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

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How to surround a clipped raster with transparency? (gdalwarp)

I am trying to perform the following task, but it does not seem to work: I have got a raster file (raster.tif) containing an aerial photo, which I want to clip using a Shape file (clip.shp) that ...
7
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2answers
414 views

How to remove long linear strips from polygons?

I have a polygon layer representing impervious land cover. This was taken from a land cover raster dataset. The impervious data represents all impervious surface that is not buildings or roads. I ...
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3answers
1k views

Find a proper path between two nodes in a grid

This question is about finding a proper path (route) between two nodes (P,Q) in a grid (i.e., graph, network, ...). In our concept, we define a path proper (nice) if it is the most similar* to the ...
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1answer
82 views

What units are used in GRASS Rasterize?

What units are used in GDAL Proximity or GRASS Rasterize? - 'new size' parameter
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324 views

Error when trying to import a raster file into a geodatabase

I am using ArcGIS 9.3.1. For some time I have had no problem importing a raster file into my geodatabase. That's recently changed and I have absolutely no idea why. Every time I try to import a raster ...
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3answers
24k views

Extract Raster Value into Polygon Attribute

I have Raster Data for a State which has Elevation Data in its pixels. I also have Vector layer which has the 300 divisions of State. what I need is, I want to get the average elevation value of ...
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2answers
493 views

How to produce a mean raster file based on other raster files? [duplicate]

Possible Duplicate: Tools to flatten the jp2 to a single band (average the bands)? I have a number of raster files from a same area, that coordinates of corresponding pixels perfectly match ...
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1answer
406 views

Problem editing raster and saving with projection and transformation intact

I am trying to make a custom tool to Arcmap using Python. It is supposed to read in a raster DEM, a point shape file and a distance, and output another raster. The output raster should be ...
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3answers
2k views

calculate area of vegetations in a raster file

How do I calculate area of several vegetation types in a raster (.img file type) image. They are color coded. Am using QGIS (1.8.0) and ERDAS 9.2.
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1answer
392 views

Stitching thousand of 32 bit Tiff without geographic information

I'm working on a project which goes beyond my knowledges, I need your help. I'm working with FLIR movies (thermal imagery recorded from plane), and I have to find a way to make a Tiff containing the ...
8
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3answers
3k views

Using polygons to apply unique value to all raster cells within those polygons?

In ArcGIS 9.3, I have a raster file that I would like to "mask" with polygons, giving a single value to all the raster cells that overlap the polygons. How can I do this? Here's a screen shot, ...
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1answer
513 views

How can I create a pollutant dispersion raster in QGIS?

As my previous questions have indicated, I am working on an air quality problem where I have a dataset of industrial emissions that consists of a location (long, lat), and an annual volume of ...
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2answers
1k views

Zonal Statistics as table creates output but some are Null

I have temperature as a raster file and different ecoregions of a province as polygons. What I want to do is calculate the mean temperature per ecoregion. I succeeded in doing this by Zonal ...
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2answers
2k views

QGIS - extract raster values greater than 0

How can I extract values > 0 from an overall raster? I have a water level grid and a DTM from which I've derived flood depths (using the raster calculator) but obviously the final result contains ...
2
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1answer
399 views

how to load a raster into the Map Canvas using QGIS Action

Is it possible to write an Action in QGIS that will load a raster into the current map canvas based on a url/path of the raster as specificed in the attribute table of a shape file? The shape-file is ...
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1answer
501 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 ...
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2answers
557 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. ...
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3answers
4k 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
3k 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
222 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
71 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
264 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 ...
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1answer
2k 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
227 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 ...
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1answer
993 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 ...
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4answers
1k 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 ...
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1answer
823 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 -> ...
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1answer
4k 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 ...
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2answers
444 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
407 views

Getting Raster exported from ArcMap into Google Earth (.kmz) with transparency preserved?

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
1k 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
244 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
1k 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 ...
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3answers
845 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 ...
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1answer
500 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
197 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 ...
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1answer
903 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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0answers
1k 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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1answer
190 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 ...
3
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1answer
693 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
1k 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
3k 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 ...
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2answers
2k 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 ...
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1answer
104 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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2answers
502 views

Using ArcGIS to filter cells where 7 or 8 of 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 ...
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2answers
1k 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
6k 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 ...
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1answer
1k 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
1k 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 ...