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

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Rasterize points in a map : result is not leasible. How to make the raster (points) bigger?

I have a vector layer (points) that I rasterized based on one attribute of the vector layer. I chose the GRASS GIS 7 command : v.to.rast.attribute. The raster layer appears in the map, but is not very ...
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33 views

Displaying raster images using Leaflet?

The purpose is to create a small web application using an open source product, preffered Leaflet (but I will Switch the product if it works within another Framework than leaflet), simply showing a ...
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33 views

Configuring Project CRS to reflect degree coordinates

seems like this is a common problem, but posts with similiar questions did not solve my problem. I have close to zero GIS background so apologies for my ignorance. My goal is to extract only a ...
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1answer
23 views

Using ModelBuilder to create smaller individual DEMs from a large DEM using multiple polygon?

How can I use a polygon (which is made up of smaller polygons) to create individual DEMs from a large DEM using the polygons as the mask/extent? I am trying to do this in ModelBuilder and it isn't ...
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2answers
26 views

Add raised features to digital terrain model in QGIS

I have a DTM onto which I need to 'stamp' a series of raised embankments. The DTM is a raster grid (in m above sea level) and the embankments are polylines containing the crest height (also in m.a....
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31 views

Error executing algorithm Clip raster by mask layer 'NoneType' object has no attribute 'GetGeoTransform'

Processing modeler: GDAL "clip raster by mask layer" tool I have a raster layer that I wish to be clipped by a polygon layer (buffer zone). I intend to repeat to process many times in a more ...
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29 views

Iterating columns and feature to raster conversion?

I cannot do iterations on fields correctly. The fields contain rain intensities. Each field represents a time ... 15 minutes, 30 min, 45 min .... I have 50 fields. I want to end with 50 raster ...
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210 views

Automatic selection of pixels, from a raster series, greater than minimum image of the series

Given a series of rasters, and the raster image of the minimum values of the series, I am looking for a python script capable of selecting, for each raster, the pixels whose values are greater than ...
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70 views

How can I select points within a part of a raster?

I have a map with huge amount of points (9562 villages) and two rasters: population density and land elevation. I am trying, without success for the moment, to select just those villages with high ...
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41 views

Determining height of raster class from DEM?

I have a raster layer with 2 already determined classes: Low vegetation and High vegetation. They don't mix, there is a characteristic border between them. It's a typical situation of altitudinal ...
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40 views

NumPy to GeoTiff for use with Gdal

I have a few NumPy arrays: lat, lon, and 6 data bands. I'd like to convert these to GeoTiff and then apply the gdalwarp function, based on a specific projection, to each band. Is there a standard way ...
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28 views

How to remove the Na values from a stack of rasters?

In R I have a stack (nsw.stack) which contains 6 variables. I have clipped the extent. However, When I look at the summary it appears that there is a lot of NA values (see below). I think this is ...
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25 views

QGIS Lost precision when converting raster to vector

I am after running ordinary kriging, converting raster to vector I lose decimal value and only get whole number. I have added first the raster then the vector image.
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2answers
33 views

How to convert a raster output in a stack in R into ArcGIS

I am modelling the response of a bird (skylark) to various climatic and topographical variables in the program R. Using the predict function I predicted the abundance per pixel (see below for code). I ...
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1answer
23 views

Updating a raster using a shapefile [closed]

I have a huge raster file and want to increment all the values within a relatively small shapefile by 1 in Python. Speed is of critical importance, as I have to do this many times. I have been ...
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1answer
29 views

Iterating over a raster layer in ArcGIS using Python

I have a raster layer for drive times. I have another raster layer with my bounding geography. I want to tell ArcGIS: For every cell in geography: if the corresponding cell in drive time is not ...
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1answer
40 views

Is there a standard color palettes for the spectral indices?

Is there a standard color palette (or most commonly used in publications and other materials) for the spectral indices?
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40 views

Multiple HDF5 files in single GDAL virtual raster

Does anyone know how to generate a single GDAL virtual raster linking multiple HDF5 files to each other? Each file represents different swaths of the globe with different lat/lon coordinates and data ...
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51 views

List of Files rename using R? [closed]

I'm trying to rename list of raster files using R, I used the following script which worked just fine: "D:\\Modis_EVI\\Original\\EVI_Smoothed\\" setwd("D:\\Modis_EVI\\Original\\EVI_Smoothed\\") ...
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70 views

mask raster with shapefile using gdalwarp/gdal

I am struggling to use gdalwarp with cutline option. The following command keeps failing and I do not understand why : gdalwarp -cutline shapefile.shp file.tiff newfile.tiff Warning 1: Self-...
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22 views

Arc Viewshed2 requires a vertical coordinate system

When I use the Viewshed2 tool with Arc 10.4, a 010451 error results when I try to add the input raster layer to the tool. The error states that the input raster is missing a vertical coordinate ...
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1answer
34 views

How to reassign Raster values to new values in QGIS?

For example, if the Raster has integer values ranging from -1 to 3 and the value that I am only interested in is 3, I then want to assign values -1 to 2 to 0 and then have the 3 value set to the value ...
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57 views

Raster Catalog QGIS; performance

Is there a comfortable way to generate efficient raster catalogs (such as in Arcgis), where polygon tiles are loaded as long as the scale does not hit a threshold value and images are only loaded when ...
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84 views

Raster calculator creates strange output

I am trying to combine two raster layers (one is nighttime satellite data, the other is the GPW population density data). I am using raster calculator to combine the two (the following is for a ...
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1answer
39 views

Statistical properties of raster image

I want to calculate mean and standard deviation of a raster image. In QGIS zonal statistics, we can calculate it within a polygon or a vector. But I want to calculate for whole image. In Python I'm ...
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23 views

R: Overlay using functions containing if/else statements

I have two rasters, x and y, and I'd like to do calculations with them using the overlay function. For example, MyFun <- function(x, y) x * y res <- overlay(x, y, fun = MyFun) This seems to ...
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32 views

Get indices from pixels with a certain value in PyQGIS

I'm working in the Python-Console of QGIS and I have an object form the class QgsRasterLayer. I want to get the indices of those pixels that have certain pixel value (e.g. I need the indices of all ...
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42 views

Concerning “Error when using r.series in a python script”

Based on the "Error when using r.series in a python script" discussion (Error when using r.series in a python script) and based upon the solution given by Joseph I tried to make the same but by using ...
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1answer
29 views

How to interpret cell size arcgis

I have a raster layer that has cell size(x, y) 0.008928, 0.008928. I download it from the website as 1km resolution data under WGS_84. I can not find the unit for these numbers in the metadata. Is ...
3
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108 views

Converting Road Lines to a Binary Raster Image

I got road data from the USGS database and imported it into QGIS. And I want to transform it into a binary raster image that looks like this in QGIS (this is only a processed screen shot but I want ...
3
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1answer
23 views

Deleting rows from attribute table for large raster file using ArcGIS model builder

I'm not super familiar with raster datasets, so I may be making this too complicated. I have a large vegetation type raster that I need to convert to a shapefile. When I do raster to polygon, the file ...
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17 views

How to resolve issue with model output in degrees and ASCII format cell size in meters when converting to a raster?

I am new to using Arc. I have data from a model output where each grid cell is 1/16 of a degree resolution. I have put the data into ASCII text format, however the header for ASCII under "cell size" ...
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31 views

ArcGIS 10.3 suddenly not reading .tif/.tiff rasters [closed]

Anyone ever experience losing the ability to access .tif/.tiff rasters in ArcGIS/ArcCatalog? Both geotifs and general imagery tifs have become unusable, one day after I was able to access and use both....
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37 views

How to store large time series of raster images

I've got a large time-series of rasters, derived from satellite images. Each raster is about 2000 x 2000 pixels, and I've got about 10,000 individual images. I'm trying to work out what the best way ...
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24 views

DEM from Google Earth, Natural neighbour fails

Does anybody know, why using the tool Natural neighbour fails, when trying to get raster from shape? I followed the instructions here: https://www.youtube.com/watch?v=bLbY3iMBW-A, but all I get are ...
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27 views

Merge village level shapefiles by sub_district_ID to get a new shapefile using R

I am new to using R for manipulating shapefiles and need help with merging the areas inside the shapefile to a superset based on the sub_district_IDs and get a new shapefile.
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37 views

How to build a raster (population density) dependend diagram in QGIS?

I'm using QGIS and trying to solve the following problem. I got 2 layers: 1. population density raster 2. point layer with the information about number of people could be hosted/served etc in this ...
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34 views

Average raster to single value in ArcMap

I need to shift a raster a small bit. I got the distance and the direction using the path distance and cost path tools. I walked into two problems. I have a raster with distance values. I want to ...
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30 views

Bands Names QGIS when merging rasters

I have downloaded landsat satellite data, then I merged the 4 bands I am interested in into one file (raster-merge). The problem is that I merged bands 2,3,4 and 8, and in the merged file the bands ...
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8 views

Rasterize all layer attributes with gdal.RasterizeLayer

I want to rasterize a layer and to have a 2 bands raster in output where the first band is the first feature of the layer and the second one represent the second feature. I tried that but i have an ...
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24 views

Reprojecting multiple rasters in ArcGIS Desktop?

I have classified layers of Landsat 5 and 7 of several years in Geographic coordinate system WGS84. To reproject this to UTM, is there a simpler way than using Project Raster tool in ArcToolbox?
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28 views

How do you convert a raster of digital values of ndvi to an index of NDVI?

I have a raster of the Mean May Normalized Difference Vegetation Index (NDVI) that is a composited measure of VGT daily images, acquired between 2000 and 2009 in May, using the Mean Compositing ...
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41 views

Correctly querying a raster mask only

I have a rasterA (whole Scandinavia, with values from 0-255) and a rasterB (in blue, a small part of south of Norway, entirely inside rasterA). I want to query the pixels of rasterA which are inside ...
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clipped raster but attribute table not updated?

I have a nightlights raster file of India, and I clipped it using the block shapefile for India. After the clipping, the clipped raster files have the attribute of the original raster file. I want the ...
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2answers
44 views

How to make mosaic automatically from quadrocopter photos?

I have many aerial photos (not georeferenced) from a quadrocopter and I want to make a mosaic from them, but it takes so much time. Could you help me with this problem or give me advice on programs ...
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23 views

How do I make a grid around all my points, and then convert it to a polygon [duplicate]

I want to make a grid around all my points, convert to a polygon and use this to clip the extent of my data. I am using Arc 10.2. How do I make a grid and then convert it to a polygon? Or is there a ...
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28 views

Interative raster with PostGIS

I'm searching some solution to show raster layers from PostGIS on a Web Page. I need a solution to build a interactive map showing the values of my raster data when the user to click on pixel of the ...
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23 views

R - `rasterize` of polygon fails to properly take account of internal hole

I'm trying to use R to mask out a DEM raster using a polygon (loaded from a GML shape file) using the following code, where dem_modern is the raster and modern_land_shape is the vector polygon : # ...
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11 views

Alignment in ST_Intersection with PostGIS raster

Trying to intersect two rasters, but they don't have the same scale. I have to do everything in one query. The query below gets the following error: The two rasters provided do not have the same ...
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1answer
24 views

How can I use ST_Intersection with two rasters?

I need to query all values in raster A which intersect with raster B. Found this, but it's not accurate, and I'm getting ERROR: column reference "rast" is ambiguous. WITH first AS ( SELECT id, (...