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

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14 views

Quartiles from Raster Layer band

I'm building a plugin from QGIS, and I need to extract the values from the quartiles from a band in a raster layer. Does anyone knows how it is done?
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19 views

Read GeoTiff from memory in GDAL

Is it possible with the GDAL library to read an image (e.g. GeoTiff) from a memory stream, like stdin instead of a defined location on the local disk? It would be useful to read data in streaming ...
2
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28 views

How to get 4 values for different Indexes and names of rasters for set of points? [closed]

I am trying to get 4 values for different Indexes and names of rasters for set of points, but get problem with defining function def extractIndex(raster, pathName). #List of Folders 4 Folders ...
2
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1answer
48 views

Why do “stripes” appear on raster?

I am reprojecting a SRTM 3 arc-second raster file from WGS84 geographic coordinate system, to projected coordinate system which is using Azimuthal Equidistant projection: gdalwarp -s_srs EPSG:4326 ...
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1answer
37 views

csv points into raster using R

I have got the forest cover data of a region in africa (raster layer) and some data collected inside this region by a survey (.csv). In the .csv file I have got x,y coordinates and 3 other columns ...
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2answers
38 views

Can raster maps be stored in a SQL Server spatial database?

Can raster maps be stored in a SQL Server spatial database? And if so, how? ... I'm aware of VARBINARY and FILESTREAM for images, but can only see GEOMETRIC and GEOGRAPHY for vector data
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1answer
84 views

Writing result of PyQGIS to shapefile

I try to perform some zonal statistics on a shape- and rasterfile and write the output to a completely new shapefile! import sys # where is the module ...
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1answer
21 views

How can i project a coordinate system for many rasters all at once? [duplicate]

help many rasters i have and should be projected in UTM coordinate system. what should i do?
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21 views

Percent overlaying [duplicate]

I have a raster dataset of points and a polygon features. The two are over the same area and I am trying to find the percent of the raster that overlaps the polygon features. I have tried clip, ...
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13 views

Use SVM to make prediction based on two Raster input in R

Right Now I have two raster images, one is elevation another one is slope. And I already generate a SVM model in R. Right now I want to use this SVM model to make a classification prediction using the ...
0
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1answer
39 views

Intersection of a raster and polygon in ArcGIS 10.3

I have two data sets one raster and one polygon. I am interested to see learning the area where the two overlap. I was thinking that I could use the intersect function, but since one of the layers are ...
3
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1answer
41 views

unexpected output from raster calculator function

Working in ArcMap, I am trying to convert the logit values in raster into their actual probabilities (logistic regression,) using the following function: 1/(1+Exp(-"sn_topo_poly_log")) Ive used this ...
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1answer
58 views

Remove/subset raster bands in Python GDAL

I'm trying to remove bands from a raster I have. Basically I just want the first band as a new GeoTIFF file. Here is my code so far: #!/usr/local/bin/python from osgeo import gdal # Load my GeoTIFF ...
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53 views

GDAL_merge - Stacking Files - Nodata Value wrong

I masked a large raster stack by separating the stack in 18 chunks, masking each and writing each chunk to a file (due to memory problems). Then, I use gdal_merge to stack the 18 GTiff files. All ...
2
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20 views

Creating a reference raster in R

I need to create global reference raster (100km grid, Eckert IV). Later, I will project other various rasters (with different resolutions and projections) into the resolution/projection of the ...
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44 views

How to get NIR values into a LAS file then a CSV?

We are trying to deliver a LAS file with NIR values added for each point. The NIR comes from a raster captured at the same moment as the LiDAR, and is stored as an 8bit number along with RGB in 8bit. ...
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18 views

problem with raster calculator syntax [closed]

I am trying to build a raster representing the output from a logistic regression model. i keep getting syntax errors. heres the script: -2.41-(15.97 * "Topographic_Predictors\wadem10m_annsolrad") - ...
2
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1answer
34 views

Raster rotation on QGIS

How can I rotate a raster layer (global land-mass) to make the 180 deg longitude the center of the map (using QGIS)? 'rotate' function in R is simple but not accurate. Raster has 'longlat' projection ...
0
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1answer
46 views

Creating raster image using Shapefile in ENVI?

I have shapefile containing polygon boundaries and want to change them as a raster image in ENVI 5.3. Although, this could easily be done in ArcMap or other GIS software, however, I will have to ...
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1answer
41 views

QGIS Script Editor to get operations between raster and float number

I am looking for developing python codes mainly for working with raster data, in particular satellite imagery from Landsat. I need to write a script (into the QGIS Script Editor) to make operations ...
0
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1answer
25 views

Combining data in two projections?

The PAMAP dataset comes divided between two different projections: Pennsylvania North State Plane and Pennsylvania South State Plane. I'd like a great big DEM of the whole state of Pennsylvania. ...
0
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1answer
22 views

Add a random value of the order of 10^-2 to raster layer?

I was doing some raster analysis for smoothing in ArcGIS, one of my task is adding a random value of the order of 10^-2 to a raster layer. Does anybody know how to do it?
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1answer
52 views

Resampling a raster file with GDAL C#

Is it possible to resample the raster by using GDAL C# binaries, in a way that every other cell in a row and column is removed? Basically a replication of this GDAL command: gdal_translate -outsize ...
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2answers
53 views

R: creating an error matrix from two rasters

I have two land use rasters (6 classes each) and I'd like to create an error matrix (errors of omission and commission) from them both. The premise is that I have a very fine 'base' raster and have ...
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14 views

Raster Values converted to 3.4e+38 in R

I have read a .grd file into R as RasterLayer which should only contain 1, 0 and NA as cell values. Turns out all the NA cells contain 3.4e+38 as value now. How can I change that and why does this ...
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3answers
130 views

Reproject raster with FME

I have multiple .tiff + .tfw files in EPSG:3067, which I need to reproject to EPSG:3878. I tried to do it with FME, and succeeded, kind of. The geotiffs are placed well, but some weird white area ...
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10 views

How to divide bitmap into differnet layers by RGB color code in MapInfo

I have got bmp file with 7 colors. How to get from this bitmap 7 different vector layers depending on RGB color code? For example first layer is water space with blue color, second is buildings with ...
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17 views

Mapserver raster tiles have wrong colors on zoom

Displaying a raster via MapServer on OpenLayers-3 webmap. When zooming in, the resampling or something is behaving weirdly and the colors become very distorted. See image below, the bad tiles should ...
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24 views

Need to compute fragmentation indices within discrete zones

Running arcGIS 10.3 (also have the latest QGIS), win7 64, workstation 16g ram and an intel xeon processor. I'm preferably looking for a simple turnkey solution; very little python experience. ...
2
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1answer
35 views

Determining hardware requirements for mosaic dataset operation to work properly?

I've been building mosaic datasets in ArcGIS, but have been having mixed results depending largely on the number of cores on the computer being used to build the mosaic dataset. For example, on a ...
2
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1answer
39 views

Export google satallite raster in QGIS 2.12- problem

When I import aerial raster from Google satellite, using the OpenLayers plugin the raster is located in the right place. But when I export it the raster isn't located in the right place: I ...
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35 views

Raster package limitations

I am very new to R and to raster package and I was hoping that someone could provide some guidance. I am trying to run a function that averages a series of rasters, 300 to be exact, they are in geotif ...
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36 views

how to load raster image in leaflet? [closed]

I want to load a raster base layer in leaflet because the base layer usually needs an internet connection I want to load the raster offline .
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46 views

Python error in Qgis 2.14.0

I'm trying to build virtual raster (catalog) following instructions from the documentation in QGIS.. It appears the following error in python code: 2016-04-17T12:13:07 1 Traceback (most recent call ...
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8 views

Using IDW method and its output raster in a web app

I am creating an web app and needs to interpolates between some points- Weather data- (with IDW method) and show the results as a raster (like the output from ArcGIS) so a user can click on raster and ...
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21 views

Extract raster values from RASTERSBRICK using XY coordinates falling within each polygon R

I have a rasterbrick s (10000 raster layers) that actually is a time series raster. Accompanying s is a SpatialPolygonsDataFrame with many sub-polygons which can be identified by names and/or IDs etc. ...
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62 views

Slow performance clipping raster with GDAL

I have a few large LiDAR DEMs that I want to merge. Each DEM has some glitches around the borders which need to be removed in order to get a seamless final product. I manually traced around each DEM ...
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25 views

Curve Number equation

I have a floating point raster of Curve Numbers (70-91) and I'm attempting to use the curve number equation to create a weight raster for flow accumulation, to determine runoff for a single rainfall ...
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18 views

Finding regions or zones in raster DEM of similar slope or aspect values in ArcGIS for Desktop?

I have a detailed 5m DEM for my study area. I want to find regions or zones where the slope or aspect (or preferably both) varies little. In other words, a nice evenly sloped hillside with a ...
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18 views

Reduce raster resolution and determine pixel inclusion based on % pixel overlap

I'm trying to reduce the resolution of a raster from 1m to 50m using a pixel aggregation (average) method, but I need to set a threshold for inclusion (e.g. 75% of the 1m pixels must fall within the ...
2
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0answers
46 views

Draw raster on top of a Leaflet map

I want to implement a raster layer on top of a Leaflet map that includes the following functionalities: Digital Elevation Model (DEM) terrain height included in each raster cell GPS-Track (I use ...
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2answers
28 views

Issue running r.region in GRASS command line

I'm currently attempting to use r.region to preform analysis on a specific area of a raster image. I'm receiving Lat/Long data from the step before me, but I'm having issues use that data in ...
0
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1answer
28 views

Calculating the number of days above freezing in R

Im wondering if anyone has come across any data source that can be used to calculate the number of days where temperatures are greater than 0 degrees C, 10 C and 20 C at a global scale? I have a site ...
3
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1answer
72 views

Export raster layer in python to specific folder

I am trying to export existing raster layers as tif files. I just want to avoid saving each raster manually. this is the code I am trying to use, but it doesn't seem to work: from PyQt4.QtCore import ...
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2answers
29 views

Add raster attribute table to raster using arcpy

I have downloaded US soil raster data by state from https://gdg.sc.egov.usda.gov/GDGOrder.aspx at 10m resolution. I am now trying to add a modified raster attribute table to tif that was exported ...
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2answers
39 views

Arcpy Reclassify by Standard Deviation

I would need some help with the Reclassify tool. I have written a script that produces rasters which I need to reclassify. My problem is, I want the values to be reclassified by standard deviation ...
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16 views

How does “Mosaic to New Raster” tools works? How does it treat pixel values?

I'm working with arcGIS. I have mosaicked 8 rasters with values ranging from -408 to 180. The new mosaic shows pixel values ranging from 0 to 180.Then I compared cell by cell values from the original ...
2
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1answer
44 views

Merging and splitting raster files in QGIS

I have four .HGT topography tiles (tile1,tile2,tile3,tile4 in the photo below). They are in geographic coordinate system. I would like to merge those four tiles, and then from that merged raster layer ...
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1answer
28 views

Fix AttributeError in python code

I got some code that I think should work, but I'm getting this error: Traceback (most recent call last): File "", line 1, in File "c:/users/proxtr~1/appdata/local/temp/tmpgtrnqo.py", line ...
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0answers
37 views

QGIS raster style rendering incorrectly/unexpectedly

I have a raster of flow accumulation. To style it, when I set manual values for raster breaks in qgis 2.14 it isn't rendering all values below the value I set in the same colour. My understanding is ...