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

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After turning census block data into a raster, how do I redistribute the density to reflect land cover types

I plan on rasterizing (terminology?) census block data relating to density to a regular 30 m by 30 m grid for use with NLCD data. I then hope to distribute the density of the original census block ...
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105 views

Using Zonal Statistics As Table for overlapping polygons in ArcPy?

I'm using ArcGIS 10.2 for Desktop and would like to calculate the population within a specific distance from bus stops. My input layers are: census block (polygon) with population undissolved bus ...
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52 views

Calculate area of a raster for an irregular polygon in PostGIS

I have a number of polygons with irregular shapes (i.e. non-rectangular) and want to calculate their areas after I have converted them to rasters. Here are my steps: Convert my geometry to a ...
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76 views

QGIS from console: raster algebra

I'm newbie to programming in pyqgis. I need to perform a simple "GeoTiff * A" type of calculation(where A is a constant), but I am struggling to do so. I tried ...
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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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51 views

Re-sample raster to acre grid using ArcGIS Desktop or R?

I have a 1m classified landcover raster layer that consists of values 1-4 representing various land covers. I need to resample this layer to an acre grid. Each acre in the resultant grid should ...
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51 views

plot 3D graph based on raster pixel values

I am new to raster data. I have a raster tif file with population density value in each grid cell. I am interested in plotting a 3D graph based on raster values in ArcGIS or R. The similar graph is ...
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59 views

Why are there strange horizontal lines in raster data?

I have a feature class (stored in a file geodatabase) containing information on land use for the Amazon rainforest. It is very detailed and looks like this I need to convert this shapefile to a ...
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38 views

Create a raster with fixed 10meter pixel scale in PostGIS

I have a series of points that I would like to convert to a raster, and then calculate the area of the raster as a proxy for "amount of area covered". I'm trying to do this using PostGIS rather than ...
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71 views

A raster map without a legend?

I simply download a map from here http://neo.sci.gsfc.nasa.gov/view.php?datasetId=MCD12C1_T1. this map is a tiff file. mapd <- raster("C:\\MCD12C1_T1_2011-01-01_rgb_1440x720.TIFF") plot(mapd) ...
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Trouble calculating bounds for TMS raster image tile layer

I am using TMS tiles created from a flat image. Originally the export tool created a sample openlayers file that works correctly. The top level tile folders are labelled 0-5. I've renamed these to 2-7 ...
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27 views

Splitting Raster in ArcGIS

I have a 30m raster dataset for the continental US, and would like to divide it into manageable chunks to convert it to vector, etc. What's the best way to accomplish this? I don't want any overlap ...
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34 views

QGIS raster calculator wrong output

I am trying to create a mask from a DEM (SRTM tile) using raster calculator in QGIS. I have performed the same operation in ver 2.6 with no problem but in the current version the output is incorrect. ...
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33 views

Raster displaying in ArcGIS

Can anyone please explain this to me? I need the image to be displayed right in any case as I will be using it in different programs. When I open this raster image in an existing ArcGIS map it ...
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84 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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1answer
79 views

ERROR 999999: Error executing function - Failed to execute (CopyRaster)

ERROR 999999: Error executing function Unexpected operation No spatial reference exists This is a fragment from my log report: ERROR 999999: Error executing function. Database user ...
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59 views

Georeferencing raster imagery using UTM eastings and northings

I have a scanned cadastral map in raster form and UTM co-ordinates in northings and eastings for that area. Is there any way that I can directly georeference my map using E/N values without converting ...
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50 views

Output from arcpy clip management too big

I'm using the function arcpy.Clip_management to clip a raster using the shape from a polygon. The problem is the size of the output is too big. What can I do? Here is my script (in arcmap python ...
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33 views

Is it possible to overlay ungeoreferenced raster images in the QGIS Desktop Browser?

Afternoon ladies and gentleman, I work for a company that produces Mining Investigation reports for property in the South West of England and I have spent the last 12 months digitising abandoned ...
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55 views

Not able to load any Raster File using QGIS Python

I am trying to run an elementary piece of Python code, that simply loads a dem file as a raster accessing the QGIS Python API. On the embedded console (within the QGIS application GUI), it runs fine ...
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43 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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59 views

Convert tif raster format to jpg format

Continusly to Convert jpg raster format to tif format, i try to convert tif file to jpg: import arcpy, os , glob outworkspace = r"C:\Project\out\OtherFormat" listOfFiles = glob.glob( ...
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Overlaying Shapefile with projection and raster (without projection but with defined extent) using QGIS?

I'm trying to overlay a shape file into a raster. The raster has no defined projection but it's a global raster with extent 0, -1800 : 3600, 0. I tried "on the fly CRS" transformation and followed the ...
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28 views

Cost Distance for urban and roads?

I've been working in GIS for years but I haven't done much raster analysis until recently. I need to create a cost distance for an urban area for a land capability map, and also one for roads ...
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104 views

Create web map tiles from large images

I have 70Gb of raster data from drone photography that I need to serve via Openlayers. The data is currently provided as georeferenced jpegs each is 175Mgb in size. What is the best strategy to cut ...
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42 views

raster topo map with gaps to DEM

I'm trying to create a DEM from this raster map: I managed to clean all the shapes and text. I tried to write a program which finds the curve pieces and connects them. But, I realized that it is ...
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42 views

Iterating through a point layer to create & sum distance rasters

I'm writing an Arcpy program to process data in a layer of several hundred points ('ptsLyr', from file 'ptsFile'), each of which has its own ID ('RecordID') and an associated value, 'radius', that I ...
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44 views

Proof low deviations in DEM compared to point dataset

I am not sure how to achieve the following consistently: I have a regular distributed point dataset (surface elevations). From this I derived several DEM using QGIS IDW Interpolation method. Now I ...
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46 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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44 views

can i comparing landsat 7 and landsat 8 thermal band?

can i comparing landsat 7 (band 6) and landsat 8 (band 10&11) thermal band? because landsat 8 only have 100m spatial resolution, so the output looks more general or blurr than landsat 7 thermal ...
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39 views

How to extract values from raster at points with many different rasters and points

I have a folder containing 100 DEM rasters. I have a point file containing thousands of points. I need to collect raster values at all of these points. Only some of the rasters intersect with the ...
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Plotting Netcdf data. How to get right projection?

Maybe it's very easy for someone to fix, but I'a a new one in R, so I really need help. I/m trying to plot data containing lat, lon and variable (nmf2). The grid isn't a regular one, so there are some ...
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56 views

Explaining ArcGIS Raster to Polygon output?

I want create a new shapefile with selected fields found in a raster which depicts landcover. I first attempted to run Raster To Polygon. However, some class names no longer appear, as shown here: ...
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29 views

Adding polygon attribute to a gdb raster

I am working with the gSSURGO soil database which has many tables with data and one raster file. I managed to join the tables to the raster, so now I click on my map and can see all raster attributes. ...
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27 views

Get Raster Values from a Polygon Overlay in ArcGIS

I have the same problem as Curlew in Get Raster Values from a Polygon Overlay in Opensource GIS Solutions and thecrashlandingdodo in Step-by-step: How do I extract Raster values from Polygon overlay ...
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91 views

Converting DEM to Floating Point Raster (FLT) using QGIS?

I am looking to convert a .DEM exported from AutoCad to a floating point raster file type (.FLT) utilizing QGIS to implement in HEC-RAS Mapper. This is accomplished easily in Arc using the ...
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20 views

Pixel based transparency or “Lighten” on geoserver

This is similar but different from this question. I'd like to statically assign a transparency of one raster based on another raster. For example, say I had a raster of aspect in a spectral gradient ...
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1answer
100 views

How to make maps out of imagery?

I am working for a client and we chose to use OpenGeoSuite as our system. Our client will be flying a plane over farm land capturing images that we need to put in our system. From my understanding ...
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Add QGIS raster layer to Google Maps API

Is it possible to add a hosted QGIS Raster layer into a Google Map? Thanks.
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25 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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2answers
56 views

Extract from raster by tightest rectangle mask without Nodata

I'm using ArcMap 10.2.2 and I have a raster that has Nodata around the edges. How can I extract the tightest rectangle from this raster that does not include Nodata? The screenshot may help ...
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45 views

chi-squared for two rasters in R

I am kind of new with statistics. I have two raster with categorical values and I want to get chi-square. How can I do this using R? Rasters have the same region and same resolution. Is chi-square ...
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Automate Exporting of Rasters Using Renderer in ArcGIS

It is possible to export rasters in ArcMap by right clicking the layer-> Data-> Export: You can then click 'Use Renderer' check box to ensure the image you export uses the current ...
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31 views

Euclidean Distance with Weighted Values

I am currently dealing with a dataset which consists of about 2700 points stochastically placed in a study area of about 650,000 sqKm. I am trying to create a distance raster for these points, which I ...
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59 views

Problem to visualize raster data from PostGIS in QGIS

I have two multiband raster files and i'm trying to load these data into PostGIS using raster2pgsql. Here is the syntax that i used: raster2pgsql -c -s 4326 -I -t 100x100 *.tif ...
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22 views

Merging rasters in Openlayers

I'm using Openlayers 2.13 and GeoServer 2.5.2 and I want to merge rasters. After short searching on Internet, I haven't proper, not even close, solution for this. How can i handle this? Thanks in ...
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44 views

Using Polyline to Raster tool in ArcGIS

Pretty basic question; In this Polyline to Raster tool, there is a field called "Value Field" I am not sure what to put for this field. My polylines are ZM, so there is Z information for the line, I ...
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23 views

Clipping a Raster into 5x5(25) equal tiles through the use of arcpy?

I am curious to find our if there is a way to create a python code that enables you to clip a raster into equal parts example: 5x5(25) tiles with the use of arcpy? From what I can think of you would ...
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59 views

Where do I get Elevation Data for Scotland?

So I am new here and I arrived here because I have been searching for quality elevation data for the entire Scotland but I have not succeeded yet. Kindly help if you know where to get the data Raster ...
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1answer
39 views

QGIS raster from interpolation not scaled correctly

I am using the interpolation plugin in QGIS to interpolate values within a boundary. I start with two layers; 1) my points and 2) a polygon for the area of interest. Then I go to ...