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

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Working with Interrupted Goode Homolosine data

I'm trying to use Global Land Cover Characterization data from the USGS: http://edc2.usgs.gov/glcc/fao/data_specifications.php It is in the Interrupted Goode Homolosine projection. As I am working ...
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393 views

Qgis crash when I attempt to open ECW raster format.

I added Ubuntugis unstable repo and installed Qgis, libgdal-ecw-src, libecwj2-3.3 but still do not work. When I attempt to open an ecw file with Qgis it crash and tells me that there are problems ...
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79 views

Adding raster image to Raster field with Python?

I have a feature class with with field that is of Raster data type. I want to add an image to each record in the feature class. Is it possible to use Python to add the image to the Raster field for ...
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461 views

How to Smooth Polygons after converting DEM using Raster to Polygon?

I have a DEM SRTM that I classify using Spatial Analyst Tools > Reclass > Reclassify. The result is box shaped so I go to Layer Properties > Display and choose cubic convolution. The result is ...
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231 views

How to import binary arcgis maps into R

I have imported arcgis rasters into R. The rasters are binary maps and the legend in arcgis shows this to be binary as the colors are only 0 and 1. Now, when I import the raster into R it is no ...
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392 views

How do I convert from points to raster making the point the lower left corner of the cell?

How do I convert from points to raster making the point the lower left corner of the cell? I'm using ArcGIS 10.1. The default for the "Convert Point to Raster" tool is to make the point the centroid ...
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321 views

ESRI Raster Remap with Decimals

I have a requirement where the user would like to see the output value in a raster as a decimal. The user will input a series of ranges with a cost associated to them. For instance 0-5, 1.20 ...
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54 views

Align OpenLayer raster with OS Mapping Vector

I have an OS Vector map of a town in Ireland. When I load the Google Satellite Raster from the Open Layers plugin, the results are slightly off, by about 2m, probably due to ariel persepective. I'm ...
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61 views

How to deal with the situation when two rasters stacked together in arcgis?

I am doing a project about petroleum geology. There are several formations needed to add attributes (e.g. name, thickness and age). I have the raster data of thickness, so I created a raster catalog ...
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1k views

combine raster and polygon values in R

My question is similar to this one Get Raster Values from a Polygon Overlay in Opensource GIS Solutions but I think I need another step. I have a polygon layer of ecoregions which I brought into R ...
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2answers
484 views

Set Blend Width on Mosaic Dataset, ArcGIS 10

I've made a mosaic dataset of some thermal imagery. There are three overlapping images, seen here: As you can see, there is a discontinuity (jagged edge) between the two images on the right, and a ...
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1k views

Replace NA's with 0 for raster data using R

I am new in R. How can I replace NA's with 0 for my raster data which have spatial information?
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579 views

Histogram Matching Python

I am trying to do histogram matching using Python to improve the mosaicking process of multiple overlapping rasters. I am basing my code on that found at: ...
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138 views

show dwg,as background not as vector

I have some dwg files that i need to show as background on my map, but the DWG is not need to be vector layers, i need only to show them with out the need of using. if i am trying to convert it to ...
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147 views

Can extracting raster values work in polygons' CRS without raster resampling?

I am trying to extract raster values using polygon layer with different CRS. Raster is in WGS84 (EPSG:4326) and the polygons in UTM (EPSG:23031). 1. If I want to work in the projection of the ...
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472 views

Define transparent color in singleband pseudocolor raster layer style

Can I somehow define "transparent" color for values higher than 32000 in raster layer? See the style dialog:
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137 views

GeoTIFF without projection?

I have encountered a GeoTIFF raster files with EPSG:4326 (WGS84), i.e. no projection defined! Is this normal? I would expect raster to be in Projected Coordinate System. Raster is a grid of pixels so ...
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2answers
265 views

Exporting raster data from QGIS in chosen projection

EDIT: it is seeming like some of the time my last method will lead to a correct projection, some of the time it will not. Unsure what's happening there but at least trial and error will get me ...
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2answers
789 views

Clip_management to raster extent outputs larger raster than raster extent

Using Python and ArcMap 10.0 SP5, I'm trying to reproject and clip a large input raster to exactly the same grid as a smaller target raster (same extent, pixel sizes and projection). The problem is ...
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321 views

Sensitivity analysis for coarse scale GIS epidemiological model?

I am working on an epidemiological model with disease incidence rate as dependent variable and environmental factors as independent variable. Disease data is available at county scale whereas ...
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109 views

Copy Raster Tool and 1bit to 8bit

I have a bunch of 1 bit rasters (700+) of scanned maps that I need to convert to 8-bit rasters. It's the only way Geosoft will recognize the spatial coordinates of the TIF as they don't deal in 1bit ...
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871 views

Geoserver with ECW image file

I am trying to show ECW ortophoto as base layer in openlayers. So i found this thread on GIS SE: Geoserver 2.1.1 with ECW (v3.3) support 1. Download Geoserver 2.1.1 from ...
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3answers
294 views

How to use the GeoServer REST api to get a PNG representation of a layer?

Does anybody know if I can retrieve by REST service in GeoServer an raster representation of layer? Just like in for ex. ArcGIS REST Api: When I send: ...
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20 views

Scale factor (constant not linear stretch) GDAL [duplicate]

I need to re-scale a geotiff with gdal. I'm aware that gdal_translate has a -scale function, but i need to actually apply a constant (eg value(x,y) * 100) instead of scale the pixels to within a ...
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1k views

Create a jgw file for jpg image.

I converted ecw file into jpg file with IrfanView, to display the jpg as base layer in openlayers. I understood that I need to create a jgw file to display the jpg file. I found this example: ...
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123 views

How to make raster cells with a certain value stand out in QGIS?

I would like to make my raster cells glow in QGIS. If I have a dataset where only a few pixels has a value, they can be pretty difficult to spot (unless I know where to look). Stretching helps a bit, ...
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199 views

Right raster zonal statistics for NDVI at county scale?

I am currently doing a modeling project at county scale in which I have disease rate as dependent variable and environment variables (such as temperature, NDVI and evapo-transpiration) as the ...
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2answers
150 views

Batch Fuzzifying with ModelBuilder

I am trying to run the Fuzzy Membership on simultaneous rasters in ModelBuilder and I am running into the problem (or bug) where it allows me to change the "Membership Type" but ends up defaulting to ...
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2answers
347 views

SPOT NDVI time series

I have 423 spot.vgt ndvi from first April 1998 till 31 Dec 2009. I want to know how to stack these NDVI to have one image for time series analysis? Or better to ask how is it possible to analyze a ...
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2answers
2k views

How can I use GDAL to batch define a projection?

I have a fodler with 1500 ECW rasters, no spatial reference information defined. Can I use GDAL to batch define a projection for all 1500 in the folder?
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1answer
435 views

Having issues removing white background from Raster images

I've got an issue with 4 raster layers that I have converted from kml files into layer files. It would only allow me to convert them if I used ground overlay and now the 4 raster images are ...
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81 views

QGIS: “No data” raster value for missing rows conflicts with data?

I’m having a problem with specifying “no data” in a raster dataset in QGIS 1.8.0-Lisboa. QGIS does fine in interpreting pixels I don’t have rows for as “no data” if I set Layer Properties -> ...
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120 views

How can I see average of raster value over certain area, marked by mouse?

I have a raster in Quantum GIS and I am just exploring it. How can I see average of raster value over certain area, marked by mouse? In other words: How can I select particular area in QGIS? How can ...
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72 views

Speeding up raster to point set function

I have written the following function that takes a raster (always non-skewed) and returns a set of points. As I'm executing it millions of times in my queries, I'd like for it to be super-optimized ...
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3answers
972 views

Loading raster data to postgis

I'm a newbie in GIS technology and need some help in loading a rainfall radar raster data into PostGIS. The raster image is shown here: What I need is to store in the database the radar ...
2
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1answer
1k views

How to overlay two raster layers

How to match two raster layers, I have one raster and a shapefile and I want to convert the shapefile into raster BUT I want it to have the same cellsize and its cells overlay (same positions) to the ...
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1answer
2k views

ArcGIS - make linear regression across multiple raster layers

I have a series of 5 rasters which represent a value for 5 consecutive years. Is there a way to create a linear regression for each cell over the 5 layers and output the slope? The result would be a ...
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2answers
763 views

Select maximum values from list of raster layer : ArcMap10

I have 10 raster layers. Each layer has the dimension of 100 columns x 100 rows and actually are temperature values from year 2000 to 2010. I want to ask ArcMap to produce a raster layer that ...
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1answer
193 views

Aggregating a raster to fit a polygon grid

I am working at the scale of 10 square km grid cells for the UK, and have a polygon layer of the Ordnance Survey 10k grid cells in ArcGIS. I have another layer of the human footprint index, also for ...
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247 views

Resolution difficulties in Grass

I have gone through similar questions to mine here, but I didn't find a solution. Please help! When cropping a raster image by using g.region & r.mapcalc, I get a new image but the resulting ...
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2answers
528 views

Parallel Computing and Raster Operations in ArcObjects gives cryptic error

This is a problem I have been struggling with for awhile. The code below takes 1-3 input feature layers (pFLayer) that were stored into a list called pFeatureLayerCollection, casts them into ...
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2answers
270 views

Read raster value at mouse position

I have raster layer imported in QGIS. How can I read value of the variable represented by the raster at mouse position? I just have a new raster layer and I want to read values at random places to ...
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94 views

Why does a shapfile shift after transformation?

I have a shapefile created in the raster package (ER_14.3_2000_poly). > #read in a raster file > ER_14.3_2000<-raster('E:/Ecoregions Models/Outputs/ER_14.3/ER_14.3_ConsensusMap3.asc') > ...
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46 views

How to reclassify raster data on a scale of 0-1? [duplicate]

I have various raster layers generated after using euclidean distance tool. How can I reclassify them on a scale of 0-1 instead of 1-10, etc?
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1answer
692 views

How to run an AML in Python?

I am trying to run an AML in a python program I am writing and haven't been having much luck figuring out the correct way to run the AML. The AML requires ArcInfo Workstation to be from the GRID ...
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1answer
149 views

Installing raster resampling module in QGIS 1.8

On the website of Sourcepole, I have recently come across the case of resampling images in Quantum GIS. Because I am rather a beginner in GIS software I would like to ask you for information about how ...
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191 views

Several algorithms done for topographic correction => black spots - how to solve?

I have done several algorithms for topographic correction in R including simple cosine, Minnaert, SCS. The input data aspect and slope for the hillshade raster have correctly been done in radians. The ...
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1answer
231 views

How to get mean of pixel values within a buffer zone around current mouse position in QGIS

for a qgis 1.8 python plugin I want to query the mean of all pixel values of a raster layer within a defined buffer around the current mouse position, not for an existing point layer. For the buffer ...
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1answer
195 views

How to draw a custom map on top of base layer

I'm looking for the easiest way to draw a custom layer and export it as a tile cache. Basically what I would like to be able to do is load a base layer, and then draw objects and annotations on top ...
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153 views

How to create a single contour defining the boundary between sea and land

Hello! I am still learning so forgive me if my question is very simple... I am trying to create a map with ArcGIS. The area I am working on is a seasite and I found that in some parts the cells appear ...