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

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112 views

How can I confirm the existence of pyramids in QGis?

I have created pyramid layers for my ASTER satellite images (.img) using Gdal Tools "Build Overviews" (Pyramids). The dialog said "Processing completed". I don't have the impression that zooming in or ...
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1answer
159 views

Lack of Options in Gdal Tool “Build Overviews” QGis

I am using QGis 1.8 and I want to build overviews (pyramids) for satellite imagery using the Gdal Tool. I would like to use the resampling method "cubic convolution", but the option doesn't exist ...
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1answer
130 views

Geographic Transformation

I have an Image with the following metadata: Projection Information : Projection Zone : 0 Spheroid Name : Modified Everest Georeferenced to : RSO Map Information : Upper Left ...
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1answer
70 views

Raster image outside Grass screen, How to get it inside from start?

HI ALL: I'm new in Grass and need some help! I have created a LOCATION based on the coordinate system in which I want my data to be projected. So far I'm being able to Import & display the raster ...
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2answers
389 views

How to create a raster (topo to raster) with non-rectangular shape?

I'm using Arcmap 10, I need to create a raster from contour lines. These contour lines were clipped out with a certain shape with the purpose to modify them only within that shape and then create the ...
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1answer
101 views

How to make a new raster out of two other rasters [duplicate]

I have two raster images, one is the Corine Land Cover for the year 2000 and another one which is the anthropogenic effect on land. The first image reclassified in 9 categories: Artificial surfaces ...
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0answers
157 views

ArcGIS Spatial Analyst “Sample” returns Null values

Using "sample" to join raster values onto point data, some of my points get assigned a Null raster value. The raster does not contain Null values and definitely looks like it has a value at the ...
2
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1answer
110 views

Display a raster stack with several bands in ArcGIS?

I have already made a raster stack (5 bands in one TIFF) of my multitemporal Landsat images in R and have also clipped a smaller region of every raster stack for each image. Now I want to do some ...
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1answer
119 views

Spliting layers from multispectral images

I have an image with 4 bands and I wanted to De-layer stack to have each bands separately. How and with which software I can do that? Thanks
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3answers
312 views

Vector Machine Classification in ArcGIS

Is it possible to perform a vector machine classification of raster image using the ArcGIS software package. This supervised classification method is available in the ENVI software but not for ArcGIS. ...
0
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1answer
2k views

Help dealing with a GeoTiff-file in ArcGIS

I'm doing data-analysis on satellite data and my source data is in GeoTiff-file format. What I would like to do with the data is: 1) Open the raster data in ArcMap etc. 2) Change the coordinate ...
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0answers
120 views

Why are my raster mean and standard deviation -1?

I have a set of about 25 rasters whose descriptive statistics I have been examining. The data in the rasters were calculated in Python and the rasters were created using Python-GDAL. In all but one ...
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1answer
80 views

Raster Data set Size on Disc (ArcGIS)

I have just converted a vector dataset of census tracts into a raster data set for an assignment. I can see the uncompressed size of the dataset in layer properties dialog box. But the assignment ...
3
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1answer
999 views

Iterating through an numpy array and index to a value in another numpy array

I am struggling to get this code to work I want to iterate through an numpy array and based on the result, index to a value in another numpy array and then save that in a new position based on that ...
6
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1answer
220 views

Raster smoothing

I am an italian student. I'm using ArcMap 10. For my thesis I need to simulate a debris avalanche, but in my elevation raster the avalanche deposit is included so I'd need to take it off to simulate ...
4
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1answer
220 views

Shortest raster path

I am trying to create a path from the blue square to all the green dots. The blue square represents an existing road and the green dots represent centroids of forest stands. The total path distance ...
2
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1answer
117 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 ...
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0answers
46 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 ...
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2answers
357 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, ...
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2answers
314 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
181 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
816 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 ...
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1answer
98 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
83 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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0answers
93 views

Copy Raster Catalog from .mdb to .gdb, but only within a certain extent with arcpy?

I am stumped again, this website has really helped me before so here is another shot. I am trying to copy a raster catalog from a personal geodatabase to a newly created file geodatabase but only ...
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1answer
221 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. ...
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2answers
420 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 ...
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1answer
1k 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), ...
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1answer
216 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 ...
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0answers
232 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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0answers
139 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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1answer
82 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 ...
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401 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
81 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 ...
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0answers
224 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 ...
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0answers
288 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
680 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
354 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 ...
2
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1answer
802 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 ...
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2answers
343 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 ...
1
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1answer
176 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
158 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
votes
1answer
462 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 ...
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1answer
103 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
73 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
296 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
819 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 ...
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2answers
3k 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 ...
3
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1answer
353 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
3k 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 ...