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

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Error summing 2 different rasters?

I was trying to sum two different rasters and the final outcome is an error (image attached below)? The main goal is to sum the values of each pixel in those rasters (both raster files have the same ...
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29 views

Create raster with distance to feature

I'm new to GIS (and QGIS in particular). I'm trying to create a raster layer that contains the distance to shoreline for a certain region. I have both vector layers of the shoreline (line) and the ...
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38 views

Problems using r.reclass in QGIS: invalid reclass rule error?

I need to reclass some rasters, but i am having a couple of problems, i can´t generate a new raster with the reclassification using the r.reclass of GRASS. For the question here i´m using as example ...
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18 views

Calculate raster mode with r.mode - problem with decimals

I am working with a raster file that represents the percentage of vinyards by commune (e.g., municipality) in a region in France. The statistics were calculated for each commune based on surveys from ...
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112 views

Methodology for Hansen classification of Global Forest Watch?

I have just discovered amazing Hansen´s classification about forest loss and re-growth, available at http://www.globalforestwatch.org/, published in Science, 2013 as: Hansen, M. C., Potapov, P. V, ...
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27 views

Find local maxima with variable window search using ArcGIS Desktop?

I would like to find local maxima in different zones of raster file. I got five zones (zone 1, 2,3,4,5) and would like to find local maxima with different window search for each zone in arcgis ...
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31 views

Exclude Raster Cells with Value of Zero in ArcGIS 10.2 Raster Calculator Expression

I need to perform a simple calculation in ArcGIS 10.1 Raster Calculator. I am using a raster layer that contains many cells that have a value of zero. I need to exclude these cells in the expression ...
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74 views

Can I find out the exact areas which each category covers?

I have accessed a land use map and clipped the appropriate area I need to analyse. Is there a way I can find the exact areas which each category covers?
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31 views

ENVI 5: High resolution export of multiband imagery

I have to export some multiband Landsat imagery (Landsat channel combination 543) in high resolution in ENVI 5 for a Figure which I later will edit in Adobe Photoshop and Illustrator, best would be ...
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19 views

Clip .hdf (MODIS) rasters by shapefile

I am trying to do a temporal analysis on vegetation quality so I downloaded a MODIS .hds raster from earthexplorer. When I opened the file into ArcMap 10.2.2, it came as a group of 11 rasters. I stuck ...
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24 views

For loops + boxplot for raster

I have several Rasterstacks (b1_mask, b2_mask,...) of several layers representing only a determined pixel-intensity range. (So point "A" in some layers is "NA" - in others a "value" of that certain ...
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44 views

Extent from Centroids, Projection, and Resolution?

I have a file that defines a raster, although all the metadata was lost. I know the lat/long coordinates of the grid centroids, and that the grid is in a Mercator projection with a 1/12deg equatorial ...
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41 views

Arcpy script for summing pixel values in loop can't handle large number of rasters

I want to sum the pixel values of large numbers of rasters of different extents (ArcMap v10.2). 16GB RAM. I have the following code (with help from this site) which solves the different extent ...
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36 views

How to change values in a raster file at particular positions?

I have a collection of coordinates which comes from a QGSGeometry object. The shape is a polygon. example: qgsGeometry [[(75.2172,17.6566), (75.8499,17.9613), (75.5218,17.2113), (75.2172,17.4574), ...
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1answer
39 views

How to get a total amount of cells per classification type in a raster in ArcGIS 10.1?

I did an supervised classification for for this watershed. The attribute table doesn't have the count for total number of cell for each classification. I've created a field titled 'Count' with type ...
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1answer
41 views

Use field calculator to reclassify values from three different fields to populate a new field AND determine overlap with different raster

I want to reclassify values of 3 different fields AND determine if one of those fields is located inside a different polygon to populate the values of my new field. Everything is raster. I created a ...
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1answer
32 views

How to sum up values of neighbouring rasters? [duplicate]

I have a raster (25X25 meter) and I will make a new raster where each cell get the value of the sum of all the raster cells in a radius of 500m. I use QGIS. What is the best option to do this?
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34 views

QGIS Mac OSX version cannot batch write output files after rasterization

Happy new year everyone, I have been trying to batch rasterize a series of .shp files using QGIS for Mac OS X, and keep coming up against a strange problem. I am using the QGIS 2.6.1 user interface, ...
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21 views

Subset two rasters with different extent and origin (and resolution) only where there are data in both in R

in R, I have two rasters with different extents and origins (and possibly even resolution). How to efficiently take the subset of each of them only where there are data in both of them? Here is a ...
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34 views

ArcMap - Export raster symbology to a raster function template programmatically

I would like to programmatically export symbology for a raster dataset as a raster function template xml file, as can be done by clicking the export button in the symbology tab of the layer properties ...
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2answers
85 views

How to subtract rasters using the gdal_calculate command

I just want to know how to subtract two raster using gdal_calculate command? Or what is the proper way of subtracting using this? Any idea would be greatly appreciated. Note: gdal_calc is different ...
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40 views

Minimum and maximum values when raster statistics are lacking

How does ArcMap determine minimum and maximum raster values (e.g. for rendering colour ramps) when a raster file lacks an auxiliary file (e.g. aux.xml) describing statistics? This question is related ...
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44 views

How to extract percentage of land cover from a raster according to multiple shapefiles?

I have a raster map that represents land cover of a region, and different shapefiles (total 120) in the same region. I want to know the percentage of every land cover for each shapefile. For example, ...
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16 views

Rastercalc.py and Rastercalcengine.py

Is there any examples on how to use the rastercalc.py or rastercalcengine.py? And what are the purpose of these python module? Are these modules the same with gdal utilities which can be run in ...
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29 views

Reference raster data outside of GeoServer data directory

is there a possibility to point GeoServer to raster data stored neither in a database nor in the data directory of GeoServer? My problem is that IT keeps me from direct access to the GeoServer ...
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34 views

how to use raster layer (map image) as base layer in geoserver+openlayers and vector layers on top of that?

I am using Openlayers + Geoserver for rendering data on India Map. I am able to do it. However, the India map generated from Opensource shape files doesnt look good. So, I want to use Better India ...
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45 views

QGIS “ERROR 6: No translation for Lambert_Conformal_Conic to PROJ.4 format is known.”

I am trying to clip a county DEM file using the PLSS Section shape files as mask layers... that is, I want it clipped to sections so that I can load my DEM into QGIS one section at a time, without ...
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39 views

Raster statistics - incorrect and apparently arbitrary minimum value

I have projected a raster with gdal as part of an R workflow: gdalwarp -s_srs EPSG:4283 -t_srs EPSG:3577 -r bilinear -multi -tr 1000 1000 -dstnodata -9999 in.tif out.tif When I add out.tif to ...
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1answer
38 views

Problem serving clean transparency with mbtiles in GeoServer

I'm running across an issue with the display of some historic line maps that I'm trying to serve as a WMS with GeoServer. I have created a mosaic of georeferenced line drawings in ArcMap, and I want ...
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1answer
24 views

How to get depth between two spline raster layer in ArcGIS for Desktop?

I have spline raster layers of same area and I need to know the distance between layers by every pixel. I have prepared a sample drawing to define my problems. Does anybody have an idea regarding my ...
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39 views

Tiff Raster File slow to Load in Win 7 64 Bit QGIS 2.6.1

I have been unable to load a Geo Referenced Tiff file in 2.6.1, I have found it it will load but takes minutes, It will load quickly in 2.4 It is a Lidar file so it is large, about 14 gb in size, I ...
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96 views

Working with AIG Raster format in ArcGIS for Desktop?

I downloaded a specific layer which has the format "AIG" as you can see in the screenshot. It has no projection so I applied "Define Projection" on it. I searched for the projection and found the ...
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73 views

Querying slope data using raster calculator: why are all results true?

I am using ArcGIS 10.2.2. From a DEM, I have created a new raster showing slope using the slope tool. The color scheme was automatically classified into 9 tiers. What I want to do is query this raster ...
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50 views

Merge Raster Layer Specific Order in Graphic Modeler

I'm using the Graphic Modeler/Processing Modeler to automate a process. The last step in this process is Merging three different Raster Layers. I'm using the "Merge Raster Layers" from Saga 2.0.8. ...
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23 views

Creating raster(geotiff) from a text file with grid_code from arcgis raster to points

I have made a text file from raster to points via a DEM in ArcGIS 10.1 where I have inserted values in an another column that I want to display. Next to point ID is grid_code, which I believe ...
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20 views

Updating/replacing GeoTiff data store on file system causes GeoServer to halt

I have a few hundred raster layers that are updated at least 4 times a day. The GeoTiff's are updated directly on disc. I'm running it as a windows service and I can sell the wrapper app logging the ...
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Errors when using the Corridor Designer tool from Arctoolbox

I am using the corridor Designer ArcToolbox for designing a habitat suitability model and I've got the following errors: Error 010328: syntax at or near symbol SPACE ERROR 010267; Syntax error in ...
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188 views

More accurate way to calculate area of rasters

In my daily work, I am constantly asked to calculate areas of global raster datasets in geographic projection at 30 arc second resolution. These datasets are normally the result of a Combine operation ...
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21 views

Geoserver : create a rasterized polygon / dynamic fill for polygons with features from database

I decided to post here because I couldn't find any answer to my problems on the internet. So I am using geoserver 2.7-SNAPSHOT, everything is working fine but I need to implement a new function or ...
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17 views

Storing a coverage in a JDBC database

There is another question about raster data for GeoServer. Conditions: - PostGIS 2.0.3 and PostgreSQl 9.2. - I followed: ...
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46 views

How to speed up raster/map algebra in PostGIS?

I am testing map algebra with PostGIS (2.1 with PostgreSQL 9.3) on two images, and found it to be rather slow. For example, dividing two images of 7200 * 3600 pixels took 110 ~ 120s on a desktop with ...
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1answer
30 views

Incorrect vectorization from a raster in ArcGis (ArcScan)

I am trying to make a vectorization to get lines from a raster image using arcscan. I saw some users making it but using easier images with more visible lines but is not working with my image. could ...
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2answers
45 views

combine rasters into single raster with multiple field values in R

I have several raster brick objects that I would like to combine into one raster with multiple field values for each cell, but I am not sure how to do this in R. For example, let's say I have two ...
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28 views

creating multi band raster from one GeoTiff

I'm using AgiSoft photoscan to create a photo mosaic from aerial images. The images are being captured using a camera modified for NIR and RGB data capture. I want to be able to perform spectral ...
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What are the problems of loading overlapping (or the same) tifs into postgis?

I am still early on the Postgis learning curve. I have an existing table in Postgres - it looks like this: create table "public"."mytable" ( "rid" serial primary key, "rast" raster, "filename" ...
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48 views

Determine if shapefile and raster overlap in python

I am building a script in python using osgeo/gdal. I have a set of shapefiles and a set of GeoTiff raster files. I would like to have my script ignore shapefiles if they do not intersect with the ...
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29 views

Raster map & vector boundaryline data for Istanbul, Turkey

I'm looking where I can download background raster map for Istanbul (street map?), and then a boundary line file of the the 39 Districts in Istanbul. Does anyone have any recommendations?
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75 views

How to build an attribute table in a 3-band raster?

I have a 3-band (RGB) raster file from CORINE and the attribute table hasn't been built. When I try to execute the command BuildRasterAttributeTable I get an error that only single band rasters are ...
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128 views

Black edges on overlapped raster images in QGIS

I'm beginner with QGIS and I have task currently to make some GIS map/data. I downloaded 3 satellite images from Landsat by USGS (multispectral, georeferenced) and I did overlapping of images using ...
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2answers
53 views

Gdal: clipping a raster with another raster

I'm writing a simple utility to crop batches of multi-band geotiff raster files to the same (smaller) area. Using gdalwarp, I can easily crop a file using a single-polygon clipping shapefile: ...