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

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Counting NoData values in raster using ArcGIS Desktop?

I have created a raster in ArcGIS Desktop 10 with a large number of holes (NoData) in it. I want to fill the holes using something like the the following: rOut = ...
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Calculating Net Primary Production (NPP)?

When I calculate Net primary production (NPP) for a local scale, what kind of software should I use? I always use ENVI, ERDAS IMAGINE, ArcGIS for Desktop and IDRISI. Is it possible to use these ...
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802 views

Combining two overlapping rasters (combine cells, retain both values) using ArcGIS for Desktop?

Using ArcGIS 10.2, I am trying to combine two rasters which are identically overlapping in shape and extent, but with different values and counts. As an end result I would like each cell to retain ...
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112 views

How to digitize RGB TIFF automatically

Is it possible to digitize RGB TIFF by color - I need to select all the vegetation cover types from the image below, which is a part of an aerial photography of an island ...
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264 views

Problem loading output layer QGIS

Every time I run operations with temporary file output from the graphical modeler, I get the following error message: Oooops! The following output layers could not be open CLIP: ...
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222 views

How to convert float to raster in QGIS

I have downloaded bathymetric data into QGIS. In order to use it I need to conduct a float to raster conversion. I have not been able to find how to do this on any of the forums. I have unsuccessfully ...
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84 views

Error on 'Extract raster values to CSV' in batch process in QGIS

The Extract values (csv) contained a bug in the script. The below link shows how to correct the bug. Error on 'Extract raster values (CSV)' - Error executing algorithm 1 'Dataset' ...
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2answers
247 views

Resolution difficulties in Grass

I have gone through similar questions to mine here, but I didn't find a solution. Please help! When cropping a raster image by using g.region & r.mapcalc, I get a new image but the resulting ...
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201 views

Why covariance values are different in R and ArcGIS?

I've calculated covariance between 7 rasters using R and ArcGIS. It gives me different results. Each times covariance values from R are approximately 1.874 times higher than ArcGIS values. R - ...
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56 views

What kind of methods are most commonly used to interpolate a relief?

I have got a topographic plan with height measurements which I converted to point shape file with height value in attributes. I was wondering, what kind of methods are most commonly used to ...
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394 views

How can I transform raster to vector in ArcGIS?

I want to convert from raster data to vector dataset using ArcGIS. Raster data consists of pixels and center of z values. Vector data sets consist of points, lines and polygons and x,y values. When I ...
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62 views

European road usage statistics per highway

I'm looking for an open data source which features the amount of cars per road per day or per year for Europe(!). I've found several national reports, which are only available as PDF and as such a not ...
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895 views

How to extract pixel value counts from a raster in QGIS?

How does one go about obtaining a summary of the counts of cell values within a raster in QGIS? I know QGIS is doing this, in order to provide the summary statistics and histogram in the properties of ...
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87 views

Error on 'Extract raster values (CSV)' - Error executing algorithm 1 'Dataset' object has no attribute 'mapToPixel' See log for more details

I would like to extract raster values at some locations (point shapefile) in 'csv' format. I use 'Point Sampling Tool' and it works well for a raster file. However, I have hundred of raster files ...
2
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1answer
136 views

How to create header files for multiple rasters in R

I have nearly 1000 generic binary images, i.e., headerless, band sequential and binary (16-bit signed integer). I have been succesfully able to load these with package 'raster' only when I create an ...
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1answer
209 views

Progress bar percentage is increasing and decreasing, never finishing

I am trying to clip a raster by shapefile perimeter using the Clip tool. The percentage has been jumping between 0% and 100% for over an hour, back and forth, climbing to 100% then dropping down to ...
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571 views

Creating field with specified slope projecting from 3D polygon?

I am trying to figure out how to create a elevation raster from a known location (3D polygon) that projects at a specified slope (1%) for a specified distance(1-2 km). Does anyone have any idea how ...
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1answer
207 views

Adding a grid and selecting random cells from spatial polygon in r

I have a fairly similar question to this: Similar Question I am working with a map of Denmark or more a subset of a Denmark Map. This file comes from the Global administrative areas site GADM site ...
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2answers
44 views

Get raster expression

In Arcmap I have made a new raster with ArcToolBox -> Spatial Analyst Tools -> Map Algebra -> raster calculator. Now, months later, I have forgotten the source formula expression. How can I ...
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53 views

Combining raster images? [closed]

I've decided to work on GIS implementation in transportation. I've these small tiles of images, with world files. I want to combine them to create a base map. I don't know coding/programming, so ...
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2answers
418 views

Cropping or removing borders (not NoData) from multiple scanned and georeferenced maps (ArcMap or QGIS)

I have several hundred scanned maps in TIFF format, each correctly georeferenced and forming a large grid of images. The problem is that the border for each map is present - a white band, with a black ...
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1answer
659 views

Problem about converting raster to polyline and calculating total length

I have raster file of line segment. I need to convert it to line and get the distance of that line. How can i do using Python and ArcGIS 10? I have tried with GIS tools Convert Raster to Polyline but ...
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469 views

How to create the attribute table for a raster that was produced by the Slope Tool (ArcGIS10)?

I use the Slope Tool (Spatial Analyst Tool – Surface) of ArcGIS10 by ASTER GDEM (that was exported to UTM projection). The program produce new raster (with slope value), but the resulting raster ...
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74 views

Converting rasters to polygons through cell centers

With arcgis, it is possible to convert a raster image to a polygon representing the boundary of the raster using the Raster To Polygon tool. The output polygon will follow the cell edges of the ...
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126 views

Export raster from QGIS 2.4 to PostGIS

How can I export a raster file out of QGIS (version 2.4) into a PostGIS database? I am looking for a module or python script.
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55 views

DEM error when trying to do topographic correction in GRASS

I'm new to GRASS gis and I'm trying to do a topographic correction (i.topo.corr) of 9 ASTER bands using SRTM dem. I keep getting this error message: ERROR: Illumination model is of CELL type Is ...
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183 views

How to correctly render a raster Layer to GTiFF with QGIS python console?

I am trying to render a map from a raster layer. As recommended in pyqgis cookbook and here(osgeo.org) I use QgsMapRenderer(). I am able to produce a picture but it has not appropriate extent and ...
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113 views

Changing extent on a raster in QGIS

I rasterized a shape. The resulting raster (lets call it raster 1) has a different extent. I made a virtual raster with the original polygon and I tried to multiply the virtual raster with raster 1 ...
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1answer
203 views

QGIS Scripting problem updating contrast enhancements for raster layers using bandStatistics

Found this function to update statistics for a raster layer : rlayer.setContrastEnhancement(QgsContrastEnhancement.StretchToMinimumMaximum, ...
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1answer
96 views

Underwater terrain modeling

My task is to model the surface of a lake bed, calculate volume of it and visualize it as 3D a surface. I have acquired depth measurements in a small lake using echosounder. The precision should be ...
5
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1answer
496 views

Convert ESRI Shapefile to Raster using R - biggest polygon area to raster cell value?

I want to create a raster from an ESRI shapefile. Multiple polygons may exist in one raster cell. If so, I want to assign the attribute variable which occupies the biggest area of the raster cell. ...
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2answers
76 views

How to get for a given pixel the values from different overlapped rasters?

I have a few rasters representing different soil properties, like soil pH and sand content. The rasters overlap perfectly, have the same dimensions and same coordinate reference system. I would like ...
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185 views

Create Georeferenced Raster For JPEG file with Mapnik Python

I am able to use Mapnik generate_image.py to generate image with a BBOX and projection. Also, I have added a python script to generate a JGW file. But to completely georeference the generated image. ...
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138 views

How can you create a depth raster from a DTM and a polygon in QGIS?

I have a DTM raster and a flood outline in polygon format - how do I create a depth raster for the flood outline (i.e. flood level minus DTM level)?
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How I can create a raster and have the same overlay as another raster in QGIS 2.4?

I have made a graphical model in QGIS 2.4. I have to create a raster equation to rasterize a polygon shapefile. I want to rasterize my shapefile and I want to ensure that this new raster will ...
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4answers
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Find the best path along raster

I've just posted a question to StackOverflow about the best way to go about finding the best path on the raster below (where whiter pixels are 'better'), but have realised that it might actually be ...
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1answer
190 views

How to calculate area of respective pixel?

I wants to create NDVI Map, In which it shows an area of respected pixel value lies in map.I have NDVI value within -0.6 to 0.7. Suppose,I wants to calculate area of 0.5 NDVI value with scale of ...
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1answer
269 views

Tabulate Area for large datasets

I have been struggling trying to use Tabulate Area in Arc 9.3 for a large raster dataset. I have one raster with 8 land uses and another vector layer with zones (which I converted to a raster with ...
2
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1answer
641 views

How do I pass each parsed file name to the next tool in Model Builder? [duplicate]

I cannot get the Parse Path tool to pass each file name to the next tool. In the example shown, the Raster to Ascii tool will take the first entry in the 'filename' variable list as part of the output ...
2
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1answer
116 views

Map algebra for loop

I have never coded in Python before and I am trying to loop a simple map algebra equation across 365 rasters. I am trying to calculate total water flow over cells but in the raster I have a negative ...
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51 views

ArcGIS Viewshed's show no visibility to south east

I'm using ArcGIS 10.2.2. I've been running some viewsheds using DTM files from EDINA Digimap and data that I've imported using .csv files. These files only contain the X Y details and a code for each ...
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1answer
667 views

How to create a catchment from a point using a DTM raster in QGIS?

I need to find a better way to delineate a catchment from a given point on a watercourse using a DTM - currently I am either using FEH, or if the catchment is too small using contours to draw ...
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1answer
538 views

How to bring georeferenced raster data into MAPublisher?

What is the appropriate method to import a georeferenced raster image into MAPublisher? I have been able to import other forms of map data, and created map views and such for them, but I am now ...
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83 views

Different ST_AZIMUTH results for ST_PROJECT points along the same original bearing

I'm trying to develop some way of determining line of sight (LOS) between two geographical points about 1km apart or less using ST_3DINTERSECTS or something similar. BASIC PROBLEM: Along the way, ...
4
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1answer
213 views

Example of a “bleeding” raster in GIS?

I was reading an ArcGIS Help page recently on Polygon to Raster (Conversion) GP tool. There is piece of information there that I became interested in: If "bleeding" or stripes occur in the output ...
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1answer
350 views

Random-Forest Classification of 10cm Imagery for species-distribution in R (no point-shapes)

I'm actually trying to classify 10cm-resolution images with the RF-package. I do this to separate some species in the forest, seen on my images. While I was searching for an answer, I found the ...
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Create Raster file in R from Matrix and latlons

I could use some advice on how to create a Raster file in R with a Matrix of data points and the coordinates stored in a separate file. Both, data and coordinates come from a NetCDF file. I extracted ...
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2answers
121 views

Batch Conditional Test - For Loop with a Group of Rasters

Edit: Question was answered. Please scroll to see fixed script. Thank you everyone who helped! How do I ask a “for loop” to operate on groups of three files folder (e.x. files A, B, C), then files ...
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1answer
45 views

Finding DEM/HIllshade sources California

Creating watershed maps for schools. I want to color ramp the elevation to show low and high points. What kind of files do I need and where to find them?
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2answers
895 views

Conditional combining of multiple rasters to produce one output using Python?

I have two rasters for same spatial extent and need to compare both rasters cell by cell and produce one output raster. Each has 10 land cover classes. Based on those 10 classes the comparison should ...