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

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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(...
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47 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 ...
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1answer
1k 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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74 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 ...
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2answers
799 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 ...
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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
217 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
2k 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 ...
3
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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
7k 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 ...
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1answer
618 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
53 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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86 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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0answers
112 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
536 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
361 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
306 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
112 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 ...
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1answer
269 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
146 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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157 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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153 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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97 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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335 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
44 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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0answers
21 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 ...
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1answer
574 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
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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 ...
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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 ...
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252 views

Find correct SRID

I'm learning PostGIS raster, and importing GeoTiff with raster2pgsql. This command line tool states: -s <srid> Set the raster's SRID. Defaults to 0. If SRID not provided or is 0, raster'...
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2answers
636 views

Raster clipping without producing no data values

I'm trying to clip a raster in ArcMap using a polygon, and I'm wondering if there's any way to have the resulting raster not include any "no data" values (I apologize for the poor grammar). My process ...
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241 views

Setting raster resolution in meters when working in a Geographic Coordinate System

I work in WGS 84 (Geographic Coordinate System) in ArcGIS 10.1. I need to create a raster specifying its cell size in meters, and output it in WGS84. Is it a good solution (towards a less shape/area ...
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1answer
325 views

How to determine the optimal raster resolution when interpolating a surface from points?

I'm looking for guidance on how to determine the desired output resolution, when interpolating a surface from irregularly-spaced point samples. I have a series of boreholes taken across a city, and ...
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2answers
1k views

How does Environments > Raster analysis > Cell size works in ArcGIS?

How does Environments > Raster analysis > Cell size works, when creating a raster from a polygon using ArcGIS? I have tried to handle both "Maximum of Inputs" and "Minimum of Inputs" and nothing ...
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3answers
55 views

Raster statistics

In ArcMap, I have a raster layer representing site locations. I derived elevations values for the sites from a DEM. Now want stats on distribution of elevation values at those sites. How can I do this?...
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2answers
1k views

Troubles exporting raster to tiff in ArcGIS

I am exporting in ArcGIS a raster by doing Data > Export data. But in the Export Raster Data window, I don't have the option for choosing the file format. Am I missing something? Perhaps must the ...
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2answers
492 views

How to set the cell size of a tiff to 1 meter when working in a Geographic Coordinate System?

I am working in a Geographic coordinate system in ArcGIS, and I need to create TIFFs by exporting rasters. THese .TIF file must have a resolution (cell size, or GSD) of 1 m. Is it possible to set any ...
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votes
2answers
825 views

How can I extract all distinct values from a PostGIS Raster?

I am working with an integer raster in PostGIS 2.1 and I would like to extract all distinct values in that raster. I was hoping to be able to do something along the lines of the following query, but I ...
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1answer
449 views

How to convert raster to im object for point process model covariate in R

I am trying to convert a raster object to an .im object for use with a point process model in the spatstat package in R. I begin by creating the raster from a tiff file using the raster() package. No ...
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221 views

using r.volume model GRASS plugin in QGIS

I am calculating volume of bathymetric data in the form of a clipped raster in GRASS with a Custom Lambert projection centered around 70degrees North, using the module r.volume in GRASS. Side note: ...
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156 views

List of vector to one raster in PostGIS

Hi PostGIS developers! I need to rasterize a part of OSM map by coordinates. I found rather good algorithm, but can’t finish it. I have problems in STEP 3. I described all algorithm here – may be ...
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1answer
163 views

What do pixeltypes in PostGIS raster mean?

I'm trying to build a raster in PostGIS from a vector layer and I was curious as to the meaning of pixeltypes in the raster geometry? How does it effect my raster?
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185 views

Making grayscale map from multiple band satellite image in ArcGIS for Desktop?

I have satellite multiple band map, I needs to make grayscale map,what should i do? what is the steps? which band and format of input are to be used in this? How to make attribute table of this? In ...
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1answer
579 views

How to know the GSD (grid size, resolution) in meters of an existing raster when working in Geographic coordinates?

I would need to know the GSD or grid size (resolution), in meters, of a raster created when working in a Geographic coordinate system in ArcGIS. Is is possible? Even better, can I set the Cell size ...
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1answer
73 views

How to output the number of channels in a .JP2

I am looking for any tool (or python code snippet) that can loop through a file folder of .jp2 images and determine which have 3 bands and which have 4 bands. I am having trouble creating a raster ...