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

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Corrupted rasters after import into ArcGIS FGDB

I have been seeing a number of corrupted rasters recently after importing them into file geodatabases (FGDB). The image below left shows a .tif prior to the import, while the image to the right shows ...
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533 views

How to add ECW support to GDAL bundled with PostGIS Windows

I'm currently trying the new raster functionalities of PostGIS 2.0 and I successfully imported some GeoTIFF file into PostGIS (although it only find one band so it's all black and white for some ...
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77 views

Make a thumbnail of a raster in PostGIS

I'm fiddling around trying to create a thumbnail of a fairly large (originally 27MB) raster, chunked into 64x64 blocks. I've got the following and it works, quite well, but I'm wondering if there is a ...
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132 views

identify the fraction of raster cells and listing all the cell values in every polygon

In Arcgis 10 I have a netcdf file that maps the fractions of cropland in the world from 1700 to 2007. I extracted the years that i needed as raster layer format (continous data from 0 to 1) and now, ...
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703 views

ArcGIS 10 - disappearing rasters?

From time to time it happens to me that rasters disappear at certain zoom level in ArcMap, or only some parts of the raster (strips) show up. I'm working on WinXP, ArcGIS / ArcView 10, Sp2, rasters ...
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50 views

How to recreate the 'standard deviation' option for a raster layer in Mapserver?

In mapserver is there any way to recreate the 'standard deviation' option available in Arc's symbology for a stretched raster layer?
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58 views

Guide for esriRasterOpCode

I'm building dynamic cartographic symbols to display inside ArcMap, but they are displaying "wrong". Is there a guide somewhere that will show what raster op code does? I mean, not only show, but ...
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321 views

ValueError when reading a raster band as a numpy array

Here's the problem shown in Python shell: In [32]: from osgeo import gdal In [33]: geotiff = '/Users/calvin/work/luc/proj_public/media/GLO ...
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161 views

Can I overlay layers in Dealul Piscului 1970 and WGS84 in QGIS?

I have a 10 Gb ECW file (mosaic of a whole county) that is in Oblique Stereographic projection with Datum: Dealul Piscului 1970. The problem was that no matter the Default CRS for new project was, ...
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160 views

How to retrieve the value of a cell in RasterLite?

Just wanting to know the SQL statement needed to find out the pixel value for a location, when the raster is loaded into SpatialLite as a Raster? I loaded the Raster using rasterlite_load -d ...
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141 views

How to get SplineWithBarriers to work in C#

I have been having fits trying to get SplineWithBarriers to work but to no avail. My environment: Windows 7 64 bit Visual Studio 2010 Team Edition ArcMap Release Version 10.0 Product Version: ...
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200 views

vba code for algorithm to assign track file gps UTM coordinates (East Africa) to an overlay 5x5km grid cell

The GPS coordinates are temporarily imported in to an Access database from DNR Garmin files downloaded (as dbf file(s)), and then exported for mapping in AEJEE (ArcExplorer Education Edition). I need ...
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241 views

Assign Custom Band Combination To Image Catalogs In ArcGIS

I have an image catalog composed of 4 band rasters. I would like to use the same image catalog, and set custom renderers for a true color and false color combination and save each of those catalogs ...
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650 views

Conversion to Raster issue in ArcGIS 9.3.1

Trying to convert a polygon to raster in ArcGIS gives me an error... I am wondering if there is another way around to do this? I am using ArcGIS 9.3.1. The error i am getting is number 9999 when I ...
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322 views

16bit grayscale raster displays all black in Geoserver

I have a 16-bit raster (MrSID) that I want to display in Geoserver 2.0.2 but it is displaying as all black. If I create a new style similar to the default raster.sld but with graychannel element the ...
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684 views

two results of IDW in ArcMAP are different

i added the following points to ArcMAP using "Add XY Data". x,y,z 7,39,117 27,17,122 27,61,123 46,36,136 52,14,138 55,46,141 56,56,137 65,24,144 65,36,145 Changed raster output size in "options" ...
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10 views

Updating/replacing GeoTiff data store on file system causes GeoServer to halt

I have a few hundred raster layers that are updated at least 4 times a day. The GeoTiff's are updated directly on disc. I'm running it as a windows service and I can sell the wrapper app logging the ...
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18 views

A Distributed Cost-Distance Algorithm

I'm currently trying to implement a distributed cost-distance algorithm, however I can't seem to invent my own and still make it fast. I've been googling around a bit but haven't found anything that ...
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16 views

Raster import problem

I have raster images (orthos) and feature layers in a GIS program (Global Mapper). When I import these files with the same CRS into QGIS they are literally 9000 miles apart and I cannot figure out ...
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11 views

How to summarize canopy cover at a minimum mapping unit using ArcGIS

I am working with Landfire data and I have a project which requires that there be no area under 10% canopy cover at a 5 acre scale. I am going to use the Landfire CC2010 data and use a 5 acre moving ...
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30 views

Scatter plot of two rasters in arcmap for intersecting cells

How do I make a scatterplot of two rasters in arcmap which will plot the two rasters' cell values of the same cell against each other (for every cell where they intersect). I need to first create a ...
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15 views

Has anyone success using subset an image such as NAIP?

Has anyone any luck subsetting a small part out from NAIP? I'd like to hear your feedback on pros or cons on how to subset an image from NAIP despite they are in mrsid and their uncompressed file size ...
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37 views

Creating a Raster of Road Distance to Point

I am using QGIS 2.6. This question is in two related parts: I'm trying to create a raster of travel time from one point to another point travelling via the road system. Each raster pixel will roughly ...
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65 views

QGIS raster symbology problem in 2.6

With the new 2.6 QGIS version I often have problems with raster colors. For some reason certain pixels do not display initially, but if I move the raster a little spatially they show up.
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22 views

Adding Raster Layer in C++ application always result in layer invalid

I am trying to add a raster layer in c++ application with QtCreator and QGIS 2.6.0. My code is as follows: QgsRasterLayer * layer = new ...
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53 views

Reclassify raster value

I'm curious if anyone has been able to change one individual value in a raster file? I'm using Arc 10.2 and trying to change the value 99 to -2 for 144 files using model builder. So far, I've only ...
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12 views

Change “World Size” with gdal2tiles.py

When I use the flag "-p 'geodetic'", the output is a world that is 512x256px at zoom level 0. In order for it to overlay with other datasets, I need it to be 640x320px at zoom level 0. I am looking ...
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22 views

Script Efficiency

I have been working on a script to read pixel values and print the values out to a text file. This is currently working but takes around two hours with a 6.6gb file. This is to replace an older script ...
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38 views

Apply raster contraints on single table with multiple files

I have a raster table (pre-created using CREATE TABLE) containing multiple individual raster files that I append piece by piece to a final table. The table itself is in its own tablespace 'gisdir' and ...
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31 views

Error: Cutline feature without a geometry. > Raster Type

I've got an "Error: Cutline feature without a geometry" on QGIS 2.4.0 Chugiak. I have 2 samples (A raster type and a vector type), they have the same coordinates (EPSG:4253 - Luzon 1911) Then I tried ...
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9 views

How to implement gs:storeCoverage with GeoServer scripting

I was wondering if it is possible and how to implement the service gs:storeCoverage using the scripting facility (e.g. with python or groovy). The reason I ask is that gs:storeCoverage is not of ...
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32 views

WPS: how to write output to a raster layer in GeoServer

In GeoServer vector-based Web Processing Service (e.g. gs:Import), we can have the output saved to a GeoServer Layer, as described in the documentation. Outputs Name Description Type ...
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41 views

Creating spatial Reference to ASCII file

I have produced ASCII files in MaxEnt. These files are able to be loaded into Arcmap10.1 and display as an image, but i cannot interpret them or create them into a polygon for further analysis. I have ...
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21 views

Update Raster extent

How do you update raster's extent after you export the raster ? I forgot to enable the Date Frame rather than it's original Dataset ? Thanks.
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20 views

PostGIS raster write support in R

I want to push/write some generated raster layers to my postgres database directly in R. In theory this could be supported by the rgdal package, but sadly it isn't. In the latest version only copy, ...
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39 views

Problem with Raster Calculator in Model Builder

I have created a model which repeatedly uses the raster calculator. My problem is that unlike that of the other tools, the output name of the raster calculator does not change. This means that I can ...
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45 views

Find correct SRID

I'm learning PostGIS raster, and importing GeoTiff with raster2pgsql. This command line tool states: -s <srid> Set the raster's SRID. Defaults to 0. If SRID not provided or is 0, ...
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45 views

Setting raster resolution in meters when working in a Geographic Coordinate System

I work in WGS 84 (Geographic Coordinate System) in ArcGIS 10.1. I need to create a raster specifying its cell size in meters, and output it in WGS84. Is it a good solution (towards a less shape/area ...
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13 views

What do pixeltypes in PostGIS raster mean?

I'm trying to build a raster in PostGIS from a vector layer and I was curious as to the meaning of pixeltypes in the raster geometry? How does it effect my raster?
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26 views

Interpolating points to surface not working

I am trying to create a surface from points using IDW interpolation. Have tried both 3D analyst and Spatial Analyst tool with my selected xyz data sheet. It appears to process and I don't get an error ...
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88 views

How to correctly render a raster Layer to GTiFF with QGIS python console?

I am trying to render a map from a raster layer. As recommended in pyqgis cookbook and here(osgeo.org) I use QgsMapRenderer(). I am able to produce a picture but it has not appropriate extent and ...
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47 views

IMG and geoTIFF raster extraction

everyone. I'm very new to GIS technologies. Somehow, i need to extract raster(RGB data) data from geoTIFF and IMG files. What is the fastest way doing it?
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43 views

Ortho-rectification of Aerial Image

I took an aerial image of our farm using RC quadcopter. How am I going to orthorectify this image? Please can you help me with detailed instructions/methods involving the process.
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80 views

Merge/mosaic categorical rasters in QGIS/GDAL

I am attempting to make yearly bins of some monthly MODIS data for all of the US. The cells of the raster are defined with Julian dates indicating the date at which a burn event took place. After ...
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48 views

Positioning and tracing polygons over an image

On QGIS 2.0 - I want to add an image (TIFF or whatever) then resize and correctly position it over a satellite image (openlayersplugin). Then, the task is to create a new shape file layer and draw ...
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44 views

analysis of srtm data for gaps

I need to analyse the SRTM DATA (1025 X 1025) of a particular terrain which has gaps or voids. Could anybody suggest a solution to find the percentage of gaps or voids in the SRTM data? I would like ...
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51 views

Create global raster layer with latitude values of each cell in QGIS

I have a raster with a 0.0083 degree resolution (WGS 84) of which I need the area of every single pixel. An easy but compute-intensive approach is explained here but as I need to work with bigger ...
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24 views

Text in POSTGIS Raster

Is it possible to add text/annotation to a raster generated in Postgis raster? Specifically I need to do this within the database if possible and am looking for an option that does not require an ...
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63 views

Polygonize only pixel values of 1 from a raster

I have a raster mask that I have created in QGIS (2.2.0) that consist of 0, 1 and nodata values. I would like to end up with a polygon dataset that consist of only the value of one pixels from this ...
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57 views

How to reassign the values of a raster, based on the pixels of the raster beneath it?

In ArcMap 10.2.1, I have two rasters. Raster1 shows the extent of a habitat, and each pixel contains a categorical value for its land cover type (values 1-3). Raster1 has the smaller spatial extent of ...