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

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Using SearchCursor to access & export values in a raster table

I am desperately trying to export the values in a raster table to a .txt file. I've seen some other folk post about this, but for some reason can't get the code to work in my case. I have a raster, ...
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1answer
487 views

Spatial Analyst tool Look up but in ArcView3.2

Is there any option how to do a Spatial Analyst tool "Look up" operation from ArcGIS 10 in ArcView 3.2? I have a grid with attributes and need to "extract" values from the table field (values from ...
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0answers
47 views

How to recreate the 'standard deviation' option for a raster layer in Mapserver?

In mapserver is there any way to recreate the 'standard deviation' option available in Arc's symbology for a stretched raster layer?
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3answers
126 views

How to add a float or integer number (i.e 255) to a raster layer?

Is there any code to add a float or integer value with a raster layer? I can easily do mathematical operations between two raster data. But I am unable to do the same between float or integer number ...
4
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1answer
941 views

Why does QGIS's Clipper tell me “Computed -srcwin falls outside raster size” and how do I address it?

I'm trying to clip a heightmap to a small area that I'm interested in. When I attempt to use Raster > Extraction > Clipper I get an error dialog with the message ""Computed -srcwin falls outside ...
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2answers
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creating a raster of the residuals of a regression between two rasters

I am trying to create a raster of the residuals of a regression between two rasters. i.e. I would like to carry out a regression of one raster against another of the same extent and plot the residual ...
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2answers
4k views

How can I convert data in the form of lat, lon, value into a raster file using R?

I have a data set of values over a km grid in the continental U.S. The columns are "latitude", "longitude", and "observation", e.g.: "lat" "lon" "yield" 25.567 -120.347 3.6 25.832 ...
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1answer
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How to create a single depth contour line from a bathymetric raster?

I have bathymetric data (raster form) that I'm trying to tease out specific depth contours. For example, I would like to "create" the 150-m depth contour from the bathymetric data in the Gulf of ...
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2answers
342 views

Mapinfo, (or other?) Interpolation of lat/long and finding minimum in a region

I have a series of lat/long coordinates, each with a corresponding Z value. Each coordinate is spaced roughly 40km apart (this is stored as a MapInfo table of points). What I'd like to do is to ...
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3answers
629 views

Creating raster by randomly choosing cell value from multiple overlapping rasters?

I'm using ArcGIS Desktop 10 with its Spatial Analyst extension. How do I combine multiple rasters into one, always choosing randomly from the values of overlapping cells? I have an image that may ...
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2answers
2k views

Intersecting a raster with a polygon using PostGIS - artefact error

I'm using PostGIS2.0 to do some raster/polygon intersections. I'm having difficulty understanding which operation I should use, and what the quickest way of performing this is. My problem is as ...
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2answers
367 views

Confidence interval from raster data

I have raster data that represents a probability distribution, i.e. each cell has a probability value (in my case the probability that an animal may be found in the cell), and all the cells add up to ...
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3answers
339 views

Export from GIS to static html clickable hypermap?

What plugins or tools are available to conveniently export a GIS view to a html clickable hypermap? Since 2005 or so we use a commerial plugin for ArcGIS, We have a working example of the output ...
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1answer
610 views

Help with technique to create contours from ASTER DEM in Phnom Penh, Cambodia

I have the ASTER version 2 DEM of Cambodia. I want to use it to create 1m contours of Phnom Penh, Cambodia. If anyone has this already please let me know. Now, onto the problems: I am using ArcGIS ...
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2answers
510 views

How to generate an image from WKT?

I am looking to programatically generate an image from a WKT string (or any other common format, such as WKB or SQL Spatial geography). Are there any existing libraries that allow for this? I am ...
2
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1answer
445 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: ...
3
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1answer
398 views

How can I apply a raster style to multiple layers using MapServer?

I'm using Mapserver to display a raster in browser using a WMS request from OpenLayers. At the moment I have just one raster, and used the following method of styling it: MAP ########### ...
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1answer
485 views

turning multiple vector layers into one raster in arcgis 9.3.1

I want to make a raster out of the multitier view I have in ArcMap 9.3.1 . The layers in my ArcMap come from several datasets. I know there is a 'Feature to Raster' tool, but it converts one layer at ...
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3answers
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How to publish ECW images to ArcGIS Server?

When I am going to publish mxd (containging image.ecw) to ArcGIS Server, the following error appears: Confiquration image.ecw. MapServer can not be started. Server Object instance creation ...
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3answers
4k views

How to add Raster legends in QGIS map composer?

Is there a plugin or method to add legends for raster layers (with a custom colourmap) as an item in the print composer?
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1answer
2k views

Loading a raster using Openlayers and Mapserver

I'm trying to load a raster into my browser using Openlayers. I can examine my WMS raster layer using OpenJump, but I'm not able to get it to load into my browser. My mapfile is as follows: MAP ...
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2answers
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How to show “First Vertical Derivative of the Magnetic Field” survey data on a map?

I will be given a magnetic survey raster and I am being asked to display this on a map as a "First Vertical Derivative of the Magnetic Field". I've done this before with a different older dataset but ...
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3answers
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How to convert raster data into regularly sampled points?

I am wondering if there's another way to convert raster data (ex: DEM) into regularly sampled points. I've used Raster to Point under ArcToolbox previously, but if the raster data is huge, that's a ...
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1answer
351 views

How can I, in a general way, rescale a raster in ArcGIS Model Builder

What I want to do is rescale a few rasters from whatever they are now (i.e., values between -99 and +1000 OR -256 - +256 OR 0 - 3.23) to a normalised value (i.e. values between 0 and 1). I would ...
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0answers
58 views

Guide for esriRasterOpCode

I'm building dynamic cartographic symbols to display inside ArcMap, but they are displaying "wrong". Is there a guide somewhere that will show what raster op code does? I mean, not only show, but ...
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1answer
90 views

Will a WMS handle RPF image scale?

When serving RPF imagery (Raster Product Format) from a WMS, will the WMS handle which layer should be on top? For example, let's say I request layer X and layer Y in some bounding box, and layer X ...
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202 views

ArcObjects .NET 9.3 upgrade to 10 breaks IRasterDataset.Copy(…) code

I have to upgrade an application from ArcObjects 9.3 (C# .NET) to 10. Unfortunately, there seems to be some incompatibility regarding the IRasterDataset.Copy method. The following code worked fine in ...
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4answers
3k views

making a mask with arcmap 10

I have a grid layer and a shapefile representing a closed boundary. I need to make a new grid as big as my current grid but with values equal 1 inside the closed boundary shapefile and -999 for grids ...
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3answers
861 views

Web mapping software for a huge raster time series?

I'm an ArcGIS Desktop user who is stepping into the world of web mapping for the first time. Following advice I found here on GIS.SE, I started with the free tutorials from OpenGeo. However, I ...
3
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1answer
416 views

Change raster value for an area based on a class of another raster

I would like to change all raster values in raster A that fall into the locations of category/class 1 of raster B. Here, some more details. I did a calculation on a DEM resulting in different ...
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2answers
431 views

What is the correct way to convert a USGS Orthoimage from WorldImage format to tiled GeoTiff for GeoServer?

USGS provides different resolution orthoimage quadrangles in the WorldImage format (*.tif with an accompanying *.tfw world file). Some of these quadrangles can be used by GeoServer (2.1.0 - 2.1.2) by ...
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5answers
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Is Hillshade option in ArcMap rubbish or is it me?

Here is a pretty pic of the raster I am using - with no effects applied - just the color ramp and historgram adjusted to show out all the relief - all be it in a very 2D way! I have a raster layer ...
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2answers
826 views

ImageMagick's convert program changes PNG file format so that color/alpha info doesn't survive GDAL

It appears that ImageMagick's convert program changes something in my PNG file that causes GDAL processing to mess up the color and/or transparency bands. My original PNG file gets processed ...
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2answers
178 views

Vectorize cell boundaries in GRASS

I need to vectorize the cell boundaries of a raster map and I have forgotten how to do this. For instance, if I have a raster map of a region that is just map=1 with a cell size of 500m, I would ...
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2answers
979 views

Where are imported Mosaic Dataset images stored on ArcSDE server?

I am trying to learn more about Mosaic Datasets and specifically how they interact with ArcSDE (SQL Server 2008). I read in How raster data is stored in a geodatabase that "...In the case of the ...
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0answers
300 views

ValueError when reading a raster band as a numpy array

Here's the problem shown in Python shell: In [32]: from osgeo import gdal In [33]: geotiff = '/Users/calvin/work/luc/proj_public/media/GLO ...
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4answers
7k views

Loading a raster into a PostGIS 2.0 database on Windows

I'm trying to figure out how to load a raster into a PostGIS2.0 database (I have asked previous questions on this topic here and here). I am trying to use the raster2pgsql.exe program provided with ...
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2answers
604 views

Extract all pixels of given RGB value and render as MultiPolygons

Given a geotiff image with a colortable in it, what is the easiest way to extract each color as its own "layer or shapefile or multipolygon object"? Specifically, I am looking for a programmatic ...
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4answers
650 views

MapServer rendering at the lowest zoom levels

I am developing a web mapping application based on OpenLayers and using a WMS layer from MapServer (the source data for this layer is stored in PostGIS database) and I am facing the following problem: ...
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0answers
98 views

How to delete classes that cover only a small area? [duplicate]

I want to delete pixels that have a small area of classifying in raster and vector images in ArcGis software.
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1answer
2k views

Loading a raster using QGIS into a PostGIS2.0 enabled database

Following on from my attempt to install a postgresql 9.1 db with postgis 2.0 on windows 7, I am trying to figure out how to load a raster. I have successfully loaded a shapefile, and am trying to do ...
5
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1answer
424 views

How to create a field with a specified slope projecting from a 3D polygon

Im trying to figure out how to create a elevation raster from a known location (3D polygon) that projects at a specified slope (1%) for a specified distance(1-2 km). Does anyone have any idea how to ...
4
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2answers
168 views

Is there a simple way to detect what generation a MrSID file is?

I just found out there are a few types of MrSID files - generations MG2,MG3,MG4. As I have a user which uses Bentley Microstation V8 and apparently can see only some of the generations (and thus I ...
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1answer
539 views

How to convert dbf to raster the short way?

I have got a dbf file and i want make it to raster file but shor way, Look at my long way, 1- First i add my dbf file 2- and i create tin http://i1211.photobucket.com/albums/cc421/mtnkou/2.jpg 3- ...
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How to crop a Raster by Region?

I have created a grid using the point density function in VM. I would like to crop this image to a region created from buffering a polyline feature set. Is this possible? Alternatively I have used the ...
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2answers
918 views

How to convert from GeoTIFF to PNG/JPG and Web Mercator in Java?

I'd like to convert raster image from (geo)tiff to an png/jpg and afterwards if it is necessary ... I'd like to convert the coordinates with help of EPSG-Codes to the OSM/Google Projection(EPSG: ...
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1answer
384 views

Is there any plugin for QGIS to calibrate contrast and brightness of a raster layer?

I frequently need to deal with the contrast and brightness of raster layers in QGIS and I miss the tools in ArcGIS for this task. Should there be a plugin already developed for QGIS? If there is, ...
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2answers
3k views

How to create a color ramp in ArcGIS10 where the zero value is represented by white?

I have a simple problem which (to me) seems to be difficult to solve in ArcGIS. The map I plot is a GeoTIFF with emission data. I use a default algorithmic color ramp (rainbow) to do so. Now I would ...
7
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1answer
4k views

Converting a polygon into a raster using R

I'm trying to convert a shapefile into a raster within R. My approach is to read in the raster as follows: library(rgdal) # Loads SP package by default demo <- readOGR('F:/data/', 'shapefile') # ...
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2answers
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How to build an artificial 'dam' across a river?

I have a DEM. Created all files related to watershed including accumulation, direction, streams etc... I'm stuck creating a dam. I request you to please let me know how to build an artificial 'dam' ...