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

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GRASS: strange classification output and reject map from “i.maxlik”

I am trying to perform a supervised classification with "i.maxlik". I have three bands: 1) elevation (a dem); 2) reflectance (derived from Landsat ETM+ band4); 3) cumulative solar radiation (derived ...
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51 views

Clipping raster objects in PostGIS

I'm trying to cutting a raster object (from a PostGIS table) using a shapefile with reference, extracting raster data from a polygon area. My objective to work with the clipping raster into R. I'm ...
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2answers
144 views

Where is World hillshade free download?

i need world hillshade with resolution about 1x1 km. Do you know where i can it download ?
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47 views

Not all raster layers redraw

I'm running QGIS 2.12 and have the same issue on 2.8, but it is now worse in this latest version. The issue is that not underlying raster layers (satellite photos loaded in as .tif) are being ...
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1answer
43 views

Standardising DEM raster for a MCE

I'm trying to complete a Multi-Criteria Evaluation for an MSc assessment and am in the process of standardising my factor maps. Unfortunately, my DEM layer (ASCII file) keeps changing from this: ...
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1answer
23 views

Inserting legends and co-ordinates in ndvi

I would like to know how to insert legends for the calculated ndvi in qgis. Also how to mark the co-ordinates in the ndvi calculated in qgis.
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1answer
33 views

Error while executing v.rast.stats command in grass plugin in qgis

I have a vector polygon which I imported in grass. I also have a raster from which I have to extract the value. I ran v.rast.stats command in QGIS 2.12. The command was executed with error. The error ...
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1answer
31 views

Extracting raster values to polyline feature

I have a line overlaying a raster containing slope values. I would like to use the line to extract the slope values, and return to its attribute table an attribute containing percentage of slopes ...
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1answer
36 views

Raster Calculator to extract elevation and slope conditions in ArcGIS for Desktop?

I've got a DEM ("ASTER_Nepal.tif") and a slope ("ASTER_Slope.tif") and am trying to create a new raster for elevation values between 2000 & 7000m and between 5 & 60 degree slope. I've tried to ...
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37 views

Standard deviation and average over 1000 images with random null values

I have a large collection of raster files that I would like to calculate the standard deviation over. The first issue is that ArcGIS cannot process over 1000 rasters via cell statistics, so I decided ...
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1answer
23 views

Table Select does not work in Model Builder, when using parameter in SQL

I'm trying to create a model that uses values from a single table, in order to perform a different calculation for each raster in a file. Each raster is represented in the table by a row that contains ...
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2answers
34 views

get first levels of Raster Data

I have a huge raster tif file 40GB, when I use this file in ArcMap it is very slow, I want to use this file only for the first levels, so I don't care about resolution. I don't want a compression I ...
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27 views

Convert Raster to other format No data problem (ArcGIS)

I am converting a raster tif file into other tif file with JPG compression to reduce the size. The original file have a NO-Data value. after conversion some areas have almost black color (1,5,1), ...
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44 views

How can I smooth a discrete raster in ArcGIS?

I started with a continuous spline raster of hotspots, classified by standard deviations from the mean. This displays as 7 classes, but since it's a continuous raster in ArcGIS 10.2, it appears nice ...
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4answers
100 views

Transform raster donuts to circles

Let's assume I have a raster image consisting of 0's and several donut-shaped rings of 1's. This raster could for example be the result of classifying a satellite image with ponds and lakes in it into ...
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1answer
144 views

Georeference raster in non horizontal plane

We have raster data which is generated from (vertical) walls. We would like to keep this data in a postgis database and have the spatial reference encoded "the most accurate way". Currently, they are ...
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88 views

display of raster in QGIS - cells are not rotated

when viewing rotated rasters in QGIS - the overall raster is rotated (as designed), though each grid cell is not. (the nodata value doesn't appear to pick up as the default in QGIS either - ...
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1answer
20 views

Combining two euclidean distance rasters in Raster Calculator

I have two euclidean disance rasters and would like to combine them for use in a multi criteria evaluation. Could anyone advise me on the syntax to use within Raster Calculator (ArcGIS 10.3.1)? There ...
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1answer
28 views

Accessing array of values(height, intensity) associated with raster from ArcObjects without looping?

I am trying to access the array of point values(mainly height and intensity) from a raster through C# without looping through values. I am looking for a direct pointer to the array of values inside of ...
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1answer
25 views

Calculating Categorical Raster Areas per Polygon

I've got forest fragmentation data from which I've extracted pixels that correspond to forest edges and patches. I've also got a shapefile of counties in a US state. I'm trying to get the area of ...
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80 views

Do I need to reproject a NAD83 raster (with no projection) before using it with a shapefile that has a specific NAD83 projection?

I am relatively new to using ArcMap, so I apologize for what I guess is a relatively easy question. I working with a gridded PRISM precipitation raster (www.prism.oregonstate.edu), which has a ...
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1answer
36 views

Use raster as a template/fishnet

I've finally been able to get two rasters with the same pixel size and perfect overlap (resample + snap raster). Now I need them to have the same extent, giving the value of "-9999" in pixels not ...
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20 views

How do Arc Grids and file geodatabase rasters differ?

I know that they are stored differently, but I'm interested in comparisons such as storage capabilities, access speed and data types. I've searched the web but haven't found any such technical ...
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1answer
23 views

Project to NAD83 (epsg:26912) with projectRaster - gives epsg:2152

I am working with some Landsat 8 images from the U.S. Geological Survey (USGS) Earth Resources Observation and Science (EROS) Center. I am processing the images in R, and after masking the clouds, I ...
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58 views

'Extra' Pixel in Nightlight Raster Data

I am new to GIS and working with gridded data so please excuse me if my question is simple or if I miss an obvious point. I want to work with 30 Arc Seconds Nightlight Data (my data comes from NOAA: ...
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30 views

Create kml from binary raster

I have a binary raster (values - 0 & 1) - I want to create a shapefile (KML for use in Google Earth) of the white area only (value = 1). Is there a simple method to do this?
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52 views

Error to add store through cURL REST API too geoserver

I have problem with adding raster layer to geoserver automatically. I need, that geoserver add layer without person job, only script action and i saw that it may be done with cURL REST API but, i ...
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0answers
39 views

QGIS raster calculator - crash minidump

I'm new to QGIS and using version 2.10.1-Pisa. I have two raster layers created from ASTER DEM data. I have one for slope and want to create a binary layer where only pixels between 8 and 60 degrees ...
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2answers
58 views

Creating flt (floating point raster) with QGIS

I would like to create a flt (floating point raster) with QGIS to use later as a terrain in Hec RAS RAS-Mapper. With Raster -> Conversion -> Translate there is no option to create a flt. Is there ...
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1answer
53 views

How to ‘invert’ or ‘reverse’ a vector cutline when gdalwarp'ing a raster?

I have a raster of North America and I'd like to remove the larger lakes from it, replacing them with the same no-data value as the original raster. So I downloaded Natural Earth's 10 meter lakes ...
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22 views

Zonal Statistics on discrete values in raster using ArcGIS for Desktop?

I am using ArcGIS 10.3 for Desktop. I am using Corine Land Cover raster data for Southern European Countries, this data gives discrete values to particular land uses (e.g. 1 = agricultural land, 2= ...
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32 views

Why does the flow direction tool in ArcGIS desktop give wrong output (unique values from 1-255)?

I ran the flow direction in ArcGIS, and received unique values ranging from 1-255. I know that these values are wrong, and should be along the lines of 1, 2, 4, 8, 16, etc multiples. The DEM is ...
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29 views

Aster DEM damaged file (N30 E041)

I tried to merge several raster data sets ( from Aster GDEM), but one file is possibly damaged and I get a hole in my raster, see here ...
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1answer
71 views

How to find a point with highest elevation in area using ArcObjects

Is there a way to find a point with highest elevation in specified area by using ArcObjects? Let's say that I have a raster with DEM and I would like to establish some areas of interest in this ...
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66 views

Error in opening Raster dataset in qgis “Cannot open GDAL Dataset”

Error in opening Raster dataset in qgis (see image below). Is there any suggestion as to why this is happening? and how do i correct it?
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1answer
71 views

stack rasters with different extent and resolution in a loop with R package raster

I would like to stack rasters with the R package "raster". Layers are in ascii format. I want to crop them to have the same extent and project them to have the same resolution. My code gives raster ...
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2answers
84 views

How to determine objects area (size) measurement error using satellite images?

I am working at scientific paper about measuring object's size (it's area) using satellite images. I got some progress in it and need to compare my results with other scientific works. I have found ...
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1answer
49 views

How to attach latitude and longitude values to pixels values in ArcGIS?

I am trying to create space time cubes of LANDSAT 8 images in ArcGIS. The space time cubes can be created using only feature classes, so I need to convert from TIFF to pixel values with Dates and ...
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13 views

IRasterLayerExport3 doesn't save raster until ArcMap closes [closed]

I'm trying to export raster using IRasterLayerExport3, but it saves raster file only after closing ArcMap. It seams that IRasterLayerExport3 creates placeholders for raster (empty file - 3kb), and it ...
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1answer
21 views

Cell Statistics failing to read rasters in list

Heyo. I'm trying to get the rasters from a list (about 32 rasters) and then sum them up with CellStatistics in arcpy. I'm using Python 2.7.8 and ArcGIS 10.3.1 I got it to work the first time around ...
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32 views

Combining Raster and Vector data

I've created a Watershed raster data set (using the Watershed Tool) for a certain area. Within that watershed raster, there are 8 basins that appear I'm trying add the total population to each of ...
3
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1answer
98 views

Speeding up extraction time of proportion of land cover types in buffer from raster using R?

I would like to extract land cover data in a buffer of 10 km around objects of class SpatialLines and calculate proportion of each land cover type. So, I used the function extract (package raster). I ...
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1answer
49 views

Average of raster elevation based on polygon boundaries

I am attempting to extract and calculate the average height of buildings using LiDAR converted to raster elevation data. I've created a DSM to cover the entire area and I am trying to extract just the ...
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0answers
18 views

How to spread a population data from a vector layer in a raster layer? [duplicate]

I got a shapefiles for provinces in a African country. In each province there is the population data. I've got 3 TIFF (raster), one for the agriculture, one for the cities and the last one for ...
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1answer
50 views

Raster processing in ArcPy seems to “simplify”/“round” my resulting values

I'm working off a DEM and doing some raster algebra with it (real simple, add this decimal value, then divide by this value). The DEM in question is super high resolution LiDAR, that's both spatially ...
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1answer
21 views

What projections and input file parameters are supported by r.resamp.rst?

I always get ERROR: Unable To Seek after I run r.resamp.rst r.resamp.rst input=map30 ew_res=10m ns_res=10m elevation=map10 It actually starts to work but after it finish I get the error and no ...
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1answer
75 views

Optimizing Python GDAL ReadAsArray

I am using the GDAL ReadAsArray method to work with raster data using numpy (specifically reclassification). As my rasters are large, I process the arrays in blocks, iterating though each block and ...
3
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3answers
111 views

Point attribute from underlying raster data TIFFTAG

I have a layer of manually set points in qgis that have the following attributes at the moment : id, lat, long Additionally, I have a number of different overlapping raster images (sattelite data) ...
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1answer
37 views

Clipping raster with polygon for band-by-band output using ArcGIS Desktop?

How do you clip a raster image with a polygon shapefile so that the output is multiple clipped rasters, each one a band (i.e., clipped raster band 1, band 2, and so on)? I've tried the clip tool for ...
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1answer
32 views

Assigning spatial info for NetCDF files using ArcGIS for Desktop?

I have quite a few NetCDF files that arrive from a air quality model without any spatial reference. However, I do have the spatial reference information that is required. Within Arc I use "make a ...