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

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Cell Statistics in QGIS

Cell Statistics in ArcGIS will calculate the mean (or statistic of choice) among multiple rasters on a cell-by-call basis. Can QGIS do this? If so, how?
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Can I tell QGIS to load/show only a part of an image?

can I tell QGIS to load/show only a part of an image without to extract this region as an extra/ new image?
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49 views

QGIS 2.01 - raster transparency not working properly

I have loaded a color raster image (aerial orthoimagery) into a QGIS project. The layer is visible but very transparent (in the enclosed image the vector polygons are below the imagery), but when I ...
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49 views

Is there any GRASS command to measure the distance between a point in rastermap and another in vector map?

I have a question about WinGRASS 6.4.3. Is there any GRASS script command to measure the distance between a point in rastermap and another in vector map? I have a raster map and a vector map. Raster ...
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86 views

Extra row and column in a raster after GDAL grid import

I'm exporting an ESRI grid to TIFF format and after that I'm reading this exported raster file into SAGA GIS. However when Saga reads this file in there appears to be an additional row and column in ...
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217 views

ArcGIS Mosaic to New Raster() tool seems to interpolate data gaps on one computer/version but not another?

i have a group of raster files in .tif format that I want to mosaic together into one .tif. I've noticed that I get data gaps along the seams when I do Mosaic to New Raster() on my home computer ...
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178 views

QGIS 2.0 Problem with loading a Layer Style file that contains a transparent pixel list

I work with QGIS 2.0.1. For my raster file I have created a Layer Style with a transparent pixel list. When I import a rasterfile in a new project and load the layer-style file, the map changed to ...
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127 views

Fill tool creating large output files from sections of a Raster

(This raster information for one of the clipped rasters) I have a raster image representing a landscape that is about 1.3Gb. I clipped the raster into 31 sections which vary in size from 10Mb to ...
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81 views

Write raster with its attribute table and symbology

I am classifying lots of rasters and I'd like to automate the legend creation and symbology displaying for easy manipulation. Here is the kind of raster I'm dealing with: library(raster) r <- ...
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265 views

TIN to Raster Tool, output elevations are 3.40282e+038 and -3.40282e+038, tried calculate statistics didn't work

I have an input TIN file that I created using Create TIN. The elevations are all correct. When I convert the TIN to Raster using the tool, my output elevations are 3.40282e+038 and -3.40282e+038 ...
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93 views

Importing GPS coordinates to extract multiple DN values in ERDAS

I have a set of GPS points (stored as a csv for now) and would like to import these points to ERDAS to find the DN values associated with each location. I am able to import a SHP to ERDAS but the ...
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79 views

Qgis raster interpolation shift

Using Qgis 2.0.1, I'm attempting to interpolate a large point dataset (n > 400K) to a raster surface. I'm using the IDW option in Raster>> Interpolation>> Interpolation, and the resulting ...
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148 views

Why doesn't the mosaic to new raster tool or the mosaic tool work when I try to use them?

I am trying to mosaic 4 raster datasets of elevation together using the 'Mosaic to new raster' tool in ArcGIS 10.1. I have even tried using the 'mosaic' tool and it still doesn't work. The errors that ...
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86 views

Making spatial clusters by direct manipulation of raster pixel values using R

I think this is an overambitious million dollar question, but I'm always optimistic when I pose a question even though I feel like I left no stone unturned! I've processed a raster layer with pixel ...
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153 views

PostGIS Raster: raster2pgsql was not found in /usr/lib/postgresql/9.3/bin

I have installed sucessfully Postgresql-9.3-postgis on Ubuntu 12.04, following this instructions: http://trac.osgeo.org/postgis/wiki/UsersWikiPostGIS21UbuntuPGSQL93Apt Having done that, I have ...
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61 views

Color blending/compositing in web mapping frameworks?

The color/layer blending capabilities of QGIS 2 produce marvelous results. Blended rasters are especially nice to look at. Blending is, to me at least, a better way of combining layers than mucking ...
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88 views

Mann-Whitney U test for rasters

I'm doing a Mann-Whitney U test to compare two very large samples (sample size 1 = 13250; samlple size 2 = 38871) originating from a shapefile with 52121 features. I know t-tests are not recommended ...
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151 views

How to write script for Line of sight and Viewshed analysis in Global Mapper

I wanted to write script in Global Mapper for Line of Sight and Viewshed analysis. I tried to calculate using Viewshed and Global Mapper Tools but the issue I am facing is that analysis is user ...
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132 views

How to Iterate ModelBuilder for Zonal Statistics?

I want to use ModelBuilder to split a DEM into multiple tiles, then run the iterator on each tile made for the Zonal Statistics tool to find the highest point(s) in each tile and give these as an ...
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131 views

Why are the colors of my WMS layer messed up in QGIS?

I have a raster image on my computer, and I used it to test some geoserver features. (I'll upload images to show you what the problem looks like) I have the same raster, but transferred by wms. And ...
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42 views

What type of calculations must be done for traffic emission for buffers in land use regression?

I have a raster layer that shows traffic emission distribution by kernel density method. Traffic emission will be used as independent variable in land use regression. What type of calculations must ...
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124 views

Touch up tool for rasters?

I was wondering if it were at all possible to manipulate/massage rasters (eg Geotiff) using Qgis plugins or Grass?? By manipulate, I mean manually smooth off interpolation artefacts, blended surface ...
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235 views

Saga Reclassify grid problem

I am using Qgis 2.1 ver. 5f5cd4c (64 bit version on win7 64) OSGeo installed. I was trying to reclassify a DEM in EPSG:32614. I used the SAGA's Reclassify algorithm in the processing toolbox. I ...
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Selecting a bounded area within a raster

I am new to postgresql. I have imported a 256kb sample raster (.tiff) into postgres with tilesize 100x100. Now I need to select the area (rectangle) from the center of the image using sql query. Then ...
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Layers and variables are not coming out in the raster calculator tool window

I have many shapefiles in the table of content but layers and variables are not coming out in the raster calculator tool window. I placed the cursor the left of the Raster Calculator window, dragged ...
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62 views

Sending Raster File in ArcMap, Attributes Gone

On my computer, I opened a .tif file in ArcMap 10.1 and reclassed the values into two categories - this results in a new file. I then send that file to another computer and open it in ArcMap but ...
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51 views

Selecting a rectangle box from a raster tiled table in PostGis 2.1

I am new to PostGIS as well as SQL queries for rasters. I have imported a raster .tif file into PostGIS with tiles. I would need to select a bounded rectangle from within this raster using SQL ...
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144 views

GDAL and Python: How to “pad the extent” or otherwise handle band.ReadRaster() for area falling slightly outside the image bounds?

In a nutshell, I'm trying to create a bare-metal tiling utility using GDAL and Python. As you can see in the graphic below, which shows the perimeter of a raster and the OSM-structured tile index, ...
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123 views

Interpolating shapefile of points to grid using Java?

I am looking for a method/prog/library(java) to interpolate points from a shapefile to a grid (file). I have seen arcgis can do that but i am looking for something free. More specific: i have ...
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183 views

GDAL in Java fails on ReadRaster()

To summarize, trying to read a raster keeps giving me an UnsatisfiedLinkError that makes sense, but looking into the compiled GDAL jar, I don't know how to fix. gdal.AllRegister(); TheFile = ...
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the layer attribute table is not consistent with the pointvalue

The point value of my grid is right, but the output value ranges from -2147483648 to 2147483647. I haved tried to recalucate statistics, but it didn't work..
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203 views

How to add new raster store and publish for ECW fromat in GeoServer 2.4-RC2?

I am using GeoServer 2.4 RC2 and Tomcat7 on windows xp OS. I have extracted the gdal-data.zip (2.4.0) and geoserver-2.4-SNAPSHOT-gdal-plugin into Tomcat 7.0\webapps\geoserver\WEB-INF\lib. Now ...
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216 views

validating the calculation of slope from DEM

my purpose is to calculate and validate slope in percentage of southern california using DEM and landsat data. step 1)i used a DEM file and changed with the float type file to integer type step 2) i ...
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163 views

Modifying Raster Layer with Python Console

Forgive me if this has been asked somewhere else. I am looking for a way to edit a raster file which has already been loaded into QGIS through the python console (i.e. I would like to edit the raster ...
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62 views

grass region resolution error

I am working on a raster, but I can't set a correct region for it. In the Set region to match this raster map field, I select my raster map to change current region, but its resolution does not ...
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165 views

How to perform Shapefile to Raster with ArcMap 10.1 while preserving resolution and values?

I am new to ArcMap and I would really appreciate some help. I want to create a new raster using a value in a column of a point shapefile. I have a point shapefile with points equally spaced and each ...
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Add Raster To Mosaic Dataset: Could not recommend a data source crawler for the specified input

I'm trying to add rasters (TIFF) to a Mosaic Dataset after adding some rasters, the process fails with the message. ERROR 999999: Error executing function Could not recommend a data source crawler ...
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392 views

How To calculate raster land cover inside overlapping buffer zones?

I am working with a raster land cover file that consists of several land cover types (e.g. forest, buildings, grass ect.) in total there is 40 different land cover types. I have 1200 bufferzonen ...
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110 views

convert vector with multiple attributes to multiple rasters

I have a vector polygon feature with multiple attributes/fields. Ultimately, I want to convert it to a raster 'stack,' whereby each of the attributes/fields will be a different band of the raster ...
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116 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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103 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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331 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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167 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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47 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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760 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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Color Ramp of Raster Rendering in MapServer

Does this proposed new syntax work yet? http://mapserver.org/development/rfc/ms-rfc-6.html#proposed-new-syntax Currently, I am still using this method for rendering the raster in Mapfile. STYLE ...
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150 views

Python Script Producing Empty Cost Path Rasters

I'm trying to run a script that will create cost paths for a large number of randomly generated points then assign the cost to those points. But my script is beginning to create cost path rasters ...
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Why are the Raster z-value changed when reprojecting?

i have raster data with height values (z). when i try to reproject/warp the raster to gauss kruger 3, the z-values are changing (several meters). (the data is already gk3, but i have to reproject ...
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164 views

ArcGIS Spatial Analyst “Sample” returns Null values

Using "sample" to join raster values onto point data, some of my points get assigned a Null raster value. The raster does not contain Null values and definitely looks like it has a value at the ...
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How to load a raster from in-memory bitmap (not from file) into PostgreSQL

I have a bitmap in memory that I would like to load as a raster to PostgreSQL. An unfavorable option is saving the bitmap to file and then use raster2pgsql, but as we have several cameras that ...