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

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How to calculate zonal statistics from multi-band raster for each polygon using python?

I want to calculate the zonal statastics from multi band raster for a polygon layer. When I am using this snippet of code: vectorlayer=qgis.utils.iface.mapCanvas().layer(0) rasterfile = ...
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60 views

Geoserver renders reprojected raster only as transparent images

Trying to reproject WMS layers in geoserver from the default of EPSG:4326 to EPSG:3574 Using the default projection works fine. url = ...
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16 views

Sampling raster by line in QGIS

I am quite new to GIS, and was wondering if you might be able to help me out? I have a raster layer for gradient as well as a line created from GPS tracking points(using the point connector tool). Is ...
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24 views

Spatial segregation from a raster of racial distribution in the USA

I am trying to measure the degree of racial segregation at some geographic level (let's say the county level, for simplicity) in the USA. I have a shapefile with these geographic units. To do so, ...
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1answer
34 views

Importing TIF raster in QGIS, default color band

Where can I change the default color bands for importing raster images? When I import a TIF image the green color band is not set causing a purplish image. When I set it in the properties it views ...
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45 views

Why do my raster pixels not align?

I am working in ArcMap 10.2.2. I am trying to project a NED 3m dataset from a Geographic Coordinate System to a Projected Coordinate System. The output rasters pixels do not overlap the original ...
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33 views

Assigning Raster Cell data to Point data

I have 23 sets of raster data for different types of habitat (which I have performed Block Statistics on in Arc10.2, in order to create a 1km grid). I also have 5 different Sets of point data showing ...
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42 views

How to align hundreds of rasters quickly

I'm hoping to accurately align hundreds of aerial images that are slightly off-kilter. The images cover the same area on different dates (several acres). They contain identifiable features around ...
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2answers
43 views

Converting NoData to 0 values in ArcGIS Desktop?

I have a raster of landcover that I have reclassed and the different land cover classifications are now represented by numbers which correspond to fertilizer inputs. Using ArcGis 10.3, I am trying ...
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42 views

How can i import raster image to GRASS GIS without losing RGB Values?

I am using GrassGIS 6.4.2, How can I import raster data to GrassGIS without losing RGB Values? The raster image format is TIFF, the below commmand is using to import raster image: r.in.gdal ...
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124 views

Dissolving/Unifying Ill Behaved/Irregular Polygons in R

I'm working on a project involving bringing together multiple subjects circling difficult to find parts of an image. The output from users is pretty awesome. Cool, right? However, what I want is ...
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40 views

How to obtain an euclidean distance raster from a vector file in QGIS?

I'm trying to obtain a raster of Euclidean Distances from a vector layer I have of a river in Spain. I did it very easily with ArcMap using Euclidean Distance, but I don't know how to do it in QGIS. ...
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44 views

Adding pixel value data from a raster layer to a number of buffer polygons ArcGIS

I have created a layer of polygons with buffers around my points of interest, all of the same size, in Arc GIS. I also have a raster layer of nighttime lights with pixel values between 0 and 63 ...
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231 views

Create raster with grid cells values based on area covered by polygons

I have a polygon data with area covered by the forests (data is here - https://www.dropbox.com/s/zgckliydalljw6a/sp_data.zip?dl=0). I want to convert polygons to raster. The value of each grid cell ...
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1answer
95 views

Difference between gdalwarp and projectRaster

I am trying to project a Raster. In R there is the projectRaster() function to to this (below a fully reproducibly example) : # example Raster require(raster) r <- raster(xmn=-110, xmx=-90, ...
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34 views

Where can I download a raster dataset with the latitude and longitude of each pixel in geographic projection?

I want to do raster calculations in QGIS based on the latitude and longitude of each pixel. The calculations will compute the area of the pixel, but also do other calculations for various projections ...
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2answers
95 views

Clip Raster to Polygon Grid?

I have a polygon grid file and want to clip my raster imagery to the shapes outlined by it. I am using arcmap and was wondering if there was a tool directly for this? I would like to also be able to ...
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1answer
220 views

Topo To Raster executing but not creating the raster

I am using Topo to Raster by File (ArcGIS version 10.1) via arcpy on a large stream and point dataset. Arcpy runs fine and executes without issuing any error message, however it does not create the ...
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1answer
970 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
80 views

Suitable Raster processing methods to extract field boundaries from images

I'm trying to extract field boundaries and features from a lot of aerial images of agricultural land - and avoid digitizing these features manually. I've managed to get a crude raster file of the ...
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26 views

Invalid drop item: Calculate statistics

I have a number of rasters that I need to calculate histograms for. These are continuous rasters from 0 to 294.208 - many decimal places. I need to be able to classify the histogram down to at least ...
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2answers
415 views

Getting Raster exported from ArcMap into Google Earth (.kmz) with transparency preserved?

RasterLayerExportClass will only create a .png with a single value transparency, however there is a bug in Google earth which prevents this from working. The other export options don't support ...
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1answer
1k views

Problem merging two rasters in Qgis

I have two rasters in Geotiff, same CRS. I tried to merge them and I have this error code ERROR 4: `C:/Anita_Tepoztln/Rasters/e142.tif' does not exist in the file system, and is not recognised as a ...
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47 views

Extracting Data from Raster based on Aspect Raster file

I have 2 rasters, ones shows aspect and another shows date of snow thaw. I want to extract the date of snow melt based on values from the aspect raster. For example I want all the snow thaw dates from ...
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45 views

How should i combine these rasters?

I have two buffers that i want to combine. I tried overlay with fun=function(x,y){return(x*y)} but 0*5 = 0 so it produces NA's.I don't know how to combine them the one buffer should be 500 and the ...
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34 views

Cannot find information about my.table table in raster_columns

I am running PostgreSQL 9.4 and PostGIS 2.1 and have loaded a small piece USGS SRTM data for North America successfully into my database. I am attempting to export a small piece of of the rasters I ...
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56 views

Does gdal_calc only support 26 input raster files at a time?

In gdal_calc.py, input files are specified with letters A-Z. Here are two files, input.tif and input2.tif, being averaged into result.tif: gdal_calc.py -A input.tif -B input2.tif ...
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31 views

Reclass by Table giving output with only 8 catergories

I am attempting to reclass a raster from a table (using the Reclass by Table tool in Arc 10.3). The output value field I am trying to reclassify to is long integer format with values ranging from 0 ...
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17 views

What is the recommended approach to client side clipping, by geometry, of an ArcGISImageServiceLayer?

I have an existing Esri Silverlight application with an ArcGISImageServiceLayer and we need to add the ability to clip that raster, by a geometry. And ideally, do this on the client side since the end ...
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72 views

How to reclassify a raster in R?

wet<-readOGR(dsn=".",layer="shp") #wetlands r.raster <- raster() extent(r.raster) <- extent(wet) res(r.raster) <- 100 wet.r <- rasterize(wet,r.raster) #rasterize plot(wet.r) ...
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54 views

Editing .tiff rasters in Python

I am triying to edit .tif rasters in python, but I have some issues regarding the tiff to array converstion. I read there are multiple options for opening rasters (gdal, PIL, matplotlib), but which ...
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190 views

How can I create an animation with raster data in qgis?

I have 4 raster images showing different coniditions of air flow distribution at different times. I'd like to create an animation to show the change from image 1 to image 4. How can I do this? I tried ...
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1answer
586 views

Build Raster Attribute Table with GDAL Utilities

Is there a way to build a raster attribute table using one of the GDAL utilities? I know you can view it using gdalinfo and I have successfully created one using Python, but it would be so much ...
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1answer
100 views

How to round pixel values of a raster in QGIS?

I have a raster with float number values for example: 2.544459104537964 and I want to round these up to intergers. I have seen other posts on ArcGIS like this one but when I use Raster Calculator in ...
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3answers
65 views

Combining rasters to calculate total inputs

I am working on creating a map of total chemical inputs into a study area. I have several raster layers of different inputs with values stored in the attribute tables. I am having a hard time ...
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694 views

How to create a raster (topo to raster) with non-rectangular shape?

I'm using Arcmap 10, I need to create a raster from contour lines. These contour lines were clipped out with a certain shape with the purpose to modify them only within that shape and then create the ...
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1answer
81 views

Split raster into tiles

I have a raster that needs to be split into tiles (each tile a new raster). I have a Shape file with multiple polygons (these polygons are how I want the raster split). I have Gdal and QGIS. Any ...
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2answers
140 views

QGIS print composer export excludes one layer

I am trying to export a map from QGIS print composer but the resulting files (I've tried all image, .svg, and .pdf formats) do not appear as the map did in the composer. It is as if one of the raster ...
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93 views

GDAL raster shifting with python error: 'NoneType' object has no attribute 'GetGeoTransform'

I'm trying to shift a georeferenced raster by 0.5m N and 0.5m W in QGIS using the python console: from osgeo import gdal # Open in read/write mode rast_src = gdal.Open('test_raster.tif', 1) # Get ...
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1answer
105 views

How to reproject a raster from lat/lon to UTM in R?

i have to turn it into a UTM in order to make the buffer functional. wets<-readOGR(dsn=".",layer="shapefile") r.raster <- raster() extent(r.raster) <- extent(wets) res(r.raster) <- 100 ...
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1answer
39 views

how can I get the majority (dominant) class of a raster to an area (polygon) using qgis?

I have a vector layer with many basic units of planning (zones), a raster layer with three classes of geology and other raster layer of geomorphology with five classes. How can I update the ...
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39 views

Combining tiff with shapefile

I have a geotiff image with a D_WGS_1984 Datum of land cover for the continental US and I want to be able to merge it with a US counties shapefile. What is the fasters and best way to do this? My ...
2
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1answer
243 views

How to iterate GRASS region definition?

I am using GRASS r.skyview command (v.7, Windows) to determine "urban canyon effect" on pollution due to the presence of buildings. The command nicely works, unfortunately I need to process a very ...
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1answer
54 views

How to rasterize a vector dataset in R?

I would like to compare vector vs raster data. So i try to fix a problem using both ways. I made it in vector first : coastline<-readShapeSpatial("shp") wets<-readShapeSpatial("shp") ...
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54 views

Raster map source for desktop, commercial application

We develop desktop, commercial application for Architects (c++). In a future update, we would like to provide our customers with the option to automatically create a 3D terrain with appropriate ...
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2answers
50 views

How to export query result on raster table in PostGIS

I did success query on a raster table in postGIS(raster data clipped by a vector polygon), now I want to view the query result in QGIS. But how to export the query result to another table. In vector ...
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513 views

Using ArcGIS to filter cells where 7 or 8 of neighbors are different

I have land cover data that I would like to clean using some generalization tools. Majority filter does almost exactly what I want, but is missing one key option. Majority filter allows you to change ...
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3answers
46 views

Selecting parcels in vector map from raster layer using ArcGIS for Desktop?

I am relatively new to Arcgis and I am stuck. I have a parcel map (vector) and a land cover map(raster). My land cover map is only 1's and 0's, flood and no flood. I want to be able to highlight or ...
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37 views

Problem with calculating slope in QGIS

Ive downloaded DEM form earthexplorer. But after calculating slope I only have blac img. with same value in min. and max. When calculating aspect or relief, DEM works correctly. Have you met with ...
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122 views

Raster to vector (polygons) with generalisation

I have created rasters showing different types of vegetation (bushes, trees, open land) with help from lidar data. Now I'm looking for a method to turn these images into polygons. I'm using a Mac ...