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

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2
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1answer
31 views

Importing large .asc files into QGIS

I've been given two .asc files containing a 1m raster data from a LiDAR survey. I only have access to QGIS.2.14.1 (which I'am using for the 1st time only having previous experience with ArcGIS) and ...
2
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1answer
156 views

Defining the output raster resolution when rasterizing a vector?

I have a vector file which I want to rasterize and adjust its resolution to the reference map, in QGIS. I tried spatial_sync_raster function in R to set all the rasters into the same resolution as ...
4
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2answers
90 views

Identifying individual pine trees without using LiDAR data?

Are there any ways to identify individual pine trees without the use of LiDAR data? Crown identification seems irrelevant. My goal is to do a rough treetop calculation to get an idea of how many ...
0
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0answers
16 views

Recommendation for getting TIF raster from modis HDF, for processing in R

I've downloaded a set of modis mod13q1 HDF files, e.g. MOD13Q1.A2016097.h11v05.006.2016114040325.hdf. I'd like to load the 250m_16_days_EVI and 250m_16_days_pixel_reliability bands into R as rasters. ...
0
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1answer
233 views

What exact format do I need to have for the inputs to make Path Distance work?

I am trying to run the Path Distance tool in ArcGis 10.1. Ideally I would like to utilize Tobler's hiking formula anisotropic approach to slope and a land cover cost surface to calculate the least ...
0
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1answer
38 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 ...
0
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0answers
6 views

How do I display NAD 1927 Albers with other data?

I have some raster datasets which are in NAD 1927 Albers projection. I cannot seem to display any other type of data with this projection. I get the pop-up projection warning when trying to add a ...
3
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1answer
63 views
+50

Krovak projection EPSG 5514: Correct data transfer between R and ArcGIS?

I have a problem which many ArcGIS, QGIS and R users from Czech Republic and Slovakia may encounter. In ArcGIS, I am working EPSG: 5514, Projected Coordinate System, defined as: ...
0
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1answer
206 views

using raster.predict for Cubist model, factor levels list

I would like to thank in advance any help or advice. Let me know if I need to provide more reproducible data/code. I am working on a Cubist prediction model for soil texture, using continuous and ...
2
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0answers
11 views

Issue loading PostGIS out-db rasters (either in QGIS or MapServer)

I'm playing with a few different options of storing raster data via PostGIS to visualize (eventually in a web app). The out-db or out-of-database storage seems the best option, but I can't seem to ...
0
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1answer
21 views

How to merge rasters with the same but unequal cell size in ArcMap?

I'm trying to merge raster tiles that all have the same, but unequal cell size (X: 2,8, Y: 2,9). When I use the Mosaic To New Raster tool, I can enter ONE cell size which either results in a raster ...
1
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0answers
17 views

Zonal Statistic Tool

In ArcGIS, I have a grid 5x5km (I have it both in vector and raster formats) I want to calculate, based on this grid, the zonal statistic (MEAN) of a raster 30x30m pixel size. The raster overlaps ...
0
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1answer
32 views

Exporting Raster from SAGA and importing it to QGIS - error CRS was unidentified

I make raster files from LiDAR las files in SAGA - CRS of .las is Slovenian national Grid. Then i export it as GeoTiff (Import/Export - GDAL/OGR - Export GeoTiff). When i import it into Qgis (Project ...
1
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0answers
19 views

Raster Precision QGIS

I am using r.patch extension in QGIS to join a number of LiDAR tiles, some of which overlap hence i am carrying out this task before utilising in a hydraulic model. R.Patch works fine, however the ...
1
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0answers
19 views

How do I change the pixel values of raster data from QGIS python plugin

I have been trying my hand at a QGIS plugin. The plug in reads raster layer data into an array, pipes the data to a C++ program, does processing over there, and pipes my results back. After a couple ...
1
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1answer
32 views

Generate ESRI grid with xllcenter/yllcenter in header

I'm trying to generate ARC/INFO ASCII GRID (*.asc) from point feature class using Create TIN - TIN to raster - Raster to ASCII functions. I'm looking for a way to have the output raster file header ...
1
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1answer
19 views

Raster to point

I have a raster (5km pixel side) and I want to create a shapefile of points, one point per pixel (like a centroid), each point carring the correspondent pixel value. I run "RasterToPoint"tool in ...
2
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1answer
25 views

How can I calculate the percent of a raster cell covered by a polygon?

First, I am going to try and intersect a raster and a polygon shapefile. I'm not 100% sure how to do this (or if I need to do this for the next step), so if you have any suggestions please let me ...
0
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1answer
282 views

Gridding a LiDAR point cloud? [duplicate]

I have been trying to grid a point cloud, version1.2, LiDAR datasets which are intended to be used for hydraulic simulation of flood propagation. Already, I have used Arc* to work on the traditional ...
13
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10answers
30k views

Get boundary of raster image as polygon in ArcGIS Desktop?

I have a rectangular raster image in ArcGIS. My question is: how can I produce a polygon which is just the extent of the raster image? That is, I want to have a polygon layer with a single ...
-3
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0answers
7 views

configure popups in map service when rasters are added as a layer [on hold]

Can any one explain how should I configure popup for displaying the sea surface temperature and cloud top temperature, when raster layers are added in mapservice
1
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1answer
34 views

Convert a raster with one band into a raster with RVB bands on QGIS?

So yesterday i downloaded a raster tile on a WMS server and exported it with Grass. I get a raster with 3 bands, i treat with the Semi automatic classification Plugin in QGIS and it works perfectly. ...
0
votes
2answers
331 views

Issues calculating range with QGIS 2.0 raster calculator

I would like to calculate a simple range using the QGIS 2.0 Raster Calculator, but am getting strange results. I believe I am not using the correct syntax. To get all values between .003-.5, I ...
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1answer
282 views

Creating an R factor raster in RUSLE Soil Loss equation with multiple input rasters

I am attempting to obtain the rainfall erosivity "R" factor for the RUSLE Soil Loss equation using rainfall PRISM 30 year history data. I have both monthly and annual data that comes into ArcMap as ...
0
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1answer
14 views

How to extract single band from multi-band radiometry raster using R?

I am having trouble extracting single band from multiple multi-band raster. I have no problem doing it on single raster file. Is there a way to loop through all the raster images to extract a single ...
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0answers
27 views

Calculating total area overlapping raster DEM color interval whose boundaries are confined by another vector? [duplicate]

Example: I tried running raster calculator on intersections then zonal statistics checking "count" and "sum" but I get a huge table of 8000+ rows and two columns, however each cell usually have a ...
5
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4answers
132 views

ArcGIS 10.3: Insert rotated image without background

How can I insert this image into an mxd so the white background doesn't show up? I've tried using photoshop to delete the background and save it as a format that supports transparent backgrounds (gif ...
3
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3answers
3k views

using Python to calculate NDVI, output as a Geotiff

I need a script that can calculate NDVI from two separate input Geotiff files, then output the results as a Geotiff. I wrote following script, most of which is borrowed from various on-line sources ...
-2
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1answer
22 views

“First” and “Last” from Global Forest Change [on hold]

What are the "first" and "last" rasters provided by the Global Forest Change data set?
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0answers
20 views

Selecting cells with values from DEM those are above specific value corresponding to each polygon?

i have a shapefile with 2000 polygons and a DEM. i want to calculate zonal mean for each polygon considering values from DEM which are above a particular value for each polygon. i want to it with ...
0
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2answers
49 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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0answers
27 views

map with road boundary ,road markers , intersection, crossing…? [on hold]

I am working on a map with detailed geospatial information of road surface, road boundary, road curb ,road markers , intersection boundary, crossing boundary... and those information extract from ...
1
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2answers
33 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
0
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2answers
22 views

mapping with spplot

This question should be easy! I am using spplot for visualizing a map with suitable results. However, I would like to know how to set the limits of z, because the values are not being discriminated. ...
8
votes
1answer
267 views

Calculate mean value of polygon from raster in PostGIS

I started with a NetCDF .gri and .grd raster file of the UK provided by a colleague. I clipped it in R to be only London, exported and converted to a ASC file, and then imported it to PostGIS using ...
2
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0answers
17 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 ...
1
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2answers
24 views

How to export vector file in GrassGIS to QGIS

I am using GrassGIS to analyze watershed. I created a stream vector extracted from raster elevation data, how to extract the stream vector file so I can open it using QGIS?
7
votes
1answer
378 views

How to store Large Raster Images of Equipotential Surface Generation Using Monte Carlo Simulation?

I have a large (1GB+) raster that I am using as the base for the generation of an equipotential surface. This is to assess the accuracy of DEMs derived from another source. In situ observation is ...
1
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1answer
25 views

32-bit Map tiles for use with leaflet

I've got a lot of single-band Geotiff files with the GDT_Float32 format and I need to present these over the web, hopefully using a webmap leaflet/mapbox/googlemaps widget where clients can hover over ...
1
vote
1answer
265 views

Exporting .tif from referenced mosaic dataset does not use functions in raster dataset

Very frustrating little issue in ArcGIS 10.1 -- I have a referenced mosaic dataset of terrain data that has a series of functions inserted (slope and several iterations of a statistics function to ...
1
vote
1answer
329 views

How to use GDAL to burn a selected value from one raster into another?

I think this should be a relatively simple process, but I'm not quite sure how to approach it. I have a shapefile containing 1000's of polygons. I also have 19 rasters. All of the polygons fall ...
2
votes
0answers
28 views

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

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
votes
1answer
2k views

How to reclass a raster with reclassify grid values in QGIS?

I'm new in QGIS and I'm trying to reclass a raster with reclassify grid values. I want to reclassify by table, however fixed table has only 3 rows and I need some more, but button to add is not ...
0
votes
0answers
20 views

Why ArcGIS crashes when I load raster file created in R? (HFA format)

I was processing my raster operation in R, as I think it's easier then in ArcGIS: - read shp + raster1 - crop them - classify raster1 by location - create classified raster2 - export the ...
3
votes
1answer
25 views

Problem with algebra formulas for work with gdal_calc.py

I'm trying to update some values of a raster based on another raster. 1st raster (A): landuse data (values from 10 to 240) 2nd raster (B): mask data (only nodata values and a given value, for ...
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2answers
1k views

Changing color of raster images based on their data values - gdal

Let's say I have 1 band raster images with Gray Color Interpretation and I want to change their color based on their data values. Data values -1, will be Blue, -0.5 will be Light Blue, 0 will be ...
0
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0answers
29 views

Create a grid over shapefile then save each section into GeoTIFF

I have a massive shapefile with 200,000+ building polygons. I've loaded these up in ArcGIS. I need to convert this into a usable raster (GeoTIFF) that can then be tiled using MapTiler. My current ...
0
votes
1answer
16 views

How to I change the extents of a Euclidian Distance Raster?

I am calculating the Euclidean distance of a set of points. The output raster truncates the resulting raster image to the farthest north, south, east, and west point. I need the distances to extend ...
2
votes
2answers
238 views

Is there anywhere that I can obtain global UV data in either raster or vector format?

I'm looking for some UV data (currently with no spatial or temporal resolutions in mind, but ideally split into UV-A and UV-B) for the whole earth. Can anyone recommend a source for data like this or ...
1
vote
1answer
35 views

Reclassifying raster analysis (like the one in ArcGIS Spatial Analyst) in QGIS [duplicate]

I am trying to reclassify raster (DEM) in QGIS. I know how it is done in ArcGIS (Spatial Analyst, reclassify option), but I would like to know how it is done in QGIS?. The point of my exercise is to ...