Questions tagged [classification]

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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Classifying LiDAR ground points using laspy?

I have a classified LiDAR point cloud (.las) with misclassifications. The walls of steep surfaces that should be ground (class 2) have been misclassified as vegetation (classes 3, 4, 5). I am ...
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semi automatic plugin v value in automatic threshold calculation

what does the 'v' defined value stands for in automatic threshold calculation in semi automatic plugin in QGIS
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1answer
167 views

single feature probability in ERDAS object-oriented classification

I'm using ERDAS for my UAV image classification (consists 6 land cover types) and I performed the first step of Object-oriented classification, Single Feature Probability (SFP). It outputted a ...
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1answer
72 views

Problem with supervised classification (using GRASS) [duplicate]

So I was playing with supervised classification with GRASS. The first issue that I ran into was right after the first two steps of classification (v.to.rast and i.gensig) which was: unable to read ...
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NumPy ValueError: operands could not be broadcast together with shapes (1,2) > (1678,2218)

My objective is to classify a Landsat 8 image using supervised classification. I have a training point shapefile data and a preprocessed Imagery. I want to use Random Forest classification method. ...
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2answers
182 views

Orfeo Toolbox KMeans Classification failure

I am trying to process a Landsat8 OLI image using the Orfeo Toolbox Unsupervised KMeans Classification application. I obtain the following error message: Error when loading model ...
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59 views

Identifying clusters in classified imagery data

I am relatively new to working with satellite imagery at 1 m resolution and am struggling with a methodology for "grouping" the imagery. Using ArcGIS, I have performed an ISO classification on some ...
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2answers
386 views

How to change border style for classified data?

I would like to classify my layer according to two categories (for example year and type of land) and would like to show these classifications with a different colour of the border (for 'year') and ...
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1answer
44 views

Classifying GPS locations according to Land area classification using ArcPy?

I have a vector layer for the GPS locations and a raster for the landuse/landcover. I've realized a supervised classification to classify the categories in the Lulc and a maximum likelihood ...
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1answer
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How to tell if a geo-point is on a road

I am looking for a robust way to determine if a geo point (long, lat) is located on a road I am currently using openstreetmap overpass-api with the following query: way[highway](around:3.0, {lat}, {...
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58 views

Using result raster of Semi-automatic classification to obtain spatial statistics?

I finished classification (use SACP in QGIS), and got a classificated raster. Now I want to obtain characteristics such as sum area of class, areas of different polygons separately, etc. I tried use ...
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891 views

Classifier with SVM algorithm for sentinel 1A image

I am classifying rice for the Red River Delta with 2 class: class 0: Rice class 1: Not rice I used svm classifier algorithm. However, after running the code, the classifier operated for a long time ...
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1answer
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Duplicate Layers in eCognition

I am attempting to use eCognition Developer to segment and classify 5-band UAS imagery. When I go to create a new project in eCog and input my imagery (individually selecting the five .tif files), it ...
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Training Sample Automation

Background, in case it helps: My objective is to (eventually) fully automate the mass digitization of grain silos. To this end, I have set out to first find a way to automatically identify silos in a ...
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Performing Object Based Image Analysis with NAIP?

I use NAIP imagery (primarily in QGIS/GRASS) for agricultural analysis. I want to separate out objects such as grain silos, farms, buildings, &c. using segmentation and classification. Is this ...
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992 views

Identifying training sites?

Prior to image classification, collection of training sites and obtaining a signature file is the most critical step. Field visits with a reliable GPS Unit is usually the first step followed by ...
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1answer
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How do I export training samples from IDRISI?

I have been tying to implement this paper on an SVM classifier wherein I need to extract training samples from an image and run an SVM classifier on it. The paper says the following: IDRISI Andes ...
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QGIS: Cropland Data Layer - how to add class names to .tif file?

I'm working with a clip of the Cropland Data Layer (raster), which has a number for each value coded to a crop type. I want to add these crop type / class names to the .tif file (and have them show up ...
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831 views

Image Segmentation and Object-based Classification in Google Earth Engine [closed]

I have tested three methods to segment my image collection: (https://code.earthengine.google.com/699f04706c114260068275acd2605644) var l8sr = ee.ImageCollection('LANDSAT/LC08/C01/T1_SR'); function ...
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Photogrammetric point cloud classification

My question is regarding the point cloud classification and editing work for a photogrammetric point cloud generated using drone based imagery. My objective is the generation of a digital elevation ...
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151 views

Using Maximum Likelihood Classification and raster border in ArcGIS Desktop?

I have tried multiple times to see if this was an issue with my supervised classification, but I don't think it is. I created my training samples and created a signature file. Per my course, I need to ...
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1answer
102 views

Classify area by year

I'm trying to classify a set of buildings (grey) in a layer, according to construction year, in a number of different areas (orange). In Orange – areas with a sum of buildings inside. The ...
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1answer
292 views

GEE: apply ee.Reducer.mean to a list

After classification of an image in GEE, I got 2 lists of user's and producer's accuracies (1*7 and 7*1 dimensions). How can I calculate an average value for each of them now? print('Validation ...
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Pixel-based and object-based classification!

I would like to understand if pixel-based classification algorithm (e.g. Maximum Likelihood classification ) can be used for object-based classification (i.e. after a segmentation procedure). On the ...
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1answer
330 views

QGIS 2.18.19 and OTB 6.4.0 Application

I've tried the whole weekend to get the Orfeo Tool Box running in QGIS 2.18.19 (stand-alone version) and today I finally managed it by setting the paths to the bin-folder of the stand-alone version on ...
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1answer
366 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?
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How to Make automatic classes with algorithm in qgis modeler?

I have 1 column of numeric data in one attribute table of a layer made of points. I want to regroup this data in classes (style) with the Qgis modeler and each class must have a specific lenght that ...
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1answer
428 views

Taking classification image from ENVI and using it in ArcMap?

Loading ENVI file into ArcGIS Desktop? is a question similar to this but used a slightly different way of going about things so it made it not fit my situation so here's my situation. I ran an ...
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1answer
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ISOdata classifier in QGIS?

Is there a function that produces an ISODATA unsupervised classification in QGIS? The only unsupervised classification function I can find is a KMeans.
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How to assess significant land cover changes using Chi-square test?

I have a series of land use maps at different times as a result of a classification process on Landsat images. I am mapping 3 different thematic classes : bare soils, vegetation and croplands. I ...
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593 views

Remote sensing Classification and texture analysis compared with QGIS zonal statistics

I am Using Geomatica to analyse suburban spectral signature in Las Vegas. Ran a texture analysis on all band images. Combined texture bands with original image bands to run an unsupervised ISODATA ...
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3answers
250 views

Landsat 8 striping/banding citation

Does anyone have or know a citation for the Landsat 8 striping that affects some scenes (Brazil shown here). It's apparent in all bands (B3 here at 100% stretch) and is present in both RAW and ...
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1answer
286 views

Creating new field with values from different fields QGIS [duplicate]

I have combined different layers (vector) in a merged layer. All layers had one specific land-use type, so now the new layer has fields called 'tree', 'paved', 'building', 'water' and 'plants'. All ...
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1answer
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Question about storage space (multispectral imagery vs. classified GIS rasters) [closed]

I have a quick question about storage space in ArcGIS. When I have limited storage space, I am trying to figure out which one on average takes up more space: multispectral images or classified GIS ...
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1answer
689 views

QGIS - Orfeo Toolbox: how to run support vector machine classification?

I am trying to classify SPOT images with the support vector machine classification in Orfeo Toolbox with QGIS. I installed Orfeo Toolbox with OSGeo4W. I have made a ROI image with 600 training samples ...
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1answer
344 views

Can anybody help me to know the type of land covers in DIVA GIS data?

I have dowloaded the country mask land cover data from DIVA GIS website. I don't see the name of different types of land covers.
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2answers
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Interpolating LiDAR scattered ground data?

I wonder if someone can give me a hint on how to interpolate sparse data. I have a 1km by 1km tile located in a dense rain forest area. Original LiDAR data are 37,395,021 points. I have played with ...
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2answers
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Stratified random sampling with Google Earth Engine Error

I am trying to sample points from a classified raster using Google Earth Engine, but am running into some problems. I developed a script based on the Classification video located here. Here is a toy ...
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1answer
397 views

QGIS saga supervised classification [closed]

I'm using QGIS 3.0 with the expanded SAGA options. I created a training file in SAGA standalone that I am using, but would prefer the GRASS kappa comparasion options. I have already performed the ...
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1answer
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Implementing a classification on Google Earth Engine

I am attempting to implement a classification based from a decision tree (attached as image below) where there are 5 classes. These classes are based off the different water reflectance values in ...
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2answers
659 views

Erdas Imagine Error: Performance warning: Covariance calculation requires stack processing but input layer stack isn't suitable. How to solve it?

I am collecting signatures right now and when I am adding them to the Signature Editor Erdas says: Performance warning: Covariance calculation requires stack processing but input layer stack isn'...
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1answer
652 views

Thematic layer in ecognition

I want to assign class by thematic layer in ecognition. I have digitized road edges and I want to classify the roads in my 'road class' using the shapefile (polyline) of my roads. How do I do this?
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1answer
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How does MERIS collect vegetation height data?

In GlobCover 2005 and 2009 project, the sensor used for spectral data collection was MEdium Resolution Imaging Spectrometer (MERIS). It observes the Earth in 15 spectral bands in visible and near ...
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1answer
153 views

ArcGIS Desktop Classification Histogram

Is there a way to access the classification histogram which is used when classifying data in ArcGIS desktop? The background is I have a series of data layers for which I need to use the same ...
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0answers
150 views

Supervised classification using endmember spectra (using ENVI 5.1)

We are trying to map land cover classes over a small watershed. We have selected training sites (during a field campaign in early 2017) and determined their spectral profiles on a Landsat 8 image ...
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1answer
6k views

Using Orfeo Toolbox object based classification in QGIS tutorial/workflow?

I have a set of aerial photos of vegetation which needs to be classified. Instead of using manual interpretation, I want to try using Object-Based classification based on the Orfeo Toolbox in QGIS ...
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1answer
693 views

Doing supervised classification for images on ERDAS?

i want to do a supervised classification for images on ERDAS, using GIS, i clipped the areas i want to use as training/signature from the original images. but i just can't create a signature file, ...
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373 views

R: Can raster predict function pass to predict.rfsrc (a prediction function in a parallel verion of RandomForest)?

It seems that raster predict function can pass to predict.randomForest by setting the "type='response'". I am using a parallel version of randomForest package called the "randomForestSRC" and I am ...
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0answers
248 views

Importing classification bitmap made by another software into QGIS?

I am currently trying to import a classification bitmap made by our own deep learning software into QGIS. The classification is saved in a TIF file, the classes are 8-bit integers. We have the class ...
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1answer
124 views

How to classify vegetation in 500x500 m polygons in a very coarse way in QGIS

For a simple species distribution map for the Dutch Wadden island of Terschelling, I want to give each 500x500 m polygon (reference grid = EPSG 28992) a specific color that coarsly corresponds with ...