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

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490 views

Determining gradient of road segment

I've a shapefile of roads data. It contains information about terrain of road segments, i.e., hilly, flat, undulating, etc. I want to determine gradient of every road segment. I know this might ...
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1answer
147 views

Topo To Raster executing but not creating the raster

I am using Topo to Raster by File (ArcGIS version 10.1) via arcpy on a large stream and point dataset. Arcpy runs fine and executes without issuing any error message, however it does not create the ...
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1answer
462 views

Polygonize.py: AttributeError: 'NoneType' object has no attribute 'CreateDataSource'

Given a topographic raster tif of an european country where elevations are simplyfied to either 0, either 200. How to create a polygon ? Comment: With the following polygonize.py command: ...
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1answer
33 views

How to check the value of a single pixel in QGIS?

I was wondering how to check the value of a pixel at a mouse click in QGIS (as of 2.4). In ArcGIS, the "Identify" tool does the job for both rasters and vectors. However, in QGIS, the "Identify" tool ...
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3answers
87 views

Error when Projecting Rasters using ArcPy?

Using ArcGIS 10.3 I'm receiving the dreaded 'ERROR 999999' when attempting to project a geodatabase full of rasters from WGS84_UTM_zone_10N to Nad83_BC_Environment_Albers import arcpy InRasterGDB = ...
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2answers
4k views

Reclassify raster values of 9999 to NoData, leaving all other values alone, in ArcGIS Desktop?

I have a raster in ArcGIS which has a number of cells with the values 9999, showing that the data could not be generated for that cell. I want to convert all of these 9999 values to NoData, so that ...
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1answer
27 views

How to use gdal_grid with VRT?

Hi folk's it seems to be that I'm to stupid to use gdal_grid. I' have file called dgm-10-epsg-32633.csv with equidistant samples 10x10m in this form. X,Y,Z 386700,6068670.000,.000 ...
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4answers
127 views

Fill in NoData gaps in raster using ArcGIS for Desktop?

I have a raster with gaps in it. I want to fill these in with averages of surrounding cells using ArcGIS 10.2 for Desktop. I have tried "Focal Statistics" but it averages EVERY cell and not just the ...
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2answers
29 views

QGIS dividing a raster by a polygons layer

I've got a raster image and I want to divide that raster by a polygon layer. There are just 7 polygons in the layer so i need to obtain 7 raster images as output. How can this done in QGIS?
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1answer
40 views

How to import Ordnance Survery raster layer to ArcGIS Desktop?

I have downloaded raster map data from ONS, the data has come in the form of two files... one is full of .tlw files and the other is full of .tab files... How do I import it into a raster layer to ...
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0answers
24 views

Loading ordnance survey raster ArcMap [duplicate]

I have connected to the correct folder on ArcCatalog. Only the .tif files show on my ArcCatalog tree, but the .tlw files are in that folder too. How do I create a raster layer with this data? I ...
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0answers
34 views

How to check if error due to no spatial reference of extracted raster? [closed]

I have raster file without spatial reference and I extracted my area of interest by shapefile that has spatial reference. And finally, I got extracted raster with spatial reference. can i assume ...
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1answer
36 views

Extract raster data based on a polygon's attributes

I have a land use layer with a map of the United States overlaid on top. I'd like to determine the percentage of different land uses in each state. Would the best way be to extract by mask by using ...
4
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4answers
113 views

Setting NoData for a multiband raster?

I have an RGB orthoimage that has black area instead of NoData, as pictured here: When I use the SetNull tool, it does remove the black area, however it then turns it into a grayscale orthoimage, ...
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0answers
27 views

creating composite raster tiles from multiple vector layers as new background map in QGIS

I have been patiently restyling OS Vectormap product to create a map background I'm happy with, which i want to now use as a background for a leaflet map using QGIS2leaf. I understand that performace ...
2
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4answers
432 views

Stuck in loading raster to PostGIS

I am running running Mac OS X (10.7.5), PostgreSQL (9.2) and PostGIS (2.0.2) (installed via Postgres.app). The PostGIS extension seems to work perfectly with vector and raster layers. Once I enable ...
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0answers
41 views

How to randomly generate 3 X 3 pixel window/grid size in ArcMap?

I have a raster image in ArcMap and I want to assess the accuracy of my raster image with a reference image. So, I need to randomly generate a bunch of (i.e 50) 3 X 3 pixel window/grid size from my ...
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1answer
56 views

Raster Iteration in Model Builder - Allowing a user to select the raster inputs

I have a basic model that uses Raster Iteration to process all of the rasters in a .gdb. The model allows the user to define a weighting in the GUI and then the model runs a raster calculation on each ...
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3answers
45 views

Appending interpolated or nearest raster cell value to vector point on a cell with no data?

I have been searching for a solution to this problem, but was not satisfied by the answer given in Finding nearest raster cell value based on vector point? I have some points that land on cells ...
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1answer
51 views

Export of group = multiband raster to another format not works in GRASS

I am really new in GRASS and my question is really basic but I dont realize where I am wrong. I have a set of single layers in my PERMANENT from some Landsat images (1 landsat = 7 one layer ...
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1answer
26 views

How to display symbols on a Raster in QGIS?

I have a raster file in which each cell has a numeric code which indicates that the cell is directed towards one of its eight neighbours. I am using QGIS to display each of the eight possible codes ...
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2answers
670 views

How to clip an Openlayers OSM Background to a Vector Boundary?

I'm new to QGIS. In my project i have two layers: one is my vector (city boundaries) and the other is the OSM (obtained with the plugin). How can I cut the OSM along the edges of the vector? I want to ...
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0answers
58 views

Convert GeoTIFF Raster to JSON?

So I need to convert raster data to JSON format. Is the best way to do this to convert the XML files associated with the rasters to JSON? ARC Map has a tool to convert vectors to JSON, but not ...
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2answers
42 views

Export GRASS raster as GeoTiff : nodata values exported as -nan (what happens in R?)

I am using the package raster to work with GeoTiff raster files which I expoerted from GRASS using r.out.gdal. GRASS assigned the value -nan to some raster files (type FLOAT32) for missing values. ...
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2answers
38 views

Mosaic To New Raster - Raster Cells Shift

I have wind raster datasets for the U.S. that are organized by state and I would like to merge these datasets to get one map of the whole U.S. I am new to using ArcGIS and through some research I ...
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2answers
50 views

Las dataset to raster, ground points only

I'm trying to make a raster from a las dataset. I want to only use points classified as ground points but I can't figure out how to do this. What I've tried is: Create las dataset from 2 .las files ...
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1answer
32 views

Projection coordinate system [duplicate]

I have raster image that projected by WGS1984 UTM Zone 37N. But my shapefile was Adindan UTM Zone 37N. Due to this, it doesn't overlay the same. I tried to define projection for the raster image to ...
5
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3answers
1k views

What is a simple binary raster storage format which ArcGIS can read?

I have a C++ program that manipulates raster digital elevation models. I have been using ArcGrid ASCII format for results. It is simple to code and gets the job done, but it necessitates a decimal ...
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1answer
796 views

ArcGIS 10.1 Remove (or SetNull) areas of overlapping rasters

I have one raster layer that is a site suitability layer for a county. Then I have two feature classes (one for roads and one for hydrology) that I need to remove or just set to Null from the site ...
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2answers
694 views

How to “spatially normalize” rasters of different extents to sum values of overlapping cells

How do I add rasters together that are of different spatial extents? I have many, many features that overlap over a large area (entire east coast) and I am looking to sum them "stacked" where they ...
2
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1answer
435 views

Making RasterToASCII_conversion observe environment setting for 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 ...
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1answer
81 views

Build a Raster GIS Web Application

We need to build a Web based GIS application for Raster data computation (analysis). All the maps are in form of raster images. We are failing from a week to find a proper tool which allows ...
3
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1answer
49 views

What is the replacement for 'setColorShadingAlgorithm' in QGIS 2.6?

I have been struggling with setting the colorshadingalgorithm for a raster layer in QGIS with no success for the past few days. The QGIS cookbook seems to be pretty outdated. Anyways, the code that I ...
1
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1answer
14 views

How to identify downhill cells for a dispersing frog?

I'm hoping that someone on here can help me out with a task. First, let me set the scene. I'm working on a movement/cost analysis for frogs dispersing from 135 wetlands located in Maine's mountains. ...
4
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1answer
45 views

Arcpy describe raster colormap

Does anyone know a way to use arcpy.describe to see if there is a colormap on a raster? Can't find anything in the help.
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1answer
38 views

How can I avoid a specific area of raster?

I have a raster polygon. I need to avoid certain area (another raster) from that raster. I need to avoid a watershed sub basin area that has its area on other basin also. How can I remove that basin? ...
2
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1answer
180 views

Limits to processing files from a list of rasters

I have written a script which selects all files that are within or subset by an area of interest polygon. This works fine but when the file list it's working has more than 150 records it stops ...
4
votes
1answer
951 views

Get a pixel value

How can i do this operation: I want to get a pixel value fro the satellite image (Landat, GeoTIFF, 7 bands) using qgis-python. What operators should i use? (for example in qgis's Python Console) ...
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0answers
23 views

How to visualize a C-band SAR sensor measurement

Files: \measurement\s1a-iw2-slc-vv-20141205t171642-20141205t171705-003587-0043c5-002.tiff Size is 24435, 13472 Coordinate System is `' Metadata: AREA_OR_POINT=Area TIFFTAG_DATETIME=2014:12:05 ...
4
votes
2answers
334 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. ...
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2answers
61 views

GeoServer Raster Data Sources: satellite data's contrast issue

I am trying to use my own satellite image as the basemap for a webapp, instead of OSM, Google etc imageries. In order to do that, I made a Raster Data Sources store inside my GeoServer, which is ...
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2answers
68 views

Using ArcGIS field calculator?

This field calculate returns an error, whats wrong with it? def Reclass(A): elif ( A>= 0.208113 and A <= 0.261517): return "Low" elif (A > 0.261517 and A < 0.301951): return ...
2
votes
1answer
70 views

Python and gdalwarp: change resolution of raster

I am new to GDAL and have been having some hard time figuring out how to change a raster's resolution and how to align it to another existing raster. I have come to the point where I have a raster ...
3
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1answer
58 views

Calculation of focal statistics at the edges of the region

When I use focal statistics setting the neighborhood of each processing cell to be a circle with 800m radius (map units, not number of cells), how are the statistics calculated in the edges of my ...
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1answer
20 views

How to add terrain information to an existing project in QGis 2.6? [closed]

I have created contour lines and a hillshade layers and saved it as a vector and as a GeoTiff file respectively. However, when I try to add these layers to an existing project, nothing shows up. Where ...
5
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1answer
823 views

How to get pixel size/cell size of raster layer?

After much searching, I've still not been able to figure out how to perform what seems like a simple function: I'd like to get the pixel size/cell size of a raster layer using PyQgis. Is there any ...
2
votes
1answer
39 views

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 ...
3
votes
1answer
385 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 ...
0
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1answer
43 views

set cells with specific values as NoData in afloating raster

I have a raster file which includes floating values. I need to set cells with specific values as Nodata. For Raster integer values, the setnull tool can be applied, is it any tool for floating point? ...
2
votes
1answer
502 views

Accessing PostGIS raster data using Query Layer in ArcGIS Desktop?

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 ...