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

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Calculate optimal paths between different points

How can I calculate all the possible paths between a group of points, taking into consideration the SRTM and the Slope ? I am trying to do this in ArcGIS, my dataset is a group of points (shape ...
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3answers
2k views

How can I mosaic images in ArcMap without it affecting the colour?

This is 4 images (NE, SE, NW, SW) sections of imagery. They have some overlap between them. Working with 1m 3-band orthoimagery. Different parts are sometime flown at different times/sources hence ...
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1answer
1k views

ArcMap, Make Grids and Graticules Layer example

I'm trying to use the Make Grids and Graticules Layer tool in ArcMap (have a ArcInfo license). I'm looking for a basic example like in North America. eg. 1.)Start with empty map 2.) Set data ...
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115 views

Raster display for topographic map

I'm trying to see how good a custom topographic map could be using only free data For the moment I'm just playing with the data so of course the colours are not pretty. I did some classification and ...
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229 views

Error when trying to import a raster file into a geodatabase

I am using ArcGIS 9.3.1. For some time I have had no problem importing a raster file into my geodatabase. That's recently changed and I have absolutely no idea why. Every time I try to import a raster ...
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175 views

How can I calculate raster cell area for upslope contributing area

I am new to spatial analysis, and urgently trying to follow this tutorial to generate a topographic wetness index for my area of interest: ...
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350 views

What is the correct syntax for using gdal_rasterize with a PostGIS datasource [closed]

I have a multipolygon layer in PostGIS and I would like to use gdal_rasterize to generate a raster. I cannot find the correct syntax to specify PostGIS as the data source. $ gdal_rasterize -a ...
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159 views

Use a WMS raster in ArcGIS 10 and combine with vector layer as an

I have connected to a WMS server which provided a raster images which are a LIDAR surface elevation map. http://data.gov.uk/dataset/lidar-digital-surface-model-wms I also have a vector layer which ...
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2answers
9k views

How can I join several raster files using QGIS?

I'm new to QGIS. How can I combine multiple raster layers into one layer? The raster images are of different areas with very little overlap. The goal is to bring numerous town plats into one project. ...
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1answer
241 views

Visualizing Spatial Query

I'm new to GIS applications and trying to figure out what options I have for visualizing spatial query results that combine raster and vector data using OpenLayers/GeoExt/GeoServer/PostGIS. A ...
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187 views

Manually edit cell value in DEM in Arcmap10?

Is there any chance that I could manually pick a group of cell in DEM, then edit the value of them in Arcmap 10? I know about the Aris Grid Editor for Arcmap but it requires licence and it's too ...
3
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1answer
283 views

gdal_merge.py with single band raster

I'm trying to mosaic the True Marble world imagery 250M geotiffs using gdal_merge.py though one of them doesn't have RGB bands like the rest and gdal_merge fails (same number of bands is listed as a ...
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1answer
271 views

An error in raster calculator in Arcgis

I wrote and ran this formula in raster calculator in ARCGIS. But the following error gets me into trouble. Does anyone have a suggestion to overcome this? Here is the formula I wrote and the error ...
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199 views

shortest distance between a raster and another raster

i am using arcgis 10.1 i want to calculate the shortest distance between a raster and another raster. i have a bathymetric raster and an underlying fault plane raster. for each bathy raster cell, i ...
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1answer
137 views

How to replace data in parts of raster A with the equivalent data in raster B? [duplicate]

I have the following problem: I am currently working with Landsat 5 imagery from the tropics including quiet high cloud cover. I have classified raster images with the different land use categories I ...
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96 views

Is there a tool for automated quality assurance for vector data captured on raster data?

I wonder whether is any tool(or script) in ArcGIS or QGIS which allows to make an automated quality assurance for vector data captured on raster data? vector data on binary raster:
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1answer
91 views

What's regular blocking arrangement ? (GDAL)

I am using GDAL tools to retrieve PostGiS raster. The code(command line) I am using is as follows : gdal_translate -of AAIGrid "PG:host=localhost dbname='database' user='postgres' password='admin' ...
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1answer
204 views

GMT raster (*.tiff + *.pgw) in epsg4326 shifts few kms (4326-900913-3857 problem?) [duplicate]

This seems to be an old problem with an already known solution (ie. "...stop using 900913 and start using 3857..."), but not sure whether this problem is about software versions, the raster itself or ...
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arcpy adding time to Raster Mosiac Footprint

I am trying to create a raster mosiac for use in animating data over time. The current workflow is: Create .gdb (arcpy.CreateFileGDB_management) Create Raster Mosaic ...
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1answer
65 views

Raster Clipping and Manipulation

I have two raster tiff files one is a raster that I created from 2 Foot contour lines, the other raster file is a small area that was surveyed to half a foot accuracy. My question: Is there away to ...
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3answers
344 views

How can I generate and publish raster images?

I have several hundred groups of data points (in lat/lng format). I want to generate heat maps for each group using kriging or similar interpolations and then display the generated raster images on a ...
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19 views

How to convert Rotated Polar grid raster to Non Rotated Polar Raster? [duplicate]

I have a RCM data which is in rotated Polar system , I want it to convert into non-rotated polar RCM. How can i do this things ? Please give some guidance
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4answers
2k views

Get pixel value from a raster in a xy table

I'm trying to find a way to convert a raster (in my case it's a Landsat satellite image) into a table with 3 columns which would represent: 1) x coordinates (the so called "xllcorners" in ASCII ...
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1answer
278 views

Raster as Attribute Field Error

I'm using Arc 10.1. I am creating a parcel inventory where I would like to have a photo of the property attached as an attribute and view-able with an HTML popup. I have a polygon feature class built ...
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4answers
971 views

Attempting to bring 2,300 .sid files into one raster

I've tried all of the raster tools within ArcToolbox with no luck having such a large number of files. There are about 7GBs worth of MrSID files totaling about 2,300. Most tools fail or process too ...
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2answers
1k views

Grid vs TIF vs IMG

As the title suggests both of the above three formats are raster files. In ArcGIS, apparently there's no difference between them. So what's the difference between these three formats?
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1answer
698 views

How to Calculate Utilization Distribution Overlap Index (UDOI) in ArcGIS 10?

I was wondering if any of you happen to have any information on how to calculate the Utilization Distribution Overlap Index (UDOI) in ArcGIS 10? If I understand it correctly the UDOI takes two kernel ...
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4answers
127 views

How to clip rasterdata for later processing?

My need to dwell with geographical tools is only temporary, thus I am not well versed and my question is difficult to pinpoint exactly. But here it goes: -I have about 5-10 sites, for which I need ...
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1answer
700 views

Field added to raster data is not visible in attribute table

I am new to raster data and my background is software engineering so this might be a trivial question for GIS specialists. Some raster files have attribute table but some do not. On those with ...
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1answer
146 views

Raster to polygon conversion's raster field takes only “Value”

Recently I am working with raster data and arcobjects.net. Here I find something new for me. And here some question arises in my mind. I tried to search some document that can satisfy my mind, but I ...
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1answer
160 views

value field name after raster to polygon conversion

When I perform Raster to polygon conversion using tool, sometimes it creates a field named "GRIDCODE", sometimes the field name is "grid_code". Why does it create random name of a field?
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3answers
112 views

Can a single raster pixel hold more than one value?

I am a newbie with raster data. Maybe this is a trivial question. Can a single pixel of a raster hold more than one value?
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Loading raster from PostGIS DB into QGIS: succeeded yesterday, fails now [closed]

I have a PostgreSQL(v.9.2)/Postgis(v.2.0.3) database which includes raster layers (added through raster2pgsql). To open them in QGIS (v.1.8.0-Lisboa), the "Add Postgis layer" menu will not work; ...
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392 views

Creating randomly shaped clumps of cells in a raster from seeds of 1 cell/pixel?

As my title says, I wish to "grow" clumps of cells from seeds within a raster. My base raster is full of 1's and 0's, 1's indicate land and 0's sea/NA areas. From the 1's I wish to select 60 random ...
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1answer
125 views

Problem with calculating the total cell values

aa= arcpy.RasterToNumPyArray("water_depth") sum = numpy.sum(aa) print sum -2933737 Why I am getting negative values ? In my raster there is no any negative ...
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1answer
919 views

Raster Version of Spatial Join (one to many) [duplicate]

I have two raster layers that are identical in shape (they overlap exactly) and I need to perform the raster equivalent of a Spatial Join (one to many). My files need to stay in raster format ...
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122 views

Different results from Spatial Analyst GP Tool and Python

I am writing a script that has to subtract one raster from another. The rasters I have represent 1) Parking Lots (1 = Parking Lot, 0 = not Parking Lot) and 2) a buffer around the Parking Lot (1 = ...
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1answer
234 views

Raster to vector with gaps in Landsat ETM

I need to find size of water area from a raster (jpg) using QGIS 1.8.0-Lisboa. The raster is a Landsat image with gaps of data in it. I used Polygonize, but the output file shows wrong polygon size ...
4
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1answer
339 views

Can I create a legend of a map that I had get from a WMS?

Can I create a legend of a map that I had get from a WMS? Can I create a legend of a raster map with Qgis version 1.7.4, or only with the 1.8 version?
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1answer
284 views

Extraction of raster cell values based on 'rgeos' and 'raster' buffering approaches in R

I am trying to extract cell values from a raster that lie within a certain distance from a given location (i.e. buffering). Evaluating different approaches, I found out that applying gBuffer(..., ...
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1answer
104 views

Calculating Volume of Reservoir using python and ArcMap10? [duplicate]

I have a raster file with different water depth in each cell. I am using Aster DEM so my resolution of that file is 30m by 30m. Now I want to calculate the total volume in that area by multiplying ...
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28 views

Raster attribute field error [duplicate]

I am trying to add jpegs to a raster data type attribute field. I want to this field to be managed by the file geodatabase. When I load the photos and try to save my edits it get various errors but ...
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2answers
2k views

How to extract values from rasters at location of points in R?

My question is about extracting values from rasters at the location of points. With the function extract this is very easy, and the function gives me a dataframe with the values of all the variables ...
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0answers
141 views

How to get SplineWithBarriers to work in C#

I have been having fits trying to get SplineWithBarriers to work but to no avail. My environment: Windows 7 64 bit Visual Studio 2010 Team Edition ArcMap Release Version 10.0 Product Version: ...
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1answer
361 views

Web mapping application with time slider and raster data

I need to create a web mapping application that can show raster layer of historical maps with a time slider. Basically, something like this: http://goo.gl/GYHOX I have different maps of different ...
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1answer
77 views

Grass7 - r.regression.multi and new raster

I am on the learning curve with Grass7. I managed to make r.regression.multi work, but there is one thing that would be of high interest for me: it is possible to create a new raster showing the ...
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3answers
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How to efficiently read and reclassify many rasters in R

I've been tasked to create a suitability analysis of wave conditions in the Gulf of Mexico. I have 2 thousand or so raster files that are about 8 MB each (2438 columns, 1749 rows, 1km cell size). ...
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2answers
173 views

Create Raster file in R from Matrix and latlons

I could use some advice on how to create a Raster file in R with a Matrix of datapoints and the coordinates stored in a seperate file. Both, data and coordinates come from a NetCDF file. I extracted ...
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2answers
521 views

Grass 7 / ArcGIS 9.3 - tiff to raster

Again a Grass 7 question. I have the output of a modelling run as matlab file, which I can export as tiff and load as geotiff. OK - now can I extract the data/convert this tiff into a raster proper? ...
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1answer
732 views

How to calculate volume from a raster file?

I have a raster file containing the depth of water. I need to find the volume of water using that raster file. I need to find the area of each cell and multiply with the depth. How can I do it in ...