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

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1answer
182 views

GeoServer: Link meta data to raster image?

I want to use the OpenGeo Suite to publish different sets of raster imagery with associated data. Doing this with vectorial data works fine: Setup the data base in postGIS: import the vectorial data,...
2
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0answers
60 views

How to load a raster from in-memory bitmap (not from file) into PostgreSQL

I have a bitmap in memory that I would like to load as a raster to PostgreSQL. An unfavorable option is saving the bitmap to file and then use raster2pgsql, but as we have several cameras that ...
4
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2answers
812 views

scratch files left behind by arcpy.sa.Con

I have a Con() statement that creates two "extra" scratch files during it's processing, but that do not get cleaned up once the operation is over and the output is saved. r=arcpy.sa.Con(elv, ...
3
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2answers
748 views

Need to get the minimum cell size of collection of rasters

I have the following model in ModelBuilder: Get Raster Properties looks like this . . . I need to find the minimum cell size value to use as output. Any ideas on what tool I should use to replace ...
4
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1answer
346 views

How to implement multiprocessing with multiple geoprocesses?

I am relatively new to Python and thought I would give a stab at multiprocessing. I have a script that runs well in IDLE or as an ArcMap toolbox script. After perusing these forums and docs.python, I ...
2
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2answers
2k views

Arcmap 10 restrict Flow Accumulation

I am working with the Flow Accumulation tool in ArcMap 10's spatial analyst hydrology tools. This tool calculates the total number of raster cells that flow into a given cell. However, for my purposes,...
2
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1answer
210 views

Is JAI really that usefull for raster images on Geoserver?

I've been going back and forth with JAI for quite a while by now. I've never been really impressed with it to be honest. Is it really all that jazz that I hear people talk about? The problem with JAI ...
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1answer
96 views

Counting points in a raster

Is there a way to select points in a raster dataset by raster classification? I have a floating point raster created from the points, classified into 4 ranges by standard deviation. I want to find out ...
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1answer
455 views

Export ArcGIS Model to Python - Iterate Rasters, Collect Values, Calculate Values

I want to batch process a large number of raster files, calculate some values and properties and export these to a .csv or .xls. I managed to get a good working model that does this perfectly. ...
1
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2answers
774 views

How to write raster field values into attribute table using ArcPy?

Is it possible to use ArcPy (10 or 10.1 )to write raster field types into a featureclass? either SDE or filegeodatabase?. I'm hoping to use arcpy as means of automating the process of adding rasters ...
6
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1answer
3k views

Raster spplot legend: how to add a title beside it

After studying for a while how to create a chart from a raster object, I got almost everything I needed except to add a title to spplot's legend. What I tried: to use mtext("XXX (m)", side=4), ...
2
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2answers
92 views

Webmapping option that allows rasters?

I'm trying to create an introductory GIS course that will involve an ideally simple web mapping component. I was underwhelmed that ArcGIS online doesn't support rasters, and surprised that MangoMap ...
0
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1answer
297 views

It seems there is a bug in St_Clip function of PostGIS

The code I am using for clip feature is : raster ST_Clip(raster rast, geometry geom, double precision[] nodataval=NULL, boolean crop=true); I tried clip a shape depends on the polygon from the ...
0
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0answers
465 views

How can I calculate raster cell area for upslope contributing area

I am new to spatial analysis, and trying to follow this tutorial to generate a topographic wetness index for my area of interest: http://gracilis.carleton.ca/CUOSGwiki/index.php/...
3
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0answers
234 views

QGIS - Android, loading a .tif file

I have a .tif file I would like to use as my base map on the Android version of QGIS. However, when I try and load it as a raster layer, it states that this is not a correct raster source. Is there a ...
0
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2answers
119 views

GDAL clips raster at wrong position

I try to clip raster data with GDAL (in fact I am using QGis, which produces me a command line for GDAL) The raster has been transfored to EPSG:3857, which is also the projection of the shape file ...
6
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0answers
672 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 ...
2
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1answer
259 views

How to smooth a raster in a rectangular fashion using gaussian blur?

How do I adjust the code for the Gaussian Blur posted in the thread: What raster smoothing/generalization tools are available? to retain the resolution/gradients in the y direction and blur only ...
0
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1answer
400 views

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

I have connected to a WMS server which provides raster images, more specifically, LIDAR surface elevation maps. I also have a vector layer which contains the outline of buildings. I would like to ...
0
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0answers
977 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 ...
2
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1answer
1k views

Why does copy convert my Tiff raster value range?

Recently I have worked with some raster dataset. And I found there are different kind of raster dataset. Till now I have worked with grid type raster dataset and my add-in works fine with this type. ...
3
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1answer
755 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 ...
3
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1answer
2k views

ArcGIS - Export raster keep color scheme

I have a *.flt raster loaded in ArcMap. I would like to export this raster as a georeferenced tiff file keeping the color scheme I have provided in the symbology. I right click in TOC, Export Data ...
2
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2answers
1k views

Stripping spatial reference

I am creating an exercise for remote sensing students and would like to take an existing raster and remove the spatial reference from the file so that the students can practice using another image to ...
3
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1answer
466 views

how to rename the band-names of a layer stack?

I created a layer stack of 20 images (all GTiff-files) using the gdal_merge tool in QGIS, available at: raster > miscellaneous > merge The result is a GTiff layer stack of the 20 images, but ...
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1answer
305 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 ...
3
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1answer
1k views

Problem about converting raster to polyline and calculating total length

I have raster file of line segment. I need to convert it to line and get the distance of that line. How can i do using Python and ArcGIS 10? I have tried with GIS tools Convert Raster to Polyline but ...
0
votes
1answer
137 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' ...
0
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1answer
90 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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5answers
655 views

Create world file from kml

I have a KML file for a NASA image. I want to create a world file from it so I can use the image in say QGIS. Is it possible to extract the key info (bounding coordinates) from the KML? It seems to be ...
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2answers
3k views

What to do when raster cell size is larger than zonal vector feature in order to collect statistics?

I am trying to extract the mean cell values for a raster dataset based on a survey grid polygon feature using ArcINFO 10.1. The cell size of the raster dataset is about 4 times the size of the survey ...
3
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2answers
6k views

How to convert .geotiff --> .tiff?

How to convert .geotiff files to .tiff files (ordinary plain images)? Basically, I have cropped the image to a rectangle of interest and knowing its left-lower location and having chosen the pixel ...
4
votes
1answer
681 views

mosaic raster to file geodatabase yields missing raster sections

Since upgrading to ArcGIS 10.1 (SP 1) from 10.0, I've been encountering an issue when running the arcpy.MosaicToNewRaster_management() tool with output to a file geodatabase. I'm principally working ...
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4answers
9k 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 terms);...
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0answers
21 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
2
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1answer
1k views

ArcMap 10.1 - Tabulate Area tool “doubling up” for Overlapping Buffer Zones

This question is related to a previous question I asked: Raster Version of Spatial Join (one to many) I used the Tabulate Area tool to crosstabulate values between an overlapping "buffrast" raster (...
18
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2answers
15k views

Clipping a raster in R

I am building a map for the northeastern U.S.A. The map background needs to be either an altitude map or a mean annual temperature map. I have two rasters from Worldclim.org which give me these ...
0
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1answer
515 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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1answer
367 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 ...
0
votes
1answer
2k 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 ...
3
votes
3answers
196 views

Can a single raster pixel hold more than one value?

Can a single pixel of a raster hold more than one value?
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0answers
3k views

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; ...
4
votes
3answers
5k views

How can I reclassify a raster to floating point values?

I have a raster of landuse values that I need to reclassify into pollution concentration values. I have the pollution values in a separate table. They are decimal values (ex. 0.0056), and my landuse ...
7
votes
2answers
1k views

How to generate TFW files for a list of images?

I have a few digital images that are not georeferenced. E.g.: Img01.tif Img02.tif ... Img99.tif On the other hand, I have a text file, which contains georeferencing information for these ...
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0answers
35 views

Assign value to raster cells within masked area [duplicate]

The answer I previously received for this question did not solve my problem...please keep in mind that I am a GIS beginner, and it's quite likely that I carried out the proposed solution (using ...
2
votes
1answer
577 views

How to read XY, get raster value and then update field?

I've written a script to run through a point layer, using the SearchCursor in the data access module and then read the XY values. Within the with statement, I then use GetCellValue to get the ...
1
vote
1answer
256 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 depth.
3
votes
2answers
437 views

Tabulate Area crashes Python and ArcGIS

I have a script that runs Tabulate Area on a single feature class multiple times with different rasters. In total Tabulate Area runs 5 times. 2 of the input rasters are provided as arguments to the ...
3
votes
1answer
3k 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 ...
2
votes
0answers
295 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 = ...