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

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Finding coordinates from a nested grid as a numpy array

So this is a pretty basic question, but I'm trying to figure it out. I've written a script that allows a user to read in a raster and provide a cell resolution, and outputs the amount of cells ...
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180 views

python.multiprocessing and “FATAL ERROR (INFADI) MISSING DIRECTORY”

I have a question which is closely related to this old question here: python.multiprocessing and "FATAL ERROR (INFADI) MISSING DIRECTORY" I have also looked at this, which seems to relate ...
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91 views

Can Esri ASCII Input files be Aligned with Track Heading in QGIS?

Using QGIS to input Esri ASCII data files, I uploaded many small files, each file representing a second of data: 16 sensors X 25 lines. Each file uploaded creates a small rectangle on my larger map ...
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62 views

Copying an entire column between layers (tables)

I have a raster layer with probabilities as values and I process them using the Spatial Analyst extension. After the processing the values are modified, however I would like to also have the original ...
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720 views

Projecting a Raster from WGS84 to planar Equal Area to Calculate Area: How to Select the Cell Size?

I have a broad question on how to calculate the 'correct' cell size for a raster when analyzing an area not at the equator. My goal is to project a land cover raster provided in GCS WGS84 to an equal ...
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236 views

How to render a transparent raster layer on top of one or more vector layers with PyQgis?

I been trying to render a map with a 3 vector layers and one raster layer. The idea is that the raster layer should be on top of the other 3 vector layers. The problem is that even when I add the ...
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65 views

Raster layer with unique vector for each raster cell?

I have been looking around several hours, even days, but couldn't find a clear answer to my question. I am working on a WebGIS tool that interprets local geology. From more than 70 asc-files, I would ...
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154 views

QGIS - Android, loading a .tif file

I have a .tif file I would like to use as my base map on the Android version of QGIS. However, when I try and load it as a raster layer, it states that this is not a correct raster source. Is there a ...
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164 views

Different results from Spatial Analyst GP Tool and Python

I am writing a script that has to subtract one raster from another. The rasters I have represent 1) Parking Lots (1 = Parking Lot, 0 = not Parking Lot) and 2) a buffer around the Parking Lot (1 = ...
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115 views

Raster area (QGIS) problem explained

I would like to know the area that each value in a raster has... The raster I have has values from 2-15 and I would like to know the area that each value is occupaying within my polygon... Thanks! I ...
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462 views

Are there any examples of WCS getcoverage requests done using ajax?

I am looking through openlayers to try to figure out a consistent format for generating views of coverages that can satisfy any wcs server, but mainly I'd like to get geoserver coverages. While I've ...
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143 views

Plot the Shortest Paths in a Grid without any clash at a point of time

The efficient algorithm needs to be done and proved for the best solution for the given problem: User inputs: (#) Size of the NxN Grid. (N); (#) No. of Paths: Z; (#) Source and Destination ...
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56 views

How to change the order of a raster in order to create mosaic with MosaicPro (Erdas 9.2)?

Is there a way to reorder the input files so I can control which ones are on top of the others?
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80 views

What are the characteristics of a raster to Netcdf layer in ArcMap?

Specifically, when trying to edit the attribute table? This is would be for work purely in ArcMap, and converting raster to Netcdf. I have a land cover layer (that I've converted to a raster to ...
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621 views

why preview image is blank for ImageMosaicJDBC (postgis raster) layer?

I follow http://docs.geotools.org/latest/userguide/library/coverage/pgraster.html to publish a ImageMosaicJDBC layer in geoserver. the layer seems published ok and saved, but the preview of this layer ...
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154 views

How to geocorrect in qgis?

I need to fit a utm wgs84 tiff raster to a topomap in the same projection. I use GCP and it invariably fails. The first raster uncorrected rater superimpose well, the "geocorrected" raster is ...
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74 views

Cubist Add-In for ArcMap

I'm looking for an ArcMap add-in that will create a raster based on rules from RuleQuest Research's Cubist .model files. Ideally, the add-in will give the user the option of matching input raster data ...
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168 views

Sextante - SAGA- Shape to grid question?

I have a vektor shape (Index 1-5). After using the saga tool (shapes to grid) I'm getting a raster (values 1-5). The problem is that the NO DATA area is defined as 129. Is it possible to set 129 as no ...
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184 views

Overlay Shapefile onto Geotiff

I have a Geotiff map and I want to overlay a Shapefile onto it. Ideally I want to specify a 'nice' style for the polygons e.g. have them opaque (for now all polygons should be the same). I want to ...
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328 views

Can hdf4 images be used in QGIS?

I'm trying to use hdf4 raster image in QGis 1.8. This image come from the MODIS satellite. I've loaded the file, it appears on the layer window bu it is impossible to see it on the display window. ...
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152 views

3d arcgis raster .tiff image to CFD software

i am trying to export 3d raster image prepared in arcgis to cfd package such as Fluent. I was wondering if any one has experience to convert raster image to autocad 3d format, stl, vrml or any other ...
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554 views

Output raster extents when using the Spatial Analyst Extract By Mask tool to clip a raster

I am using ArcGIS 9.2 and I have a simple python script that does the following : Loop over a polygon feature class (shown in red in the image below) For each record, create a feature layer to ...
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100 views

raster data expressed as percent

I downloaded NDVI greeness data from the USGS Integrated Vegetation Mapping Viewer. In the metadata it says that visual greenness values range from 0 to 100. My data is from the period ending 3/5/12 ...
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231 views

Importing Rasters to ArcSDE 9.3.1 using sderaster

OK, I am trying to import a raster to 11g using the sderaster command. It is a stand alone jpg with a world file associated, and pyramids. Am I right in assuming I cannot import a JPG, I can only ...
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212 views

ArcObjects .NET 9.3 upgrade to 10 breaks IRasterDataset.Copy(…) code

I have to upgrade an application from ArcObjects 9.3 (C# .NET) to 10. Unfortunately, there seems to be some incompatibility regarding the IRasterDataset.Copy method. The following code worked fine in ...
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305 views

Create custom pixel block size in ArcGIS 10?

I'm using the new IRawBlocks in ArcGIS 10 from the adopted sample in ArcGIS 10 SDK help and I want to create a custom sized pixel block that feeds me a block of values column by column instead of a ...
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214 views

Process to gather raster cells under features

I need to gather individual raster cells underneath a feature in a featureclass as quickly as possible. It seems that most ArcObjects functions have problem with island polygons, multi-part polygons, ...
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25 views

How to avoid “Unable to compute a transformation between pixel/line”?

I am trying to re-project from Equi-rectangular to the NASA global EASE grid (Equal Area Scalable Earth) grid 1383 586 with a ~25 km cylindrical projection (ESPG=3410). The file is provided as HDF5. ...
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21 views

Where to find QGIS geoprocessing results?

Is there a way to access in QGIS 2.6.1 something like the Geoprocessing Results window found in ArcGIS? The History and Log window in QGIS appears to show the geoprocessing results from SAGA, OTB ...
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13 views

QGIS - r.* commands not found

I'm very new to GIS and have recently installed QGIS on my mac desktop computer, running Yosemite 10.10. I'm working with DEM data for stream network extraction, but the majority of grass raster ...
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25 views

How to OCR topographic maps

I have old topographic maps that i have scanned and converted into pdf in Actobat XI 11. I need this pdf to be text-searchable (not mere image). To do this i tried text recognition in acrobat but it ...
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15 views

Python Script to iterate numerous, single-band rasters for arcpy.CompositeBands

I have a large collection of single-band geotiffs (NIR, Green, and Red) that I would like to composite using a Python script. The goal is to iterate through multiple folders in a main directory, ...
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32 views

QGIS - quickly style categorical map

Example situation: a raster map that denotes various provinces in a country, each indicated with a unique value. Goal/question: quickly (for 'preview' purposes, not making a publishable map) assign ...
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19 views

Calculating Autocorrelation in Different Zones

I'm an intermediate-ish user of ArcGIS 10.2 (win7 pro, hardware robust enough to handle very large datasets and computationally intensive analysis) with perhaps a simple problem that's evading me ...
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28 views

How legitimate is smoothing raster data that has been converted from polygons?

I am interested in applying this methodology to census block data after conversion from a raster: http://rutgerscps.weebly.com/uploads/2/7/3/7/27370595/censusdatasmoothing_brief.pdf Basically, the ...
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35 views

GRASS GIS r.walk issue

I have been playing around with GRASS GIS to do a simple cost analysis of getting from point A to point B. I have a DEM clipped to the study area, a raster containing the friction costs, as well as ...
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47 views

Add Surface Information alternatives in QGIS?

Is anyone aware of a single tool or possible routine of tools in QGIS (2.6) which emulate the results of the ESRI 3D Analyst tool 'Add Surface Information'? I have several polygon shapefiles (some ...
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19 views

Extract by mask/copy raster a RGBA (4bands) raster results in a greyscale image in photoshop discarding all RGB composite info

I used a polygon Shapefile to extract by mask (ArcGIS) the sea area from a RGBA (4 bands aerophoto) raster. The Extract by Mask caused up-sampling from 16 bit (my raster's initial pixel depth) to 32 ...
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28 views

Performing Maximum Likelihood Classification in R

I'm trying to perform maximum likelihood classification of landsat imagery using R, I have been searching for a package that implements it but so far I haven't found it. What is the easiest way to ...
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33 views

Calculate surface map from PostGIS

We need to create surface maps from the website. The data is stored on PostGIS (2.1) as a table of Point geometries with a field indicating a thematic value. The optimal solution would be to produce ...
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39 views

ArcGIS Split Raster tool results in black rasters

I have a rather large raster that I am trying to split into small tiles in PNG format to upload to Autodesk Infrastructure. I came across the Split Raster tool and thought it would do exactly what I ...
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19 views

Problem with QGIS raster interpolation from a point shapefile after duplicating the shapefile

Let me explain a problem I had with QGIS to see if somebody else has experience it. I created a raster from a point shapefile through the Raster-> Interpolation menu with no problems. After that, I ...
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43 views

Does interpolation create a vector or raster?

I have been reading about interpolation and am trying to understand whether interpolation results in a vector or raster. Say I have a layer of points and I am interested in creating a raster that fits ...
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36 views

OpenLayers/Geoserver - can I create a tiled, zoomable raster layer?

Still a relative newbie with Geoserver and OpenLayers. Developing an application with Geoserver in the back, OpenLayers (3.0) in the front. I have a requirement to display imagery on top of a base ...
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42 views

Add Rasters to a new GDB/Mosaic Dataset in ArcGIS ModelBuilder

I'm attempting to add rasters to a new mosaic dataset in a new file geodatabase, all in the same model. However, the Add Rasters To Mosaic Dataset tool does not recognize the NewMosaicDataset or the ...
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75 views

ImportError: No module named gdal qgis2.8.1

i am using QGIS 2.8.1 (32 bit) in windows 7). I imported two DEMs and trying to merge (QGIS>Raster>Miscellaneous>Merge)them. Unfortunately it gives me import error as below. Traceback (most recent ...
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21 views

How do you symbolise a 32-bit raster in ArcObjects?

For rasters that are ABOVE 16-bit - you cannot apply a colormap - so what is happening when you symbolise in ArcMap a 32 bit raster, it's certainly possible. I'm trying to emulate this funcitonality ...
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29 views

Worldfile incorrect? Puzzler: all resources supplied!

Trying to manually create a worldfile for gif images of surface currents supplied by the navy here. I have QGIS and am decent at using it but the world file tool is failing without error on me (even ...
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48 views

Metric maps vs topological maps for path finding and UI rendering of indoor floor layouts

I'm building a software to map indoor floor plans of large facilities (like malls). I read through some of the questions on this forum, but my constraints are a little different than the ones ...
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36 views

SAGA GIS - raster image from Civil 3D

I am a new user of SAGA GIS software. I need to interface the Civil 3D 2015 and Hec Ras software in order to create a flooding map. In order to put in communication the two softwares, I have to use ...