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

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creating multi band raster from one GeoTiff

I'm using AgiSoft photoscan to create a photo mosaic from aerial images. The images are being captured using a camera modified for NIR and RGB data capture. I want to be able to perform spectral ...
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What are the problems of loading overlapping (or the same) tifs into postgis?

I am still early on the Postgis learning curve. I have an existing table in Postgres - it looks like this: create table "public"."mytable" ( "rid" serial primary key, "rast" raster, "filename" ...
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180 views

Is there anywhere that I can obtain global UV data in either raster or vector format?

I'm looking for some UV data (currently with no spatial or temporal resolutions in mind, but ideally split into UV-A and UV-B) for the whole earth. Can anyone recommend a source for data like this or ...
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129 views

Black edges on overlapped raster images in QGIS

I'm beginner with QGIS and I have task currently to make some GIS map/data. I downloaded 3 satellite images from Landsat by USGS (multispectral, georeferenced) and I did overlapping of images using ...
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216 views

QGIS cannot view raster loaded to PostGIS through raster2pgsql

I tried to load a raster GeoTIFF image to a PostGIS database using "raster2pgsql" following the OpenGeo Suite Manual. The command I used is: C:\>raster2pgsql -s 4283 -I -C -M "C:\Program ...
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76 views

How to build an attribute table in a 3-band raster?

I have a 3-band (RGB) raster file from CORINE and the attribute table hasn't been built. When I try to execute the command BuildRasterAttributeTable I get an error that only single band rasters are ...
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1k views

Conditional reclassification of a raster

I am attempting to do a conditional reclassification of an NLCD land-use raster. I specifically want to reclassify all developed areas (classifications 22,23,24) that are near a road (classification ...
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53 views

Determine if shapefile and raster overlap in python

I am building a script in python using osgeo/gdal. I have a set of shapefiles and a set of GeoTiff raster files. I would like to have my script ignore shapefiles if they do not intersect with the ...
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44 views

Iterate through rasters in subfolders using Model Builder

I have a directory folder of precipitation data; within this folder are subfolders for years 1901-2014. In each of these subfolders are 12 .asc grid files; each file represents a month of the year ...
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63 views

Water feature growth

I have a water feature layer which includes rivers, lakes and streams. I want to create, essentially, a buffer of these features equal to that of a 50cm increase in elevation from its current ...
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30 views

Raster map & vector boundaryline data for Istanbul, Turkey

I'm looking where I can download background raster map for Istanbul (street map?), and then a boundary line file of the the 39 Districts in Istanbul. Does anyone have any recommendations?
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How do I display a raster “Background Value” as hollow for more than one set of RGB values?

I have two overlapping .ecw layers of the same area, though one is clipped in the middle, with a white edge. When I set the background value to 255,255,255, and define it as hollow, it only hollows ...
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249 views

Read layer symbology class color with ArcPy

I am using ArcPy within ArcGIS 10.1 and attempting to read symbology from a *.lyr file created by a raster dataset within ArcMap. My goal is to be able read out the RGB (color) values assigned to the ...
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165 views

Plot a Raster of Weather data in Leaflet JavaScript Map without generating server-side tiles?

I want to show different weather data I have as binary arrays on a server using leaflet. But I do not want to generate tiles on the server. For each point in an a array I have the coordinates in ...
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3answers
141 views

How can I determine which raster attribute covers the highest area of a polygon?

I'm relatively new to GIS and QGIS but I have a problem that I'm not certain how to solve. I searched here for relevant information but found none. (Or, I used incorrect search terms.) My problem ...
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276 views

From polygon to continuous measure of diversity?

First of all; I have tried to find a similar question, without success. Maybe it's because I'm quite new to GIS and I don't really know what exactly I'm looking for. If someone points me to a similar ...
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2answers
55 views

Gdal: clipping a raster with another raster

I'm writing a simple utility to crop batches of multi-band geotiff raster files to the same (smaller) area. Using gdalwarp, I can easily crop a file using a single-polygon clipping shapefile: ...
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56 views

How to round up/down an pixel value of a raster to a pixel value with 2 decimal places?

I have a raster (DTM) with floating points as pixel value. Now i want to round up/down the pixel values (to its next nearest value) to 2 decimal places. I use ArcGIS (with extensions) and tried the ...
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GeoTIFF world file ignored by QGIS?

I am having trouble getting geotiff rasters to get correctly placed even with a world file available. I have tracked down some discussion from 2010 that suggests that if the geotiff already has the ...
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315 views

QGis Save Raster as Rendered Image

In QGIS 1.9.0 Master, when you right click on a raster in the Layers Panel and select "Save As", you can select the output mode to be "Raw Data" or "Renedered Image". When selecting the Rendered ...
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A Distributed Cost-Distance Algorithm

I'm currently trying to implement a distributed cost-distance algorithm, however I can't seem to invent my own and still make it fast. I've been googling around a bit but haven't found anything that ...
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64 views

How to know the coordinates in a grid?

I have a raster (a catchment area) and a weather station with its coordinates (imported as .txt in ArcGIS) in UTM system. I want to know which row and column of my grid belongs to this station. How ...
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Looking for a tool like (IDW) for raster

I am looking for a tool that gives the same outputs like the IDW, but for rasters instead of points. I have a Corine land cover raster layer in ArcMap 10.2 with different friction values, displaying ...
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38 views

QGIS: raster import “nan”

I've been importing raster files in ZMAP format using QGIS 2.4 and 2.6. Some of the files work fine but other files for some reason import a black image with nan as a default black and white value. ...
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85 views

Reclassify on land cover raster won't work

I'm new to GIS so I apologize if this question is basic but I couldn't find my answer online. I'm trying to reclassify a land cover raster from the National Land Cover Database. I want to reclassify ...
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Building a Mosaic Dataset with rasters that are not georeferenced. Whats the workflow?

I have 68 aerial jpegs that I would like to use in a Mosaic Dataset. They have not been georeferenced. My question is in regards to whether I should georeference them and then rectify and save them in ...
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Map Routing (paper route) [closed]

I am doing a undergraduate GIS project. It entails a paper route for newspapers in the Pittsburgh Area, so far I have plotted all of the points in a point layer. I have now plotted my points, what ...
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31 views

Styling Raster with QGIS for publishing in Geoserver

I have a raster layer with five different landcover types denoting with 1,2,3,4 and 5. in Qgis it looks as follows: When I tried to upload this layer to geoserver using OpenGeo explorer tools, and ...
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91 views

Guidelines for publishing large datasets on QGIS Web Client

Can anybody provide simple guidance to publishing large datasets on QGIS web client? I have a mixture of shapefiles and rasters to display. Biggest shapefile is 230 MB. Biggest raster is 1.4GB. At ...
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55 views

Convert JPG image to RGB Raster to Vector Data

I am completing an analysis project for my ArcGIS class. I am analyzing the correlation between indigenous populations and food security in Guatemala. Since there is not a lot of information out ...
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38 views

How can I equalize raster?

I've got 2 rasters , its seems that 1 has the data equalized (all values from 1-65535 are there) and the 2nd don't . Is there a process I can run in order to equalize the data in the 2nd raster ? ...
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Using same line to interpolate multiple rasters, and put all profiles on same graph, using ArcGIS for Desktop?

I'm new to the website and new to ArcMap so please bear with me. I'm struggling with the "interpolate line" function on ArcMap. Long story short (hopefully): I have some bathymetry rasters of an ...
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How to check for corrupted raster data?

I am working with thousands of tiled (2km x 2km) 4-band NAIP images. When I diced the images in Erdas, the program corrupted many of the tiles. The screenshot shows an example of one of the ...
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39 views

Best way to store raster data with Java into Oracle spatial

I have a Java application that processes raster data. At the end of the process I plan to store the raster in oracle spatial. What is the best way to do this? I had a look at geotools but I did not ...
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Is there a way to export online ESRI basemap layers to raster?

I have been working on polygonizing the vegetation areas in some counties from imagery. When I have the mosaic raster locally I can easily get the polygons using Image Classification Toolbar. But when ...
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Vector to raster, then map algebra

I have a table of polygons representing travel time isochrones on particular days. For each origin point, there are five isochrone geometries (stored in separate rows). For each origin point, I want ...
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37 views

How can I shift raster layer for making cloud-shadow mask?

I want to make cloud shadow mask in QGIS. I have raster cloud mask and I have to shift it by X,Y coordinates. Is there any easy solution?
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35 views

Convert shapefile to multiple single-value TIFFs

I have a shapefile that is composed of multiple overlapping polygons that represent extent of habitats of certain species. Here is a 1 MB example of such file from International Union for the ...
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How can I identify lines that intersect a certain raster layer area?

How do I identify certain roads ( of a line shapefile) that intersect with a layer that is produced from the reclassify tool (for raster data)? I am trying to identify which roads specifically are in ...
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65 views

QGIS 2.4.0 Setting raster layer to singlebandpseudocolor using minimum and maximum raster values

I am using QGIS Chugiak 2.4.0, and I have some code in which I want to: Add raster layer to map canvas Look for the minimum and maximum raster value Apply singleband pseudocolor render type for the ...
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1answer
16 views

Converting a table to a raster for clipping

I have a series of tables (TAB files) that represent the calculated values for a corresponding .tif image. These tab files have the same number of rows and columns as pixels in the tif images. The ...
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44 views

Convert Raster into Cell by Cell Table

I'm hoping to run some Python mathematics on a raster, outside of ArcGIS. It's important to have a cell by cell table for the analysis I want to run. I plan to store it in a python dictionary similar ...
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Raster import problem

I have raster images (orthos) and feature layers in a GIS program (Global Mapper). When I import these files with the same CRS into QGIS they are literally 9000 miles apart and I cannot figure out ...
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142 views

How do I convert a .bil (and associated .clr, .blw, .hdr, and .stx) files into georeferenced rasters in R? OR to geotiffs using gdal_translate?

The title says it all. I've got a bunch of .bil files, which I can open in R using the raster command pointed to the path to the .bil file. But I don't know how to efficiently incorporate the ...
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53 views

Problem or ERROR in converting from raster to vector!

I wonder if anyone could help me out, i am kind of a beginner at QGIS. I´ve built a DEM for a project that i am developing than i´ve made the slope raster with the terrain analysis,it seemed that ...
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Conversion of Polygon vector files to Raster GRID 8 bit unsigned integer

I am trying to convert a polygon shapefile layer into Raster GRID with 8 bits and which is unsigned integer. I managed to convert the shapefile in ArcGIS with the Arc Toolbox Conversion tools, but the ...
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How to summarize canopy cover at a minimum mapping unit using ArcGIS

I am working with Landfire data and I have a project which requires that there be no area under 10% canopy cover at a 5 acre scale. I am going to use the Landfire CC2010 data and use a 5 acre moving ...
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How can one modify map service legend (specifically raster layer)?

I've got the raster layer in my map service, which in fact is created automatically by asynchronous GP service as its output result ("View results with a map service" option). The raster is symbolized ...
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46 views

Scatter plot of two rasters in arcmap for intersecting cells

How do I make a scatterplot of two rasters in arcmap which will plot the two rasters' cell values of the same cell against each other (for every cell where they intersect). I need to first create a ...
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Subtracted 2 DTM layers to find the height of trees but all we have is the pixel values, can I convert this to height?

For a piece of coursework we have an aster layer that captures the tops of trees and a panorama layer that sees ground height (both are raster) so we have subtracted one from the other to get tree ...