArray has a good example which I want to adapt. import arcpy import numpy myArray = ...
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3answers
3k views

Writing numpy array to raster file

I'm new to GIS, and I'm lost with something I feel ought to be relatively simple. I have some code that converts infrared images of Mars into thermal inertia maps, which are then stored as 2D numpy ...
4
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1answer
660 views

Getting a constant background color for transparency

I am creating a series of tif files at 1:10k scale over a vast area (760 tiles) using arcpy.mapping.ExportToTIFF and then stitch them together to create a single ecw. The output looks ok but when I ...
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2answers
1k views

raster2pgsql part of PostGIS?

Hi GIS Stackoverflow people, I wanted to use the PostGIS functionality raster2pgsql, but I had to discover that the Python function was not installed with my PostGIS installation. Do you know if ...
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1answer
555 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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2answers
1k views

How to classify/style rasters correctly?

I am using a GeoTiff raster data and trying to classify it. I was wondering what are the techniques that I can use in QGIS to do this? The raster I have looks like but I tried the reclassify tool ...
3
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2answers
3k views

How do you use GIS to detect percentage of Land Use Change

I am a student in GIS I have a dissertation about land use change. I have questions about using ArcMap 10 for this aim, how can using GIS to detect the percentage of land use change. For example we ...
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1answer
97 views

how do I select more than one features from raster attribute table

for ex: "lc_2001" = 21, 22, 23, 24 AND "lc_2006" = 11, 31, 41, 51
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3answers
1k views

How to sum raster image values with vector overlay

I'm new to this and haven't been able to figure out how to do this on my own. Here's what I want to do ... I have two files: a raster image of land use data and a vector-based shapefile of my ...
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389 views

How to reproject a raster in QGIS? [closed]

I wanted to reproject raster file from UTM to decimal degree in QGIS version 1.7.1 or 1.8.0.. I could reproject one raster file before in QGIS Version 1.8.0. I have tried again, but now we cannot ...
5
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1answer
690 views

What is the best practice for reading data from a raster band with Java and GDAL?

After using GDAL with Python for a year or so now, I'm getting back into Java and trying to figure out how to use GDAL with it. I am wondering if anyone has had experience with reading data from a ...
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0answers
114 views

Raster display for topographic map

I'm trying to see how good a custom topographic map could be using only free data For the moment I'm just playing with the data so of course the colours are not pretty. I did some classification and ...
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1answer
188 views

Setting projection to a geotiff file when it's shown as Unknown

I have a geotiff file that has no CRS in the metadata but I know that the CRS of the raster is WGS 84 UTM 22 N. How can I modify the geotiff file to have the CRS WGS 84 UTM 22 N in the metadata. ...
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71 views

Create 6 band IMG file with GDAL out of two JPG files, one with WorldFile coordinates

I have two JPG files 1 ortomap: http://imageshack.us/photo/my-images/703/ortofoto1.jpg/ with WorldFile: 0.683772574816354 0.000000000000000 0.000000000000000 -0.683739485024190 ...
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1answer
267 views

Georeference Raster File with WorldFile into an aerial photo using GDAL [duplicate]

Possible Duplicate: How can I transform a georeferenced JPG to a georeferenced TIF? UPDATE:Corrected link I must note that I am new to GIS so pleas be understanding. PROBLEM: I have a ...
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1answer
480 views

How to view a 155 MB raster stored in PostGIS?

I am using the following command to load a raster into a postgres database: raster2pgsql -I -C -e -Y -F -s 3086 -I -C -M myraster.tif myraster -F -t 30x30 | psql -U postgres -d database -h localhost ...
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1answer
150 views

Probability distribution from list of rasters

I have 100s (exactly 224) of wind distribution rasters. I want to create a probability distribution raster of wind speed using all these rasters, so we can predict the possible wind speed in any ...
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3answers
808 views

How to display row and column indexes for an image in ArcGIS?

I have been struggling with how to find the row number and column number for particular points in any raster map. My raster details: columns and rows: 720 360 cell size (0.5, 0.5) How can I ...
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2answers
279 views

Is there a way to load a kml raster super-overlay in QGIS?

I have created a set of tiled rasters as a super-overlay in Google Earth, and it performs remarkably well. Is there some way to load a super-overlay as a layer in QGIS? I am wondering if this could be ...