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

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How can GRASS export an .flt file?

I am using GRASS and connecting it to another application. The other application needs an FLT file of the raster map which I should export from GRASS. The other application only reads FLT files. Can ...
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144 views

Clip GAPAnalysis and save as a new file output strange looking colors

I download USGS GAP Analysis and use a polygon to clip raster from that GAP Analysis. I am wondering why there is a strange looking color when you clipped the raster. If you zoom in, you can see ...
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447 views

How to use r.patch with two maps having different colortables?

I am using r.patch to combine two raster maps in order to fill in the null values of the other. Is there a way to use r.patch but still maintaining the colortables of the separate raster maps? I do ...
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280 views

Creating color table file in PCI Geomatica

What is the simplest way to create a stand-alone color-table file in PCI Geomatica (PCT or STR)? I have some classified imagery with values ranging between 0-255 and I would like a way to ...
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21 views

Unsupported Source

If I try to save a raster files from a WMS once saved tells me that the source is not supported, "Data Source not supported: /Users/beatriceluise/Desktop/wms/Senza titolo.tif is a raster data source ...
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26 views

Spatial correlograms for binary raster?

I have binary raster data (deforestation hotspot or not) that I would like to plot spatial correlograms for in R, to look at spatial autocorrelation over different spatial lags. I came across this ...
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19 views

PostGIS raster to UTFGrid

I am trying to create a UTFgrid JSON with a Raster in PostGIS. The goal is to provide weather data for web maps. I found some libraries: https://github.com/Ecotrust/create-utfgrids ...
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22 views

Per-pixel Descriptive Statistics through multiple Raster layers

I'm looking for computing different descriptive statistics through a set of raster layers. I need to make it with a python script capable of running into a standalone tool within the QGIS. To do so ...
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16 views

How to “clean up” undesired values in a slope raster

I have a reclassified slope raster with 3 values in band 1. My problem is that I want to polygonize this layer, but the surface is so irregular with a lot of plots in terraces and because of this it ...
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57 views

Problem aligning historic map of Poland [closed]

I have downloaded a historic map of Poland. I am having a problem aligning it to a modern map. I have tried various methods and coordinate system using over 50 points, but nothing works. It gets ...
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28 views

Combining Data from raster and polygon

I am teaching myself GIS at the moment, and there are still some matters I haven't quite got the hang of. I'm using ArcGIS 10.1, and have three datasets: LAYER 1: A population dataset at a high ...
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ArcGIS, Combine tool. Crashes once reaching 40% progress

I'm trying to combine 7 rasters containing soil related data. Rasters are 4.5G, give or take. All the rasters contain integer values. Once the combine tool reaches 40% progress, it stalls and arcmap ...
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26 views

Arcmap - raster positioning on the map

I work in Arcmap 10.3.1. I have raster dataset - spatial reference 3413 My problem is that I can not send this data on a map. Sequence: Add raster dataset Add basemap How do I display the ...
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32 views

How to integrate set of neighboring pixels in raster dataset?

I generated peaks of tree crowns as an individual pixels from DSM dataset, but there are some trees that have more than 1 peaks. I would like to integrate them based on the threshold value, for ...
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49 views

How to select lines affected by sea level rise?

I'm doing a part for my master's thesis where I'm trying to find out which sites located near the coasts of Sweden that will be affected by sea level rise. I got a DEM with height data and have to ...
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16 views

Swapped axes in R raster brick plot from netcdf

I am using the R raster package to import a tiny sample netcdf file, available here: https://www.dropbox.com/s/fht4g52p948vxva/persiann.ncml.nc?dl=0. The main data website is: ...
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23 views

Remove raster pixel in R

This is the 32 year trend NDVI (raster data) I would like to remove the green grids data by using R (the green pixel value is larger than 0.03) and this one is R code that i use but i cannot ...
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17 views

R: how to export my Kriging result to raster? [duplicate]

I want to export results of my Kriging calculation to raster or some other format. My aim is to take this converted file and intersect it with another SpatialPointDataFrame (location of the point ...
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12 views

How to query raster in PostGIS within GeoJSON mask only

I have a raster in PostGIS which I need to query pixel values from, but only within a specific area. So I have a GeoJSON polygon within which I want to extract min/max/avg values of the raster from. ...
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14 views

R Freezes when Plotting Spatial Data Frames

I have run into a problem where anytime I try and plot a Spatial DataFrame in R, the console freezes, regardless of the size of the file. I imagined this must be due to an issue with the path to one ...
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22 views

How to get all pixel values of raster within a GeoJSON FeatureCollection in PostGIS

I need to extract all pixel values in a raster within a GeoJSON mask, using ST_Intersects. Attempt (throws invalid GeoJson representation): select row_to_json(t) from (select * from table_name where ...
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22 views

Error in rasterToPolygon trying to get several coverage layers

I have a very strange problem: I am trying to get a raster with coverage from 0 to 1 in each cell for types of vegetation, I started with a raster of vegetation type, but I needed a raster with 12 ...
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23 views

Zonal Statistic Tool

In ArcGIS, I have a grid 5x5km (I have it both in vector and raster formats) I want to calculate, based on this grid, the zonal statistic (MEAN) of a raster 30x30m pixel size. The raster overlaps ...
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22 views

Raster Precision QGIS

I am using r.patch extension in QGIS to join a number of LiDAR tiles, some of which overlap hence i am carrying out this task before utilising in a hydraulic model. R.Patch works fine, however the ...
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41 views

Generate ESRI grid with xllcenter/yllcenter in header

I'm trying to generate ARC/INFO ASCII GRID (*.asc) from point feature class using Create TIN - TIN to raster - Raster to ASCII functions. I'm looking for a way to have the output raster file header ...
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24 views

Selecting cells with values from DEM those are above specific value corresponding to each polygon?

i have a shapefile with 2000 polygons and a DEM. i want to calculate zonal mean for each polygon considering values from DEM which are above a particular value for each polygon. i want to it with ...
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40 views

Reclassifying raster analysis (like the one in ArcGIS Spatial Analyst) in QGIS [duplicate]

I am trying to reclassify raster (DEM) in QGIS. I know how it is done in ArcGIS (Spatial Analyst, reclassify option), but I would like to know how it is done in QGIS?. The point of my exercise is to ...
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43 views

Convert a raster with one band into a raster with RVB bands on QGIS?

So yesterday i downloaded a raster tile on a WMS server and exported it with Grass. I get a raster with 3 bands, i treat with the Semi automatic classification Plugin in QGIS and it works perfectly. ...
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24 views

Polygon to Raster: Cells with multiple values

I'm trying to use R to rasterize a number of shapefiles and I'm having trouble dealing with cells on the edge of shapes, in other words the if a cell is partially covered by an NA value and partially ...
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38 views

Can raster maps be stored in a SQL Server spatial database?

Can raster maps be stored in a SQL Server spatial database? And if so, how? ... I'm aware of VARBINARY and FILESTREAM for images, but can only see GEOMETRIC and GEOGRAPHY for vector data
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problem with raster calculator syntax [closed]

I am trying to build a raster representing the output from a logistic regression model. i keep getting syntax errors. heres the script: -2.41-(15.97 * "Topographic_Predictors\wadem10m_annsolrad") - ...
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35 views

Raster package limitations

I am very new to R and to raster package and I was hoping that someone could provide some guidance. I am trying to run a function that averages a series of rasters, 300 to be exact, they are in geotif ...
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44 views

Python error in Qgis 2.14.0

I'm trying to build virtual raster (catalog) following instructions from the documentation in QGIS.. It appears the following error in python code: 2016-04-17T12:13:07 1 Traceback (most recent call ...
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62 views

Slow performance clipping raster with GDAL

I have a few large LiDAR DEMs that I want to merge. Each DEM has some glitches around the borders which need to be removed in order to get a seamless final product. I manually traced around each DEM ...
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25 views

Curve Number equation

I have a floating point raster of Curve Numbers (70-91) and I'm attempting to use the curve number equation to create a weight raster for flow accumulation, to determine runoff for a single rainfall ...
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18 views

Reduce raster resolution and determine pixel inclusion based on % pixel overlap

I'm trying to reduce the resolution of a raster from 1m to 50m using a pixel aggregation (average) method, but I need to set a threshold for inclusion (e.g. 75% of the 1m pixels must fall within the ...
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29 views

Add raster attribute table to raster using arcpy

I have downloaded US soil raster data by state from https://gdg.sc.egov.usda.gov/GDGOrder.aspx at 10m resolution. I am now trying to add a modified raster attribute table to tif that was exported ...
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16 views

How does “Mosaic to New Raster” tools works? How does it treat pixel values?

I'm working with arcGIS. I have mosaicked 8 rasters with values ranging from -408 to 180. The new mosaic shows pixel values ranging from 0 to 180.Then I compared cell by cell values from the original ...
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Map netncf-file with different years and save the different layers in shapefiles

Download from this website the following netncf-file: cru_ts3.23.1991.2000.pet.dat.nc.gz. This is a monthly raster with data from all over the world from january 1991 to december 2000 I am using ...
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39 views

Clipping raster brick object in R

I have MODIS NDVI TIFF files for a year I want to first clip it with a irregular polygon (not by its extent only) of my study area and save it as a multi band raster in TIFF format The TIFF image are ...
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56 views

What method does QGIS Merge Rasters tool use?

I am trying to merge rasters in QGIS and want to set a priority order for merging so that the values from the highest priority raster are used in overlap areas (the “FIRST” merge/mosaic method, I ...
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25 views

Adding rasters to mosaic dataset?

I'm working with an ArcSDE geodatabase v 10.0 in SQL Server 2008R2. I added more than a dozen of rasters w/o problem. Server: WIN 2008R2 12GB RAM SPACE: 1TB Created a mosaic dataset (empty) w/o ...
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40 views

PostGIS clipping raster with the same color band as the original raster

I am trying to clip a raster so that the clipped raster would have the same minimum and maximum values for the color band as the original raster. For example if i clip the raster with this command: ...
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27 views

Control points in IAdjustXForm for georeferencing of raster (ArcObjects)

I am trying to create a georeferencing tool using ArcObjects in VB.Net. Though only a little text is available on this topic in forums as well as from ESRI; I found an esri article that states the use ...
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Calculating the distance between points and parts of a underlying raster set

I need your help with a calculation of the distance between points (cities in this case) and forest (raster data). Is there a possibility to collate to every city the distance to the nearest forest ...
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How to unckeck automatically the “No Data Value” predefined on raster background on QGIS 2.14?

I'm trying to import a bunch of rasters, but there is a parameter predefined on the TIFFs, where says that No Data Value should be marked. But I need this unchecked. I opened the metadata, and found ...
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37 views

Finding and loading global population density raster data into R?

I am using the Bioclim dataset for a maxent project right now, but I want to add demographic predictors along with climatic ones. I have the 19 layer raster data from Bioclim and I'm hoping to use the ...
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46 views

How to speed up raster2pgsql?

I'm trying to upload a 37 GB raster dataset to PostGIS. The raster is out-of-db (-R option), so the actual pixel values are not stored in PostGIS. I'm using this command: raster2pgsql -s 25833 -C -I ...
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37 views

How do I get rid of edge effects while using focal in R to smooth a raster?

I am trying to use R with the focal function from the raster package to smooth raster images. I am working with Radar images that have already been preprocessed. As part of that, some calculations ...
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71 views

Why do I get “Insufficient memory for image” although there should be enough RAM?

QGIS reports "Insufficient memory for image 1403x716", when I want to load a raster. The problem begins after 1 hour of work. Had somebody had such problem? System win7 64 bit, 16GB RAM, Intel Core ...