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

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QgsRasterLayer::identify() is missing after QGis upgrade to 2.0.1

My Ubuntu has just downloaded the latest version of QGis (1.8 -> 2.01), and my plugin failed with a plenty of bugs due to implemented changes in QGis API. I still can not figure out how do I replace ...
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41 views

What type of calculations must be done for traffic emission for buffers in land use regression?

I have a raster layer that shows traffic emission distribution by kernel density method. Traffic emission will be used as independent variable in land use regression. What type of calculations must ...
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1answer
208 views

How to change layer transparency without changing border lines?

I have a raster image of elevations. I have added a vector shapefile that contains local political divisions. I want to keep the elevation colors, but I want to keep the black lines representing the ...
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2answers
220 views

Clipping polygon layer into multiple polygons via model builder?

I have a huge polygon layer created from a raster, and over that I have a watershed shapefile. I need to run a land-use regression process on each individual watershed so I'd like to clip and export ...
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111 views

How to show cell boundaries on a raster?

I am trying to recreate a situation where each cell from a raster dataset has a black border as seen in this image. Any ideas?
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292 views

How to add raster data to Table of Contents using python?

I can easily add shapefiles to the Table of Contents in Arcmap using the following codes: mxd = arcpy.mapping.MapDocument("current") df = arcpy.mapping.ListDataFrames(mxd, "Layers")[0] path = ...
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3answers
893 views

Is it possible to open rasters as array in NumPy without using another library?

I know that it is possible to open a raster as an array in NumPy using GDAL, but I want to skip GDAL and use NumPy only, as it is cooler handling rasters with NumPy as matrices. There is a similar ...
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1answer
109 views

Load Raster Values into Shapefile [duplicate]

I have a shapefile containing many points. Some of these points fall within an area for which I have raster data. I would like to load the values of the raster which underlie each point into the ...
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1k views

Good practice for generating contours from a DEM

We have just received a large set of DEMs at work and I would like to generate contours from them. The DEMs have a resolution of 1m and a size of 1kmx1km. Output from gdalinfo: Driver: ...
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1answer
59 views

Re-sizing Raster file pixels

I have 2 JP2 aerial imagery files that are incorrectly sized. They are 100x larger than the other aerial images but correctly geo-referenced (starting x, y co-ordinates). I believe the issue is their ...
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1answer
287 views

How to get custom color palette in rasterVis plot3D in R?

I am trying to insert an RColorBrewer palette to visualize an elevation raster in R using the rasterVis function plot3D. The rasterVis reference document shows the following parameters: plot3D(x, ...
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167 views

Image classification for a study site falling over two adjacent Landsat 8 scenes (qGIS or ArcGIS)

This question concerns work-flow rather than specific methodological problems. I will be using GRASS to classify Landsat 8 images to create a vegetation map for a study site that happens to fall over ...
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117 views

Touch up tool for rasters?

I was wondering if it were at all possible to manipulate/massage rasters (eg Geotiff) using Qgis plugins or Grass?? By manipulate, I mean manually smooth off interpolation artefacts, blended surface ...
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1answer
91 views

Raster layer calculator

In PCI Geomatic, I have two raster layer.raster1 identified like %1 and raster2 like %2. if (%1 <= 10) then %2 = 60 elseif (%1 > 10 and %1 <=50) then %2=80 elseif (%1 > 50 and %1 ...
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2k views

Poor image quality of raster pyramid files in ArcGIS (no anti-aliasing)

There are several GeoTIFF files (size ~7000x7000 px) which I try to open in ArcGIS Desktop 10.0. I have already created raster pyramids for them (.ovr files) using geoprocessing tool but their quality ...
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1answer
126 views

Retrieving the proportion of specific pixel class from CHM rasters

CHM = canopy height model I am very new to R (specially for GIS purposes) and I am struggling a bit in getting the following pixel statistics: Proportion of zero value pixels = [nº of zero value ...
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1answer
1k views

ArcPy findAndReplaceWorkspacePath not working with Raster Datasets

Situation: I am working on creating a Python script that will replace workspace paths for every layer in a map document in order to fix broken layers after a data migration. The script works except ...
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1answer
215 views

“dataset does not exist or is not supported” using large GRID raster

I am trying my hand at arcpy for the first time to create a conditional raster from a set of threshold values. I have 3 large GRID format rasters (mos_zb3, mos_zb4, pca_finb2) I am trying to feed into ...
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63 views

QGIS proximity raster with extent beyond original coverage?

I need a raster coverage of distances from points outside the geographic region of interest, and am having trouble doing this with QGIS. Questions like this one (Calculating distance to points in ...
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33 views

How to combine two rasters, preferring the values of one over the other? [duplicate]

I have two rasters that I need to combine (not using the Combine tool). The values of the 1st raster are preferred to those of the 2nd raster, so I want to keep these values if they exist. Where the ...
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215 views

Saga Reclassify grid problem

I am using Qgis 2.1 ver. 5f5cd4c (64 bit version on win7 64) OSGeo installed. I was trying to reclassify a DEM in EPSG:32614. I used the SAGA's Reclassify algorithm in the processing toolbox. I ...
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46 views

Wrong pixel sums within buffers in Esri ArcGIS 10.0

I have a raster of Zambia, 100m² resolution (about 650mb). Buffers (single) at 1,2,3,4,5,10,15,20,25,30,50 km. I'm running "zonal statistics as table" in the model builder for all buffers (actually, ...
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What are Raster and Vector data in GIS and when to use?

What are raster and vector data in the GIS context? In general terms what applications, processes, or analysis are each suited for? (And not suited for!) In answering someone's question today, I ...
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1answer
204 views

netCDF-java has trouble reading this netCDF file(format) and fetching values from the latlon dimension

I'm developing an application where I need to extract variable-values from netCDF files. I'm processing several different formatted netCDF files and now one format seems to be creating some issues. ...
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1answer
257 views

How to read XY, get raster value and then update field?

I've written a script to run through a point layer, using the SearchCursor in the data access module and then read the XY values. Within the with statement, I then use GetCellValue to get the ...
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125 views

Create a band mask based on pixel locations, not in pixel values

I have this image loaded in QGIS, with two possible values for the pixels: 1 = orange, 2 = blue For simplification, assume it represents a province of a country. I want to extract just the part of ...
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25 views

Assign value to raster cells within masked area [duplicate]

The answer I previously received for this question did not solve my problem...please keep in mind that I am a GIS beginner, and it's quite likely that I carried out the proposed solution (using ...
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1answer
110 views

QGIS Grass Plugin fails with r.cost.vect

I tried the following in QGIS with the Grass Plugin: r.cost input=preCostSurface@albi start_points=OSMroads@albi output=cost0109 max_cost=0 And I get the following error: Dev note: Adapted sites ...
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3answers
2k views

How can I reclassify a raster to floating point values?

I have a raster of landuse values that I need to reclassify into pollution concentration values. I have the pollution values in a separate table. They are decimal values (ex. 0.0056), and my landuse ...
8
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1answer
2k views

GDAL RasterizeLayer Doesn't Burn All Polygons to Raster

I am trying to burn a shapefile to a raster using GDAL's RasterizeLayer. I pre-create an area of interest raster from a different shapefile, given a specific pixel size. This AOI then serves as a base ...
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1answer
292 views

Delete single raster from Raster Dataset

Is there any possibility to delete single raster previously loaded to a Raster Dataset?
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48 views

Selecting a bounded area within a raster

I am new to postgresql. I have imported a 256kb sample raster (.tiff) into postgres with tilesize 100x100. Now I need to select the area (rectangle) from the center of the image using sql query. Then ...
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1answer
70 views

How to use Plus tool in ModelBuilder?

I want to have the sum of at least 2000 raster combined to one raster layer using ModelBuilder (Plus tool). I think I'm missing something here. This model does not work.
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72 views

How to display NoData of a raster in QGIS

How can I show raster pixels with NoData value in QGIS? In ArcMap there is a button to choose the color for the NoData value. Is there something like this in QGIS?
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1answer
157 views

How to multiply raster DEM with a linear graph value

I would like to multiply my Raster DEM with a linear graph value y = mx + C. The graph values look as follows: I want to make a new raster where each cell will represent a damage factor from ...
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When a raster is clipped to a polygon with Python, why does it still take on the extent of the entire shapefile?

I am clipping a raster image to each polygon row in a shapefile in ArcMap 9.3 using the Clip tool (Data Management) in Python with Clipping Geometry set. While the clipped raster successfully depicts ...
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1answer
394 views

GetCapabilities Request for WMS

I'm trying to connect to a WebMapServer with the Geotools WMS classes. My problem is, that the resonse-object "capabilities" doesn't contain all layers. When I'm doing the request in a browser, I can ...
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1answer
169 views

Import raster into ArcGIS

I received raster data from a grid of 1100 by 1000 meters with a resolution of 1 meter. It is the output of EFC-400 software showing the field strength around power lines. The data is currently in ...
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1answer
127 views

Problem loading raster QGIS 2.0

I am very new at GIS. I am trying to load a raster so that I can complete a tutorial on georeferencing. The raster file is a jpeg. However, whenever I try to load the raster, it gives me solid colored ...
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2answers
343 views

Stripping spatial reference

I am creating an exercise for remote sensing students and would like to take an existing raster and remove the spatial reference from the file so that the students can practice using another image to ...
2
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1answer
802 views

ArcGIS - Export raster keep color scheme

I have a *.flt raster loaded in ArcMap. I would like to export this raster as a georeferenced tiff file keeping the color scheme I have provided in the symbology. I right click in TOC, Export Data ...
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26 views

calculating mean and standard deviation for raster values using whole pixels within a polygon [duplicate]

i have a raster image and a corresponding shape file. i would like to calculate the statistics of the values within polygons which have a common attribute but only using pixels which are fully ...
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2answers
177 views

How to do regression analysis out-of-memory on a set of large rasters in R?

I am trying to do a regression analysis on a set of large rasters (254,004,000 cells each). Ultimately, I want to run something like the following (or a bit more complex, but let's start simple!): ...
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1answer
132 views

Reproject gif.gz raster to WGS84 in QGIS

I am a steep learning curve into QGIS. I have a raster of global fire maps from the modis site: http://lance-modis.eosdis.nasa.gov/imagery/firemaps/firemap.2013221-2013230.8192x4096.gif.gz I would ...
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1answer
277 views

NOAA Nautical Charts .bsb format

Is it possible to load a nautical chart from NOAA into QGIS that has the .bsb format? Didn't have much luck with mrSID format. using QGIS(dev) on ubuntu 13.04
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1answer
293 views

How can I dynamically trim the informational border off of FAA sectional raster charts?

I'm trying to write a script that can automatically use GDAL to crop the informational border from the FAA's published sectional charts (GeoTIFF) found here: I know that I can use gdal_translate ...
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169 views

What causes ERROR 000732 from MosaicToNewRaster?

I'm trying to run the MosaicToNewRaster tool as part of a python script. This is my code: input_rasters = arcpy.GetParameterAsText(5), arcpy.GetParameterAsText(6), arcpy.GetParameterAsText(7), ...
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585 views

Extract Raster Values by Polyline End Points

I am looking for a way to extract elevations of end points for line data in ArcMap 10.2. I have a road dataset that I want to use as a Network Dataset in Network Analyst. I want to be able to set the ...
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149 views

filling up a depression to create new surface

A collegue here has a problem I cannot help with. She has the surface (as raster) of a landslide release area (from AFTER the slide) and wants to calculate the calculate the theoretical/approximate ...
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1answer
41 views

How to export Std Dev from Raster Dataset of DEM to classify current extent and execute Contour Tool with Python?

I want to create Countour Lines for a DEM which are based on a "STD dev" classificaion. My problem is that the "Std dev" is exported in an unknown type instead of a String. So the classifacation for ...