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

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227 views

Can't view PostGIS rasters after changing schemas

I have loaded a few rasters into the Public schema of a PostGIS 2.0 database. Using the db manager in QGIS 1.8.0 I can add the rasters to the map canvas. After moving the rasters to another schema in ...
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1answer
102 views

Area surface doesn't match

I have three municipalities with a total surface of 178 sq km. I want to analyze land cover of those municipalities using both LANDSAT images with a pixel size of 30 x 30 meters and SPOT with a pixel ...
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2answers
3k views

Can ArcGIS Desktop stack layers?

I have 7 bands of Landsat and I would like to combine all layers into one layer. Can ArcMap 10 do this like Erdas software can?
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2answers
354 views

Creating planes, eg roof surfaces, from LiDAR/DSM data

I am capturing the area of roof tops of buildings from a DSM (derived from LiDAR data) which has not been much of a problem. I can then also derive angle, hillshade and aspect but it is only ...
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1answer
740 views

How to convert multiple rasters to new raster (mosaic)?

I want to use Mosaic To New Raster in ModelBuilder. I want it to give me multiple outputs because I have multiple folders with a different number of images in each. Below is the model that I have ...
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1answer
340 views

How to create a raster mosaic from many asc files

I am trying to create a raster mosaic (in ArcGIS 10.1) as I am working with many asc files - I am trying to put all the different tiles together in order to run a view shed analysis. I have been told ...
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0answers
202 views

PostGIS raster functions aspect and slope slow

I am trying to compute the raster and slope values from a DGM table (8184 x 5159) imported from tif file tiled in 500x500 tiles. In my query in which I merge the DGM table with a vector (point type) ...
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1answer
338 views

ArcGIS TabulateArea() :: Recommend Ratio of Zone Area to Value Raster Cell Size?

Any recommended ratio of zone area / raster cell size when running small input zones with ArcGIS Tabulate Area Tools? Esri mentions: If the zone input is a feature dataset with relatively small ...
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58 views

simple raster format to use in Web applications?

I'm building a Web application in which users create and edit very coarse raster data. They're assigning values to cells in a georeferenced grid. Right now I'm storing the values in a multidimensional ...
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1answer
49 views

How to export Std Dev from Raster Dataset of DEM to classify current extent and execute Contour Tool with Python?

I want to create Countour Lines for a DEM which are based on a "STD dev" classificaion. My problem is that the "Std dev" is exported in an unknown type instead of a String. So the classifacation for ...
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265 views

Assign spatial reference for 1000 different ECW raster datasets using 1000 different *.prj files through python programming or .net

I am having 2000 ECW raster datasets without spatial reference and also I have 2000 *.prj files in another folder. I know only the way as right click on raster datasets-->properties-->Spatial ...
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2answers
317 views

What causes ERROR 000732 from MosaicToNewRaster?

I'm trying to run the MosaicToNewRaster tool as part of a python script. This is my code: input_rasters = arcpy.GetParameterAsText(5), arcpy.GetParameterAsText(6), arcpy.GetParameterAsText(7), ...
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1answer
117 views

How can I establish patterns, hotspots and clusters?

AS a crime analyst you need to establish a few maps that would help police to do targeted patrols, I've given data of suburbs, roads, incidents, boundaries. How can I establish patterns, hotspots and ...
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1answer
237 views

Help loading Raster to PostGIS 2 .0

Similar questions have been asked, but since my reputation is not enough I am unable to comment on answers. (The following is from an answer by nickves for this question Loading raster data to ...
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1answer
520 views

How to batch merge rasters using FOSSGIS tools?

I'm working with QGIS 1.8 (gdal 1.9.2) and GRASS 6.4.3...but on Windows 7. I "just" want to merge my raster. I've got a folder with 50 GTiff raster from Lidar data. The aim is to merge raster ...
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0answers
156 views

Floating Point UniqueValueRenderer

I am trying to build a unique value renderer using ArcObjects .NET. All the samples that I have seen use the attribute table to build the UniqueValueRenderer. However, my raster does not have an ...
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6answers
957 views

Interpolation of multibeam bathymetry

I'm trying to make a 3D map with multi-beam bathymetry (65536 features, xyz), but it seems that the interpolation methods are too rigid. I need to smooth the data so it looks more natural and ...
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2answers
627 views

Can I prevent QGIS raster clipper from changing output cell/pixel size?

I have performed a DEM extraction using the clipper tool in QGIS 1.9.0 Master, using a mask layer, the original resolution of the DEM is 20x20 but in the resultant DEM the new resolution is ...
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1answer
315 views

Working with Interrupted Goode Homolosine data

I'm trying to use Global Land Cover Characterization data from the USGS: http://edc2.usgs.gov/glcc/fao/data_specifications.php It is in the Interrupted Goode Homolosine projection. As I am working ...
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1answer
442 views

Qgis crash when I attempt to open ECW raster format.

I added Ubuntugis unstable repo and installed Qgis, libgdal-ecw-src, libecwj2-3.3 but still do not work. When I attempt to open an ecw file with Qgis it crash and tells me that there are problems ...
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1answer
99 views

Adding raster image to Raster field with Python?

I have a feature class with with field that is of Raster data type. I want to add an image to each record in the feature class. Is it possible to use Python to add the image to the Raster field for ...
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0answers
596 views

How to Smooth Polygons after converting DEM using Raster to Polygon?

I have a DEM SRTM that I classify using Spatial Analyst Tools > Reclass > Reclassify. The result is box shaped so I go to Layer Properties > Display and choose cubic convolution. The result is ...
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282 views

How to import binary arcgis maps into R

I have imported arcgis rasters into R. The rasters are binary maps and the legend in arcgis shows this to be binary as the colors are only 0 and 1. Now, when I import the raster into R it is no ...
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1answer
574 views

How do I convert from points to raster making the point the lower left corner of the cell?

How do I convert from points to raster making the point the lower left corner of the cell? I'm using ArcGIS 10.1. The default for the "Convert Point to Raster" tool is to make the point the centroid ...
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1answer
367 views

ESRI Raster Remap with Decimals

I have a requirement where the user would like to see the output value in a raster as a decimal. The user will input a series of ranges with a cost associated to them. For instance 0-5, 1.20 ...
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54 views

Align OpenLayer raster with OS Mapping Vector

I have an OS Vector map of a town in Ireland. When I load the Google Satellite Raster from the Open Layers plugin, the results are slightly off, by about 2m, probably due to ariel persepective. I'm ...
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65 views

How to deal with the situation when two rasters stacked together in arcgis?

I am doing a project about petroleum geology. There are several formations needed to add attributes (e.g. name, thickness and age). I have the raster data of thickness, so I created a raster catalog ...
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1answer
2k views

combine raster and polygon values in R

My question is similar to this one Get Raster Values from a Polygon Overlay in Opensource GIS Solutions but I think I need another step. I have a polygon layer of ecoregions which I brought into R ...
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2answers
652 views

Set Blend Width on Mosaic Dataset, ArcGIS 10

I've made a mosaic dataset of some thermal imagery. There are three overlapping images, seen here: As you can see, there is a discontinuity (jagged edge) between the two images on the right, and a ...
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1answer
2k views

Replace NA's with 0 for raster data using R

I am new in R. How can I replace NA's with 0 for my raster data which have spatial information?
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2answers
735 views

Histogram Matching using Python to improve mosaicking process of multiple overlapping rasters?

I am trying to do histogram matching using Python to improve the mosaicking process of multiple overlapping rasters. I am basing my code on that found at: ...
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1answer
159 views

show dwg,as background not as vector

I have some dwg files that i need to show as background on my map, but the DWG is not need to be vector layers, i need only to show them with out the need of using. if i am trying to convert it to ...
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169 views

Can extracting raster values work in polygons' CRS without raster resampling?

I am trying to extract raster values using polygon layer with different CRS. Raster is in WGS84 (EPSG:4326) and the polygons in UTM (EPSG:23031). 1. If I want to work in the projection of the ...
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1answer
690 views

Define transparent color in singleband pseudocolor raster layer style

Can I somehow define "transparent" color for values higher than 32000 in raster layer? See the style dialog:
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1answer
150 views

GeoTIFF without projection?

I have encountered a GeoTIFF raster files with EPSG:4326 (WGS84), i.e. no projection defined! Is this normal? I would expect raster to be in Projected Coordinate System. Raster is a grid of pixels so ...
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2answers
394 views

Exporting raster data from QGIS in chosen projection

EDIT: it is seeming like some of the time my last method will lead to a correct projection, some of the time it will not. Unsure what's happening there but at least trial and error will get me ...
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2answers
1k views

Clip_management to raster extent outputs larger raster than raster extent

Using Python and ArcMap 10.0 SP5, I'm trying to reproject and clip a large input raster to exactly the same grid as a smaller target raster (same extent, pixel sizes and projection). The problem is ...
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1answer
354 views

Sensitivity analysis for coarse scale GIS epidemiological model?

I am working on an epidemiological model with disease incidence rate as dependent variable and environmental factors as independent variable. Disease data is available at county scale whereas ...
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123 views

Copy Raster Tool and 1bit to 8bit

I have a bunch of 1 bit rasters (700+) of scanned maps that I need to convert to 8-bit rasters. It's the only way Geosoft will recognize the spatial coordinates of the TIF as they don't deal in 1bit ...
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1answer
998 views

Geoserver with ECW image file

I am trying to show ECW ortophoto as base layer in openlayers. So i found this thread on GIS SE: Geoserver 2.1.1 with ECW (v3.3) support 1. Download Geoserver 2.1.1 from ...
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3answers
417 views

How to use the GeoServer REST api to get a PNG representation of a layer?

Does anybody know if I can retrieve by REST service in GeoServer an raster representation of layer? Just like in for ex. ArcGIS REST Api: When I send: ...
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20 views

Scale factor (constant not linear stretch) GDAL [duplicate]

I need to re-scale a geotiff with gdal. I'm aware that gdal_translate has a -scale function, but i need to actually apply a constant (eg value(x,y) * 100) instead of scale the pixels to within a ...
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0answers
1k 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: ...
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1answer
126 views

How to make raster cells with a certain value stand out in QGIS?

I would like to make my raster cells glow in QGIS. If I have a dataset where only a few pixels has a value, they can be pretty difficult to spot (unless I know where to look). Stretching helps a bit, ...
2
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1answer
240 views

Right raster zonal statistics for NDVI at county scale?

I am currently doing a modeling project at county scale in which I have disease rate as dependent variable and environment variables (such as temperature, NDVI and evapo-transpiration) as the ...
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2answers
159 views

Batch Fuzzifying with ModelBuilder

I am trying to run the Fuzzy Membership on simultaneous rasters in ModelBuilder and I am running into the problem (or bug) where it allows me to change the "Membership Type" but ends up defaulting to ...
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2answers
395 views

SPOT NDVI time series

I have 423 spot.vgt ndvi from first April 1998 till 31 Dec 2009. I want to know how to stack these NDVI to have one image for time series analysis? Or better to ask how is it possible to analyze a ...
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2answers
2k views

How can I use GDAL to batch define a projection?

I have a fodler with 1500 ECW rasters, no spatial reference information defined. Can I use GDAL to batch define a projection for all 1500 in the folder?
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1answer
570 views

Having issues removing white background from Raster images

I've got an issue with 4 raster layers that I have converted from kml files into layer files. It would only allow me to convert them if I used ground overlay and now the 4 raster images are ...
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0answers
86 views

QGIS: “No data” raster value for missing rows conflicts with data?

I’m having a problem with specifying “no data” in a raster dataset in QGIS 1.8.0-Lisboa. QGIS does fine in interpreting pixels I don’t have rows for as “no data” if I set Layer Properties -> ...