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

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Average of raster elevation based on polygon boundaries

I am attempting to extract and calculate the average height of buildings using LiDAR converted to raster elevation data. I've created a DSM to cover the entire area and I am trying to extract just the ...
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How to spread a population data from a vector layer in a raster layer? [duplicate]

I got a shapefiles for provinces in a African country. In each province there is the population data. I've got 3 TIFF (raster), one for the agriculture, one for the cities and the last one for ...
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50 views

Raster processing in ArcPy seems to “simplify”/“round” my resulting values

I'm working off a DEM and doing some raster algebra with it (real simple, add this decimal value, then divide by this value). The DEM in question is super high resolution LiDAR, that's both spatially ...
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21 views

What projections and input file parameters are supported by r.resamp.rst?

I always get ERROR: Unable To Seek after I run r.resamp.rst r.resamp.rst input=map30 ew_res=10m ns_res=10m elevation=map10 It actually starts to work but after it finish I get the error and no ...
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1answer
76 views

Optimizing Python GDAL ReadAsArray

I am using the GDAL ReadAsArray method to work with raster data using numpy (specifically reclassification). As my rasters are large, I process the arrays in blocks, iterating though each block and ...
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111 views

Point attribute from underlying raster data TIFFTAG

I have a layer of manually set points in qgis that have the following attributes at the moment : id, lat, long Additionally, I have a number of different overlapping raster images (sattelite data) ...
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37 views

Clipping raster with polygon for band-by-band output using ArcGIS Desktop?

How do you clip a raster image with a polygon shapefile so that the output is multiple clipped rasters, each one a band (i.e., clipped raster band 1, band 2, and so on)? I've tried the clip tool for ...
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32 views

Assigning spatial info for NetCDF files using ArcGIS for Desktop?

I have quite a few NetCDF files that arrive from a air quality model without any spatial reference. However, I do have the spatial reference information that is required. Within Arc I use "make a ...
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42 views

Count the number of raster tiles in each polygon in ArcGIS

I have a raster from the TRMM 3B43 product that contains a grid of 0.25 x 0.25 tiles (in degrees). I also have a shapefile with a number of districts. I want to know how many raster tiles are included ...
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gdal_translate crashes on huge jp2

I have 44GB jp2 file, I want to translate it to tif file, but once it reaches 10% it crashes. No messages, just stopped. This is my command: gdal_translate.exe -of GTiff --config GDAL_CACHMAX 8000 ...
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112 views

How to download the MODIS data from R using MODISTools library

I want to download MODIS product MOD13Q1 to use the Scientific Data Sets (SDS) layers of "250m_16_days_EVI", "250m_16_days_pixel_reliability". MODISTools library in R software provides the capability ...
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74 views

Convert raster to polygon

Using ArcMap 10.3, I want to digitized only the pale blue polygons in the raster into shapefile with "Raster to polygon" tool. This is the raster: I get a shapefile with gridcode field, but i don't ...
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38 views

GeoServer altering raster values of multi-band raster WCS request

I'm hosting some NAIP imagery (4-band) through Geoserver and while WMS requests show true pixel values properly, if a WCS request is issued, the raster GeoServer returns has pixel values of nodata ...
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44 views

Raster Extrapolation in QGIS?

Does QGIS (or different software) have a method to extrapolate raster values to larger area (outer boundary)? I have a boundary(.shp), which is 40 m far from the edge of raster. I want to fill the ...
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2answers
54 views

Creating a raster file from a shapefile using GeoTools with different colours for different features

The shapefiles that I am processing display information on an operation of a piece of equipment over an area, where the information is stored in steps as polygon features with various attributes and ...
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19 views

Loading rasters using agent analyst

I'm new to agent-based modelling, but have been using GIS for a number of years now. I am trying to create a simple model that shows the potential loss of salmon from a number of locations due to ...
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2answers
98 views

Selecting Polygons that have certain raster data within them

I am using a raster layer with either 1 or 0 in each cell. On top of this layer, I have a European countries shape file. The countries that contain a '1 cell' in the raster beneath are the Countries I ...
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76 views

Improve Slope Raster Precision?

Im working with ArcGIS and i have a raster layer created with just four points in XYZ, the plane that forms between these four points has a slope of 10 percent. When using the tool SLOPE (3D Analyst> ...
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15 views

QGIS world files rather than .xml [duplicate]

Is there a way to get QGIS to write out a world file (.wld/.pgw/.jpw) etc rather than an aux.xml. I see the aux.xml is in general better but it isn't supported by the other software I am using. I can ...
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Points to raster - interpolation

I have a point layer with soil values. How can I get a raster layer with different classes of values, since there are areas without point sampling, what´s the best way to have a regular cover of the ...
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30 views

Converting UTM55 to WGS84 in ArcMap? [closed]

I've got a raster in UTM55 over Australia and I would like to convert it to WGS84. Any idea how to do it ? The problem starts when ArcMap recognize it as 'Geo-Reference' only and not as UTM55, so I ...
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How large is the entire ASTER Global DEM on disk?

I see from various online sources (including GIS.SE's own How to download the entire ASTER GDEMv2 dataset?) that the ASTER GDEM has 22'000 tiles, each 1°×1° and 3601×3601 pixels (each pixel being ...
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35 views

Handling warning about DX and DY in gdal_translate from .Gtiff to .ASC?

When I try to convert Gtiff to .asc file, QGIS shows the warning: Producing Golden Surfer style file with DX and DY instead of CELL SIZE since the input pixels are non-square. Use the FORCE CELL SIZE ...
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52 views

Displaying RGB raster on QGIS with no enhancement with Python Console?

I'm working with a RGB raster on QGIS 2.6.1, on a Windows 7 machine. I need to set the Contrast Enhancement option to No Enhancement with the Python Console (not through the Layer Properties ...
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87 views

How to calculate the distance to the nearest water source?

I have a polygon hydro layer of my study area and am trying to calculate the distance to nearest water bodies from my site. Since my site are 2km*2km grids I am not sure how to calculate it? Whether ...
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55 views

Problem with importing GeoTif files in QGIS

I have installed the new version of QGIS (2.12) and the newest OSX version (El Capitan). When I tried to open GeoTif files with QGIS, it always crashed! Then I tried an older version of QGIS (2.8) and ...
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35 views

Using OR and ISNULL in Raster Calculator

I am using ModelBuilder for ArcGIS Desktop 10.2 I have the following code in the Raster Calcualtor which works in some cases but not in others. Int(Con(IsNull("%A%")|"%A%"== 0,"%B%",float(%Max%) + ...
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42 views

Raster to ascii tool converting all data to one value (ArcMap) [on hold]

I am having an issue when converting a raster to ascii. With extract by mask I have selected the area I am interested in and subsequently resampled the data from 5km to 2 by 2 m (required for use in ...
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19 views

USGS Raster Conversion with GDAL Returns Blank .TIF File

I am new to GIS systems. I installed GDAL to convert .ADF files to .TIF files to obtain image heightmaps. It outputs a GeoTIFF .TFW file that I can't open, and a .TIF file that is blank (all white). ...
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30 views

Preserving Reclassified Values as Attributes?

What is the BEST way to preserve original raster values as attributes in the output raster when reclassifying? I see that this question has been asked before as Making reclassified raster layers ...
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Attribute table not changing when using Mosaic on rasters

I'm looking to "merge" 2 rasters together. One is the original base land cover raster with 6 classifications/land use classes. The other is a raster from converted polygons that are essentially ...
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Can't set transparency to a RBG raster on QGIS

I need to display an RGB raster on QGIS, with Multiband Color render type. After I set the Contrast Enhancement option to No enhancement, this is how the image is displayed. No issues so far, since ...
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2answers
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Changing height/interpolation/shape of raster layer

I am kind of a beignner in ArcGIS and thought about and googled this problem for two days now. I am working in ArcScene making a 3D visualization of a bedrock surface of a town. I have a polygon ...
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1answer
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Creating point shapefile from GeoTIFF using GDAL/OGR?

I have a 0.05 deg global maps (~8000 files) in GeoTiff format. It's a kind of a mask containig "1" and "0". I need to create a point shapefile for each raster with points located over "1" values of ...
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need to clip multiple USGS quadrangles in Geotiff format to statewide index in polygon format

I need to trim the collars off of many USGS 7.5 minute quadrangles for a state. I have the quads as GeoTiffs and have the polygon boundary for the whole state. I think there are about 1446 ...
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33 views

Raster copy multiple rasters keeping name but dropping extension

I have ~100 rasters I need to clip to an area. All rasters are saved as .bil files, and for use in later processing I was trying to make these have 'no extension for esri grid', but keep the same ...
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Raster data QGIS and SpatiaLite?

I am a german student and study Geoinformatik. I have the task to store Raster data in SQLite. So use the turotial from the gaia page to Create a database and store a image (TIFF) named NaturalEarth. ...
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I clip a raster with a vector mask in qgis, the result is correct but its a little bit of, why is this?

On one side the result is "bleeding" over the vector on the other side its more than one raster pixel from the vector on the inside. How to correct this? http://i.imgur.com/d0v6mqt.png ...
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Display PostGIS raster as GeoTIFF layer in QGIS [duplicate]

I want to display a raster loaded into a PostGIS (2.2) enabled PostGRES database (9.3) as a GeoTIFF layer in QGIS. I get the sense that this needs to be done by creating a view in PostGRES and then ...
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45 views

QGIS slope percent calculation

I'm using QGIS and I'm trying to calculate slope < 20% from a file I have but when I use the raster calculation SLOPE < 20 the result is all black. What am I doing wrong? The data is already in ...
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32 views

How to test if a point shapefile is in a raster in ArcMap using Python?

I have a shapefile where the features are points. It should be about 500 points. All of this points are on top 5 different rasters. Some points are in one raster, but some others are not. I need to ...
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2answers
144 views

R raster predict using lm() time series

I try to make a prediction in raster using linear regression based on past rasters but I can not capture the lm() model in order to feed it to predict(). # # calculate regression in a raster stack ...
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1answer
25 views

Performing spatial join on two rasters using ArcGIS for Desktop?

Have search on this question but cant quite find the solution i seeking. I have two rasters, one with nodata cells the other is complete. I am seeking to combine the two rasters. Where there is a ...
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Spatial Join Points Vector with Raster Dataset using Arcmap

I have a points file of taxi drop off locations and a raster file grid. I am trying to get a count of each point on a raster cell. How do I go about doing that? It is like I am doing a spatial ...
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PostGIS Raster performances

I ingested two Landsat images into PostGIS database using : raster2pgsql -I -C -s 28356 -M -t 100x100 LS7_20150425_B40.tif public.red | psql -d postgres -U postgres raster2pgsql -I -C -s 28356 -M -t ...
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Best way to store, elaborate and query raster data [closed]

I have created multiple raster images with GRASS-GIS (~150Gb), that I'll need to multiply for a certain coefficient, and query the results that need to by saved just temporally. The portions of the ...
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32 views

Strange display of raster in ArcMap

I have a Raster file jp2, in the full zoom there is a strange black dots on the border of the raster, but keep zooming these dots disperses see images
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55 views

What is faster - a matrix, raster or a dataframe?

I have rasters over which I am performing mathematical operations. For example, where I need to calculate flow distance or distance between two grid points. What format is generally considered faster ...
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Adding .tif files with various bit depths to a raster mosaic

So I have a few georeferenced .tif files that I need to add to a raster mosaic, however the problem is that some of these are 8 bit unsigned TIFFs while others are 1 bit unsigned. After adding all ...
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Using raster2pgsql to display data in QGIS

I am quite new to this process (using raster data in PostGIS) and tried to find some tips/solutions on other threads but I didn't manage to get things working. I ingested some Landsat data into my ...