The process of sorting or arranging entities into groups or categories; on a map, the process of representing members of a group by the same symbol, usually defined in a legend.

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3
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0answers
12 views

Classify image using segmentation analysis using QGIS and OrfeoToolbox

My first question on stackexchange (sorry for my english language)! I use stackexchange often to understand GIS principles and workflows. I wasn't able to find a answer. For this project we made a RGB ...
1
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0answers
19 views

Working with Mobile LiDAR (extracting walls)

I am currently working on mobile point clouds in order to extract 3D building models in the residential area. I could successfully classified ground, vegetation and building roof lines, but still have ...
4
votes
0answers
23 views

How can I get a numerical (or value) display for equal intervals in a layer?

I'm looking to classify regions on a map by the amount of light pollution in the area. I have the varied intensities (0 through 60) plotted using a color map, but is there anyway that instead of a ...
3
votes
0answers
26 views

How to classify difference surfaces having almost similar Reflectance responses?

I am using ENVI 5.3 to classify a Region of Interest clipped from Landsat 8 OLI. I have already performed calibration of my DNs by transforming it into Radiance and derived Reflectance image using ...
2
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0answers
47 views

Classification and measurement of feature basing on scan [closed]

It`s not entirely a GIS question, however maybe somebody can help. I need to automatically classify and then measure area of certain elements on image. That image is a scan of a thin wood slice and ...
4
votes
2answers
114 views

Double classification for symbols in QGIS

I am using QGIS version 2.14.1 (Essen). I have symbols that I have classified according to certain value from one of the columns in my shapefile. Furthermore, I was wondering if it is possible to do ...
1
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0answers
12 views

Spectral classification for crops

I'd like to do a classification using a multispectral raster (1 Blue 475, 2 Green 560, 3 Red 668, 4 Red Edge 717, 5 Near IR 840). I'd like to classify the crops (kiwi plants). I tried a few ...
2
votes
0answers
18 views

SAGA 2.2.5 Problem Object Based Image Segmentation

Every time I use the Object Based Image Segmentation with Landsat 8 data I get a segmentated image which looks like a spider's web. The image contains no 0 values. Anyone has a idea how to fix this?
2
votes
2answers
36 views

Using SCP image classification to find swimming pools?

i'm currently trying to use the scp image classification plugin to find swimming pools in an aerial image. It is just an RGB image as if it had infra red this'd be a lot easier. Does anyone know how ...
3
votes
2answers
49 views

Classifying raw LAS data as bare earth in ArcGIS for Desktop?

I have a raw LAS data that has only one return (no second/ third.. return) and not classified yet. The only information I have is intensity and elevation. Is there any way that I can classify bare ...
0
votes
1answer
53 views

Remote sensing accuracy assessment - McNemar`s Test

I would like to know how you determine the f12, f21 parameters for use in the McNemar`s test when for example I have two confusion matrices such as below: (where f12 = number of cells misclassified ...
0
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0answers
7 views

Data type doesn't match error in Sieve filter

I classified some land cover types in aerial image with Erdas Imagine, now I want to remove classification errors showing very small areas. I tried to use Sieve filter, but getting error notification ...
1
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1answer
51 views

Extracting above ground features from unclassified LAS [closed]

What's the best way to vectorize features from LAS? I have "Classified" LAS files, however they were never processed for classification. Thus of 181 million points (9 tile sample) about 60% are class ...
4
votes
4answers
112 views

QGIS classifying vector data

I am trying to classify a shapefile based on rule set, following this tutorial. This is the result: What I want to ask is: 1. How to insert the classification result (water, land etc) into the ...
0
votes
0answers
35 views

How to export training area information?

I did a supervised classification of a whole Landsat 8 image with 700 Rois (training areas) with the Semi Automatic Classification Plugin. I want to export the class names, the coordinates and the ...
1
vote
3answers
178 views

Classifying individual trees from labelled LiDAR point cloud [duplicate]

I have a classified point cloud for an area of 250*250 square meter, with 1 meter resolution. It has a 5 lakhs points with an average point density of 9 (means around 9 points within a pixel). I ...
1
vote
1answer
29 views

Image Classification on Photos From Camera?

A little bit of background: So I have some photos of 1X1 meter plots that were taken with a NIR digital camera. They have been georeferenced, corrected, etc.. I am interested in performing an image ...
5
votes
1answer
153 views

Orfeo Toolbox object based classification in QGIS tutorial/workflow

I have a set aerial photos of vegetation which need to be classified. Instead of using manual interpretation, I want to try using Object-Based classification based on the Orfeo Toolbox in QGIS ...
0
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0answers
27 views

Retrieving raster classes as data type in Python Script tool?

I want to program a python script tool in ArcGIS where the user should be enabled to input a classified raster and, based on this raster, the classes should be selectable. EDIT: As is suggested in ...
5
votes
2answers
139 views

Can LiDAR differentiate between rock and soil?

Can LIDAR by itself, tell the difference between rock (large and small) and soil? I'm under the assumption that the answer is no. However, I wanted to check here with the experts as I was told by ...
3
votes
0answers
36 views

How to use a conditional logic on Impervious Mapping

I am trying to use a logic ( rule -based classification ) to extract built-up area, similar to as suggested by Xu (2007).He uses, three spectral indices, SAVI( Soil Adjusted Vegetation Index), NDBI ( ...
2
votes
1answer
18 views

Symbology classification scheme for Solar PV Electricity Generation

I am presenting some data relating to rooftops suitable for solar PV and their potential PV electricity generation. I am mapping the above data for the study area. What would be the best symbology ...
0
votes
0answers
48 views

Maximum Likelihood Classification in ENVI

I am a new ENVI user and I am trying to perform a supervised classification of a Landsat 8 image with the maximum likelihood algorithm. In order to run the classification, I have to insert a Scale ...
1
vote
1answer
37 views

How to define a threshold in Principal Component Image for Urban mapping?

I am working on an Urban mapping and i would like to know how i could define a threshold value for extracting built-up areas from a PC (Principal Component) Image ? I am interesting on how to ...
3
votes
2answers
56 views

How to give polygons a classificaton code in ArcGIS?

Does anyone have a trick for assigning polygons a code based on the classification classes? For example, if I symbolize the population of census blocks with 10 classes using Natural Breaks, I would ...
1
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0answers
49 views

Needed help to launch SVM classification in eCognition

I would like if somebody help me to launch SVM classification in eCognition. Have you met any tutorials? I was searching through ecognition community, but there I find only basic KNN supervised ...
5
votes
1answer
73 views

Aggregating polygons with space between them

Im currently editing a large dataset that has large chunks removed throughout (buffered road network). The areas adjacent from each side have coinciding attributes, but have this large erased area in ...
2
votes
2answers
58 views

Adding more than one legend in QGIS Print Composer?

I'm using QGIS 2.8.4 and I can't seem to figure out adding more than one legend to my Print Composer. Say I want a larger map and then an inset map -- showing perhaps a different classification/color ...
1
vote
0answers
21 views

Band Separation from regular cameras

I have removed the IR block filter from a Sony digital compact camera so it has become multispectral (in a way). In addition to that I placed a IR pass filter, so it only captures photos in the ...
0
votes
1answer
18 views

Rule of thumb for selecting ROIs for supervised classification

I'd like to perform a supervised classification using the Semi-Automatic Classification Plugin and a maximum likelihood classification algorithm. I read about a rule of thumb which says "if training ...
1
vote
0answers
25 views

Normalizing raster data: getting a range of output values as opposed to a Boolean output [duplicate]

I converted a polygon shapefile which defined ED boundaries to raster. The value i based the raster surface on was a population count for each ED. The values ranged from 568 and 18160, as expected, ...
0
votes
0answers
36 views

Adding Masked Classes to unsupervised classification in ERDAS Imagine

Prior to supervised classification of a landsat 8 scene in ERDAS Imagine I masked two classes using the 'Mask' tool [Raster - Geometry - Subset & Chip - Mask] I now wish to add these two classes ...
0
votes
1answer
26 views

Call Toolbox operators of ENVI from IDL code

Is it possible to call the clustering/classification algorithms included in the toolbox of ENVI (gui) from IDL (source code) and how?
0
votes
0answers
38 views

Finding spectral reflectance bands for classes created from unsupervised classification

I am working on a project that requires separating water and non-water features based on unsupervised classification in ERDAS Imagine 2015. I have taken the original image, and assigned it into 50 ...
1
vote
1answer
128 views

Creating building footprints from LAS files

I wish to create building footprints from the classification in our LAS files. I have filtered out the building points, using the point cloud filter. But I now trying to join the outermost points of ...
4
votes
1answer
274 views

Random Forest land cover classification in ArcMap?

I am an undergraduate student working with a very large data set (to me), and who has NO experience with R, but is fairly comfortable with ArcMap. I have about 60GB of 8band 1m satellite imagery of ...
1
vote
0answers
27 views

Using same ROI/Signature for classifying spatially different rasters?

Using QGIS SCP Plugin, I have classified a raster of a state. Can I use the same ROI/signatures to classify rasters of other states?
3
votes
0answers
89 views

ArcGIS quantile classification

I have been implementing a workflow previously devised ArcGIS 10.2 in R. The process involves a discretization of an integer raster (the cells are counts) through quantile reclassification. I've ...
2
votes
0answers
48 views

Create a raster dataset containing the number of returns from a las file? [duplicate]

I already created DEMs, DTMs, DSMs from a LiDAR (LAS) file with a little help from the internet. However, right now I'm kind of stuck in my research. I want to create a raster file which contains ...
0
votes
0answers
168 views

Object-based classification using R and Orfeo Toolbox

I am trying to run an object-based classification using R. The Landsat images were segmented using Monteverdi (Orfeo Toolbox) and training samples (segments) were selected. My problem is that the ...
0
votes
0answers
33 views

Finding Land Cover colormap (*.clr) for IGBP Land Cover Classification?

Where can i find a land cover classification colormap (*.clr) for IGBP land cover classes? How can i apply the legend colors on the land cover classes? I'm using ArcGIS.
0
votes
2answers
87 views

Area calculation of mapped categories in ArcGIS 10.1 Basic

I have performed supervised classification (Interactive supervised classification and Maximum Likelihood Classification) on landsat reflectance raster data to classify it into seven land use ...
1
vote
1answer
75 views

Can ArcGIS automatically round labels for a raster symbolised according to a classification? [duplicate]

I'm looking for a way to automatically adjust the reported precision of the label field for a float raster rendered in ArcGIS according to a classified symbology. Currently, the a classified raster ...
2
votes
1answer
67 views

Styling line layer based on two attributes in QGIS ? (1 discrete and 1 continuous)

I have found a really helpful tutorial to style points based on two attributes. Is it possible to make style lines based on two attributes? I have a shapefile with streets that have two attributes: ...
1
vote
0answers
33 views

qgis Semi automatic classification pluggin how to add text to rows in attribute table

I want to use a previously created shapefile as Training shapefile in the semi automatic cassification pluggin. Therefore i added 4 fields to this shapefile: Macro_ID (int), MCl_info (text), Class_ID ...
0
votes
1answer
47 views

Is there an Export All Features in View Extent equivalent with ArcPy?

I would like to dynamically classify a layer's symbology based on the current view extent. As in, quantities of a specified field will be classified into quantiles based on the range of values of the ...
1
vote
2answers
29 views

QGIS: Class boundaries

I have seen that people already had issues about overlapping class boundaries with the classification of graduated vector data. I am wondering if there is somewhere written in the documentation if ...
2
votes
1answer
211 views

supervised classification

I am having a problem in creating new signatures in Signature Editor in ERDAS 2014. Whenever I click on the icon (i.e., after selecting the aoi), it shows an error which says "unable to open ...
3
votes
1answer
433 views

SAR - Using the Intensity or the Amplitude for the classification

In a Sentinel-1 Level 1 Ground Range Detected SAR data product, Intensity = Amplitude * Amplitude. Should the intensity image or the amplitude image be used for radiometric calibration when using ...
2
votes
1answer
73 views

NDVI in ENVI: Output format issue

I am working on NDVI in ENVI... the output file is in Envi Standard format... I required it in Envi Classification format, which can be done through Envi Edit Header tool... This requirement is for ...