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

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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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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 ...
0
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1answer
36 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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22 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

Create RasterDataSet from 2d array

How i can create RasterDataset using a 2D double array : double[][] pixels OR float[][] i tried tow ways using IRasterDataset 1- IPixelBlock outBlock = outRawPixel.createPixelBlock(pnt); ...
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35 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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0answers
49 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 ...
3
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1answer
93 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 ...
2
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1answer
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
47 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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2answers
40 views

Merging raster data in QGIS using wildcards

I have a problem merging raster data sets in QGIS, and I have searched various forums, but have not found a solution yet. An "ordinary" merge, for example merging the raster files ...
1
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1answer
55 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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2answers
46 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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2answers
55 views

Combine overlapping rasters and include cells with no data

I'd like to combine about a dozen rasters into one raster that contains the "summed" cell values where overlaps occur. In doing so, I need to be able to retain cells that either have no data, or that ...
1
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1answer
48 views

Coordinate system ID ArcGIS

I have satellite image files with metadata generated from ArcGIS: Raster Download Information Coordinate system ID WGS84: 4326 Top edge WGS84: 35.0003681085064 Degree Bottom edge WGS84: ...
0
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1answer
79 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 ...
1
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1answer
52 views

Conditional statement, apply different equation based on raster value R

I am trying to find the best way to apply a set of equations to a raster conditional on values in a separate raster. For example, suppose r1 has the values of interest and raster 2 (r2) is a raster ...
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1answer
42 views

Convert a lat, long, value table into a raster

I would like to to convert a table with latitude, long, and a value into a raster. My file looks like this: X Y Z 32.85138942 -6.643054718 0 32.85138942 -7.059721474 1004 32.85138942 ...
2
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1answer
32 views

Loading Raster using QGIS API in Windows

I am trying to develop a C++ application using QGIS. I have to load a tif file and show it. First I wrote an app similar to samples on the internet. It works on Linux, but it does not work on ...
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1answer
82 views

QGIS 2.8 Convert a vector to a raster layer

When I change a vector layer to raster using raster button->converse->Vector rasterization in QGIS2.8. I get only a black picture. Why is that so and how can I convert a vector layer to a raster ...
0
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1answer
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 ...
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1answer
64 views

Qgis raster calculator not giving output

I want to calculate some result using QgisRasterCalculator and using the code mentioned below.Problem is i am not getting any output raster also if i use this formula in raster calculator it gives ...
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0answers
28 views

Creating raster from points that conforms to a reference geometry using PostGIS, python, QGIS

Please forgive my ignorance, I'm fairly new to processing GIS data. My bread and butter is statistics but I'm now working on a project that requires more data preprocessing and cleaning than I've ...
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2answers
31 views

How to compute climatology of 3 days moving averages for rasters pixel by pixel?

I have one year of datasets that I want to compute the climatology of 3-day moving averages and then I subtract this climatology from the original values for each pixel. example: # Set up the ...
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31 views

Overlay polygons on raster in different projections

I'm overlaying polygons on a raster to get the average value inside the polygon (using SAGA->Shapes-Grid->Add grid values to shapes in the QGIS Processing Toolbox), using a geographic and a ...
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28 views

Weighted Overlay not showing all values

In a ModelBuilder, my final step is to add a weighted overlay at the end. I have 4 reclassified layers as the input, all equally weighted and all contains values 1-10. However, when I run the Weighted ...
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37 views

Project Raster Data Loss - 2 Billion People

I am using the SEDAC/CIESIN raster data for population counts. This data is in WGS1984, and I want to project this data to a Fuller projection. After running through "Project Raster" in ArcMap 10.1, ...
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1answer
28 views

Raster Calculator or Local-Combine tool? (in ArcPy)

i have 3 classified rasters and i wanted to use the following query from r. calculator: (rclslope>=45) & (rclmosaic>=2000) & (rclfocal>15) to arc.py how can i write it? Is it ...
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1answer
39 views

QGIS how to save loaded min/max values for raster layers?

I am working with many layers. Each time I open my saved project, I must reload the min/max (properties/style) values. Is there a way to turn off the default 2% cut?
2
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1answer
120 views

Reprojecting a raster image using gdalwarp

I am trying to reproject an ECW Orthophoto from 25830 to 23030 srid. I tried the following but I am getting an error: C:\Program Files (x86)\FWTools2.4.7>gdalwarp -s_srs 25830 -t_srs 23030 ...
0
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1answer
57 views

Creating an R factor raster in RUSLE Soil Loss equation with multiple input rasters

I am attempting to obtain the rainfall erosivity "R" factor for the RUSLE Soil Loss equation using rainfall PRISM 30 year history data. I have both monthly and annual data that comes into ArcMap as ...
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47 views

OpenLayers/Geoserver - can I create a tiled, zoomable raster layer?

Still a relative newbie with Geoserver and OpenLayers. Developing an application with Geoserver in the back, OpenLayers (3.0) in the front. I have a requirement to display imagery on top of a base ...
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16 views

Reprojecting a ECW raster with fwtools [duplicate]

I have a ECW Orthophoto and i want to repoject it from 25830 to 23030 srid. I haven´t found a free software to do this but i heard of a command line utility called FWTools that could do the job. I ...
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1answer
95 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. ...
5
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1answer
145 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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28 views

Aspect Patch Count

I am using ArcMap to create aspect maps. I want to find the how many different directions the land faces (total aspect patch count) with continuous patches greater than three. So for example I want ...
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1answer
43 views

how can I make “weighted sum overlay analysis” in QGIS? Ordered Weighted Averaging manual may be useful

I have weighted raster data converted from polygons with different categories. I have ArcGIS with 3D Analyst extension, unfortunately do not have Spatial Analyst, and I would like to use QGIS to make ...
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31 views

Point to Raster Converting Result

I had a problem with Point to Raster converting result. I had an Excel file which contains x, y and z values. I wanted to create an individual raster data from classified z values so I planned to use ...
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2answers
152 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 ...
3
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1answer
75 views

Numbers containing e in ArcGIS?

In ArcGIS when I try to calculate some raster values or statistics, sometimes I get values that contain e, for example: 1.4e6. What does e mean, and how is it interpreted in ArcGIS?
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2answers
113 views

Multiply Rasters from two subfolders

I have two subfolders with Rasters named with the same parameters. I am trying to figure out a way to Loop a multiplication of each raster into a folder with its pair of the other subfolder. Looks ...
0
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2answers
63 views

Zonal histogram for each region (row) in a polygon (table) with python script

I have DEM.tif (symbology uses equale interval - 100m) and a polygon file (regions.shp) with many regions (names are defined in 'reg_name' column). I would like to use Zonal Histogram to produce ...
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2answers
124 views

How calculate pixel by pixel the mode (statistic) of multiple rasters (geotiff)?

I have 12 land cover maps, and I would like to calculate the mode to each pixel of the 12 maps (they have the same resolution and dimension). I mean, the final map would be the mode for each pixel of ...
2
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1answer
46 views

Create Raster Surface from Points and Equations in ArcGIS

I want to use point data to create a raster surface which distributes the values over space, as defined by an equation, and NOT by interpolating. I have an equation to describe how the characteristic ...
0
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0answers
26 views

How to avoid a problem of one pixel when doing non-linear regression?

I am ruining a non-linear regression using nlsLM from package:minpack.lm for multiple rasters (pixel by pixel). My initial values may be appropriate for some pixels but not for others.When I run the ...
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3answers
192 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 ...
2
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1answer
35 views

How do I count the number of cells which can see each cell in QGIS

For each cell in a DEM I'd like to count the number of cells which can see it (i.e. direct line of sight) - Can anyone explain how to do this in QGIS? Thanks,
3
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1answer
123 views

Unsupervised classification in QGIS

I was trying to learn unsupervised classification in QGIS 2.6 following the tutorial video: https://www.youtube.com/watch?v=mI80eENtWSE When trying myself, clicked Run during the process it shows the ...
0
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1answer
65 views

Can't import libraries to rsaga

I get this error when I'm trying to import a raster to RSAGA: > rsaga.import.gdal(paste(rast_name, ".tif", sep=""),"RASTER", env= my_env) Module 'GDAL: Import Raster' not found in SAGA library ...
6
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1answer
116 views

How to perform a non-linear regression pixel by pixel?

Using nlsLM from Package ‘minpack.lm’ is straightforward for a simple example like this: MODEL:y=(exp(a*x+b*z+c)+d)^f x=c(0.5,0.3,0.2,0.4) z=c(0.1,0.6,1,0.9) y=c(0.2,0.3,0.9,0.9) ...