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

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Can I use georeferenced jpeg raster as map layer in GeoJSON.io?

Can I use georeferenced .jpeg raster as map layer in GeoJSON.io? I thought that I could, but it doesn't work. I converted .tif raster visualization of LiDAR data to georeferenced jpeg. After this, I ...
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24 views

Clipping a Raster

i m facing a strange problem. i created a mosaic of two landsat scenes. it contains values from ~ -5 to ~11 (Biomass estimation). As my Studyarea is much smaller then the mosaiced Landsat8- Scenes, i ...
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3answers
40 views

Create continuous raster from point values in 10.1?

I have a point dataset of nearly 400 points containing percentage values of cost total for the site the point is representing Is there a way to create a smooth continuous raster surface across the ...
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4 views

Raster cleanup eraser fail in ArcGIS for Desktop?

I am running ArcGIS 10.3 ArcScan and trying to clean up a raster prior to vectorisation. The raster was a three band raster converted to greyscale using the 'Greyscale function', classified into 2 ...
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2answers
23 views

How to efficiently extract time series from a very large multi-band GeoTiff in R?

First some context: I want to run a time-series analysis function that is only available in R for a continental sized multi-band time-series raster, which is stored in disk in GeoTiff format, that was ...
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1answer
20 views

In R's raster::terrain function, which way is north?

The terrain function in R's raster package calculates slope and aspect from an elevation raster: see http://www.inside-r.org/packages/cran/raster/docs/terrain. With the unit="degrees" option, the ...
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23 views

Calculate exact percentile for each rastercell and create new raster with percentile values [on hold]

I need to calculate the exact percentile value of each raster cell in a raster layer, in order to create a new raster layer with this exact (decimal) percentiles. (In excel this function would be "...
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11 views

Single value of raster displays as transparent?

I have a GeoTiff raster that I'm trying to style, but a single value (1 of 8) refuses to take on any color. It always displays as transparent. Any idea of why this is / how to resolve it? Working in ...
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9 views

Raster to CSV with x y cell center coordinates, the original raster cell value, and values from another raster avoiding shapefile

I am looking for FOSS (maybe GDAL/OGR) solutions to a problem. I need to go from raster (200 million records) to CSV. It is easy enough to do via point but the point file breaks the allowable 2GB “...
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1answer
60 views

Drawing concentric circles that correspond to free space loss formula?

I want to be able to draw a circle with 50km radius and then fill the circle with values corresponding to the free space loss formula below: FSPL(db)=20 log10(d)+20log10(f)+32.44 for example: a ...
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1answer
26 views

How to resize a raster SUMMING the values of pixels in QGIS?

I would like to be able to resize a raster such that the values of the resized pixels are based on the SUMS of the original raster pixels, rather than the averages. The output should be generated thus:...
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14 views

dismo::randomPoints generating fewer points than requested in R

I'm using the randomPoints function in the dismo package to generate sets of point locations within two polygons. I've converted the polygons to rasters, where the cells within the polygon = 1, and ...
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1answer
28 views

Self-hosted web app to view raster & vector layers and annotate

I'm trying to find a self-hosted web app that allows you to view a number of raster and vector layers on a draggable web map, and then to 'annotate' the map by adding points to the map with associated ...
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0answers
12 views

Rescale raster files in QGIS

I want to construct a surface of predictions in QGIS, using several probabilities I otained previously in R, by constructing GLMM. But I rescaled my variables before constructing GLMM, so I also need ...
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21 views

Land cover generation

I am working on a river watershed on QGIS and I need a land cover map. I have a good raster of land use data with 15 m resolution for year 2015, but it covers around the 90 % of the basin. I have ...
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1answer
21 views

Why are high and low elevation values different than individual files when using the mosaic tool for DEMs in ArcGIS?

I am attempting to mosaic 7 SRTM files. However, the mosaic I have created has values higher than the highest elevation (4022) and lower than the lowest elevation (-89) of the individual files. The ...
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0answers
27 views

Looping extract by mask from raster list using ArcPy gives ERROR 99999? [closed]

I am getting an error when I try to iterate raster files through the extract by mask tool. I am running ArcMap 10.2.2 and the Arcpy script I am try to use follows: # Import arcpy module import arcpy ...
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1answer
38 views

Recording height profile from raster along a polyline shapefile?

I'm looking for the easiest way to record a series of raster values along a 400 meter transect in ArcGIS 10.3.1. I'm working with a LiDAR canopy height model with 3mx3m cells where each cell ...
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2answers
21 views

ArcGIS Online - Need to upload lots of raster files/georeferenced maps. How?

The end goal is to build a web application where people can explore the historical maps I've georeferenced - among other things. ArcGIS online is the ideal venue for everything else I want, but for ...
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1answer
30 views

Applying symbology to raster layer in ArcPy without using symbology layer (layer file)?

I have a raster layer with 3 unique values (1,2,3) and I want to apply a unique color to each using RGB values or hex codes, without the use of a symbology layer (layer file). Is it possible to ...
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7 views

Using predict function in raster package for applications other than species distribution modelling?

I was wondering if the species distribution modelling technique can be used to analyze other variables such as human movement. For example I have data on whether a person attends a facility (binary ...
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14 views

Problem in cell dimension assignment from “save as” in QGIS

I am trying to save one raster in QGIS by changing the cell dimensions. I select 30 x 30 as cell resolution, but then the output raster has a resolution of 29.9985 x 29.9985. How can I assign exactly ...
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1answer
14 views

Extract lat long point values from EASE2 without reprojection

I have the following file: EASE2 and want to extract the values for this geographic location (148.1, -35.6) #lon lat. How can I do this without the need for reprojecting the ease grid file into ...
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2answers
48 views

Precipitation data raster

I'm using the TRMM 3B43 precipitation data. I have downloaded individual NetCDF files depicting yearly accumulation in mm for each year from 2000 to 2015 (16 files). I have imported each file into ...
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1answer
20 views

How to access to the underlying grid table behind Mapinfo's Grid Thematic map?

I created a grid thematic map using "Mapinfo - Map - Create Thematic Map" function. Now I want to know the distribution of the data from the grids. But the "Browse Table" option is not functioning ...
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24 views

4 sequential Landsat image cant be merged into one single file, in QGIS. how to solve this issue?

i am trying to create land-use, land cover classification by QGIS. i have Landsat images downloaded from earth explorer. these are *.tiff files. but my region is not covered by single pic. thats why, ...
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2answers
18 views

Problem with r.grow.distance on GRASS

I would like to use r.grow.distance on a raster map. I rasterised a shapefile (about 50 cities in a region) and we can see them on the raster map. Yet, when I launch r.grow.distance, I have a ...
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1answer
31 views

Sum area of specific poly attributes within raster grid cell

I have a polygon layer (A) containing several different land use types (road, building, etc). I also have a different GIS layer (B), a raster of NLCD land use/land cover. I would like to sum/...
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1answer
19 views

Can a Mosaic Dataset have rasters with different vertical units?

I am creating a Mosaic Dataset (ArcMap 10.3) that contains LiDAR dems from a number of different US states. The data is in different coordinate systems (UTM, State Plane meters, State plane feet), ...
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4answers
107 views
+50

How to efficiently access files with GDAL from an S3 bucket using VSIS3?

So, GDAL has recently added a new feature that allows random reading of S3 bucket files. I am looking to crop GDAL images from multiple tiles of an image without having to download the whole file. I'...
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11 views

kernel density estimation-mask layer-arcgis

I have a vector layer with points (road accidents) and another polygon layer which is the area in which occured these accidents. I ran kde where I changed the environments-raster analysis (I added as ...
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1answer
10 views

r.statistics throws invalid reclass rule error despite assigning null to unique value

Trying to run r.statistics on two raster layers, one a layer of distinct zones produced via r.clump (stands) and one a layer of all ones (ones). The areas outside of the immediate region of interest ...
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21 views

How to create raster layer directly from numpy array in QGIS, without saving to file?

I have managed to create a numpy array from a raster file using commands from the gdal library, and now I would like to load that raster as a layer without saving it first. It seems like there should ...
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1answer
88 views

Max value of overlapping Polygons

Licence: Advanced Version: ArcMap 10.3 In my shape are thousands of overlapping polygons. My goal is, to generate a new output in which the biggest overlapping value represents a new polygon/...
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1answer
40 views

How to make a loop that interates over large raster cells in R go faster?

I am trying to add +1 to the cell value of certain cells in a raster. I have the cell numbers of the cells on which I'd like to perform said computation saved in a vector. I have a working code but ...
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2answers
46 views

How can a statistically significant difference between rasters be calculated?

so after some gruelling use of MaxEnt I have four occurrence probability rasters for the four quarters of the year, each one is about 70MB+. I want to test whether they are significantly different ...
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1answer
38 views

Rasterizing in R - how do resolutions work? (e.g. population within a circle)

I'm creeping into building surfaces - useful for a number of public health projects - and can't seem to make sense of what's happening with the resolution and raster building process to get what I ...
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15 views

Resolution changes when exporting raster from GRASS to Arcmap

I have a raster file of rainfall (floating) in GRASS that I want to export and open in arcmap. If I look for the raster file in GRASS, it has Rows: 140 ...
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0answers
21 views

Scanning a raster by moving windows. Output rasters off by a cell. ArcGIS, python

I'm working in extracting smaller rasters from a bigger one (yellow). I'm using only python, some numpy maybe. I succesfully extracted a patch from a big raster, secuentially, by moving windows. So I ...
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2answers
32 views

How do I convert a fire frequency point shape file into a fire frequency raster?

I have a point shapefile that I want to convert to a raster image using ArcMap 10.2. The shape file has a number of points on top of each other. Each point is a fire. I want to make a fire frequency ...
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0answers
43 views

Why do merged rasters in QGIS look 'patchy'?

Poor title for this question, but I can't think of a better way to explain it. I have merged two rasters. I want the joins to be seamless, but there is an obvious line where they meet... I've ...
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1answer
15 views

Receiving higher values than should be possible in stackApply SUM for Frequency calculation in R

I am currently working on creating a frequency raster for a country based on multiple Rasters of the same day through following years and where the previous values are reclassified to 1's and 0's. The ...
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0answers
27 views

Multiband virtual raster with gdalbuildvrt: Control how bands are sorted

I am making a multiband virtual raster using gdalbuildvrt. Everything works fine, but a little detail remains annoying: I cannot control how the bands are sorted. I specified the input raster using ...
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14 views

Perform supervised classification on SAR image in SAGA GIS

I tried working on supervised classification on SAR data in SAGA. I am confused about creation of training data. How can I create Training data for my SAR image?
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12 views

Calculate Worldwide Raster area (30arcsec, WGS198) [duplicate]

I have a worldwide raster dataset (30 arcsec, WGS1984) with 11 Landcover classes. My goal is to calculate the extension for each class. I´m using ArcMap 10.1.3. So far I projected my Raster in ...
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1answer
24 views

Set projection (netCDF) with R-ncdf4-Package

I want to create a netCDF-file that has a defined projection ("WGS 84 / UTM zone 32N") with the netcdf4 package in R. The input float array has the size of x=880 and y=760. So i define the two ...
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1answer
30 views

PC and Mac treating raster brick input differently in R

All - this is likely an idiotic question, but, I've been working on developing some GIS code in R that interacts with an online source. So, sprinkled in various places, I have myBrick <- brick("...
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8 views

Change index of an indexed color image with a lookup table

i have an raster file in indexed color mode (256 colors). The indexed colors are spread from black to white between the 256 colors. I need to reduce the colors exactly to the maximum of 100 colors in ...
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1answer
44 views

Extracting small numpy array from a bigger raster, by moving windows. Memory issues. ArcGIS

I'm trying to extract a small raster from a bigger one, just using python and numpy (I'm not allow to use any other software). This code just reads a from a big raster, extracts an smaller window, ...
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0answers
12 views

Setting raster values greater than 0 to NA in Saga GIS

I want to set all my raster values greater than 0 to NA in SAGA GIS. I am new to SAGA.