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

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QGIS clipper problem when mask used

I have encountered a problem with the raster>extraction>clipper function in QGIS when a mask layer is used. In the image below the diagram on the left shows part of the original raster. The diagram ...
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18 views

QGIS: Delete information from rasters and shapes that are out of country borders [duplicate]

I am trying to make topographic maps for some countries and show only those countries. I already created reliefs from SRTM-data and imported lake and river data from Natural Earth. Now I want to ...
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10 views

Panel plotting of raster images

I have never used panel plotting for raster images in TIFF format. Any ideas what would be a better module/library to panel plot raster images with examples?
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22 views

Combine multiple binary rasters to a single raster

I have 5 different species richness maps which I am trying to join in order to show one cohesive map. Each species raster layer has values of 1 and 0; 1 if the species lives there and 0 if the species ...
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26 views

Rasterize gives weird image

ro<-readShapeSpatial("roads") ra<-readShapeSpatial("railways") co<-readShapeSpatial("LIE_adm0") u<-union(union(extent(ro),extent(ra)),extent(co)) rast<-raster(u,res=1) ...
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Landsat Data to Map Slums in India

I am working on a project to answer the following geographic question: How much have slum areas increased in Mumbai, India, since the 1970's (or earliest data). I have downloaded LandSat imagery and ...
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1answer
27 views

Determine value nearest to given coordinates

I'm new to GIS and have a very simple question. I have a raster that specifies the geographical distribution of temperature. I would like to find the temperature that is closest to a particular set of ...
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1answer
20 views

Mosaic to new raster: same number of bands issue

I am trying to mosaic 32 raster files (min value 0, max value 13) into one raster file so that I can later use this new raster to extract multiple values to points. However, when I try and mosaic the ...
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2answers
28 views

QGIS error when importing .asc LIDAR data

First let me say that I am novice in GIS department. As archaeologist I had only some courses 8 years back when i was still studying. Now, the problem: When I try to import .asc as raster layer I ...
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29 views

Can the maximum and minimum values of raster display be changed automatically when changing the data frame extents?

I have a raster layer in arcgis which covers a large surface area. I would like to be able to zoom into specific areas of this raster and have it display only the range of values in the area I have ...
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30 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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35 views

creating a random gdal raster with random predefined values

So far I have developed the below code but for some reason it only works for say one class of landuse instead of two. Would you please tell me where I have gone wrong? Thanks so much import os, ...
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23 views

Clipping rasters

We are clipping one raster to another and our teacher gave us this hint for the 2nd parameter "Remember that the Describe function returns an object. The Clip tool will need the string representation ...
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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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36 views

Term for combined Raster and Vector data [on hold]

Is there a GIS term for a single feature that contains both Raster and Vector data? IE: A topographic shaded relief raster that also contains the vector elevation data? I am working with GRID data ...
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14 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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1answer
16 views

Querying Raster Dataset by Location to Study Area

I have downloaded a very handy raster dataset generated by the Nature Conservancy for identifying terrestrial habitat cover types in the north east. Link to the project info and a link containing a ...
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46 views

How to compute layer by layer after stack?

I have some rasters that I want to compute the moving average and then rewrite the rasters again. r1 <- r2 <- r3 <- r4 <- r5 <- r6 <- raster(nrows=10, ncols=10); r1 <- ...
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multiply a rang of values in a floating raster to a constant

I have a floating raster layer. I want to multiply a rang of its values to a constant. So, I used the "Con" tool in map algebra with the following script. Con(("Extract_rast1" >= 0) & ...
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How to re-grid a raster using area-overlap weighted averaging?

I have two rasters r and r2 with different resolutions. I want to re-sample (re-grid) r2 to be the same as r using area-overlap weighted averaging:If an r grid cell is covered by more than 1 ...
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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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29 views

Importing raster from ArcMap to Adobe?

I am currently working with 3 data frames in ArcMap. I exported them to pdf then Adobe Illustrator. I noticed that 2 of the data frames that include rasters come up with striped layers on them (while ...
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41 views

Extract values from raster by using polygons

I am working with multiple raster files that cover all of united states. The file format of the rasters - GeoTIFF. I have around 100 geotiffs that I need to process. Then I have another shapefile with ...
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30 views

Clipping raster out of polygon using ArcGIS Desktop?

I'm kind of a noob to the GIS programs, and I'm trying to create a map in ArcMap 10. I have a polygon which I manually created in Google Earth and then imported to ArcMap with the KML-Layer tool). I ...
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22 views

How to add a plot with a different x axis to an existing plot?

I am plotting a raster but I want combine to things in the same plot but in two different axis. library (raster) r <- raster(nrows=10, ncols=10);r <- setValues(r, 1:ncell(r)) extent(r) = ...
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Questions on raster math using ArcObjects

BACKGROUND INFORMATION: I'm using the 10.2 .NET API and what we are doing is this: I have a boat moving on the water at a cruising speed of 30 nm/hr. (and we don't care about currents affecting the ...
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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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9 views

merge rasters using mosaic to new raster - wrong output

I am attempting to merge two raster datasets into one output dataset. I am using the Mosaic to New Raster tool. Unfortunately, the output does not display the same categories as the original input ...
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33 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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24 views

Kernel density raster - convert to real world values? [closed]

I know there have been a few posts on this topic, but I am still struggling to find a solution. I have point data representing the number of samples in a location and have created a kernel density ...
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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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3answers
34 views

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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23 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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51 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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16 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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47 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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28 views

Issues with making a seamless raster layer [on hold]

I am trying to create a seamless raster of SRTM data for Africa from numerous SRTM layers that I have mosaicked together. However, after this processed for 12 hours, this has been the output ...
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1answer
44 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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1answer
52 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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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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28 views

Projection conversion from UTM to Lambert Conformal Conic displacement issue [closed]

I have a raster image with following projection characteristics: NAD_1983_UTM_Zone_19N WKID: 26919 Authority: EPSG Projection: Transverse_Mercator false_easting: 500000.0 false_northing: 0.0 ...
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1answer
34 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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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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2answers
47 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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16 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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85 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 ...