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

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Remove Frame Border from USGS scanned images in ArcGIS

I have a couple of USGS scanned maps like I want to remove the frame border from these images so that I can use them in ArcGIS. Is there algorithm or python script that I can run to remove the ...
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13 views

Second order rectification display problems

I'm using GRASS 7.0 to geo-rectify oblique images taken from a fixed altitude and using RTK-GPS data as a GCP (as a vector file) for the process. The survey area is very small and flat, so I'm not ...
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20 views

How to best import a US Map Schematic?

I would like to use the following wiki US Map schematic as a background to my map work. (http://en.wikipedia.org/wiki/File:Blank_US_Map.svg) It is a .svg file, and GeoReferencer is unable to import ...
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48 views

Point to raster: QGIS vs ArcMap

I have an equidistant point grid (0.5m) and created a raster from it in QGIS and ArcMap, with different results: QGIS: Raster -> Conversion -> Rasterize Result: raster, with points in the top left ...
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44 views

moving window regression on raster stack in R

I want to perform a moving window regression on every pixel of two raster stacks representing Band3 and Band4 of Landsat data. The result should be two additional stacks, one representing the ...
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54 views

Align vector and raster layers with D3

I have a geocoded raster image that I want to use as the background to a vector map with D3.js. The screenshot shows the layers in QGIS (grey is raster). Here's the markup for the map: <div ...
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32 views

How to create a map series of different rasters (same location, same legend)?

We have hundreds of raster images at the same location (same dimensions, pixel size, projection, etc.). We would like to display each one in its own map using the same legend with the same vector ...
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27 views

Extracting area from DEM Raster?

After applying constraints to the DEM I polygonised the raster (using GRASS r.to.vect.area) The result is shown below with a lot of vector with resolution = [30 * 30] Is there any solution to make ...
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51 views

Convert polygon to raster and give value to null cells

Is there a way to convert polygon features to raster while also populating null cells with a specific value? As in, can I create a raster from a polygon shapefile and have the tool populate all null ...
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35 views

Combining information from one raster with another raster

I have two rasters, A and A1. Raster A is the image below that is greenish and has the following attribute table: The table has two fields that I need: Value and class_name Raster A1 is the ...
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32 views

Modifying DEM elevation data in QGIS using a polygon

I've tried searching through the existing questions but am struggling to find a succinct answer to what I am trying to achieve. For background, I am running a flood model in TUFLOW to help support a ...
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29 views

In ArcSDE, SQL Studio Manager 2012, How to get pixel data using a point layer?

I was using 'where' and 'ST_Intersects' with polygon data to get values 'under' my point layer. Example: Select rd.[FORESTNAME] as Forest, Count(Distinct morel.[OBJECTID]) AS Observations From ...
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33 views

How to check if a file is a valid raster image?

How to check if a file is a valid raster image? Valid in the sense of not being corrupt, the file record is complete. The GIS corollary to "zip --test somefile.zip" to test if an archive's integrity ...
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34 views

Landsat Data to Map Slums in India

I am working on a project to answer the following geographic question: How much have slum areas increased in Mumbai, India, since the 1970's (or earliest data). I have downloaded LandSat imagery and ...
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62 views

How to avoid “Unable to compute a transformation between pixel/line”?

I am trying to re-project from Equi-rectangular to the NASA global EASE grid (Equal Area Scalable Earth) grid 1383 586 with a ~25 km cylindrical projection (ESPG=3410). The file is provided as HDF5. ...
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28 views

Where to find QGIS geoprocessing results?

Is there a way to access in QGIS 2.6.1 something like the Geoprocessing Results window found in ArcGIS? The History and Log window in QGIS appears to show the geoprocessing results from SAGA, OTB ...
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22 views

QGIS - r.* commands not found

I'm very new to GIS and have recently installed QGIS on my mac desktop computer, running Yosemite 10.10. I'm working with DEM data for stream network extraction, but the majority of grass raster ...
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66 views

How to OCR topographic maps

I have old topographic maps that i have scanned and converted into pdf in Actobat XI 11. I need this pdf to be text-searchable (not mere image). To do this i tried text recognition in acrobat but it ...
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53 views

Python Script to iterate numerous, single-band rasters for arcpy.CompositeBands

I have a large collection of single-band geotiffs (NIR, Green, and Red) that I would like to composite using a Python script. The goal is to iterate through multiple folders in a main directory, ...
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51 views

QGIS - quickly style categorical map

Example situation: a raster map that denotes various provinces in a country, each indicated with a unique value. Goal/question: quickly (for 'preview' purposes, not making a publishable map) assign ...
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21 views

Calculating Autocorrelation in Different Zones

I'm an intermediate-ish user of ArcGIS 10.2 (win7 pro, hardware robust enough to handle very large datasets and computationally intensive analysis) with perhaps a simple problem that's evading me ...
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38 views

How legitimate is smoothing raster data that has been converted from polygons?

I am interested in applying this methodology to census block data after conversion from a raster: http://rutgerscps.weebly.com/uploads/2/7/3/7/27370595/censusdatasmoothing_brief.pdf Basically, the ...
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61 views

GRASS GIS r.walk issue

I have been playing around with GRASS GIS to do a simple cost analysis of getting from point A to point B. I have a DEM clipped to the study area, a raster containing the friction costs, as well as ...
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62 views

Add Surface Information alternatives in QGIS?

Is anyone aware of a single tool or possible routine of tools in QGIS (2.6) which emulate the results of the ESRI 3D Analyst tool 'Add Surface Information'? I have several polygon shapefiles (some ...
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34 views

Extract by mask/copy raster a RGBA (4bands) raster results in a greyscale image in photoshop discarding all RGB composite info

I used a polygon Shapefile to extract by mask (ArcGIS) the sea area from a RGBA (4 bands aerophoto) raster. The Extract by Mask caused up-sampling from 16 bit (my raster's initial pixel depth) to 32 ...
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102 views

Performing Maximum Likelihood Classification in R

I'm trying to perform maximum likelihood classification of landsat imagery using R, I have been searching for a package that implements it but so far I haven't found it. What is the easiest way to ...
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55 views

Calculate surface map from PostGIS

We need to create surface maps from the website. The data is stored on PostGIS (2.1) as a table of Point geometries with a field indicating a thematic value. The optimal solution would be to produce ...
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52 views

ArcGIS Split Raster tool results in black rasters

I have a rather large raster that I am trying to split into small tiles in PNG format to upload to Autodesk Infrastructure. I came across the Split Raster tool and thought it would do exactly what I ...
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36 views

Problem with QGIS raster interpolation from a point shapefile after duplicating the shapefile

Let me explain a problem I had with QGIS to see if somebody else has experience it. I created a raster from a point shapefile through the Raster-> Interpolation menu with no problems. After that, I ...
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53 views

Does interpolation create a vector or raster?

I have been reading about interpolation and am trying to understand whether interpolation results in a vector or raster. Say I have a layer of points and I am interested in creating a raster that fits ...
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64 views

OpenLayers/Geoserver - can I create a tiled, zoomable raster layer?

Still a relative newbie with Geoserver and OpenLayers. Developing an application with Geoserver in the back, OpenLayers (3.0) in the front. I have a requirement to display imagery on top of a base ...
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80 views

Add Rasters to a new GDB/Mosaic Dataset in ArcGIS ModelBuilder

I'm attempting to add rasters to a new mosaic dataset in a new file geodatabase, all in the same model. However, the Add Rasters To Mosaic Dataset tool does not recognize the NewMosaicDataset or the ...
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24 views

How do you symbolise a 32-bit raster in ArcObjects?

For rasters that are ABOVE 16-bit - you cannot apply a colormap - so what is happening when you symbolise in ArcMap a 32 bit raster, it's certainly possible. I'm trying to emulate this funcitonality ...
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29 views

Worldfile incorrect? Puzzler: all resources supplied!

Trying to manually create a worldfile for gif images of surface currents supplied by the navy here. I have QGIS and am decent at using it but the world file tool is failing without error on me (even ...
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61 views

Metric maps vs topological maps for path finding and UI rendering of indoor floor layouts

I'm building a software to map indoor floor plans of large facilities (like malls). I read through some of the questions on this forum, but my constraints are a little different than the ones ...
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62 views

SAGA GIS - raster image from Civil 3D

I am a new user of SAGA GIS software. I need to interface the Civil 3D 2015 and Hec Ras software in order to create a flooding map. In order to put in communication the two softwares, I have to use ...
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53 views

Generating ESRI compatible raster reference files in QGIS?

Backstory: employer is GIS incapable and most of the data we work with doesnt play nice with GIS software. That said, we have a client who is very GIS oriented. My boss (not my work) is providing them ...
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63 views

creating composite raster tiles from multiple vector layers as new background map in QGIS

I have been patiently restyling OS Vectormap product to create a map background I'm happy with, which i want to now use as a background for a leaflet map using QGIS2leaf. I understand that performace ...
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30 views

Saving fields after a raster join with python arcgis

I am working on a raster processing script in which i join a categorical raster with a table that includes some extra data on each category. After much hassle, I have the join working, but I can't ...
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53 views

Assigning score to raster based on cell overlap with other raster and field value

I have a set of rasters that I've assigned scores to individually (scored based predominantly on values of other fields). The scoring scale is the same for all rasters, but the factors that determine ...
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65 views

Transparency on black/white raster after clipping in QGIS?

I'm new to this forum and QGIS. I'ld really appreciate it if you could help me with my problem, since I couldn't find any solution online but people experiencing the same issue. It seems as if this ...
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30 views

Slope tool output has artifacts

So I've tried using the slope tool for a DEM using an appropriate Z-factor and the output is smooth, but it seems to be over-estimating slope angle. I would prefer to reproject the DEM (to NAD 83 UTM ...
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Reprojecting a population raster from LAEA to lonlat

I have a population density raster from the EEA which is based on the CORINE land cover 2000 data. ...
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TIFFDirectory.getAsMetadata() is not including GeoTIFFTagSet. Any solution to this problem? — JAI

The source code appears to simply copy the TagSet List object to the IFD and then the TIFFMetadata. I don't understand where it is losing the tagset as it is in the list before the call. Anyone ...
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57 views

Using the accCost() function in R: questions regarding the transition layer

I am trying to use the accCost() function from the gdistance package in R. I load my cost raster using the raster()function from the raster package. According to the documentation, I need first to ...
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47 views

How to change values in a raster file at particular positions?

I have a collection of coordinates which comes from a QGSGeometry object. The shape is a polygon. example: qgsGeometry [[(75.2172,17.6566), (75.8499,17.9613), (75.5218,17.2113), (75.2172,17.4574), ...
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QGIS Mac OSX version cannot batch write output files after rasterization

Happy new year everyone, I have been trying to batch rasterize a series of .shp files using QGIS for Mac OS X, and keep coming up against a strange problem. I am using the QGIS 2.6.1 user interface, ...
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119 views

How to extract percentage of land cover from a raster according to multiple shapefiles?

I have a raster map that represents land cover of a region, and different shapefiles (total 120) in the same region. I want to know the percentage of every land cover for each shapefile. For example, ...
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61 views

Tiff Raster File slow to Load in Win 7 64 Bit QGIS 2.6.1

I have been unable to load a Geo Referenced Tiff file in 2.6.1, I have found it it will load but takes minutes, It will load quickly in 2.4 It is a Lidar file so it is large, about 14 gb in size, I ...
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How can I equalize raster?

I've got 2 rasters , its seems that 1 has the data equalized (all values from 1-65535 are there) and the 2nd don't . Is there a process I can run in order to equalize the data in the 2nd raster ? ...