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

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845 views

Opening GeoTIFF (georeferenced in ArcGIS for Desktop) in QGIS?

I tried to open a georeferenced geotiff created in ArcGIS for Desktop in QGIS. I could open them but they are not in the right spots. These raster datasets contains .aux .rrd .tfwx .tif.aux.xml ....
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52 views

Update Raster extent

How do you update raster's extent after you export the raster ? I forgot to enable the Date Frame rather than it's original Dataset?
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2answers
519 views

Visualization of a field in Leaflet

In a Leaflet app I want to overlay raster data (technically speaking, a field) on a web map. The data consists of triples < lat,lon,value >, where value is in range [0,1], for example: 23.33,10.55,...
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2answers
88 views

PostGIS raster write support in R

I want to push/write some generated raster layers to my postgres database directly in R. In theory this could be supported by the rgdal package, but sadly it isn't. In the latest version only copy, ...
2
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2answers
375 views

Arcpy Slope Analysis Script

I'm trying to run slope analysis in ArcGIS. I have written an ArcPy script that converted feature layers to raster files. Now I have a list of rasters (each with a unique name) in the table of ...
3
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2answers
104 views

OpenWind Zone of Visual Impact transparent pixels?

How do you make pixels which are not visible from a point be made transparent and the pixels which are visible opaque so that I can overlay the raster over a map to see clearly where you can and ...
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0answers
157 views

geoserver and openlayers select rectangle pixel values

I'm running a geoserver (2.5.x) with 1 raster file (GeoTIFF) as a layer. From my application I can access a single pixel value when clicked (through WMS), but what I'm really interested in is to get a ...
3
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2answers
533 views

QGIS ASCII Grid output problem

I have this .asc file of maximum temperature of a local place. This file is a result of vector to raster (GeoTIFF) conversion then GeoTIFF to ASCII grid conversion, both using QGIS. Here is a snippet ...
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2answers
536 views

Overlaying Raster image with Google Maps in OpenLayers3

I am trying to overlay Google Maps with a raster image layer in Openlayers3 and am new to this. Can anyone help by providing the steps involved in performing this task?
2
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1answer
312 views

Subset multiband tiff file using Python in ArcGIS for Desktop?

I have a multiband (1140) raster file in tiff format that I want to subset. Each band represents a prediction of monthly rainfall (12 bands for each year) over a 95 year period (12*95=1140). I need to ...
5
votes
1answer
239 views

What are the PostGIS Raster Constraints used for?

My question is quite basic, but I have not found a simple explanation of why raster constraints are useful. I have worked with rasters in PostGIS for a while but only recently I realized that I do ...
2
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1answer
38 views

Looking for smallish raster of global elevation data

I'm trying to find elevation data for the whole globe for a simple mapping application and I'm not having any luck. I really don't want anything fancy, just something like a 4000x2000 raster of ...
4
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1answer
34 views

raster statistics by line shape (vector)

I have a georeferenced area where I created 7 raster maps (classified with suitability values from 1 to 5) as I have 7 factors to check e.g. natural reserves, floods, slopes etc. From there I did a ...
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1answer
541 views

How to load postgis raster layers into R?

It is easy to get Vectorlayers into R from a PostgreSQL+PostGIS solution. library(rgdal) dsn="PG:dbname=plots host=localhost user=test password=test" plots = readOGR(dsn,"Plots") But how to do the ...
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0answers
50 views

How to get transparent nodata values in GeoExplorer?

I have a single-band raster image with NoData values set to 0. Is it possible to get them transparent in GeoExplorer?
2
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1answer
353 views

Loading raster in postgis and link it with an existing table

Relatively new to PostGIS and I am currently exploring the options to make one of my PostgreSQL Tables spatial. Essentially I want to store a raster object in a table that also contains essential ...
3
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1answer
628 views

make a raster from dataset (csv)

I was trying to make a raster from an dataset (https://www.dropbox.com/s/jsm1x06lnzfbqty/data.csv?dl=0) code: inter1= read.table("c:/data.csv", header=TRUE) #convert to spatial points coordinates(...
3
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1answer
48 views

Fast editing in raster calculator — adding lots of images together

I need to add pictures together to make one raster. In one session there are about 150 - 200 images (named randomly - see syntax example) There are about 50 sessions (named randomly) Is there any ...
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14 views

Error Using Open Layers 3 Web mapping Applications [duplicate]

As being new to website development, i have been able to display map on my website, but I want that i should only zoom to some specific places of india on loading of web pages. Can somebody please ...
4
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1answer
2k views

how to delete a row in grid attribute table of a raster?

How can I delete a row in a raster file table? The raster format is GRID I get this error "grid attribute table is blocked from deletion". It seems absurd that I am not able to manipulate my own file....
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77 views

Distortion in projected raster

I am having a frustrating problem with something that I think should be very simple. I have a number of DEMs from the National Elevation Dataset (NED), that come standard in the NAD83 coordinate ...
2
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2answers
844 views

How to remove the no data area (sea) from a raster in arcmap?

I have some difficulties removing the no data part from a Geotif SRTM . I need to remove all sea part. Im new in arcgis and, help is appreciated. Thanks There you go Sir This is the result i ...
3
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1answer
2k views

Georeferencing a raster using GDAL and Python

I want to georeference a raster using python and GDAL. My current approach is to call gdal_translate and gdalwarp using os.system and an ugly list of ground control points. I'd really like a way to do ...
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1answer
226 views

Create Reduced Resolution Dataset (.rrd) file with modern software

I need to create, very specifically, a set of reduced resolution dataset (.rrd) pyramid files for a large set of TIFF imagery. I'm using ArcGIS 10.2, and have access to Global Mapper and QGIS. ArcGIS ...
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128 views

ArcMap - Adding Multiple raster datasets to mosaic dataset (for temporal change)

I have a number of raster datasets containing lake water temperature data. I am looking to make these time enabled as to be able to scroll through them. I have converted them to .TIFF format and have ...
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2answers
3k views

Reprojection of shapefile in R and final extraction of values

I need to extract values from some raster files (stack) using a shape file. to bring both of them in the same CRS, I first transformed the shapefile using the EPSG codes. Opening it in an GIS software ...
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2answers
2k views

Reclassify rasters using GDAL and Python

Using @SS_Rebelious very useful answer, I am trying to reclassify rasters using GDAL and Python. I have a grayscale raster (with values ranging from 0 to 255) and I want to reclassify it to a binary ...
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4answers
8k views

Converting raster file from float to integer type in ArcGIS for Desktop?

I have a float type raster file (an NDVI made from ERDAS IMAGINE) and would like to convert it to an interger type raster file in order to use Focal Statistics function (Majority). Is there any way to ...
2
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1answer
673 views

Extracting data, not colors, from geotiffs in R

I'm an experienced R user new to GIS, but finding my way. I've recently run into an issue that I haven't been able to find any satisfactory documentation on (but could just be searching poorly). I'm ...
2
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1answer
54 views

Understanding concept of ArcGIS for Flex?

I am a complete newbie to GIS. I am trying to download topographic data from a website that displays a map that can be zoomed in and out. The website is setup with: This application is using ...
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93 views

What are my options to handle Raster Clipper ERROR 6: ADRG driver doesn't support 4 bands?

I have a tif file which contains 4 bands (RGB + alpha). The clipper does not work and gave me the message below; ERROR 6: ADRG driver doesn't support 4 bands. Must be 3 (rgb) bands. Any patch file ...
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1answer
37 views

Select value of zero from a raster and assign new value based on the majority of its neighborhood

I have a raster layer has values +1, -1, and zero. Now I want to select those pixels whose value is zero and assign them new values based on the majority of its neighbor 5*5 cells. Is there anyway ...
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113 views

QGIS 2.4 Clip function in Raster layer Style Single band pseudocolour not working?

I've been using QGIS for a while and recently upgraded to 2.4, but now find that displaying raster layers is difficult. In particular, the clip function (tick box bottom left of "Style">"Singleband ...
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2answers
555 views

Export Raster Attribute Table using Open Source software

I've got 120 or so geotiff files that I'd like to build and export the raster attribute table to something a little more friendly (e.g. csv). I'm curious if there is an open source way to do this. ...
3
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1answer
374 views

Zonal Statistics Tool on raster

I am working on a one-band raster with pixel values from 1 to 7, each representing a land-use class. I also have a grid of polygons and what I need is to obtain the percentage of each class in each ...
2
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1answer
314 views

r.recode rules file issue

I have a raster that I want to reclassify and I'm using GRASS r.recode from within QGIS v.2.4.0. The rules file I am using has this content: 0:149:1 150:229:2 230:379:3 380:459:4 460:*:5 The raster ...
3
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1answer
117 views

Least cost path with one-off cost for highest elevation

I'm trying to write a script to calculate the least cost path between two cells on a raster. I'm reasonably familiar with the approaches used by tools such as GRASS GIS's r.cost and ArcGIS's ...
5
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1answer
280 views

How are raster pixels determined whether they are in or out of a zone?

I just needed to confirm something that I think I already know the answer to because help pages are always unclear. I am running ArcGIS 10.2.2 and often use the Zonal Statistics and Tabulate Area ...
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1answer
154 views

Raster image does not show up in Data View

I'm a new GIS Student. I created and imported 3 raster files for last week's lab. In our lab this week, we are creating a vector image using the raster data. When I import the 3 raster files, it ...
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160 views

Using gdal ReadAsArray or Arcpy.RasterToNumPyArray on python 2.6 32bit without it crashing

I am trying to run ReadAsArray on an entire raster and on a single band, python will crash without an error message when trying to do either. Is there a way I can create a 3d array without having to ...
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156 views

Changing grid orientation of a raster

I'm trying to load some XYZ data into a program called OpendTect. However, the orientation of the existing data is different from the grid orientation of the XYZ file. this makes it imposible to load ...
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0answers
98 views

How to Use GetGeomtype Gdal Python

I am just wondering what I am doing wrong when trying to use the GetGeomType. I need to focus on separating layers from a pix file. Two categories are the bitmaps(which are vectors) and then the ...
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0answers
341 views

Why do comparisons in QGIS 2.4.0 Raster Calculator return -3.40282e+38 aka no_data?

I tried to use comparisons as conditional statements in QGIS 2.4.0 raster calculator. My statement is: (a < 230) * 230 + (a >= 230) * a The expected result is raster a with all values lower ...
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1answer
45 views

Is PostGIS-2.x raster in text format (WKT) only?

I was reading PostGIS FAQ and this tutorial. From all that I can tell, it seems that PostGIS raster is a text format, i.e. WKT or well-known-text. I was wondering if PostGIS raster data are text-...
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22 views

How to merge elevation from a raster image onto a shape road network with QGIS? [duplicate]

I have a shape file with Stockholms road network and a raster image with elevation data from the same area. Is there any way to merge the two somehow, either by adding the slope direction as ...
3
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1answer
1k views

How to perform raster Overlay Analysis using QGIS?

I tried to do a raster Weighted Overlay Suitability Analysis to find the best location for home lands using QGIS. Used layers are: School location (point) Crime locations (point) Road (line) Water ...
4
votes
1answer
597 views

Removing some bands or layers from a tiff using gdal

I have been working on a multiband raster image. It is a pix image. I need to just work on the 26 bands that are raster files and not the 4 bitmaps that are are also included in the pix image. I could ...
3
votes
1answer
2k views

Is there an image editor that can edit GeoTIFFs without affecting their embedded georeferencing?

I know there are a couple workarounds for this but I was hoping a direct solution exists. I am looking for an image editor (like Photoshop but hopefully free software) which can be used to edit ...
3
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2answers
1k views

ArcGIS 10.2.2: How to clip vector data from raster data?

I have two files: National land cover data (raster) HUC 8 (vector files of watersheds) Both are national scale but the HUC 8 takes up a larger geographic region than the raster set so I want ...
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1answer
177 views

Reclassification of raster surface using ArcGIS for Desktop?

I have a raster surface with values ranging from 0 -100. I want to create a categorical classification (percentage categories of 5%, e.g. 0-5%, 6-10%...) and reclassify my surface into these ...