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

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Raster calculator error 000539 - cannot create weak reference to 'classobj' object

I was - like many times before - trying to clip a raster with the raster calculator (raster * 1 with shapefiles as mask). Now - the following error keeps popping up: ERROR 000539: Error running ...
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38 views

Raster Attribute Table Where Each Pixel = 1 Row

In ArcGIS, is it possible to create a raster with an associated attribute table where each pixel is represented by a "row" in that table. I would like to specify unique attributes for each raster ...
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18 views

Calculating Percent Overlap Between Distribution Maps

Hello there, I am currently trying to calculate the percent overlap (basically the total amount of overlap where these two species come into contact) between Lithobates catesbeiana (first image) ...
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1answer
52 views

Cell Size of Raster Explained

I'm not quite understanding the cell size values that a given raster has. I been doing some kriging interpolation on some very dense point data and if I leave the cell size parameter blank, it's cell ...
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1answer
24 views

Polyline frequency to raster

I have some animal tracking data in the form of a polyline shapefile and want to convert this to a raster so that each pixel is given a value of 1 for every instance in which a line crosses it. I've ...
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1answer
73 views

Hillshade tool in ArcMap returns terraced, pixelated image

I am applying Hillshade tool (ArcMap 10.1) to SRTM in Caucasus Mountains (border between Russia and Georgia). It gives me weird image with 'terraces' (see attachment). I reprojected SRTM from WGS-1984 ...
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2k views

How to get hypsometric curve from elevation data?

I have my elevation data but cannot make an attribute table from it and so I'm not sure how to get any of that data into a table in order to make a hypsometric curve.
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2answers
85 views

Grass GIS 6.4.3, How to create a .PTS file

I'm trying to export a raster map in order to use it in the Flo-2d program. This program needs a .pts DTM file, do you know how I can create it? Alternatively, I can use a XYZ file looking like this ...
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1answer
49 views

How to create graph out of two layers using ArcGIS 10.1 for Desktop?

I would like to create a graph of two layers I have. on one hand its the land price of a certain area and on the other a layer with a crime rate. first of all, the layer with the land prices doesnt ...
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2answers
33 views

How can I get my raster analysis to produce a larger extent in ArcGIS

Ok so the situation is as follows. I have an vector shapefile and within that area there are three points. I converted the points into raster and now I want to do a Euclidean distance analysis in ...
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1answer
105 views

How to add tree height values to raster / vector data?

I am new to working with raster data and I am trying to teach myself a few things. I have what I think is a simple problem but I can't seem to figure this one out after a few hours of searching Arc ...
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1answer
42 views

Why do the raster band values have different values than the raster statistics?

I am working on a raster file (1 Band). According to the raster metadata, my minimum value is 0 and maximum is 7458. This seems to be confirmed by the Style options that return some category values ...
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190 views

How to convert multiple rasters to new raster (mosaic)?

I want to use Mosaic To New Raster in ModelBuilder. I want it to give me multiple outputs because I have multiple folders with a different number of images in each. Below is the model that I have ...
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1answer
236 views

ArcSDE - How to edit mosaic dataset

I have a mosaic dataset (Raster) in an SDE database. As expected, when I click start editing, ArcMap says that I have to do "Register as Versioned" before, but I can't have a mosaic dataset in a ...
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1answer
32 views

Find maximum and minimum value in a list of raster

I trying to write a standardisation script that standardises each raster dataset in a list of rasters by the highest and lowest values found in the list of rasters. The standardisation code is as ...
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23 views

Continuous color band for a raster legend in QGIS composer legend

I'm looking for a way to insert continuous colour legend for a raster layer. I managed to create discrete symbols with values along the bar, but I would like to have a continuous bar with some values ...
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3answers
104 views

Topography: How to get the x,y,z coordinates of highest or lowest point/pixel of a raster GIS?

Given a .tiff topographic raster image with mountains and deep sea, I am looking for the x,y,z specifics of the highest or lowest point. The x,y,z values being: altitude (z-coordinate) latitude ...
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28 views

Extract raster values under under each polygon buffer in qgis

In qGIS: I have raster file and >100 points. I constructed buffers polygons (vector-->geoprocessing-->buffer) around each of the points. Than I clipped (raster-->extraction-->clipper) the raster file ...
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1answer
62 views

Map algebra for loop

I have never coded in Python before and I am trying to loop a simple map algebra equation across 365 rasters. I am trying to calculate total water flow over cells but in the raster I have a negative ...
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1answer
30 views

Extract information of a raster overlayed on another raster with a lower resolution directly in python

I have two aligned rasters with the same extent, one has a resolution of 5 meters and the other of 125 meters. I would like to place the 5 meter one over the 125 meter one and assign to these smaller ...
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1answer
138 views

Calculate area covered by a particular raster layer within polygons in QGIS

I am trying to extract information on vegetation cover within a set radius of point locations (my sites). I have succeeded in creating a new vector layer of circles with a 5 km radius around my sites. ...
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1answer
45 views

Fill sinks error in arcHydro

I am working on a project that is modeling runoff at a county level. The DEM used is lidar derived and has a 5 ft resolution. The general workflow I am flowing is Sink evaluation Sink Selection (to ...
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2answers
720 views

FOSS method to split raster into smaller chunks

I have a raster (USGS DEM actually) and I need to split it up into smaller chunks like the image below shows. That was accomplished in ArcGIS 10.0 using the Split Raster tool. I would like a FOSS ...
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2answers
67 views

Gdal: highest and lowest point/pixel, how to get their altitudes?

Given a .tiff topographic raster image. How to get the altitudes of the highest and lowest point/pixel ?
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349 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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39 views

How to extract raster using corresponding polygon using ArcPy?

I have to perform a simple raster extraction, but I can't find the way to do it. In a polygon layer, I have watersheds with their ID's. And in a folder, I have rasters, each one corresponding to a ...
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40 views

How to combine Boolean and Fuzzy logic?

So I have a set of 5 Fuzzy Memberships and a polygon feature class, to which I already added a yes/no field. For the final map, I need to combine/overlay all Fuzzy Memberships and the rasterized ...
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3answers
114 views

Apply rotation before FeatureToRaster_conversion

I am converting polygon shapefiles to rasters. With arcpy I am using the function FeatureToRaster_conversion. gp.FeatureToRaster_conversion(InFeatures, InField, OutRaster, InCellSize) This function ...
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1answer
40 views

Extract/Split raster dataset by attribute (OBJECTID)

I have a raster dataset with an attribute table generated from a series of image classification (unsupervised) and processing tools (majority filter + boundary clean). The attribute table shows pixels ...
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1answer
74 views

Counting raster points within boundaries in another layer?

I know this question is similar to some out there, but I have tried all the 'solutions' and none of them are working for me. I am using the latest version of Qgis. I have a raster layer with ...
2
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1answer
149 views

Raster map in different zone () than region ()

I am new to QGIS (just installed QGIS 2.0.1) and am having problems running any spatial analysis tools. I followed the instructions on how to call GRASS tools into QGIS, but when I try to run the ...
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4answers
120 views

Combine overlapping rasters with priority to values of specific rasters?

I have 5 rasters that cover a large area. I want to combine all 5 into 1 raster. Each raster has data for portions of the total area that none of the other rasters cover. Raster C overlaps A,B and D. ...
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81 views

White lines in merged GeoTIFF files after ImageMosaicing on GeoServer

I have merged 21 GeoTIFF images using GDAL utilities. Each image is the result of merging 500 smaller tiles. I am using ImageMosaic in Geoserver but I am getting a mosaic that contains white lines and ...
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7 views

Printing a label from a point layer attribute on a raster layer (GRASS)

I am interpolating with boundaries using v.surf.idc in GRASS. It works wonderfully and I fully recommend it. I am creating an animation and I use v.surf.idc to generate sequential interpolated raster ...
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1answer
69 views

How can I rasterize individual features in a shapefile?

I have a large number of polygons that are overlapping. I'd like to create a heat map and plan on using raster calculation to do this. My plan: to give each polygon a raster value of 1, and adding ...
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2answers
94 views

How to extract X Y coordinates and RGB from pixels using python in QGIS?

I'm trying to white a Python plugin in QGIS (2.2) to get, for each pixel of a raster image, its X Y coordinates, as well as, its RGB (3 bands) values. At first I opened the raster file using: rlayer ...
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16 views

How to modify extent (layer) for Fuzzy Membership analysis?

When applying the Fuzzy Membership, how do I modify the extent (layer) to which it is applied? I don't mean showing the extent, but changing the values (mid point & spread) to a different layer? ...
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240 views

GDAL/proj4 equirectangular projection coordinate system units assumed by OGRSpatialReference and GDALDataset::GetGeoTransform()?

How do I configure my OGRSpatialReference object to specify an equirectangular projection system http://en.wikipedia.org/wiki/Equirectangular_projection where the affine geo-transform matrix (provided ...
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24 views

How can I remove dipoles from rasterlayer in QGIS 2.2?

I work with geomagnetic survey data. When convertet into a rasterlayer, every object with a high magnetic potential (for exampel an iron-nail on the surface) is shown as very sharp anomalie called ...
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46 views

R raster Package Moran's I interpretation

I am using raster package to calculate the local Moran's I . The example gives the range of Moran's I between - 1 to 2.47. On my own data I have see the value range -3.070423 - 7.228558 How can ...
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29 views

How do you assign classes to percentage data in a data layer?

As a learning project I need to coneptualize a GIS output for assigning classes to data in a raster layer. In this case i have the unemployment rates for relevant magisterial districts in my ...
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1answer
453 views

Problem in importing raster data from PostGIS to Geoserver

I am using Opengeo Suite 3.0.2, PostGIS 2.0.3 and PostgreSQl 9.2. I am trying to import raster data from PostGIS to Geoserver but facing an error. I follow this tutorial link to import the raster ...
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738 views

How to “clean” and vectorize a raster map?

I'd like to make use of a geological map as shown in the example below, which is only a pretty small and downsized part of the map, so editing/redrawing doesn't seem to make sense in the end. My idea ...
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1answer
348 views

ArcMap 10.1 - Tabulate Area tool “doubling up” for Overlapping Buffer Zones

This question is related to a previous question I asked: Raster Version of Spatial Join (one to many) I used the Tabulate Area tool to crosstabulate values between an overlapping "buffrast" raster ...
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51 views

Mask image based on no-data pixels in another image with different projection - GDAL or Python

I've got a land cover image which covers the whole globe, and a satellite image which covers a very small part of the globe. These two images have different projections, co-ordinate systems and pixel ...
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37 views

Zonal Statistics Freezing QGIS 2.2

Running on Windows; 8gb memory, 500gb HD, i5 cpu; Raster file: 250mb I am having a problem with zonal statistics advancing past 17%. I am trying to run statistics on a crop grown in certain counties. ...
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847 views

GDAL_translate: converting ESRI GRID to Geotiff in batch

The Challenge: To batch convert 1000 rasters in ESRI Grid binary to Geotiff using either using a batch file or Python 2.7 without ArcGIS/Arcpy module. The Tools: Win7Pro, GDAL 1.9.2 (via OSGeo4W), ...
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37 views

I had an error in Gdalwarp and i don't know the reason

I was trying to warp a raster using a mask and shift it before clipping but when i exectute the command bellow in Qgis/PyQt using QProcess: gdalwarp -s_srs "+proj=merc +a=6378137 +b=6356752 ...
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15 views

Add a raster specifying the projection in pyqgis

I would like add an raster but I want to specify the projection. If I do : qgis.utils.iface.addRasterLayer(url,layerName) QGIS ask me to specify the projection. I want to this with python. How I ...
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72 views

Workflow with raster in Qgis 2.2

I'm trying to build a workflow with the Qgis 2.2 processing toolbox. I want to clip a raster layer with a vector layer using the GDAL tool "clip with a layer mask". But it doesn't work. The error ...