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

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2answers
399 views

QGIS Raster Calculator: Need values to be set to 0 instead of no data

I have a landcover map with different values for the landuse options e.g. 190 for commercially used areas. Now I want to extract only these areas using the Raster Calculator with the expression ...
2
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3answers
115 views

Zonal Statistics as Table Tool

I have a slope dataset. I have a polygon shapefile with territory within the extent of the slope map. I have to calculate the real surface area of this shapefile using the zonal statistics as table ...
2
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2answers
137 views

How to draw a square from 2 coordinates?

I have a CSV file with the following output id, x min, y min, x max, y max, value 1 , 0 , 0 , 100 , 100 , 5 2 , 0, , 100 , 100 , 200 , 10 3 , 100 , 100 , 200 , 200 , 15 4 , 100 , 0 ...
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2answers
133 views

Gdal: highest and lowest point/pixel, how to get their altitudes?

Given a .tiff topographic raster image. How to get the altitudes of the highest and lowest point/pixel ?
2
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1answer
485 views

How to create attribute table for raster data?

I have raster dataset for rainfall but its not having attribute table. How can I create tabular data using the same raster file? How to join it back again to it? Software used is ArcMap 10.1.
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1answer
182 views

Efficiently check for equal adjacent values in raster calculator

I have a raster consisting of integer values in each cell. I want to check every adjacent cell in a 3x3 grid to see if any one of the adjacent cells has a value EQUAL to the center cell, and if so, ...
2
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0answers
632 views

Projecting a Raster from WGS84 to planar Equal Area to Calculate Area: How to Select the Cell Size?

I have a broad question on how to calculate the 'correct' cell size for a raster when analyzing an area not at the equator. My goal is to project a land cover raster provided in GCS WGS84 to an equal ...
2
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1answer
614 views

Create raster distance around a single point feature class

Okay, so I'm relatively new to ArcMap and I'm trying to use the Fuzzy membership for suitability test. I have a single point feature class that I want to use for this analysis. I know that in order to ...
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2answers
378 views

Can Geoserver return the raster value of a lat/lon point

I have a GeoTIFF published by Geoserver 2.2 and being used by Leaflet via WMS. How can I get Geoserver to return the raster value at a lat/long point? I'm guessing it has to do with using WCS, but ...
2
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2answers
818 views

R Raster package: write NetCDF with time dimension

I am writing a rasterbrick with multiple layers to a netcdf file using the raster package in R: writeRaster(gridfile, "Data", "CDF", overwrite=TRUE, ...
2
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4answers
529 views

Raster dataset doesn't exist error

Dataset exist and I am able to get statistics from ArcGIS python window. But it failed as a script with error: ERROR 000865: Input raster: C:\temp\ras does not exist. I have tried following ...
2
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0answers
583 views

why preview image is blank for ImageMosaicJDBC (postgis raster) layer?

I follow http://docs.geotools.org/latest/userguide/library/coverage/pgraster.html to publish a ImageMosaicJDBC layer in geoserver. the layer seems published ok and saved, but the preview of this layer ...
2
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1answer
422 views

Querying PostGIS Raster with MultiPoint

For one of my projects using PostGIS 2 I have a table with GPS tracks (igc_files). It holds records including a MULTIPOINT() column that has about 1,000 points for each record and a column that has an ...
2
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1answer
454 views

accessing postgis raster data using Query layer in ArcGIS

I tried to load raster file (jpg) into post gis using the syntax provided here "C:\Program Files (x86)\PostgreSQL\9.1\bin>raster2pgsql -I -C -e -Y -F -s 102003 -t 300x300 ras_test.tif ras_test1 | psql ...
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1answer
415 views

Recreating A Lat/Long Grid Using a Specified Formula

I'm trying to recreate the Gridded Mercury emissions 2000 (0.5 x 0.5 degree grid) designed by the Arctic Monitoring and Assessment Programme. The file is in ASCII format, but without any coordinates. ...
2
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3answers
1k views

Batch script converting and resampling orthophotos

I would like to convert more than 300 orthophotos produced at scale 1:8.000 with a pixel size of 0.8m X 0.8m from Ecw format to Tiff format and after resampling pixel values. My aim is to batch ...
2
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2answers
3k views

How to exclude missing values from raster layer?

In my raster layers the value -999 means "missing". Those points completely mess up any colormap in qgis because qgis treats them as normal values and includes them in the classification. I would ...
2
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1answer
503 views

SUM Area irregular polygons per grid cell

I have a shapefile of irregular polygons and a GRID (both as raster and polygon grid). How can I count the AREA SUM of irregular polygons per grid cell? Can use ArcGIS, QGIS or R. (Application: ...
2
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1answer
317 views

Reproject TM65 to OSGB in ArcGIS

I have a TIFF file in the TM65 (Transverse Mercator) projection, and want to convert it to the OSGB (British National Grid) projection. I'm trying to do this in ArcGIS using the Project Raster tool. ...
2
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1answer
549 views

Simple band arithmetic on GDAL virtual rasters (VRT)

I want to calculate the difference of two bands. I have the individual bands stored somewhere, but I was thinking that maybe there's a way of producing a VRT file that is the result of this ...
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2answers
2k views

Converting ASCII grid/NTF to SRTM/DEM

I want to use the Ordnance Survey Land-Form Panorama product in some software called Maperitive, which can read custom SRTM DEM files. The data is provided in the following formats: DXF [Contours] ...
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1answer
424 views

How can you make RasterToASCII_conversion observe environment setting output cell size?

I have two rasters (an ESRI grid and an IMAGINE image) that differ in projection, extent and cell size. I want to convert the IMAGINE to an ASCII, and want it to have the extent, cell size and ...
2
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1answer
306 views

Two rasters created from the same polygon have different extents?

My problem is that i am trying to export some rasters to Rockworks so that i can create a sand layer from them. Rockworks requires the grid files i use to have the exact same XY co-ordinates. So i ...
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2answers
1k views

Converting google map api coordinates into meters

How would I go about converting the results of my map bounding box into meters within javascript? For example, if I have the coordinates 51.52366625446907, -0.07467269897460938 decimal degrees, can I ...
2
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1answer
3k views

How can I compute raster pixel width and height given raster bounds, row count, and column count?

Restated, how do I convert arc degrees to meters? For example, I have an elevation data raster that has the following metadata: WEST LONGITUDE=64.97798789° E NORTH LATITUDE=33.02003415° N EAST ...
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1answer
25 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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1answer
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
63 views

Loading raster in postgis and link it with an existing table

Relatively new to PostGIS and I am currently exploring the options to make one of my PostgreSQL Tables spatial. Essentially I want to store a raster object in a table that also contains essential ...
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1answer
87 views

Export Multiple Raster Data with custom Cell Size

I Have 172 Raster, and need to change the cellsize. So I use Export Data from TOC and change the cellsize manually (example I want to change it to "3") I tried using this python script to ...
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1answer
78 views

Error on 'Extract raster values (CSV)' - Error executing algorithm 1 'Dataset' object has no attribute 'mapToPixel' See log for more details

I would like to extract raster values at some locations (point shapefile) in 'csv' format. I use 'Point Sampling Tool' and it works well for a raster file. However, I have hundred of raster files ...
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1answer
337 views

QGIS GRASS Missing Dependancy

I want to perform a view shed analysis in QGIS using GRASS 7 r.viewshed. When I double click on r.viewshed in GRASS GIS 7 commands in the processing toolbox of QGIS I get the following message: ...
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1answer
35 views

Deleting vector lines beyond image extents using QGIS?

I am using QGIS 2.2 I have one vector line layer (roads) that stretches beyond my base image (see below). I wish to have the roads "clipped/trimmed or deleted" right at the edge of the image's ...
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2answers
114 views

Retrieve Elevation from Color in Raster DEM

This might turn out to be a newbie question, and that would be because I'm fairly new to GIS work, but extensive online searching, asking associates with some basic GIS knowledge and hours in various ...
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1answer
38 views

What is a better idea for modelling a fault plane than as TIN? [duplicate]

I am working on a project which runs on ArcGIS platform using VB.NET. It is to model a sub-surface fault plane (currently a plane rectangular model with some dip) and then to find required distances ...
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2answers
306 views

Replacing raster values in one raster with another raster in QGIS … how to?

I have a raster (DEM) and want to replace a few cell's values with the values from another raster in QGIS. I would have done this with the "over" tool in the raster calculator in ArcGIS. Specifics: ...
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0answers
43 views

MapServer: UV_ANGLE not calculated correctly?

I'm following this example given on the MapServer website. But the angle of the raster is incorrect: The data is my grib files is correct, and should not yield these perfect opposite directions. ...
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1answer
149 views

Unexpected output when using gdal_rasterize

Ok, I used the following code for converting my layer into raster format but I get a tif file that is completely black or white... from osgeo import gdal, ogr # Define pixel_size and NoData value ...
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1answer
47 views

How to export a IDW raster while keeping the search radius data

I want to export my IDW rasters that I made in ArcGIS to QGIS, however when I export my raster, the values are there but are no longer displayed. They are stored within each cell and are not ...
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0answers
265 views

TIN to Raster Tool, output elevations are 3.40282e+038 and -3.40282e+038, tried calculate statistics didn't work

I have an input TIN file that I created using Create TIN. The elevations are all correct. When I convert the TIN to Raster using the tool, my output elevations are 3.40282e+038 and -3.40282e+038 ...
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2answers
166 views

Copy rasters slow, increases file size

I have a folder with ~1200 aerial photos in both jp2 and tif format, of which I need about 380. I wrote a python script to get the names of the files I need, which works fine. But when the script ...
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1answer
1k views

How to Build Raster Attribute Table from .tif with pixel type of float or double?

I have a raster with the extension .tif. It's a subset of 87x87 pixel with values from some 6,66 to -4,27. If I right click on it there is no Attribute Table available. However, I can change the ...
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0answers
124 views

Touch up tool for rasters?

I was wondering if it were at all possible to manipulate/massage rasters (eg Geotiff) using Qgis plugins or Grass?? By manipulate, I mean manually smooth off interpolation artefacts, blended surface ...
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1answer
498 views

Why does CON statement give ERROR 010240: Could not save raster dataset to (value) with output format GRID?

I am receiving the following error when trying to run the following code: import arcpy from arcpy import env from arcpy.sa import * arcpy.CheckOutExtension = "Spatial" env.workspace = ...
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1answer
233 views

“dataset does not exist or is not supported” using large GRID raster

I am trying my hand at arcpy for the first time to create a conditional raster from a set of threshold values. I have 3 large GRID format rasters (mos_zb3, mos_zb4, pca_finb2) I am trying to feed into ...
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2answers
249 views

Read layer symbology class color with ArcPy

I am using ArcPy within ArcGIS 10.1 and attempting to read symbology from a *.lyr file created by a raster dataset within ArcMap. My goal is to be able read out the RGB (color) values assigned to the ...
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2answers
697 views

How do I import OS raster tiles into QGIS at the correct scale?

I have some tiles of OS raster mapping and their associated TFW georeferencing files. The GR files are in the same folder as the raster data and have the same names, ie TQ21.tif/TQ21.tfw. In QGIS ...
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1answer
182 views

Can't view PostGIS rasters after changing schemas

I have loaded a few rasters into the Public schema of a PostGIS 2.0 database. Using the db manager in QGIS 1.8.0 I can add the rasters to the map canvas. After moving the rasters to another schema in ...
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1answer
268 views

ESRI Raster Remap with Decimals

I have a requirement where the user would like to see the output value in a raster as a decimal. The user will input a series of ranges with a cost associated to them. For instance 0-5, 1.20 ...
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5answers
312 views

Create world file from kml

I have a KML file for a NASA image. I want to create a world file from it so I can use the image in say QGIS. Is it possible to extract the key info (bounding coordinates) from the KML? It seems to be ...
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3answers
524 views

Round Raster to next higher or lower int

I am using ArcGIS 10.1. I am searching for a solution to calculate a raster. The values are like: 0.2 0.6 5.3 i.e. How can I now get 0.2 as 0 and 0.6 to 1 and 5.3 to 5? In the end integer numbers. ...