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

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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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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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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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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 ...
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1answer
451 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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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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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
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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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189 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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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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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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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
664 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
715 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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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 ...
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1answer
497 views

Creating field with specified slope projecting from 3D polygon?

I am 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 ...
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186 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
614 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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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
449 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 ...
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1answer
5k 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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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' ...
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1answer
402 views

Perform Multiply (Times) Function on Several Reclassified Rasters Using Python

I have several reclassified rasters (0 = snow cover, 1 = no snow) and I would like to use the multiply function on all rasters that have the same spatial extent. In ArcGIS 10 this function can be ...
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1answer
331 views

Search Raster Files from Folder that Have Same Spatial Coordinates Using Python

I have approximately 700 raster files in a single folder and I need to find files that have the same spatial extent and copy to a different folder. The raster files measure daily snow cover and ...
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How to perform Raster Reclassification in QGIS?

Is there a way to do reclassify a raster image to Qgis? In Arcgis you can do that in Spatial analyst Tools→Reclass→Reclassify Any ideas?
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3answers
370 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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2answers
7k views

Manipulate .asc files in qgis

I have an .asc file and I want to import in QGIS. The standard way to open it is from "add Raster layer" ("import Raster Layer"), there is another way? I know is strange that ask but I need it. And I ...
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106 views

How can I identify the pixel with the maximum value in a grid? [duplicate]

Possible Duplicate: How to find the locations of the highest values in a raster? How can I identify the pixel with the maximum value in a grid and get its coordinates? Any VBA code please?
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Multiple Conditional Reclassification - ArcGIS

This is a question out of curiosity rather than a problem as I am not the most experienced with raster datasets and I wonder if there is a better solution to my current approach. I am trying create a ...
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How to smooth/interpolate a raster in python using GDAL?

This is my first post so please feel free to critique where necessary. Background: I am developing in Python and using GDAL from OSGEO to manipulate and interact with rasters and shapefiles. ...
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Export georeferenced image overlay from KML?

How might one export image(s) from image overlays in a KML file to a standard geo-referenced raster format like geotiff? Use case: NASA's Earth Observatory has a time series of the changing Athabasca ...
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257 views

Looking for US National Grid to Lon/Lat Converter in Python, C, or C++

I see here that there is Fortran source code for going from USNG to lon/lat: http://www.ngs.noaa.gov/PC_PROD/USNG/ Is there some python or C/C++ code that does the same? My understanding that this ...
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Raster legend in R: how to colour specific values?

I have an elevation model plotted in R r <- raster("example.dem") plot(r, col = topo.colors(20)) Some of the values are below sea level (0), and I'd like to have those display in red. How can ...
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What resampling technique should be used when projecting aerial photos?

I'm doing some time-intensive projecting of aerial photos, and I'm curious - what resampling technique is best to use on aerial photos? In ArcMap, my options are NEAREST, BILINEAR, CUBIC, and ...
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Extract the area of a DEM above where 60% of the region lies?

I have a DEM of a mountainous region. I'd like to extract the areas of the DEM above which 60% of the total DEM area lies. So, essentially I'd like to extract the areas representing upper portions of ...
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1answer
1k views

Random sampling of raster using R

Is there a straightforward way of randomly sampling a raster so that the output of the process is a raster? I'm using an example that I found on the r-sig-geo list and I have also tried the ...
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1answer
757 views

Method to shade or overlay a raster map to reflect time of day and ambient light

I have a daytime raster of my study area. I have 20+ counters in the study area that count "stuff" with a timestamp. Using PyEphem I determined the type of ambient light for each collected data ...
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Can I overlay layers in Dealul Piscului 1970 and WGS84 in QGIS?

I have a 10 Gb ECW file (mosaic of a whole county) that is in Oblique Stereographic projection with Datum: Dealul Piscului 1970. The problem was that no matter the Default CRS for new project was, ...
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1answer
357 views

ArcPy replaceDataSource to an SDE raster catalog error

New to Python! I'm trying to re-path a multitude of rasters currently the workspace is a folder, the intended workspace is a raster catalog in an SDE database - using the replaceDataSource method I'm ...
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487 views

How to fix a raster with wrong Eastings?

I get an error when trying to warp a tif file in QGIS: ERROR 1: Too many points (35721 out of 35721) failed to transform, unable to compute output bounds. I am using QGIS 1.7.0 Wroclaw with gdal ...
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728 views

Dealing with bridges and tunnels when modeling raster least cost paths?

I'm currently using ArcGIS 10 Spatial Analyst's Cost Path tool to model pedestrian routes. I have sidewalks, fences, buildings and a ton of pedestrian scale features, all combined into a cost surface ...
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381 views

Reading multiple grid data with Python and ModelBuilder

How can I read grid data (3 or 5 sources of grids) like slope, soil, cover, etc.? My goal is to build a simulator based on multiple grid data for harvesting decisions.
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Simplify Raster Contours ArcGIS 10

Does anybody know a way to simplify a number of contour polylines derived from a raster dataset? I need to generate a map that shows contour polylines at relatively small scale. With the contour ...
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2answers
461 views

How to add different sized rasters in GDAL so the result is only in the intersected region

I'm writing a Python method that adds two rasters and generates a single raster output. For reasons beyond my control, the extents of the input rasters are different, but they do overlap. Is it ...
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795 views

Tools/processes that avoid the need for raster to vector converstion?

A "brute force" method of solving GIS problems that involve acquiring values from raster cells and storing them on spatially overlapping vector features is to first convert the raster to a vector. The ...
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1answer
902 views

Workaround for Raster data input in ArcGIS Server Geoprocessing Service

UPDATE I have accomplished the Python script, but only tested in desktop environment, i.e. ArcMap. #Import ArcPy site package module import arcpy from arcpy import env from arcpy import Extent from ...