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

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978 views

GDAL Clipping (hack)

I am trying to use the python script from http://www.sparkgeo.com/labs/2010/07/07/gdal-clipping-hack/ to clip a raster based on many shapefiles. The script is using a mysql database an i would like to ...
9
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1answer
396 views

Efficient raster sampling of billions of polygons (bounding boxes)

How can a raster be computed efficiently (in Python), given a set consisting of billions of bounding boxes (read sequentially from a file), and given that the raster values for each cell should give ...
2
votes
1answer
225 views

Why is GRASS not thinning a terraflow raster properly?

I want to convert a raster map encoding directional flows (the output of r.terraflow) to a vector map. I'm using r.thin to process the output. It terminates successfully with 0 pixels removed during ...
3
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1answer
406 views

Looking for Mid-Holocene (~6000 BP) bioclim dataset

I am trying to obtain climate data for the Mid-Holocene (~6000 BP), preferably in the bioclim (19 bioclimatic variables) raster format. The worldclim.org website lists this dataset based on the CCSM ...
2
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1answer
2k views

Why is ArcGIS crashing when I try to load .adf raster data?

I am pretty new to GIS, so forgive me if this is a stupid question. I downloaded a bunch of land cover files from USGS seamless warehouse of Florida. Every time I try to 1) view the .adf file (which ...
3
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1answer
372 views

ArcSDE - How to edit mosaic dataset

I have a mosaic dataset (Raster) in an SDE database. As expected, when I click start editing, ArcMap says that I have to do "Register as Versioned" before, but I can't have a mosaic dataset in a ...
2
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1answer
707 views

Select vectors overlapping a raster

I have a raster layer with travel times from a specified point in my city's downtown. What I'd like to do is select all of the census blocks that lie at least partially within 45 minutes of downtown ...
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3answers
469 views

Adding .bil raster file to GeoServer and viewing it on GeoServer or GeoNode

Ok so my Boss gave me this job. Uptil now i was working on ESRI products and this is my first venture into OpenGEO. He has given me a link, http://www.worldclim.org/current, from where i need to use ...
6
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0answers
333 views

How to store Large Raster Images of Equipotential Surface Generation Using Monte Carlo Simulation?

I have a large (1GB+) raster that I am using as the base for the generation of an equipotential surface. This is to assess the accuracy of DEMs derived from another source. In situ observation is ...
2
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1answer
1k views

QGIS and satellite images band combination

When I add a satellite images as a raster in QGIS: 1. Why the image is changed, it looks like it has only one band?; 2. where is a tool for band combination? Thanks!
9
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7answers
18k views

How to get X Y coordinates and cell value of each pixel in a raster using Python?

I’m really new to Python and I would like to know whether there is a quick method to get cell values of a raster pixel by pixel and the coordinates (map X Y coordinate of centre of each pixel) using ...
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0answers
886 views

ArcGIS 10 - disappearing rasters?

From time to time it happens to me that rasters disappear at certain zoom level in ArcMap, or only some parts of the raster (strips) show up. I'm working on WinXP, ArcGIS / ArcView 10, Sp2, rasters ...
3
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1answer
169 views

rgb2pct.py increases size of file 20 fold!

I wanted to reduce the number of bands of a tif file from 3 to 1... I used this command rgb2pct.py -n 256 fnp_braunschweig.tif fnp_bs.tif and it increased the size from 31mb to 778mb I actually ...
6
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2answers
3k views

Using individual bands from a multi-band image in ArcGIS 10 raster calculator

I'm trying to use individual bands from a multi-band TM image (IMG file) within the raster calculator in ArcGIS 10 (SP2/3). I can add individual bands to my MXD, but raster calculator will only use ...
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0answers
254 views

how to buffer a raster cell using Visual Basic ArcObjects in ArcMap [closed]

I am new in visual basic, I have a question about creating a buffer zone based on a raster layer. I have a raster layer named "Value_Raster", I have a textbox in the userform, I also create a tool ...
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vote
1answer
798 views

1-band raster colour table workaround in QGIS

Does anyone know what the workarounds are for the 1-band raster colour table plugin in QGIS? Currently I find it will run once, then crash on the second iteration. The workaround I use is to delete ...
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0answers
192 views

How can I ignore NoData values in map algebra? [duplicate]

I need a way to exclude NoData from calculations. I don't want any NoData cells from any of the rasters to be used in pick or con statements.
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2answers
2k views

How to read this GRIB data [closed]

on this open FTP server (ftp://ftpdatos.aemet.es/modelos_numericos/hirlam005_peninsula/) you can find HIRLAM models from the Spanish meteorological service. The documentation in the LEEME files (in ...
8
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3answers
2k views

Poor image quality of raster pyramid files in ArcGIS Desktop (no anti-aliasing)?

There are several GeoTIFF files (size ~7000x7000 px) which I try to open in ArcGIS Desktop 10.0. I have already created raster pyramids for them (.ovr files) using geoprocessing tool but their quality ...
7
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2answers
1k views

How to animate raster time series using open-source GIS?

I have a bunch of rasters taken about 10 minutes apart, and I have a nice QGIS project that produces pretty enough maps of them. I'm wondering if there's a way to animate this raster series, with a ...
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2answers
2k views

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, ...
2
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1answer
582 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
57 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
131 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 ...
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1answer
1k 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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votes
2answers
2k views

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
10k 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
2k views

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 ...
2
votes
2answers
450 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 ...
9
votes
3answers
956 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 ...
10
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2answers
3k 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 ...
7
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2answers
529 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 ...
4
votes
3answers
484 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 ...
1
vote
1answer
755 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 ...
4
votes
2answers
611 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
votes
1answer
560 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: ...
4
votes
1answer
559 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 ########### ...
3
votes
1answer
600 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 ...
2
votes
3answers
2k views

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
7k 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?
1
vote
1answer
3k 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 ...
3
votes
2answers
2k views

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 ...
2
votes
3answers
3k views

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 ...
2
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1answer
433 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
63 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
98 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 ...
2
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0answers
215 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
4k 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 ...
11
votes
3answers
1k 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
497 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 ...