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

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ArcGIS Javascript Legend widget does not show full color ramp

Has anyone used the legend widget with raster map services? I have created a GP service that returns raster maps, but the legend is incomplete. The ArcGIS layer properties are shown here, and below ...
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60 views

raster2pgsql stops at line 53 at RETURN

I am importing some very large rasters (in the tif format) into Postgres SQL (9.3) using raster2pgsql on the command line. Most of the rasters imported fine, some had to be converted to the img format ...
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Automatically applying a local ortho projection using the center of the raster layer extent

I would like to take a raster image read the layer extents, extract the center point and then apply a custom local ortho projection with the origin set to the extracted center point. Can anyone ...
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32 views

QGIS raster: Which band is which?

I have an image from a Canon SD110 NIR camera, which I can import in RAW (CR2) into QGIS. However, I am finding it difficult to know which band represents which 'colour' output. According to the ...
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38 views

Subtracting rasters from each other in batch using ArcGIS for Desktop?

I am trying to calculate the maximum change for each cell in a large amount of rasters. These rasters are number X002,X003 till X150 and I am trying to calculate the change between 2 consecutive ...
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37 views

Select query St_asBinary(rast) returns out of memory for query result

I have very large rasters (7000x3500 cells) in postgis (2.1.3) postgres (9.3.4) that I want to pull down via psycogp2 and create numpy arrays and ultimately a geotiff. Initially I found I had to use ...
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15 views

QGIS change zones in a raster to grayscale by polygon overlay

I've got a raster ortophoto and a polygon layer: I need to alter the raster layer as follows: Everything that is inside the polygon (overlaying) should stay as it is right now (in color). The ...
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17 views

How to center the QGIS map on the maximum value of a raster?

I have a very large QGis raster layer showing the differences between two nearly identical rasters. Because of this, it is very difficult to find where in this layer the few pixels that are different ...
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40 views

Layer failed to load?

I have this piece of codes running via pyqgis and trying to get raster layer from "elevp.csv". However, when executing this scripts it error kept returning "Layer failed to load". Anyone know how to ...
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30 views

How to create a raster “grading” several different layers (polygons)

So I have a bunch of different shapefiles loaded into qgis: i.e.: - shape of poor soil quality - shape of cheap land areas - shape of poor weather areas now I would like to create a map which "...
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98 views

Kernel Density Estimation Crimestat

I calculated a series of Kernel Density Estimations in CrimeStat (because more parameters can be set than in the built-in tool in ArcGIS) and then imported the results into ArcMap. I wanted to combine ...
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60 views

Raster distance for statistical analysis

I am trying to some kind of hedonic analysis. I need to calculate driving forces for new urban areas. In order to do this, i have a raster with new urban area's and one with existing urban areas (...
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66 views

R raster stack 4 dimensions

I am trying to create a raster stack / brick from a list of ncdf files with the dimensions 160x160x24x1). r = stack(files) This gives me a raster stack but without the 4th dimensions which is ...
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63 views

Why does gdalwarp's cubicspline method expand into nodata areas?

The image below shows part of a peninsula on the Australian island of Tasmania. The black pixels are 9" climate data with GDA94 (EPSG:4283) SRS, projected by QGIS on the fly to Australian Albers (EPSG:...
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102 views

How add two coverages with different bounding-box and different resolution using geotools

I'm developing a Java application with some spatial analysis operations. One of the operations is to add two coverages. But how can I add two coverages with different bounding-box and different ...
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292 views

How to Convert from Point to Continuous Raster in ArcGIS 10.1?

I have a vector point dataset that I would like to convert to raster. The point-to-raster conversion tool creates a raster grid with spaces between each grid cell. I want to create a 'continuous' ...
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79 views

gdallocationinfo used in javascript with node-gdal?

I've been scratching my head for a white trying to figure it out if it's possible to get pixel information from my rasters using gdallocationinfo in javascript. I found node-gdal, but after reading ...
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40 views

Rasters with duplicated data

I am working with a number of raster files that suddenly appear to have duplicated records. For example, I have a raster that classifies my study area into aquatic (value = 1) and terrestrial (value = ...
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57 views

Lat/Long grid array 360x720 for ArcMap raster layer?

I have two files (global temperature and precipitation), both in a 360x720 grid array (latxlong) in a csv file. I'm trying to add this to ArcMap 10.1 so I can use it in raster format. I've added the ...
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36 views

How to generate map tiles including world files in QGIS?

Is there any way to export bitmap tiles including world files from a QGIS project? I've tried QTiles but it seems not to support world files.
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27 views

Zonal statistics shifted

I am working with QGIS (newbie). I have a raster map with 0.5degrees resolution. I created a 0.5degrees width grid layer and I compute zonal statistics from the raster. My problem is that it seems to ...
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56 views

Is QGIS aspect analysis description mistaken?

I've been checking the Aspect analysis tool and several sources indicate that aspect is measured from 0 to 360, starting North and going counter-clockwise. Nevertheless, I've been testing it on ...
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137 views

Custom data source for GeoServer raster image

I'm working on a project where a custom binary data file contains latitude, longitude, and temperature data. I'm interested in creating a DataStoreFactory plugin to enable GeoServer to load this ...
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68 views

export several rasters from grass

I'd like to export 127 raster files from grass to .tif in one operation. I already stumbled over this post How to batch export using r.out.gdal command in GRASS but it doesn't work (I don't even know ...
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102 views

Subset moving window when using focal on raster in R

I have a classified Landsat image, and I'd like to pass a filter over it converting certain cells to 0. For some categories, I'd like to set cells to 0 unless an entire 7x7 window contains only that ...
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53 views

Raster Area within a Polygon

using ArcGIS, I have a layer of overlapping polygons and a raster grid underneath. The raster is not a continuous grid - the cells are spread out. I simply need to calculate the total area of the ...
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115 views

How to create contours from an IDW raster

I'm new to QGIS and am trying to create vector contours from this IDW raster. I followed Ujaval Gandhi's "Interpolating Point Data" tutorial step by step but am not getting the same results for step ...
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184 views

Performing Theil-Sen regression on raster data by R software

I have seven NDVI raster layers (in ERDAS img format) of an area. Each NDVI layer is the peak growing time of that year. I want to do trend analysis of NDVI values change over the years pixel by pixel....
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61 views

Assigning Raster Cell data to Point data

I have 23 sets of raster data for different types of habitat (which I have performed Block Statistics on in Arc10.2, in order to create a 1km grid). I also have 5 different Sets of point data showing ...
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72 views

How to align hundreds of rasters quickly

I'm hoping to accurately align hundreds of aerial images that are slightly off-kilter. The images cover the same area on different dates (several acres). They contain identifiable features around ...
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349 views

How to obtain an euclidean distance raster from a vector file in QGIS?

I'm trying to obtain a raster of Euclidean Distances from a vector layer I have of a river in Spain. I did it very easily with ArcMap using Euclidean Distance, but I don't know how to do it in QGIS. ...
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70 views

Where can I download a raster dataset with the latitude and longitude of each pixel in geographic projection?

I want to do raster calculations in QGIS based on the latitude and longitude of each pixel. The calculations will compute the area of the pixel, but also do other calculations for various projections ...
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241 views

Invalid drop item: Calculate statistics

I have a number of rasters that I need to calculate histograms for. These are continuous rasters from 0 to 294.208 - many decimal places. I need to be able to classify the histogram down to at least ...
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48 views

Replacing white or black by alpha channel in raster in QGIS 2.8

I'd like to replace black or white in black and white raster in QGIS 2.8. I perceived that in some other raster where "nan" value automatically occurred and only white or black is being displayed.
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62 views

calculate Z~F from polygon and raster

I have a polygon shapefile and raster layer. How I can calculate the elevation and area (Z~F) relationship for each polygon by using QGIS or ArcMap?
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136 views

PostGIS: intersection of a polygon with 2 rasters

I'm trying to get the intersection of a Polygon with 2 raster layers in PostGIS. The rasters have the same size and pixel size and I'd like to retrieve for the polygon a list of something like that: ...
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37 views

Error in merging two raster files (precipitation) in QGIS

The newly computed geotiff shows the extent of both raster layers, but only the data of one. If I use identify features tool it gives me only the values of the visible part not of the other part. I ...
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23 views

Raster images overlaying each other but shouldn't

When I open a new map document and drag different raster images into the map the images stack on one another rather than form the complete image of a country. When I try zooming in, the multiple ...
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94 views

ArcPy reading a raster in a moving window?

I typically read large raster data using gdal and setting up a moving window of 256*256 pixels (for example). I recently had to do some processing using arcpy, so I did the same thing, using arcpy....
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97 views

Substract 2 rasters with Raster Calculator in ArcObjects (VB.NET)

I'm having a hard time substracting 2 raster with ArcObjects sdk 10.1. I keep getting a nullreference exception at the gp.execute() method, but I can't figure out where the problem is, I recall ...
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175 views

How to create ROI in Semi-Automatic Classification plugin QGIS

while trying to classify landsat images, I get the following problem: I click on the pixel I want to define a ROI, but the ROI polygon that the plugin creates appears in a different part of the image ...
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43 views

How does `ST_Union` treat NULL values in a raster?

My question is about how ST_Union of rasters containing NULL values are handled. For example suppose I have two rasters that intersect but the values of the intersection are NULL in one of the rasters....
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118 views

Zonal Statistics for multiple rasters

I'm trying to create a timeseries of raster data (one layer per year) by polygon (Administrative regions). Is there any way in QGIS to perform Zonal Statistics for multiple years (without having to ...
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50 views

'combine' more than 20 raster bands

I have overlapping polygon data that I would like to 'combine' in ArcGIS and I'm running up against the 20 band maximum for rasters. I'm interested in solutions using this basic method with Arc or ...
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37 views

Merging DEM files using PostGIS

I have several DEM files and I want to merge them to create a mosaic. I found the St_Union(raster) or St_MemUnion(raster) functions but I don't know how to use them. Are there any other solutions?
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146 views

When subtracting two raster with different cell sizes using raster math, what value is used for smaller cells?

After reading the answer to a similar question (What will happen if we subtract two raster with different cell size using Raster Calculator?), I am still left with a question. When the raster with ...
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36 views

Transforming climate text data to raster in ArcGIS Desktop?

I have climate data in text files with no header in the format below from Udel's climate program. Each row has a lat, lon, and a temperature for each month (14 columns total) from 1900-2010. I need ...
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72 views

Remove Frame Border from USGS scanned images in ArcGIS

I have a couple of USGS scanned maps like I want to remove the frame border from these images so that I can use them in ArcGIS. Is there algorithm or python script that I can run to remove the ...
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23 views

Second order rectification display problems

I'm using GRASS 7.0 to geo-rectify oblique images taken from a fixed altitude and using RTK-GPS data as a GCP (as a vector file) for the process. The survey area is very small and flat, so I'm not ...
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30 views

How to best import a US Map Schematic?

I would like to use the following wiki US Map schematic as a background to my map work. (http://en.wikipedia.org/wiki/File:Blank_US_Map.svg) It is a .svg file, and GeoReferencer is unable to import it....