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

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Raster layer not visible after changing color rendering in Qgis

I created a new raster and it appears in the layer list, its visible on the screen and the values seems to be correct. When I change the "band rendering" from "Singleband gray" to Singleband ...
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38 views

QGIS Time manager

I am trying to use the Time Manager plugin in QGIS to create a time series of some raster data. I get the following error message: AttributeError: 'QgsRasterLayer' object has no attribute ...
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31 views

Adding value in raster file from attribute table in QGIS?

I have a raster (in tif format) with one band (an ID number). I also have an attribute table with several fields(columns) for each ID number of the raster file. For instance, raster.tif: 1 band (ID) ...
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80 views

Unable to load raster from PostGIS into QGIS

I'm trying to load raster from a postGIS connection into QGIS, but I'm getting the following error: PG: dbname=EnvModel host=127.0.0.1 user=postgres port=5432 mode=2 schema=public column=rast ...
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39 views

Create a Geotiff with different colors

I have a geotiff raster image. I have estracted the WritableRaster, the envelope, and the gridsampleDimension I need to create a new geotiff using Geotools. GridCoverageFactory gcf = new ...
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37 views

GeoServer: Use oracle as raster store without spatial extension

Is it possible to store raster data (e.g. GeoTIFFs) in an oracle table and access it from geoserver without using the oracle spatial extension/GeoRaster? I would store the images as blobs, but I don't ...
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45 views

What is the file format

I have been sent a text-file (see below) with '.txt' extension. I would like to process it in ArcGIS or any other GIS-tool. Unfortunately I do not know how to automatically load the file as ArcGIS ...
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27 views

Map Algebra with Zero-inflated regression weights

I have a non-normal count variable y and 6 rasters x1 to x6, each mapped onto a (n x n) grid. I have applied a zero-inflated negative binomial regression using the pscl package of R. I now need to ...
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63 views

How to create 10 day averages of a multiyear daily raster time series?

I have a set of daily modis LST rasters (.tif) over a roughly 13 year period (2002-2015). I would like to group them by 10 day periods, i.e. bin 1 = julian day(jd) 0-9, bin 2 = jd 10-19, etc so that ...
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34 views

ArcMap calculate statistics every time I open jp2

I have jp2 raster files, every time i open one of these files ArcMap caluclate the statistics and histogram. Can I stop this I am using ArcGIS Desktop 10.3.1
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68 views

Extract By Mask Moving Pixels

I am creating some statistics based on certain values. The issue I am having is that the extracted values are not the same as the values in the original raster. This creates incorrect output, and I ...
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29 views

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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54 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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30 views

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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29 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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27 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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33 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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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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16 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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35 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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27 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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94 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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58 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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59 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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55 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 ...
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100 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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153 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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67 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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39 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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48 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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33 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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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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54 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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109 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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59 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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88 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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49 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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105 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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158 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 ...
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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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68 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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265 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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65 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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188 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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39 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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61 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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120 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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35 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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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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86 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 ...