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

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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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1answer
24 views

Convert Shapefiles into Raster — C++

I'm coding an algorithm which uses as an input a map from QGIS. The software has been implemented in C++ and my idea is to convert, automatically, a shapefile into a raster one. Is there any function ...
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29 views

How to extend a (river water level) raster, transfering its values to the added area?

Exploring the raster tools in QGIS and related software, I found raster buffer functions to surround existing rasters. The values of the raster buffer are restricted to be distances from the interior ...
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3answers
2k views

NoData values recognised in raster in ArcGIS but not following symbology rules

I have a GeoTIFF raster in ArcGIS, which can be downloaded from the following two links: http://www.rtwilson.com/downloads/MODIS_MOD04_16-06-2006_Subset.tfw ...
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1answer
17 views

Intersection of two vector tables data in postgresql

I have satellite raster data is converted in to pixels using create table gtru_tile_pix as SELECT (ST_PixelAsPolygons(rast)).val, (ST_PixelAsPolygons(rast)).geom FROM ...
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3answers
50 views

Grass GIS: ArcGIS' “Raster to polygon” equivalent

I've got a small clipped extent of a LANDSAT image and I need to have the single pixels as polygons in order to tell the overlap proportions of overlaying polygons. In ArcGIS I used "Raster to ...
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0answers
21 views

Raster memory usage in R

I am working with raster/brick data in R and running into memory issues. I am basically trying to use raster objects to perform some simple agent-based modeling, but the objects keep increasing in ...
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1answer
94 views

How to speed up raster/map algebra in PostGIS?

I am testing map algebra with PostGIS (2.1 with PostgreSQL 9.3) on two images, and found it to be rather slow. For example, dividing two images of 7200 * 3600 pixels took 110 ~ 120s on a desktop with ...
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1answer
25 views

r.report giving only per-class cell count

I'm trying to extract the count of each pixel value in a raster, like in this question: How to extract pixel value counts from a raster in QGIS? However, when I run r.report (from QGis (2.10) ...
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0answers
63 views

How to tell if map service is fully vector or raster?

sorry if this is a duplicate, but I was wondering how to tell if a map service (in web browser) is vector based or raster based? What I think to understood so far is that Google Maps for example is ...
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7answers
18k views

How to get X Y coordinates and cell value of each pixel in a raster using Python?

I’m really new to Python and I would like to know whether there is a quick method to get cell values of a raster pixel by pixel and the coordinates (map X Y coordinate of centre of each pixel) using ...
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5answers
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Adding Raster Layer without lyr file using ArcPy?

i wonder how i can add a raster layer to a remote (not the current) mxd file with arcpy. I need to not use a lyr file for that. For vector Layer i have the following lines working fine : mxdPath = ...
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1answer
58 views

pyQGIS changing Paletted Raster Layers to Grayscale

I've written a plugin which essentially imports a number of colour geoTifs (map tiles) which works correctly but it would be great to display these as Grayscale after loading in. The geoTifs load as ...
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2answers
30 views

How do you insert values into custom fields when adding to a Mosaic Dataset table?

I have a mosaic dataset (file geodatabase) with an additional field added to it (id that is integer) and I'm trying to accomplish in ArcPy what I can do manually--which is: Add a new raster (single ...
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1answer
168 views

QGIS raster clip error: Cutline not of polygon type

I have a raster file and want to clip it, but I'm getting this error: "ERROR: Cutline not of polygon type" what does this error mean and how can I resolve it?
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2answers
957 views

GDAL/proj4 equirectangular projection coordinate system units assumed by OGRSpatialReference and GDALDataset::GetGeoTransform()?

How do I configure my OGRSpatialReference object to specify an equirectangular projection system http://en.wikipedia.org/wiki/Equirectangular_projection where the affine geo-transform matrix (provided ...
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0answers
5 views

Problem with automated data storing during raster::crop (‘legend’ is not a slot in class “RasterStack”)

I am working with a set of raster layers containing CHIRPS monthly rainfall amounts over Africa. For purposes of reproducing the below code, I staged the decompressed tif files on Dropbox. Now, ...
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3answers
7k views

Differences between Raster Dataset, Raster Catalog, and Raster Mosaic

I have about 40 scanned, colorful Geology maps that are GeoTiffs. I want to bring them into an Esri FileGeodatabase to lower their size, combine them as one and display them with a mostly transparent ...
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3answers
3k views

Selecting vector features that overlay raster in ArcPy?

I have two datasets: point feature class and raster (stored in file geodatabase). The spatial extent of the raster is smaller than the point dataset. Is there a way I could select (or create new, ...
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1answer
151 views

Exporting .tif from referenced mosaic dataset does not use functions in raster dataset

Very frustrating little issue in ArcGIS 10.1 -- I have a referenced mosaic dataset of terrain data that has a series of functions inserted (slope and several iterations of a statistics function to ...
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25 views

raster data and polyline shapefile do not line up

I am working on an ArcMap .mxd encompassing the state of new mexico. I have a shapefile of the state boundary with the following coordinate system GCS_North_American_1983 WKID: 4269 Authority: EPSG ...
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22 views

Georeferencing google earth historical images

I have been trying to raster and georeferenced an historical set of images from Google Earth but I am experiencing issues after done the first one properly. I save 4 images from Google Earth of the ...
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2answers
251 views

Unable to stylize as pseudocolor render type on MAC OSX

In a raster layer's Style Properties, I can choose pseudocolor render type, and choose a color ramp and classify the raster. However, when I click the 'Apply' button, or click 'OK', the ...
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1answer
257 views

problem to open a netCDF and create a raster file

I want to open a netCDF file and create a raster with ArcMap 10.2. The file contains the mean monthly temperature for Switzerland. I found it in meteoswiss web site. I tried to open it with the ...
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1answer
152 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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3answers
34 views

Zonal average weighted by distance from point

I am using ArcGIS 10.2. I have a vector layer with points, which represent houses and a raster layer with values of 0 or 1, according to a certain threshold. In a buffer of 5 km around each of these ...
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1answer
26 views

16Bit Tif In Geoserver

-->Is there any way to publish 16 bit raster image in geoserver 2.7.2? Then i tried to publish 16 bit raster image,but i got different color variations in different zoom levels,If any solutions for ...
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1answer
449 views

How to build an attribute table in a 3-band raster?

I have a 3-band (RGB) raster file from CORINE and the attribute table hasn't been built. When I try to execute the command BuildRasterAttributeTable I get an error that only single band rasters are ...
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2answers
615 views

Histogram Matching using Python to improve mosaicking process of multiple overlapping rasters?

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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2answers
149 views

Measuring distance to roads using raster data in ArcMap?

I am using ArcMap 10.1 on a Windows x64 system. I am trying to analyse the driving force of urban land use land cover changes. I have 7 raster files represents distance to roads, distance to river, ...
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1answer
23 views

Specifying number of columns and rows in a raster file

ArcGIS 10.2 I want to produce a raster file with a specific number of rows and columns - 300x300. This needs to be reproducible on multiple data sets/locations - so fixing the extent of the file ...
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17 views

Raster Area within a Polygon

using ArcGIS, I have a layer of overlapping polygons and a raster grid underneath. The raster is not a continuous grid - the cells are spread out. I simply need to calculate the total area of the ...
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1answer
164 views

Cannot get 2 raster files of same cell size to align ArcMap 10.2

I have two raster files that are the same cell size but I cannot get them to align properly. (I want the black to line up with the pink) When creating the black raster file (from using polyline to ...
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2answers
85 views

LiDAR intensity image from multiple flight lines?

I'm working with multiple raw las tiles, and I've used Fusion to create an intensity image, but it shows the flight line overlap (see below). Any idea how can I smooth the image so that the overlap is ...
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2answers
905 views

How to label raster cells using ArcGIS Desktop or QGIS?

I want to generate a small sample raster (eg. euclidean distance or cost distance) to explain the method of cost-distance analysis, and I'd like to label the pixels with the corresponding cost-value. ...
3
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1answer
68 views

Clip raster by raster with data extraction and resolution change

I need to stack multiple maps (tif) together and clip them all according to extent of one small raster map (second raster at the top of picture below). However, the size of pixels in each map is ...
0
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1answer
203 views

Issues calculating range with QGIS 2.0 raster calculator

I would like to calculate a simple range using the QGIS 2.0 Raster Calculator, but am getting strange results. I believe I am not using the correct syntax. To get all values between .003-.5, I ...
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1answer
86 views

Raster cells with no data being generated by las2dem?

Anyone has an idea where these lines (with no elevation data) come from? They are generated while using the las2dem tool from LAStools. What needs to be done to avoid this? The raw data (.las file) ...
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1answer
618 views

How can I get my georeferenced TIF file to rectify?

I have added a TIF file (size 1,433 KB) in ArcGIS 10.2.2 and defined numerous georeferencing points, with the aim of creating a raster file for conversion to polygons. However, on clicking the ...
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1answer
41 views

GRASS 7 Cost surface and elevation points development

I'm a new to GIS and I need some help. At the moment, I'm trying to develop an optimal path across an area by using GRASS 7 features. It is very similar to the task given here. The problem is that I ...
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1answer
24 views

Display 8-Bit Signed Rasters with Negative Values in QGIS / MapServer

When loading 8-bit signed rasters with values from -128 to 127 into QGIS or MapServer, negative numbers are not recognized. Is there a way to change the default display settings in QGIS and/or ...
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2answers
322 views

Rasters added to mosaic dataset only display at large acale

I have a set of 357 rasters in .jp2 that I've added to a mosaic dataset. All but 7 of them display properly, but the 7 only display at larger scales, around 1:6500 and under. I've tried adding them ...
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2answers
66 views

Mosaicking several TIFF files

I have around 20-30 tiff files all georeferenced and I am trying to mosaic the data however I can't seem to remove the border of these historical scanned images. I have tried shrinking the footprint ...
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0answers
15 views

Raster math with iterator (arcpy)

I know what I am trying to do here is wrong. But I was hoping for something similar that would do the job. Basically, I need a placeholder for values and raster calculations until I sum them ...
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0answers
18 views

How can I work out the percentage of different raster parcels in a polygon

I have a raster layer (LCM2007) that contains 24 classes of landcover and a shapefile, polygon, which represents areas in a survey. I want the area, or percentage, of each class in each area. For ...
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1answer
22 views

QGIS: How to change symbology of a continuous raster to discrete with unequal intervals?

so I'm new in QGIS and currently trying to convert my ArcGIS-layers into QGIS. One of these layers is a slope gradient raster. I want to change the symbology so that a specific rang of gradients ...
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2answers
37 views

Update raster pixels on a DEM

I have a DEM in the form of a raster that I would like to update in certain locations. Ideally, I'd like to be able to create a separate polygon or point shapefile with the values, in the correct ...
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2answers
55 views

Really slow extraction from raster even after using crop?

I have a large raster file (245295396) cells and stacks of rasters having 4 layers each which lie in the extent of this large raster. To start with I am trying to get value from one stack (3 channels) ...
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1answer
42 views

Regarding the Python package PyGeoprocessing, does that need to be installed?

I have not found much documentation on PyGeoprocessing, but from what I have read, I would like to try it out. I downloaded the package from here . . . https://pypi.python.org/pypi/pygeoprocessing. ...
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3answers
210 views

Unable to read raster into R: 'TIFFReadDirectory:Failed to read directory at offset'

I'm getting a weird error when trying to read a raster into R. >r <- raster('myraster.tif') Error in .local(.Object, ...) : TIFFReadDirectory:Failed to read directory at offset 2606110 ...