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

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Problem loading tif into raster dataset in ArcSDE 10.2

I have over 1000 raster datasets I need to mosaic into ArcSDE 10.2. I can't use a mosaic dataset because the county I am working for wants to keep the files on an external HD, so the pointers won't ...
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16 views

How to read *.adf files into R?

I want to load .adf files into R. The data is from this page: http://www.fao.org/geonetwork/srv/en/metadata.show?id=14057 I tried the following code that I found after some research in the internet. ...
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1answer
19 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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10 views

erdas model maker [on hold]

I am doing my masters in geoinformatics. My thesis topic is MODELING OF SPATIAL OBJECTS FOR LAND COVER CLASSIFICATION USING FUZZY TOPOLOGY. I need to calculate a measure of the distance of a pixel ...
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8 views

View Oracle GeoRaster in ArcMap

I have imported SRTM DEM into Oracle 11g using FME.The block size is set to 128X128.I am able to view the data in QGIS,Tatuk and play with it using GDAl command line.Unable to view the same in ArcMap. ...
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1answer
34 views

Is every cell in flowdirection draining towards an outlet

I have created a Flowdirection map in a defined catchment. I want to find out if every cell in my map is flowing towards the creek/outlet. Is there an easy way to do this? I have created the ...
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18 views

Why can we use Raster dataset for raster migration in ArcSDE? [on hold]

Why can we use Raster dataset for raster migration in ArcSDE instead of raster catalog.
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15 views

MapServer map file shows Raster image as white

I'm using PAN image for raster publishing but the output in browser shows a full white image? Please give me the solution? My map file is ass follows: MAP NAME "terra" # Map image size SIZE 600 600 ...
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3answers
41 views

How to resample a 30m DEM to a 100m slope raster properly?

I need to resample a 30m DEM to a 100m slope raster. Do I just resample the 30m DEM directly to the 100m slope raster? or, do I convert the 30m DEM to a 100m DEM and then create a 100m slope raster ...
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21 views

Assigning score to raster based on cell overlap with other raster and field value

I have a set of rasters that I've assigned scores to individually (scored based predominantly on values of other fields). The scoring scale is the same for all rasters, but the factors that determine ...
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1answer
28 views

Where to download rasters for QGIS 2.6

Where can I download sat imagery. I've read that openlayer provide such things but it requires an internet connexion, and I mostly use Qgis with an offline computer. So do you know a way/provider (for ...
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1answer
25 views

Visualising a raster PostgreSQL table in QGIS

I have imported a raster tif image into PostgreSQL with this command: raster2pgsql -s 32643 -I -M filepath.tif -F -t 100x100 public.databassename > filepath.sql And imported the output SQL file ...
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31 views

How to calculate RMSE, skewness, and kurtosis of raster image?

I'm doing a project to analyze the impact different interpolation techniques plays on DEM accuracy. In order to do so, I need to calculate the RMSE, skewness, and kurtosis. I have: an original ...
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66 views

Difference between raster subsets as defined by another raster

I wish to determine whether there is a relationship between slope and the Corine land cover class pastures. i.e. whether areas defined as pasture have a different slope to non-pasture areas. I've ...
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7 views

Unable to execute the algorithm using SAGA LS factor

I tryed to calculate the LS Factor at SAGA, using a slope raster and the area raster, both at the same EPSG, and the error:Unable to execute the algorithm the error means something with the coordinate ...
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1answer
21 views

How to shift a raster in QGIS?

I'm looking for a tool or a plug-in for QGIS that would allow me to shift rasters to new coordinates. An equivalent of ArcGIS' Shift tool would be the best option. I know I can edit the world file ...
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1answer
14 views

Rasters change pixel size and range of values when imported into QGIS

I have observed that when I import rasters into QGIS their pixel size changes and also, the full range of the raster's value does not appear. For instance, I may have a raster with values ranging from ...
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1answer
24 views

Error converting a raster to polygons

When I am converting a raster using the polygonize tool, I get this error: ERROR 4: 'C:/Users/Vitor/Desktop/Cartografia EE_Portimo/COS RASTER/cos_raster_reeditada.tif' does not exist in the file ...
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16 views

How can i perform area calculations in a raster file?

I would like to know if is possible and how can i calculate all areas or parts of it in one raster? Can i do it using the raster calculator? All help is appreciated, Best regards
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2answers
33 views

Python Script tools for ArcGIS 10.2 is very slow (get raster properties)

I am using python script tools for ArcGIS 10.2, under Windows 8.1 64bit. When I am using the arcpy.GetRasterProperties_management() command, it's very slow to process the data. For example. I tried ...
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1answer
13 views

Raster2pgsql overview method

What is the method used by Raster2pgsql to create overview? I couldn't find details in the docs. Nearest neighbor isn't a very good choice for the dataset I'm working on, but that seem to be the one ...
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2answers
39 views

Arc - how do I find the coordinates of the centroid of a raster?

How do I find the coordinates of the centre / centroid of a raster? I have tried Zonal Geometry but this does not give me the coordinates. I need to find the centroids of two rasters and create ...
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1answer
30 views

Got different cell sizes from a rasterised data

I'm trying to rasterize the Land cover data of Nigeria which was obtained from FAO database. During the process of rasterizing the land cover data, I used the following information which gave ...
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1answer
33 views

Overlaying two raster images with no spatial reference

I have two images (X-Ray and Neutron Tomography Scan) of a human bone fragment. I want to use ArcGIS 10.2 to accurately overlay (geo-reference) these two images which have no spatial coordinates. any ...
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1answer
11 views

Open and split a 4 channel RGB picture

How can I split an 4 channel rgb pic in qgis? With the value tool I can see 4 channel. I tried to use the RGB to PCT tool but I always get an error (File "C:\PROGRA~1\QGISBR~1\bin\pct2rgb.py", line ...
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35 views

Mapinfo : How to cut a raster with a vector layer?

With mapinfo 12, i would like cut my raster layer .tab with one of my vector layer. How to do this basic task with mapinfo? Is it possible with mapinfo to convert .tab raster table toward any ...
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9 views

Transparency on black/white raster after clipping in QGIS?

I'm new to this forum and QGIS. I'ld really appreciate it if you could help me with my problem, since I couldn't find any solution online but people experiencing the same issue. It seems as if this ...
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1answer
17 views

Mosaic to New Raster not allowing correct overlap

I am not sure what exactly is causing hiccups for me - how I processed the data (removing the white edges in 3rd party software), the bit depth (8bit), the file format (png to support transparency), ...
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15 views

Slope tool output has artifacts

So I've tried using the slope tool for a DEM using an appropriate Z-factor and the output is smooth, but it seems to be over-estimating slope angle. I would prefer to reproject the DEM (to NAD 83 UTM ...
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3answers
24 views

Raster algebra to tiled maps on a sever with open source solutions

Let's say I have a collection of data in raster format. It changes daily. Once each day I would like to do some fairly complex raster algebra on these datasets. I would like to be able to do the ...
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42 views

Reprojecting a population raster from LAEA to lonlat

I have a population density raster from the EEA which is based on the CORINE land cover 2000 data. ...
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3answers
42 views

Raster calculator to create single raster with 4 values from two binary rasters

I have two binary rasters showing habitat suitability (0 = unsuitable, 1 = suitable) under current and future climate scenarios. I am trying to create a raster showing: 0 = cells that are not ...
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55 views

Load the raster image which is in TIF format using QGIS API

I am quite new inthe field of GIS. I am interested in is to load the raster image which is in TIF format using QGIS API I have followed the steps given the in the follwing link to load shape file ...
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37 views

Save rasters created by loop operation to different directory?

I have a set of rasters. I crop them all using FOR loop. Then, I want to save new-created rasters in new directory, not in my actual directory. For one raster it is easy: writeRaster(raster1, ...
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12 views

How to get background maps to show in QGIS Cloud mobile version?

we're a group in Denmark, trying to publish some maps for use on a mobile device, but although our background maps show up in the desktop version, we can't get the mobile version to show them - What ...
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2answers
43 views

Remove clumps of pixels in R

I would like to remove isolated pixels (or clumps of pixels <9) from my raster image. library(raster) # create some raster data r <- raster(ncols=12, nrows=12) set.seed(0) r[] <- ...
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Isolation and interpretation of vineyard multispectral data

I have 3 band multispectral raster imagery over a vineyard from which i have created a number of indices e.g. NDVI. The data is fairly high resolution (5cm/pixel) so shows a lot of along vine and ...
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31 views

How do you calculate a new field for a raster table based on value from a joined table?

I need to know whether it is possible to calculate a new field for a raster table based on a value from a joined table. Ideally I'd like to be able to accomplish this task without having to add table ...
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1answer
29 views

QGIS virtual raster - insufficient permissions

I'm trying to create a virtual raster in QGIS 2.6.1 64b on Windows, but I get the message: "The process failed to start. Either the invoked program is missing, or you may have insufficient ...
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16 views

How to remove spikes from grid in SAGA GIS?

I tried to get a grid by interpolating LAS file using Ordinary Kriging. But the product grid has many pixels which values strongly stands out from average surface - I mean one pixel sinks nad spikes. ...
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2answers
25 views

Getting raster values on grid nodes

I have my raster layers of Digital Elevation Model, aspect, slope and curvature for a certain region. In this region I want to apply a grid with a certain spacing in its nodes, and then get the ...
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1answer
32 views

How to write every raster from a list of rasters?

I have created a list of rasters - "norm" and run a several loops. Now I would like to write every created raster from "norm" (containing 1 layer) into one raster, having its specific name. # I can ...
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50 views

How to calculate areas in raster files

I got three files. The first is a shape file for country boundaries and the second and third are two raster files with the global land covers for 2005 and 2009. I'm thus encharged to calculate the ...
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1answer
26 views

How to change the raster format using QGIS translate?

I tried to change a raster format from .tiff to .asc using Qgis's 'translate'. As a result, I get 3 files: a PRJ, XML and a file without extension just a plain file... What could it be happening? I ...
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TIFFDirectory.getAsMetadata() is not including GeoTIFFTagSet. Any solution to this problem? — JAI

The source code appears to simply copy the TagSet List object to the IFD and then the TIFFMetadata. I don't understand where it is losing the tagset as it is in the list before the call. Anyone ...
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24 views

How do I summarize and then normalize the output of a kernel density surface?

I just finished generating a kernel density surface in ArcGIS 10.2. I would like to summarize the raster cell values as a histogram, and then potentially normalize the data. How do I: generate a ...
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53 views

r - increase speed of crop, mask, & extract raster by many polygons

I'm extracting the area and percent cover of different land use types from a raster based on several thousand polygon boundaries. I've found that the extract function works much faster if I iterate ...
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1answer
19 views

Raster Files Sizes from Point Data Extremely Different

Using ArcGIS 10.1. I created rasters from several groups of point rasters using the Point to Raster tool. All of the points groups are similar size and extents. The first group of points had a file ...
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32 views

PostGIS raster maximum number of bands?

Is there a limit on the maximum number of bands you can store in a postgis raster? I cannot find documentation on this. As far as I can remember, a geotiff allows up to the max short integer (so ...
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1answer
20 views

Efficiently working with converting vrt rasters to greyscale in QGIS?

I have large raster tile sets working well in QGIS (Ordnance Survey UK data). Sometimes I want to grey/fade these to make my data clearer to see. Attempting to access properties on QGIS for the VRT ...