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

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112 views

DEM error when trying to do topographic correction in GRASS

I'm new to GRASS gis and I'm trying to do a topographic correction (i.topo.corr) of 9 ASTER bands using SRTM dem. I keep getting this error message: ERROR: Illumination model is of CELL type Is ...
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634 views

Stretched raster symbology not working in ArcGIS for Desktop?

I have some DEM rasters (from the same data source so I think they're uniform in all file specifications) that I'm symbolizing using the same stretched color ramp. I set the stretch type to min-max, ...
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486 views

How to calculate area of respective pixel?

I wants to create NDVI Map, In which it shows an area of respected pixel value lies in map.I have NDVI value within -0.6 to 0.7. Suppose,I wants to calculate area of 0.5 NDVI value with scale of map....
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2k views

Combining two overlapping rasters (combine cells, retain both values) using ArcGIS for Desktop?

Using ArcGIS 10.2, I am trying to combine two rasters which are identically overlapping in shape and extent, but with different values and counts. As an end result I would like each cell to retain ...
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124 views

Different ST_AZIMUTH results for ST_PROJECT points along the same original bearing

I'm trying to develop some way of determining line of sight (LOS) between two geographical points about 1km apart or less using ST_3DINTERSECTS or something similar. BASIC PROBLEM: Along the way, I'...
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318 views

how to calculate area verses each NDVI value?

I created an NDVI map, I want to calculate area of vegetation verses the respective NDVI value of the given map. Which tools are used for this process and what steps are required?
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44 views

How to show number of patches in a neighbourhood?

Given one raster file containing only one zone that indicates patches of vegetation in a city and a shape file containing neighbourhoods for the city, explain how you could create a map that shows the ...
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77 views

Placing a cost raster in Arcmap Table of Contents in 10.2.2

We have a set of routines that have been used for writing rasters to the ArcMap table of contents from our tools. The code that always worked is this: /// <summary> /// Used for ...
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181 views

Finding coordinates of the image corner

I have a .bmp image with a map. For creating image i used a Ingeo 4.4 and function MakeImage() What i know: Height an Width of bmp image dpi Map Scale Image Center's coordinates in meters. What i ...
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196 views

Java how to create geotiff from points

I have an array of objects where each object has three fields: lat, lon, and category. It is essentially pixels that have been given a land use category. I cannot figure out how to turn this data into ...
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2answers
58 views

QGIS: how to identify a visible raster layer among large view (composition of rasters)?

I have QGIS project loaded with many raster files. For a given area, (ex: under my mouse pointer), I am looking for way to identify which (raster)layer provides the visible data. To start, I will ...
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381 views

rasters as independent variables in logistic regression: must they have the same values classification?

I am planning to build a predictive model for land productivity using arcGIS 10.1. and logistic regression. In my model, the Independent Variables would be, among others, distance from rivers, ...
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798 views

How do I convert a .bil (and associated .clr, .blw, .hdr, and .stx) files into georeferenced rasters in R? OR to geotiffs using gdal_translate?

The title says it all. I've got a bunch of .bil files, which I can open in R using the raster command pointed to the path to the .bil file. But I don't know how to efficiently incorporate the ...
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170 views

How to change the symbology on many image files within a group?

I have a group of raster images from lidar data (so a DEM). When loaded in, they all have different symbology - so their color scheme and color ramp are all different. I would like to create a group ...
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751 views

Selecting raster data by location: for raster and feature class data

I have rasters covering certain spots in my environment, I'm looking for a way to extract the values which occur at locations which are defined by a selection of feature layers. I've tried with the ...
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1answer
79 views

What is a better idea for modelling a fault plane than as TIN? [duplicate]

I am working on a project which runs on ArcGIS platform using VB.NET. It is to model a sub-surface fault plane (currently a plane rectangular model with some dip) and then to find required distances ...
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801 views

Is there a way to write single bands raster from multi-band layer faster in r?

I have 1000 multi-layer rasters and have to export each separate layer to a tif. Some friends recommended R to do the job. I used the following code: library(raster) namesVector<- c("layer1", "...
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429 views

Import raster into PostGIS using Python

I am trying to import information from a Bathymetric Attributed Grid (BAG) file into PostGIS using Python and psycopg2. I'm working, for now, on a Windows box with pre-compiled packages, so I don't ...
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58 views

How do I remove TIR bands from current stacked ASTER

How do I remove TIR from already stacked ASTR that has VIS and SWIR bands. I want to do it in ENVI 5.0. Is there a workaround to do this ? The bands I stacked has VIS, SWIR, and TIR.
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364 views

How can I create an animation with raster data in qgis?

I have 4 raster images showing different coniditions of air flow distribution at different times. I'd like to create an animation to show the change from image 1 to image 4. How can I do this? I tried ...
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81 views

Show raster data in WEB

I have downloaded Landsat8 image and use matlab to processing temperature and vegetation. Then I insert data into PostGIS. I used QGIS to display the results but i want show in web. How to display the ...
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85 views

How to export a IDW raster while keeping the search radius data

I want to export my IDW rasters that I made in ArcGIS to QGIS, however when I export my raster, the values are there but are no longer displayed. They are stored within each cell and are not ...
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814 views

I'm converting a raster to TIN and a large section of it didn't convert properly (ArcGIS 10)

I've got a DEM for a pretty large area and I need to create a TIN. I'm using 3D Analyst Tools > Conversion > Raster to TIN. The process runs without any error messages, but a large section of the TIN ...
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569 views

How to set the output extents of rasterization in QGIS

I am trying to rasterize a bunch of vector based shape files in QGIS. All these files are covering certain types of ground use in a city (houses, street, open field,...). I need these files to be ...
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952 views

QGIS DEM (Terrain models) Mode Slope creates wrong data [duplicate]

I have a DEM raster file downloaded from the USGS site. The file can be downloaded here. I am trying to create a slope raster in percent with the DEM tool in QGIS. The GDAL command is the following: ...
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275 views

How to use the raster calculator in the processing modeler of QGIS

I am trying to create a easy way to do raster analysis by building a model for two way raster calculations. I have two raster layers that I want to combine into a single raster. For now I've done this ...
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80 views

How to deal with empty corners in raster when calculating fragmentation index

I have clipped buffer area around coordinate from one big raster (forest cover). Such created raster was loaded in R where PatchStat function (library SDMTools) gives fragmentation index. After ...
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218 views

Raster Attribute Table Where Each Pixel = 1 Row

In ArcGIS, is it possible to create a raster with an associated attribute table where each pixel is represented by a "row" in that table. I would like to specify unique attributes for each raster ...
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259 views

How to combine Boolean and Fuzzy logic?

So I have a set of 5 Fuzzy Memberships and a polygon feature class, to which I already added a yes/no field. For the final map, I need to combine/overlay all Fuzzy Memberships and the rasterized ...
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123 views

GEOTIFF Binary File with Color Display Issues

I have a GEOTIFF in QGIS that shows values of 0 and 1 and I want the 0 values to have no fill so that background vector layers can show through and so I can easily overlay things in a print composer ...
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122 views

QGIS combine Vectorlayer and Rasterlayer to one shapefile

I have to create some Thematic Maps, especially Choropleth Maps on Matlab. Therefore i've found a shapefile which I can use, but need to draw some lines there. I've imported my shapefile as a Vector ...
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344 views

How to perform a standard deviation stretch on a raster in QGIS

Is there a way to perform a (2) standard deviations stretch on a raster image in QGIS 2.2? I have found the raster styles menu, but the help says there is no help in my language (English) and whilst ...
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618 views

QGIS Quickly switching overlapping raster images

I'm new to QGIS, and haven't used arcGIS in about 5 years, however I've just seen someone using arcGIS and was able to quickly switch between overlapping rasters when checking registration. The top ...
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732 views

Floating point calculations in QGIS

How do I manage floating point calculations in QGIS? I have carried out 3 consecutive calculations on landsat bands. I end up with 32 bit floating point rasters on which I can't carry out a 4th ...
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78 views

What format to store/use four band Raster data

I have four band aerial photography - RGBI. I need to share it with my users, a mixture of MapInfo, QGIS, and ArcGIS. What format should I store/serve the data in? GeoTIFF isn't well suited to four ...
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1answer
1k views

Converting a raster to a polygon

I need to convert a raster into a polygon, and I ran into "Error 000863: Invalid GP Data Type" After searching, I saw this solution online. Basically I needed to convert the float raster to an ...
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94 views

QGIS Grid Division/Grid Product etc. results are wrong projection

I have several raster grids, all 4320 columns, 2160 rows in WGS 84 projection. They are loaded from ESRI ascii files. When I use the Processing Toolbox to carry out arithmetical transformations on the ...
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2answers
2k views

How can i convert a raster from continuous to discrete?

I have a tiff that is 'invalid' for a lot of tools and will not let me view the attribute table. I think this is because it is "continuous" rather than "discrete". Does anybody know how to convert it ...
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97 views

How can i combine the colours of one raster with values from another

I have two Tiffs with data from the same area. One is in colour and when I use the identify shows a 'color index' number (eg. 141), then Color(a,r,g,b)(eg. 255,90,255,0). The other tiff contains a ...
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147 views

How to build and pass remap for floating point raster without getting Reclassify ERROR 010255?

I am receiving the following message when executing my python script: ERROR 010255: String remap must be used with a string field. My input raster is floating point and I would like to ...
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336 views

How to cut multiple neighboring raster images

I'm looking for a way to cut a larger number of neighboring aerial raster images (each sized 1x1 km, resolution 10 cm per pxel) into four smaller raster images (size 500 x 500 m). I haven't done this ...
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2answers
2k views

How to clip an Openlayers OSM Background to a Vector Boundary?

I'm new to QGIS. In my project i have two layers: one is my vector (city boundaries) and the other is the OSM (obtained with the plugin). How can I cut the OSM along the edges of the vector? I want to ...
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2answers
932 views

TIFF/Raster to Point shapefile question

Apologies in advance if this question is incredibly basic, but I've been googling around and I just don't know where to start. I've downloaded some nighttime luminosity data from NASA, and the data ...
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2answers
501 views

How to identify valleys on DEM in ArcGIS 10.1 [closed]

First, What is the best and easiest way to identify valleys in a DEM raster? Second, how do you create a least-cost pathway for each valley in a region based on low angle slope and proximity to ...
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162 views

How to get Name of IRaster object using ArcObjects?

I have an IRaster object as output from a function. I need to be able to get the name of that raster. Is there a way that I can do that? I know that I can't mask an IRaster as an IRasterDataset. If I ...
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178 views

How to calculate the sum of all cells in a raster layer upstream of a specific point?

I have a rainfall map which covers large area. However, I'm interested in the total value of rainfall over a specific subcatchment. If I don't have the shapefile which defines the boundary of this ...
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517 views

If I convert a TIN to a raster in ArcGIS will results from the two versions of the surface be comparable?

I have converted a TIN to a raster. I found that the top of a bund wall shifts laterally in position between the TIN and the raster into which it has been converted using the TIN to raster tool in ...
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1k views

Use of Raster Calculator in ModelBuilder

I have the following equation: 3000*(1-exp((-0.000664)*input raster)) I want to make a tool to use this equation on raster images. I want to do this with the Raster Calculator with the help of ...
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184 views

gdal_rasterize using a “string” as src_datasource

I would like to use a string as src_datasource for gdal_rasterize program. Is it possible to use something like a WKT definition to translate a single point to a raster? Somethink like ...
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700 views

ArcMap Raster to NetCDF - lat/long

I need to convert a few files which are projected in WGS84 into netCDF. NetCDF requires lat/long. I am a bit confused on how the process is handled by ArcMap especially after looking at the online ...