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

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QGIS Export section from raster to AutoCAD

QGIS Windows 7 I have a raster which displays the flood depth over my site. What i would like to do export to AutoCAD an outline (maybe as a polygon or line) of the sections of the raster which are ...
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52 views

Clip .hdf (MODIS) rasters by shapefile

I am trying to do a temporal analysis on vegetation quality so I downloaded a MODIS .hds raster from earthexplorer. When I opened the file into ArcMap 10.2.2, it came as a group of 11 rasters. I stuck ...
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86 views

For loops + boxplot for raster

I have several Rasterstacks (b1_mask, b2_mask,...) of several layers representing only a determined pixel-intensity range. (So point "A" in some layers is "NA" - in others a "value" of that certain ...
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46 views

Reference raster data outside of GeoServer data directory

is there a possibility to point GeoServer to raster data stored neither in a database nor in the data directory of GeoServer? My problem is that IT keeps me from direct access to the GeoServer ...
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89 views

how to use raster layer (map image) as base layer in geoserver+openlayers and vector layers on top of that?

I am using Openlayers + Geoserver for rendering data on India Map. I am able to do it. However, the India map generated from Opensource shape files doesnt look good. So, I want to use Better India ...
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37 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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66 views

How to speed up raster/map algebra in PostGIS?

I am testing map algebra with PostGIS (2.1 with PostgreSQL 9.3) on two images, and found it to be rather slow. For example, dividing two images of 7200 * 3600 pixels took 110 ~ 120s on a desktop with ...
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262 views

How to build an attribute table in a 3-band raster?

I have a 3-band (RGB) raster file from CORINE and the attribute table hasn't been built. When I try to execute the command BuildRasterAttributeTable I get an error that only single band rasters are ...
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41 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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92 views

Using same line to interpolate multiple rasters, and put all profiles on same graph, using ArcGIS for Desktop?

I'm new to the website and new to ArcMap so please bear with me. I'm struggling with the "interpolate line" function on ArcMap. Long story short (hopefully): I have some bathymetry rasters of an ...
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23 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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19 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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113 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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40 views

How to create this raster?

I have three layers: building data (polygon) attributed with parking lot capacity on the road parking data (line), also contains parking space data car parks (polygon) includes parking space ...
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19 views

Converting a table to a raster for clipping

I have a series of tables (TAB files) that represent the calculated values for a corresponding .tif image. These tab files have the same number of rows and columns as pixels in the tif images. The ...
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28 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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67 views

Remove sections, defined by a line or polygon, from a raster in QGIS

(QGIS 2.6.0 on Windows.) I have created a raster layer of heights using the TIN interpolate function. I also have another raster layer with more accurate information on the height of particular areas ...
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37 views

Creating new raster based on spatial extent and classes of one raster and average of another using ArcMap?

I have a raster that is split into classes and I wanted to make a new raster with this raster's spatial extent and classes but displaying the average values from a different raster. I am not really ...
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73 views

Modifying raster values in a zone with a math expression

I'm currently doing an SIG project with the goal of calculating groundwater volumes in chalk and silex residuals aquifers. I have point data of underground water, chalk roof, and floor elevations, as ...
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107 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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36 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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38 views

Will Processing without a Spatial Reference cause Issues?

I was given a bunch of ASCII files that I needed to convert to raster and then create maps from. For some maps I had to do a simple difference calculation between two rasters (did this in ArcMap). ...
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112 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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163 views

problem to open a netCDF and create a raster file

I want to open a netCDF file and create a raster with ArcMap 10.2. The file contains the mean monthly temperature for Switzerland. I found it in meteoswiss web site. I tried to open it with the ...
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27 views

Accessibility indication from points

I will simplify my question to be better understood. Let's suppose my study area is consisted by settlements A and B. They both have the same population (1000 people each). Each settlement was ...
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26 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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134 views

error invalid output extend in zonal statistic

i have a problem with arcmap10.2...i have a dtm(that now has dimension of the pixel 1000) and another raster whit the same resolution with the code of a specific area..what i want to do is calculate ...
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134 views

how to batch reclassify rasters with percents range

Using Model Builder I need to reclassify slope rasters with percents range value. I have read and ask here batch reclassify rasters with different elevation ranges, but I still need more explanation. ...
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23 views

Clipping MrSID raster image, without decompressing clipped raster, in ArcGIS Desktop? [duplicate]

I am using ArcView ArcMap10 and when I clip a raster using tools/data management tools/raster/clip. The Clipped file ends up much larger than the original file. Specifically I am trying to clip a ...
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23 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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51 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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51 views

How to update raster metadata in postgis

How can I update the raster metadata in postgis? upperleftx | upperlefty | width | height | scalex | scaley | skewx | skewy | srid | numbands ...
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19 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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25 views

Exporting QGIS Raster/Vector layers into one PDF? [duplicate]

I have seen a similiar post to this a while back (Is it possible to export GeoPDF from QGIS?), and thought I would try asking it again to see if there has been any improvement or new knowledge on ...
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83 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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27 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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37 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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151 views

How to load postgis raster layers into R?

It is easy to get Vectorlayers into R from a PostgreSQL+PostGIS solution. library(rgdal) dsn="PG:dbname=plots host=localhost user=test password=test" plots = readOGR(dsn,"Plots") But how to do the ...
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57 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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104 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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105 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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40 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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31 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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1answer
251 views

Determining the slope of a DEM (SRTM-data) in QGIS

I'm new to QGIS and I have to calculate the slope of a DEM (I use srtm-data). I already detected the geoalgorithms toolbox and I also produced a raster layer with the slope using the tool "slope, ...
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151 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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53 views

Aggregating rasters with GDAL

I have a set of files that have been mosaiced into a global VRT in a particular projection and resolution. However, I have a need to report statistics on a (say) one degree grid, where the reported ...
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59 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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74 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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32 views

How to smooth raster data? [duplicate]

I want to print a map of an island based on SRTM data but the basic raster layer looks pixelated especially at the transition to the ocean. Is there a way to smooth it?
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146 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 ...