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

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Is it possible to overlay ungeoreferenced raster images in the QGIS Desktop Browser?

Afternoon ladies and gentleman, I work for a company that produces Mining Investigation reports for property in the South West of England and I have spent the last 12 months digitising abandoned ...
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44 views

Convert tif raster format to jpg format

Continusly to Convert jpg raster format to tif format, i try to convert tif file to jpg: import arcpy, os , glob outworkspace = r"C:\Project\out\OtherFormat" listOfFiles = glob.glob( ...
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36 views

Overlaying Shapefile with projection and raster (without projection but with defined extent) using QGIS?

I'm trying to overlay a shape file into a raster. The raster has no defined projection but it's a global raster with extent 0, -1800 : 3600, 0. I tried "on the fly CRS" transformation and followed the ...
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24 views

Cost Distance for urban and roads?

I've been working in GIS for years but I haven't done much raster analysis until recently. I need to create a cost distance for an urban area for a land capability map, and also one for roads ...
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321 views

Can ArcGIS handle missing values to create a contour map?

I am trying to create a contour map for a waterbody. It turns out that in several locations there is no data. I just don't want to use the missing values as zero in ArcGIS because it would create ...
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52 views

Problem to visualize raster data from PostGIS in QGIS

I have two multiband raster files and i'm trying to load these data into PostGIS using raster2pgsql. Here is the syntax that i used: raster2pgsql -c -s 4326 -I -t 100x100 *.tif ...
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41 views

ArcGIS Split Raster tool results in black rasters

I have a rather large raster that I am trying to split into small tiles in PNG format to upload to Autodesk Infrastructure. I came across the Split Raster tool and thought it would do exactly what I ...
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87 views

Plotting Netcdf data. How to get right projection?

Maybe it's very easy for someone to fix, but I'a a new one in R, so I really need help. I/m trying to plot data containing lat, lon and variable (nmf2). The grid isn't a regular one, so there are some ...
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39 views

Proof low deviations in DEM compared to point dataset

I am not sure how to achieve the following consistently: I have a regular distributed point dataset (surface elevations). From this I derived several DEM using QGIS IDW Interpolation method. Now I ...
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60 views

Converting DEM to Floating Point Raster (FLT) using QGIS?

I am looking to convert a .DEM exported from AutoCad to a floating point raster file type (.FLT) utilizing QGIS to implement in HEC-RAS Mapper. This is accomplished easily in Arc using the ...
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34 views

How to extract values from raster at points with many different rasters and points

I have a folder containing 100 DEM rasters. I have a point file containing thousands of points. I need to collect raster values at all of these points. Only some of the rasters intersect with the ...
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30 views

can i comparing landsat 7 and landsat 8 thermal band?

can i comparing landsat 7 (band 6) and landsat 8 (band 10&11) thermal band? because landsat 8 only have 100m spatial resolution, so the output looks more general or blurr than landsat 7 thermal ...
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Automate Exporting of Rasters Using Renderer in ArcGIS

It is possible to export rasters in ArcMap by right clicking the layer-> Data-> Export: You can then click 'Use Renderer' check box to ensure the image you export uses the current ...
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166 views

Assigning RGB values from Geotiff image to LiDAR data, using R

I have given a Geotiff image and its corresponding Lidar data (x,y,z) in UTM coordinates. I need to merge the Lidar data with the RGB values from the image. That means, at the end, I need to plot ...
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25 views

Get Raster Values from a Polygon Overlay in ArcGIS

I have the same problem as Curlew in Get Raster Values from a Polygon Overlay in Opensource GIS Solutions and thecrashlandingdodo in Step-by-step: How do I extract Raster values from Polygon overlay ...
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28 views

Adding polygon attribute to a gdb raster

I am working with the gSSURGO soil database which has many tables with data and one raster file. I managed to join the tables to the raster, so now I click on my map and can see all raster attributes. ...
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99 views

How to make maps out of imagery?

I am working for a client and we chose to use OpenGeoSuite as our system. Our client will be flying a plane over farm land capturing images that we need to put in our system. From my understanding ...
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Pixel based transparency or “Lighten” on geoserver

This is similar but different from this question. I'd like to statically assign a transparency of one raster based on another raster. For example, say I had a raster of aspect in a spectral gradient ...
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26 views

Add QGIS raster layer to Google Maps API

Is it possible to add a hosted QGIS Raster layer into a Google Map? Thanks.
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19 views

Problem with QGIS raster interpolation from a point shapefile after duplicating the shapefile

Let me explain a problem I had with QGIS to see if somebody else has experience it. I created a raster from a point shapefile through the Raster-> Interpolation menu with no problems. After that, I ...
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2answers
240 views

Rasterizing polyline data with QGIS/GDAL: custom line width

I need to make a raster from a polyline shapefile. However, when I use gdal_rasterize (either directly or through QGIS), all my lines are drawn one pixel wide, while I need them to be drawn with the ...
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626 views

How to Iterate through Bands of Raster using ArcGIS 10.1 ModelBuilder?

I have a large number of rasters with 3 bands (R,G,B). What I want to do is add all 3 bands of each raster together to end up with a single band image with the summed R,G,B values in each pixel but ...
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38 views

chi-squared for two rasters in R

I am kind of new with statistics. I have two raster with categorical values and I want to get chi-square. How can I do this using R? Rasters have the same region and same resolution. Is chi-square ...
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354 views

R Raster package loop over pixels

I want to perform a trend analysis for each pixel over it's time dimension. Therefore I wrote a loop over each pixel doing the calculation but this is extremely slow. I am sure there must be a faster ...
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129 views

Export Multiple Raster Data with custom Cell Size

I Have 172 Raster, and need to change the cellsize. So I use Export Data from TOC and change the cellsize manually (example I want to change it to "3") I tried using this python script to ...
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30 views

Euclidean Distance with Weighted Values

I am currently dealing with a dataset which consists of about 2700 points stochastically placed in a study area of about 650,000 sqKm. I am trying to create a distance raster for these points, which I ...
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20 views

Merging rasters in Openlayers

I'm using Openlayers 2.13 and GeoServer 2.5.2 and I want to merge rasters. After short searching on Internet, I haven't proper, not even close, solution for this. How can i handle this? Thanks in ...
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41 views

Using Polyline to Raster tool in ArcGIS

Pretty basic question; In this Polyline to Raster tool, there is a field called "Value Field" I am not sure what to put for this field. My polylines are ZM, so there is Z information for the line, I ...
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22 views

Clipping a Raster into 5x5(25) equal tiles through the use of arcpy?

I am curious to find our if there is a way to create a python code that enables you to clip a raster into equal parts example: 5x5(25) tiles with the use of arcpy? From what I can think of you would ...
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55 views

Where do I get Elevation Data for Scotland?

So I am new here and I arrived here because I have been searching for quality elevation data for the entire Scotland but I have not succeeded yet. Kindly help if you know where to get the data Raster ...
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32 views

QGIS raster from interpolation not scaled correctly

I am using the interpolation plugin in QGIS to interpolate values within a boundary. I start with two layers; 1) my points and 2) a polygon for the area of interest. Then I go to ...
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33 views

ClipRaster with three inputs

1) How can I clip raster with checked "Use Input Features for Clipping Geometry? I don't want to specify X, Y Min/Max for the Output Extent. I want to run a simple Clip Raster script that includes 3 ...
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73 views

QGIS SAGA Raster Calculator

I am using SAGA --> Grid Calculus --> Raster Calculator on QGIS version 2.6. The formula I am using is: ifelse(gt(a,0), (a), b) where a is my layer with values in a greater extent than that of b. ...
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19 views

is it possible to create gis web application that can clip raster images using vector layer shapefile?

I need to create a web application that can navigate through the world or even single country and let the user draw or upload polygon shapefile to clip raster data according to that drawn or uploaded ...
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30 views

True color combination using Resourcesat-1?

I am working with an image from India. According to the metadata, I am working with an image acquired by the AWiFS sensor from Resourcesat-1: ...
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48 views

Intersection of two Raster objects

I have two raster objects r1 (in grey and green) and r2 (in pink) that I want to intersect with R. I tried with the R function intersect from the raster package but it only intersect the extent of the ...
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118 views

Getting latitude and longitude raster from DEM

Could anyone please provide with a way to calculate latitude and longitude from DEM, for each raster cell? In previous posts about this, I have seen that some suggest calculating lat and long in ...
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21 views

Computing View Distance in One Direction from Point on Elevation Raster in PostGIS?

I'm a software developer just getting into GIS, so please forgive me if I don't use proper lingo, or if I use proper lingo incorrectly! I have a raster of elevation data. For a given point in the ...
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31 views

Problem rendering raster in QGIS

I have a problem with some Landsat 8 bands combination. I created a multiband (1 to 7) file in order to avoid the creation of several files with combinations and instead, have all the bands in one ...
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40 views

The truth value of a raster is ambiguous. Invalid use of raster with Boolean operator or function.

I'm having trouble with an if/else statement in my for loop. I have a raster Vmax with a constant value, another raster V which has a value of 0 in the beginning and will change during execution of ...
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115 views

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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84 views

Is it possible to add a raster file as layer from an URL?

I have several geoTIFFs stored on a server that I can access through http. I would like to add them as raster layers analogous to adding a local raster file through the "Add Raster Layer" button, but ...
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44 views

Does interpolation create a vector or raster?

I have been reading about interpolation and am trying to understand whether interpolation results in a vector or raster. Say I have a layer of points and I am interested in creating a raster that fits ...
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18 views

Combining several raster files generated from polylines

Maybe I'm just missing the point somewhere... I'm working on a path distance analysis, specifiying the cost layer. For this I have built a model, where I have roads and trails, both polylines, that I ...
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1answer
41 views

QGIS georeferencer: Thin Plate Spline (TPS) residual

1) Is anyone able to explain in simple manner what does mean error exactly mean? I use metric values, so suppose 3.64109 is expression of meters and "e" is mathematical constant: ...
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119 views

Calculating road density in R using kernel density

I have a large (~70MB) shapefile of roads and want to convert this to a raster with road density in each cell. Ideally I'd like to do this in R along with GDAL command line tools if necessary. My ...
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64 views

Error adding MrSID raster layer to QGIS for Mac OS X 10.10.2 (Yosemite)

I want to add a MrSID layer to QGIS (version 2.6.1) with a computer running Mac OS X Yosemite. I installed QGIS through macports from the terminal and all python packages through macports, as well. I ...
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39 views

Dealing with NoData Values in Arcgis

I have a set of rasters which I want to calculate mean of them,these rasters has some NoDate values,I have two approaches first using this code in raster calculator I interpolate them ...
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69 views

Removing salt and pepper effect

In a land cover raster (categorical map) that is a product of classified satellite image, what is the best way to remove "salt and pepper" effect from the image after classification. I am not ...
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24 views

How to turn a vectorgraph into raster correctly?

In QGIS2.8 version, I added several points in a point vectorgraph. When using the grid - > Conversion - > rasterized vector , The results turn out into a black figure. How to turn a vectorgraph into ...