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

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QGIS 2.10, csv points to vector grid

I have a series of point data from a .csv file that I would like to display as a heatmap raster, the .csv data have various attributes with them and I would like to adjust the color ramp based on ...
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27 views

Free open satellite or other remote sensing data for night time?

I usually work with daytime satellite images to do some image classification (mostly Landsat data from the USGS EarthExplorer). Right now I'd like to check at some night time images to work on city ...
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How to export a polygon based on elevations using a DTM or a DEM

I have a Lidar generated DTM and a DEM (accurate to 10x10 feet). I am trying to export a polygon within a boundary which includes all elevations below a specific number. Seems like this should be ...
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Referencing a raster by center coordinate

I'm concerned with producing mosaics from UAV thermal IR video frames. I exported several several frames containing the temperature values in a matrix (.csv). From camera specifications and flight ...
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1answer
16 views

How to use the hml <area> tag together with Openlayers 3 raster layers?

In order to include interaction to my Openlayer 3 raster layer, I would like to use something similar to the html <area> tag (http://www.w3schools.com/tags/tag_area.asp). The aim is to click on ...
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32 views

Mosaic Imagery using GDAL Edited

I have a couple of large sets of imagery I need to mosaic using GDAL. The sets are currently in tiff format with 18 tiles totaling about 20gb in size. I have attempted to mosaic using both the ...
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22 views

QGIS display wrong histogram statistics for float32 raster

While trying to display a float32 raster created with TauDEM, QGIS displays a min/max of 1,1 although the .aux.xml file contains the correct values. I am using QGIS 2.10.1 both on Windows 7 and Mac OS ...
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37 views

count band numbers from multiband raster image

My raster image has 10 bands (10 bands are 10 year), cell values of each one are 1, 2, 3. One is negative anomaly, 2 is no change area, 3 is positive anomaly. Now I want to find how many years out of ...
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13 views

Segmentation and Classification in ERDAS

I have segmented an image inn erdas and will want to use it in a classification exercise, how do i proceed? My image is a low resolution 30m alos.
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6 views

Help with Raster files and Colour ramps [on hold]

(A)I wonder if there is any general help with Raster files for QGIS? I am encountering some problems related to GRID files that have attribute tables attached in Arc but the attributes don't show in ...
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30 views

C++ code and ArcGIS Button

I have some code in c++ that used gdal and process raster and create an output raster. I want to create a button in ArcGIS Desktop (using ArcObjects SDK 10.2 c#) and pass the raster layer to my c++ ...
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1answer
20 views

replace raster cell values with values in a .csv

I'm looking for a simple way to replace the value field in GRID format with values that I have in a csv. It would be much like doing a join, where the GRID and the csv have a FEATUREID and then ...
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How to combine two different raster by replace its raster value at their overlap space? [duplicate]

I have two different raster data : First data : Second data How to combine those raster data? so the output data will be like this : Where the overlap space between First data and second data ...
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multiple attributes in csv file to raster

I have a several large comma separated text files each with multiple attributes. Each text file is about ~2.9 GB with 21 million lines. Each line contains X, Y, VALUE1, VALUE2, VALUE3, etc. The X and ...
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22 views

Is QGIS aspect analysis description mistaken?

I've been checking the Aspect analysis tool and several sources indicate that aspect is measured from 0 to 360, starting North and going counter-clockwise. Nevertheless, I've been testing it on ...
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12 views

Custom data source for GeoServer raster image

I'm working on a project where a custom binary data file contains latitude, longitude, and temperature data. I'm interested in creating a DataStoreFactory plugin to enable GeoServer to load this ...
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2answers
57 views

PostGIS polygon clip inaccurate using ST_Clip and ST_Union from tiled raster

I have a RGB raster tiled at 128x128 in PostGIS enabled database. I am trying to clip from the raster using a polygon as follows: SELECT ST_AsGDALRaster(rast,'GTiff') FROM ( ...
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IRasterLayer background transparency in C++ with ArcObjects 10.x .NET

I have a georeferenced IRasterLayer which is displaying data with no alpha channel. I am trying to specify a color which should be treated as transparent. In ArcMap it is possible to set a specific ...
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2answers
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Changing raster calculation values - shorten this script?

i'm doing something quite straightforward regarding raster algebra but am struggling either to find the correct function or make a function work correctly; Basically I have 2 rasters, representing ...
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Converting large rasters to NumPy

I have a geodatabase that contains a large number of raster datasets - there are two rasters for each country in the world, and they are very large, in some cases up to 3GB per raster dataset. I ...
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15 views

Reclassifiy raster in R [duplicate]

I have a raster file which has been classified from 1 to 255. I have to reclassify into binary form where 1 to 11 must be classified as 1 and the rest must be 0.How would I be able to do it in R. My ...
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20 views

export several rasters from grass

I'd like to export 127 raster files from grass to .tif in one operation. I already stumbled over this post How to batch export using r.out.gdal command in GRASS but it doesn't work (I don't even know ...
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1answer
27 views

Rasterization of point vector in QGis: how to align the resulting raster to an existing one?

I have a point shapefile, with no associated .prj file, that I have to rasterize. Each point should be transformed into a pixel of 30x30 size aligned to the pixels of a Landsat image (the point file ...
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Is QGIS Server working like this?

On CentOS 7 I have QGIS Server and QGIS Desktop installed. In QGIS Desktop I created a project with raster and vector data and saved it in a ".qgs" file. Then I copied the file in ...
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QGIS GRASS raster to GeoTiff

First of all: Windows 8.1 QGIS 2.8.2 Wien My problem is that I used the GRASS module r.watershed to delineate watersheds and get flows with a DEM. It worked fine so everything is OK so far. But ...
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Using Terrain Profile plugin with an interpolated raster

I am very new to QGIS and the goal of this exercise is to view an elevation profile of a river from a set of discrete points taken from surveying records. Steps taken: A vector layer was created ...
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20 views

Subset moving window when using focal on raster in R

I have a classified Landsat image, and I'd like to pass a filter over it converting certain cells to 0. For some categories, I'd like to set cells to 0 unless an entire 7x7 window contains only that ...
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17 views

Achieving consistent RGB Composite Settings using ArcPy?

Does anyone know if there is an arcpy tool so that when I bring in raster imagery (Specifically Landsat) into ArcMap it will automatically adjust the settings of the RGB composite? I know under ...
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26 views

Combining several mask rasters to obtain one single mask with binary values

I have a series of separate rasters which represent the cloud cover over the same area but in different months. Each raster has 2 values: nan for "no cloud" and 255 for "cloud". What i want to do is ...
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39 views

How to find details to NASA's "Earth’s city lights” images

I am currently working with these images. To find the resolution etc. is simple. But how to find in what units are pixel values? Or any additional details for "how to cite" these images?
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3answers
208 views

Benefits of *.las vs *.xyz or *.ascii when working with LiDAR in ArcGIS for Desktop?

From time to time, we use lidar data for modelling in arcgis. Previously, we would be supplied either an .xyz or .ascii of the data, but more recently, we are also being provided .las files in ...
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1answer
27 views

Expanding raster extent with ArcPy?

How can i expand extent of a raster image with Python as the image shown in below. I have the coordinate information of a raster image such as Xmin Ymin Xmax Ymax,how can i expand its extent based on ...
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Generating polygons based on georefernced Raster image

I have an aerial imagery of a crop field, each of these polygon-looking-group-of-crops-together is called plot. I need to make a polygon shapefile that overlays on top of these plots in the image. I ...
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42 views

Segmentation fault while writing an output raster by blocks with rasterio

With the answer on my previous question, I was able to set up reading a raster by blocks. I did some computation and now I try to write the result into another raster. However, the program fails with ...
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2answers
42 views

Create a raster with ranges from another raster

I have a raster that contains values ranging from 1-180. I am looking for a way to create a new raster where if the values of a cell in the original raster is between 1-10 the new raster cell gets the ...
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Project Raster: Resampling

Is this (optional) resampling technique in the Project Raster tool only being used if changing the grid resolution (cell size)? Or should I always select bilinear (or cubic) for continuous data even ...
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comparing raster values over one specific transect

I have a raster with water temperature data. I used various kinds of filters over it (smoothing, sharpening filter etc.) in various combination. I want to compare the results, to check which ...
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1answer
148 views

Same Raster but different min/max in ArcMAP and QGIS

since I am abandoning windows to stay only with Linux, I started learning how to use QGIS. So far so good. However, trying to reproduce a python script from Arcpy to PyQGIS I noticed something. When I ...
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1answer
138 views

Is it possible to read raster files by block with rasterio?

I find rasterio much easier to use that plain ogr/gdal, so I'd prefer using it. However, I need to process large rasters, so reading rasters by block as explained in the Python GDAL course is ...
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1answer
24 views

Convert Shapefiles into Raster — C++

I'm coding an algorithm which uses as an input a map from QGIS. The software has been implemented in C++ and my idea is to convert, automatically, a shapefile into a raster one. Is there any function ...
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1answer
17 views

Intersection of two vector tables data in postgresql

I have satellite raster data is converted in to pixels using create table gtru_tile_pix as SELECT (ST_PixelAsPolygons(rast)).val, (ST_PixelAsPolygons(rast)).geom FROM ...
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Raster memory usage in R

I am working with raster/brick data in R and running into memory issues. I am basically trying to use raster objects to perform some simple agent-based modeling, but the objects keep increasing in ...
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137 views

Extracting the pixelwise proportion of classes of a finer raster in a coarser one

I have two rasters, one has a 1 km resolution. The other has a spatial resolution of 30 m. This latter pixelwise is a classification. I want to overlay the 1 km raster on the classification raster and ...
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26 views

Is there a “1-band color raster color table” plugin substitute for QGIS 2.10?

I'm currently using QGIS 2.10 and I'm having some difficulties with creating color tables for raster files. I've been looking for the 1-band color raster color table plugin or something similar but ...
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1answer
24 views

r.report giving only per-class cell count

I'm trying to extract the count of each pixel value in a raster, like in this question: How to extract pixel value counts from a raster in QGIS? However, when I run r.report (from QGis (2.10) ...
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How to tell if map service is fully vector or raster?

sorry if this is a duplicate, but I was wondering how to tell if a map service (in web browser) is vector based or raster based? What I think to understood so far is that Google Maps for example is ...
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Snapping raster grids in R

I am trying to align two raster grids in R. Once aligned I would like to be able to add them together. I have tried to check whether making a stack would work: grid_snap <- stack(habi_sdw, ...
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Save raster to file when using stack() in R

I'm working on a function for raster package. In the end of the function I have to use stack() to create a RasterStack. When I do this the data source is in memory. I want to have the data source on ...
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1answer
29 views

How to extend a (river water level) raster, transfering its values to the added area?

Exploring the raster tools in QGIS and related software, I found raster buffer functions to surround existing rasters. The values of the raster buffer are restricted to be distances from the interior ...
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Georeferencing google earth historical images

I have been trying to raster and georeferenced an historical set of images from Google Earth but I am experiencing issues after done the first one properly. I save 4 images from Google Earth of the ...