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

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4
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243 views

How to change field name in raster file?

I´m having a bit of an understanding problem with a DEM TIF file. I have a DEM TIF file which is served with Geoserver. When I click on the layer the WMSGetFeatureInfo gives me the following output: ...
0
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1answer
28 views

Extracting Data from Raster based on Aspect Raster file

I have 2 rasters, ones shows aspect and another shows date of snow thaw. I want to extract the date of snow melt based on values from the aspect raster. For example I want all the snow thaw dates from ...
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44 views

How should i combine these rasters?

I have two buffers that i want to combine. I tried overlay with fun=function(x,y){return(x*y)} but 0*5 = 0 so it produces NA's.I don't know how to combine them the one buffer should be 500 and the ...
0
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0answers
28 views

Cannot find information about my.table table in raster_columns

I am running PostgreSQL 9.4 and PostGIS 2.1 and have loaded a small piece USGS SRTM data for North America successfully into my database. I am attempting to export a small piece of of the rasters I ...
3
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1answer
53 views

Does gdal_calc only support 26 input raster files at a time?

In gdal_calc.py, input files are specified with letters A-Z. Here are two files, input.tif and input2.tif, being averaged into result.tif: gdal_calc.py -A input.tif -B input2.tif ...
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0answers
17 views

Reclass by Table giving output with only 8 catergories

I am attempting to reclass a raster from a table (using the Reclass by Table tool in Arc 10.3). The output value field I am trying to reclassify to is long integer format with values ranging from 0 ...
2
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2answers
46 views

How to sum pixel values of a floating point raster in ArcMap?

I have a floating point raster with values from 60 up to 95 (with decimals), it has 7077 pixels of 250x250m size. Is there a way to sum all pixel values of this raster? For example, if the raster had ...
0
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0answers
13 views

What is the recommended approach to client side clipping, by geometry, of an ArcGISImageServiceLayer?

I have an existing Esri Silverlight application with an ArcGISImageServiceLayer and we need to add the ability to clip that raster, by a geometry. And ideally, do this on the client side since the end ...
-1
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1answer
58 views

How to reclassify a raster in R?

wet<-readOGR(dsn=".",layer="shp") #wetlands r.raster <- raster() extent(r.raster) <- extent(wet) res(r.raster) <- 100 wet.r <- rasterize(wet,r.raster) #rasterize plot(wet.r) ...
1
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2answers
45 views

Editing .tiff rasters in Python

I am triying to edit .tif rasters in python, but I have some issues regarding the tiff to array converstion. I read there are multiple options for opening rasters (gdal, PIL, matplotlib), but which ...
2
votes
3answers
472 views

Raster map in different zone () than region ()

I am new to QGIS (just installed QGIS 2.0.1) and am having problems running any spatial analysis tools. I followed the instructions on how to call GRASS tools into QGIS, but when I try to run the ...
1
vote
1answer
164 views

How can I create an animation with raster data in qgis?

I have 4 raster images showing different coniditions of air flow distribution at different times. I'd like to create an animation to show the change from image 1 to image 4. How can I do this? I tried ...
3
votes
1answer
532 views

Build Raster Attribute Table with GDAL Utilities

Is there a way to build a raster attribute table using one of the GDAL utilities? I know you can view it using gdalinfo and I have successfully created one using Python, but it would be so much ...
1
vote
1answer
82 views

How to round pixel values of a raster in QGIS?

I have a raster with float number values for example: 2.544459104537964 and I want to round these up to intergers. I have seen other posts on ArcGIS like this one but when I use Raster Calculator in ...
2
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3answers
60 views

Combining rasters to calculate total inputs

I am working on creating a map of total chemical inputs into a study area. I have several raster layers of different inputs with values stored in the attribute tables. I am having a hard time ...
1
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2answers
630 views

How to create a raster (topo to raster) with non-rectangular shape?

I'm using Arcmap 10, I need to create a raster from contour lines. These contour lines were clipped out with a certain shape with the purpose to modify them only within that shape and then create the ...
3
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1answer
63 views

Split raster into tiles

I have a raster that needs to be split into tiles (each tile a new raster). I have a Shape file with multiple polygons (these polygons are how I want the raster split). I have Gdal and QGIS. Any ...
3
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2answers
117 views

QGIS print composer export excludes one layer

I am trying to export a map from QGIS print composer but the resulting files (I've tried all image, .svg, and .pdf formats) do not appear as the map did in the composer. It is as if one of the raster ...
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2answers
63 views

GDAL raster shifting with python error: 'NoneType' object has no attribute 'GetGeoTransform'

I'm trying to shift a georeferenced raster by 0.5m N and 0.5m W in QGIS using the python console: from osgeo import gdal # Open in read/write mode rast_src = gdal.Open('test_raster.tif', 1) # Get ...
1
vote
1answer
76 views

How to reproject a raster from lat/lon to UTM in R?

i have to turn it into a UTM in order to make the buffer functional. wets<-readOGR(dsn=".",layer="shapefile") r.raster <- raster() extent(r.raster) <- extent(wets) res(r.raster) <- 100 ...
2
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1answer
34 views

how can I get the majority (dominant) class of a raster to an area (polygon) using qgis?

I have a vector layer with many basic units of planning (zones), a raster layer with three classes of geology and other raster layer of geomorphology with five classes. How can I update the ...
0
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0answers
30 views

Combining tiff with shapefile

I have a geotiff image with a D_WGS_1984 Datum of land cover for the continental US and I want to be able to merge it with a US counties shapefile. What is the fasters and best way to do this? My ...
2
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1answer
234 views

How to iterate GRASS region definition?

I am using GRASS r.skyview command (v.7, Windows) to determine "urban canyon effect" on pollution due to the presence of buildings. The command nicely works, unfortunately I need to process a very ...
0
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1answer
53 views

How to rasterize a vector dataset in R?

I would like to compare vector vs raster data. So i try to fix a problem using both ways. I made it in vector first : coastline<-readShapeSpatial("shp") wets<-readShapeSpatial("shp") ...
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54 views

Raster map source for desktop, commercial application

We develop desktop, commercial application for Architects (c++). In a future update, we would like to provide our customers with the option to automatically create a 3D terrain with appropriate ...
0
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2answers
48 views

How to export query result on raster table in PostGIS

I did success query on a raster table in postGIS(raster data clipped by a vector polygon), now I want to view the query result in QGIS. But how to export the query result to another table. In vector ...
0
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1answer
364 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 ...
7
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2answers
502 views

Using ArcGIS to filter cells where 7 or 8 of neighbors are different

I have land cover data that I would like to clean using some generalization tools. Majority filter does almost exactly what I want, but is missing one key option. Majority filter allows you to change ...
0
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3answers
39 views

Selecting parcels in vector map from raster layer using ArcGIS for Desktop?

I am relatively new to Arcgis and I am stuck. I have a parcel map (vector) and a land cover map(raster). My land cover map is only 1's and 0's, flood and no flood. I want to be able to highlight or ...
0
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32 views

Problem with calculating slope in QGIS

Ive downloaded DEM form earthexplorer. But after calculating slope I only have blac img. with same value in min. and max. When calculating aspect or relief, DEM works correctly. Have you met with ...
4
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1answer
108 views

Raster to vector (polygons) with generalisation

I have created rasters showing different types of vegetation (bushes, trees, open land) with help from lidar data. Now I'm looking for a method to turn these images into polygons. I'm using a Mac ...
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0answers
16 views

Replacing white or black by alpha channel in raster in QGIS 2.8

I'd like to replace black or white in black and white raster in QGIS 2.8. I perceived that in some other raster where "nan" value automatically occurred and only white or black is being displayed.
0
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1answer
180 views

Issues calculating range with QGIS 2.0 raster calculator

I would like to calculate a simple range using the QGIS 2.0 Raster Calculator, but am getting strange results. I believe I am not using the correct syntax. To get all values between .003-.5, I ...
0
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1answer
229 views

problem to open a netCDF and create a raster file

I want to open a netCDF file and create a raster with ArcMap 10.2. The file contains the mean monthly temperature for Switzerland. I found it in meteoswiss web site. I tried to open it with the ...
3
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1answer
725 views

Why is Orthorectify button not active in Image Analysis Windows in ArcGIS10?

I wanted to Ortho rectify GeoEye HR imagery using existing RPC and IFSAR DTM in Image Analysis. According to ArcGIS Resource center ...
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41 views

calculate Z~F from polygon and raster

I have a polygon shapefile and raster layer. How I can calculate the elevation and area (Z~F) relationship for each polygon by using QGIS or ArcMap?
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36 views

Converting a (WAsP) vector map to a raster map with GRASS GIS

i'm quite new to GIS and i need to convert roughness data which is available in a vector format to a raster format. The final data should be on a simple 2-dimensional uniform grid with a constant grid ...
0
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1answer
146 views

Cannot get 2 raster files of same cell size to align ArcMap 10.2

I have two raster files that are the same cell size but I cannot get them to align properly. (I want the black to line up with the pink) When creating the black raster file (from using polyline to ...
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0answers
46 views

PostGIS: intersection of a polygon with 2 rasters

I'm trying to get the intersection of a Polygon with 2 raster layers in PostGIS. The rasters have the same size and pixel size and I'd like to retrieve for the polygon a list of something like that: ...
0
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0answers
17 views

“Mosaic to new Raster” just stop working

I have been using the command "Mosaic to new raster" so far successfully. Now, without changing any option from before, it just doesn't work anymore. It is something it already did: pretending to ...
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28 views

Raster NoData Issue

I have three landCover maps (2000,2006 and 2012),I am using ArcGIS 10.1, I converted them into raster (from polygon to raster 100x100 cell size), I guess because it is remote sensing maps (obtained ...
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1answer
20 views

How to get the upstream average of a raster data layer that falls into a river network?

I have a raster layer of a network of rivers and a raster layer of data I want to extract. For each pixel of the rivers, I need to know the upstream average of the data layer that falls into the ...
1
vote
1answer
31 views

zonal statistics sum on raster with same values

I was wondering if anyone knows what exactly zonal statistics sum does if all my input value raster have the same values. For e.g. Lets say I have a finer resolution raster with 10 pixel each having ...
2
votes
1answer
147 views

QGIS raster clip error: Cutline not of polygon type

I have a raster file and want to clip it, but I'm getting this error: "ERROR: Cutline not of polygon type" what does this error mean and how can I resolve it?
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2answers
48 views

Adjusting extent of raster?

the coloured file contains landuse information and it needs to have the same number of columns and rows as the DEM in the background for further processing. i can't get it to work - "clip" and ...
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3answers
1k views

Delivering map tiles in real-time without caching? [closed]

Is it possible to deliver map tiles quickly over the web without worrying about caching or seeding them? With raster map engines this is a problem because endering raster tiles is resource consuming. ...
6
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2answers
578 views

Histogram Matching Python

I am trying to do histogram matching using Python to improve the mosaicking process of multiple overlapping rasters. I am basing my code on that found at: ...
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1answer
37 views

Different number of columns and rows in raster datasets

currently I am dealing with the creation of a landuse file. I have geoprocessed a google earth .tiff-file over my DEM and created three polygon featureclasses via the editor tool containing areas of a ...
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12 views

fail to convert polygon to raster

I have a shapefile with 520 districts each with a value. I am trying to convert this shapefile to raster using feature to raster tool. Input feature: myshapefile Field: value Output raster: ...
0
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1answer
12 views

error 00289 while projecting raster

I tried to project satellite image of pixel size 2.5m*2.5m. It's in wgs84 UTM zone 44 North. I tried to project it to nepal_87 but failed. The error massage displayed was 'error-000289,failed to alter ...