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

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Counting number of Raster Cells satisfying a criteria within a Polygon

I have a USA raster dataset, which assigns to each cell a value from 0-100. I also happen to have a USA county shapefile. I simply want a count of the number of pixels/cells in the raster data with ...
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39 views

How to export georeferenced Raster layer using QGIS2Leaf Plugin?

I got excellent results while exporting vector layer with styling through qgis2leaf plugin. Whereas when I try to do the same with a geo-referenced raster file (geotiff) which has a projection of ...
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75 views

Merging rasters which overlap using ArcGIS for Desktop?

I need to merge two rasters which overlap, both indicate distance values. I need the output of the merge to result in the shorter/lower distance value. I am using ArcGIS 10.1. I hope it is more ...
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18 views

Global raster image extent

I have a global raster image that has been generated from .hdf file, referenced to world geographic coordinate WGS-1984 and it has extent as following: Top:0.5, Left:-0.5, Right:719.5, Bottom:359.5. ...
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79 views

Fixing Raster Calculator Error 000539 ImportError: No module named numpy? [duplicate]

I've created 4 hillshades for a particular area to represent the 4 seasons in a year. The equation I now need to use to determine solar insulation is 1000*hillshade/255 in raster calculator. However, ...
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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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R: How to get latitudes and longitudes from a RasterLayer?

I am an absolute beginner of geographic data, so please, forgive me if the question is not appropriate. I downloaded data from NCDC NARR and managed to load into R using the raster package. I would ...
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I am getting error in PostGIS 'function st_clip(raster, integer, geometry) does not exist'? [closed]

I have to find the count of the number of pixels in a given band of a clipped raster. For clipping, I am using ST_clip(). Through clip function raster is clipped with a polygon. I am getting ...
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60 views

How to extract values based on names of rasters?

I have a raster r that contains values for each grid cell (which vary from one cell to another). I have other 24 rasters where the names of the rasters are: the name of r1 is data-00.img, the name ...
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64 views

Calculate change in canopy height over 10 years?

I want to know how many "tall" trees (greater than 30 m) fell down between 2005 and 2015. I have LIDAR imagery from 2005 and 2015 from an area where many tall trees are known to have fallen due to ...
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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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36 views

What is a “value raster”?

I want to understand the concept of a "value raster" and if I can use it in neighbourhood statistics.
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54 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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2answers
51 views

Clipping raster python script stops abruptly?

I have created a tool in ArcGIS based on a python script that will clip a large raster dataset into smaller tiles based on a fishnet polygon feature class. The script iterates through each feature in ...
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25 views

about Orfeo tool box command line

I am trying to use otbcli_KMeansClassification command from Ubuntu terminal to classify satellite image and actually it runs without any errors but the output raster is empty "pixels without values"
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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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107 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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53 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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78 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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2answers
56 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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53 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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61 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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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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34 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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86 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
85 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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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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52 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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34 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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1answer
56 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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60 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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2answers
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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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106 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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44 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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47 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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1answer
45 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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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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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 ...