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

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How to create for each point feature an Euclidian Distance raster in ArcGIS

I need some comment on how to create an Euclidian distance raster for a point dataset of about 100 features in ArcGIS. I need to create a raster for each single point. My question is, if there is a ...
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13 views

“Problem loading output layers” error when running algorithms on rasters in QGIS

I am trying to delineate a catchment from SRTM 1arc second data in QGIS. For this, I first try to use the Fill Sinks algorithm and then the Catchment Area algorithm. Both of the operations gives a ...
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1answer
55 views

How does Resampling raster work at corner cells?

This may seem quite a simple question for which I couldn't find a satisfactory answer. I have been trying to understand how resampling of raster work with ArcGIS 10.3, in both cases of refining and ...
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1answer
39 views

Performing raster calculations with more than two bands in PostGIS?

We need to perform raster calculations using more than two bands in PostGIS. At the moment, ST_MapAlgebra has a two-band form but doesn't support more than that. I'm open to any solution others ...
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1answer
35 views

compare three rasters and three conditions with overlay in r

I'm trying to run an overlay function with rasters where I want to meet all of 3 different conditions at each cell and produce a single raster as output. Running ifelse with the & operator ...
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28 views

Same CRS but different units of raster cells in qgis

I have two rasters with the same CRS (WGS 84/UTM 34N). One is from a LiDAR scan and the other raster is created thru interpolation of point measurements by me. I would like to change the cell size to ...
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1answer
24 views

output raster size in zonal statistics [closed]

Using zonal statistics, my input raster is 1*1 and input value raster is 10*10. I was hoping the output raster will be 1*1 but it is 10*10. What is the error here ?
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46 views

How to use a raster dataset to store and retrieve “vectors” using Python?

For a rectangular area of about 10 by 10 km, I have to generate "displacement vectors" with a 1 meter resolution (i.e. a delta-x and delta-y value for every cell of 1 by 1 meter). I will end up with ...
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48 views

Least Cost Path Distance to nearest polygon

I have multiple polygons (destinations) and an elevation raster. For each raster cell in my study area, I need to calculate the distance to the nearest destination polygon. If I use the 'as crow ...
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1answer
46 views

Calculating proportion of polygon by value in QGIS?

Using QGIS, I have a single-band raster with with multiple counties. I have reclassified the pixels into 2 categories, using a singleband pseudocolor, based on their value ( > or < 3800), ...
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25 views

Stretch to MinMax results in blank render output in QGIS?

I am a new QGIS user, and I can't figure out if I encountered a bug. If I have a multi-layer image, and "Multiband color" -> "Stretch to MinMax" selected I get the following behaviour. QGIS takes a ...
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1answer
33 views

Processing time/speed for Mosaic to New Raster

I have a question on speeding up “Mosaic to New Raster” or finding an alternative. After completing a suitability analysis we are trying to define movement corridors. We used a modified CircuitScape ...
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32 views

Raster area calculation

I would like to know how to calculate area of raster image based on cell? based on night light data I classified the image and i need to know the area of that particular classified area
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1answer
67 views

Why do multiple raster processing tools fail with this DEM?

I have a provincial sized DEM. I need to clip it to a fairly large watershed boundary. Should be easy. I've tried: Data Management Tools -> Raster -> Raster Processing -> Clip (Did I make sure ...
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2answers
24 views

Polygon to raster. How to keep same values?

I have a polygon with values 3, 6, 9, 12, 15, 18, 21, 24, 27 an 30. These are the time it takes for the firetruck to reach certain destinations. Now i want to compare these to another raster that have ...
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19 views

Using numpy.dstack() for merging two 3D arrays but losing spatial reference.

The code is as following: >>> temp = numpy.dstack((spi_negative,spi_positive)) >>> >>> temp.shape (16, 126, 294) >>> out_ras = ...
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3answers
43 views

Delivering DEM layers with visualisation?

I'm not sure if it's right place to do that but I am in a strong need of getting some help. I am creating maps with lake bathymetry and there will be a lot of them. My task is to proceed the data ...
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15 views

Kriging results in log mode and SpatialPointsDataFrame manipulation

I've a little problem, probably because I'm not fully expert with R data manipulation. I've perfomed a kriging elaboration of mydata, in log mode, as the classical meuse example, but how can I export ...
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23 views

QGIS tiff image loaded but not visible

In QGIS I used the Georeferencer on a jpg image I had prepared in Gimp. But when I load the resulting tiff image into my QGIS project it is invisible, even though an image viewing program can show it ...
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33 views

Extracting data of two overlapping rasters

I am trying extract the data of two overlapping set of rasters (one, a stack of 35 rasters, all from the same source and the second an elevation raster) to get a data.frame of the values (mean of the ...
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1answer
21 views

Surfaces and Rasters in DWG format

I have been asked to export a DEM into DWG format, is this possible? The only thing I can think of is to create a regular grid of points and to export this. Also I have been asked to save geotiff ...
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1answer
22 views

Example of C++ code in Visual Studio initializing a created raster

I refer to Sample for MS Visual Studio C++ using GDAL library I noticed that the answer mentions that when GDAL is built from source there would be a tools folder with examples of how to initialize a ...
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1answer
45 views

Calculate data from a set of raster files

I need to make some calculations with data from raster files saved in my postgis database. I need, build a map, using the average from a set of these raster files, for example. Besides, I need to ...
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27 views

Using arcpy.CopyRaster_management function convert raster to 64-bit raster?

I am writing a Python script tool that takes a raster as an input parameter. I want to use this input to create a constant raster that is saved to an output geodatabase (which is another parameter). ...
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2answers
57 views

How do I cut a donut hole in a raster in QGIS

I have a DEM(1) of a bigger area and a higher resolution DEM(2) in a small part of the same area. I would like to cut a hole in DEM1 and replace it with DEM2. Is there a non python way of cutting a ...
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14 views

Check if raster (part of) lies within a pixel - python/gdal

I have a list of the corner-coordinates of different grid (c1-c4). First i sorted these coordinates to ensure that c1 is the upper left, c2 is the upper right, c3 is the lower left and c4 is the lower ...
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1answer
17 views

Conditional Combine Rasters and Track which Raster pixel used

I have 6 rasters with pixel values ranging from 0 to 1. I want to extract the highest pixel values from each raster to create a new raster, but also have a way to show which raster the highest value ...
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22 views

Add raster layer or a WMS using geotools - problem to run the jar file from cmd

I am using geotools in order to develop a custom GIS. So, i tried to add a raster layer and a WMS based on the tutorials given by geotools. When i am running the project using the main class in ...
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11 views

What are the standard ways of querying raster layers for information?

My use case involves loading raster maps as a layer on a base map (built in Mapbox/Leaflet) such as: http://landcover.usgs.gov/global_climatology.php or http://due.esrin.esa.int/page_globcover.php ...
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4answers
163 views

List of GDAL raster file extensions

I am trying to compile a list of file extensions that are accepted by GDAL, something like ['.tif', '.png', '.jpg', '.jpeg', ...] I found a list of GDAL Raster file formats, but the values in the ...
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1answer
42 views

Is it possible to locate a specific marker point on a raster using python and use that location for georeferencing

I have several scans of the same map, which I would like to georeference. I can not use arcpy.WarpFromFile_management(...) as the rasters are slightly different due to scanning. Is there a ...
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1answer
45 views

Counting number of pixels/cells with particular value in raster using ArcPy?

I have a raster image containing values ranging from 1 to 10 in Integer format. I want to count the number of pixel with value = 1. Is there any method in Arcpy which returns the pixel count if ...
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25 views

geoserver load image mosaics tiff files

I have a massive amount of tiff files (+prj. all together 100k). For test purpose I have loaded a small bit of these into geoserver and worked fine. But when I try to add to the store the data folder ...
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1answer
48 views

How can I modify the coordinates of a raster in the QGIS?

How can I modify the coordinates of a raster in the QGIS? i.e. longitude and latitude (geographical positions) I need to modify X Min = 144964.482217 X Max = 150226.504610 Y Min = 4398796.699505 Y ...
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1answer
48 views

Polarity of Slope raster for use in Multi Criteria Evalution

I'm looking to use a slope raster in a MCE however i am struggling to ensure it has the correct polarity. The polarity of my other two layers is high values = good and low values = bad. The slope ...
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1answer
51 views

Round() does not return an integer raster in R

I want to convert the datatype of a raster to integer. For example: x <- raster(nrow=10,ncol=10) its datatype is float dataType(x) [1] "FLT4S" then I round the pixel values of x by y <- ...
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1answer
54 views

how to save a raster after converted from numpy array?

I'm trying to save a raster after calculation in numpy array. Here is what I wrote: rasterSM = arcpy.NumPyArrayToRaster(SM, lowerLeft, cellSize, value_to_nodata=nodata) rasterSM2 = ...
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2answers
38 views

How to calculate the intersection within the grid and saving to the grid

Here is my example: (1) I creat the grid line layer using MMQGIS plugin (2) I use line intersection function to get the intersection points. I want to calculate the distance sum within each ...
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1answer
62 views

Crop raster from vector problem

So I have a shapefile of a vector for Philadelphia's city lines and a raster image of Philadelphia county that I got from the lovely people from USDA:NRCS. I converted the raster from a sid file to ...
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20 views

How to iterate a raster calculator with a change in the input raster and in the values calculated? Than, how to put the results in a table?

What I do without iteration is the following: Change radiance to reflectance for band 3 with raster calculator Samething as #1 on band 4 (the values in the formula are different from #1) Calculate ...
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2answers
71 views

Vector to raster conversion [solved]

I'm using GRASS but, in case, I'm also familiar with R and QGIS. I'm trying to convert a vector area map into a raster one. My problem is that the resolution of the raster is too low (and I can't ...
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0answers
52 views

Using Python to convert line shapefile to raster, value=total length of lines within cell

I have already read the similar question Convert line shapefile to raster, value=total length of lines within cell using R. And I want to realize the function using Python. ===== My attempt ==== ...
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40 views

Turning simple raster file into DEM?

I'm using QGIS LYON 2.12.1, and I want to turn a plain gray scale raster file (that I got from Google search) into a DEM. The aim is to apply the DEM (terrain models) function to the newly created ...
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1answer
18 views

How to create multiple external overviews for a geotiff with gdal?

I want to have mutiple overview files (one for each overview level) for a GeoTiff, so I'm able to edit this files in a raster editor. How can this be done? Unfortunately, gdaladdo -ro creates only ...
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1answer
13 views

Create image using raster photo layer with vector shapefile overlaid (landuse)

I am a beginner with QGIS. I have a raster aerial photo and wish to overlay a vector shapefile (I have already created) showing polygons of land use. Can this be done in QGIS, or do I need to use ...
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2answers
66 views

How can I calculate flow length in QGiS/GRASS?

I have these rasters: DEM Flow Direction Flow Accumulation I would like to calculate the flow distance of every pixel to the outlet of a basin. In Arc-GIS, I can use the flow length. But I don't ...
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1answer
47 views

How to find the cell location index of a raster using Lat long information?

I have a raster for which I want to find the Cell Location (Row, Col) if I have the Lat-long information. I know how to get the value of a particular cell using lat long. ...
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1answer
40 views

creating unique sets randomly distributed values for many defined areas…in a raster.

I have a large approximately circular study area comprised of 5000+ polygons which represent forest parcels. For each of these polygons I have up to 4 different species. These species occur in ...
4
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1answer
62 views

Buffer from Point or Polygon with Information from Raster

The intent of this work is to define a buffer around a point or polygon based on information from a raster. For instance if a polygon representing a city and the raster defines how long it takes to ...
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21 views

How to create a numerical mask file with the elevation points of an area with QGIS

I'm using QGIS and I have to create a mask file (.txt) as an input for a hydrological model. The file should be a numerical grid map that represents the elevation points of a catchment area, like the ...