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.

learn more… | top users | synonyms

-3
votes
0answers
27 views

4 sequential Landsat image cant be merged into one single file, in QGIS. how to solve this issue?

i am trying to create land-use, land cover classification by QGIS. i have Landsat images downloaded from earth explorer. these are *.tiff files. but my region is not covered by single pic. thats why, ...
3
votes
2answers
190 views

How to compare a classified raster dataset to another polygon dataset?

I am going to perform an unsupervised classification on my dataset and will get a map as a result. The objective is to rebuild an already existing map (of different soil types) with my new dataset. ...
1
vote
2answers
30 views

Do integer values in a Confidence Raster correspond with a specific probability %?

I have been using the Maximum Likelihood Tool (Spatial Analyst extension, ArcMap 10.3.1) to classify a number of rasters into "Vegetation" and "Bare Ground" classes. I'd like to have some sort of ...
3
votes
2answers
72 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
vote
0answers
37 views

Classifying data as Natural Breaks using ArcPy?

Is there any chance I can create a simple python script to classify my data as Natural Breaks? I have only created a script for quantile classification, but it is not enough for my work. arrp = ...
0
votes
1answer
817 views

ENVI 5.2.1 How to do an Accuracy Assessment using test data from a shapefile

ENVI 5.2.1. From a .tiff image (4 bands) I created a Supervised Classification Maximum Likelihood .dat file. Now I want to perform an Accuracy Assessment using test data from a shapefile. I've tried ...
1
vote
2answers
248 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 ...
1
vote
0answers
21 views

Crop/ forest/grass classification in Erdas

I am trying to calculate crop land, forest and grass land to check the irrigation potential during the period from Landsat 8 image using supervised classification in ERDAS. I am finding difficult to ...
0
votes
3answers
125 views

Assigning class codes for LAS files? [duplicate]

I have LAS files with code 0 - never classified. I have no other classes other than this. How do I assign class codes for my LAS file?
3
votes
1answer
319 views

Classifying above ground LiDAR points in ArcMap?

I recently used the LAS Dataset toolbar to classify a .lasd file. The process classified the majority of points as unassigned with the rest being ground points. The study area has many tall buildings ...
0
votes
0answers
24 views

QGIS image classification to use maximum likelihood, minimum distance or spectral angle algorithm?

This should be a straight forward one... I have selected over 100 ROIs from ground truthed data. I am using LANDSAT 8 imagery. I want to now perform the classification (which I guess is a supervised ...
2
votes
1answer
314 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 ...
2
votes
1answer
326 views

Unsupervised raster classification using GDAL

Is there an equivalent in GDAL to the Arcpy ISO data unsupervised classification tool, or a series of methods using GDAL/python that can accomplish this?
1
vote
0answers
16 views

Maximum likelihood classification- changing class colour with every layer

I created a signature file, where I defined 4 different classes, which I named and coloured specifically. When I try to use the maximum likelihood classification tool for other layers, the classes ...
0
votes
0answers
21 views

how to do classification when the spatial analysis toolbox is not available?

I am required to do classification on a polygon feature class based on the rage data. However, I have realised that our ArcGIS lisense does not have "Spatial Analysis" toolbox as active, therefore I ...
-1
votes
2answers
68 views

Applying SLD file exported from QGIS in GeoServer - why is color not applied?

I was trying to put style of color classification that was created in QGIS. It works in Geoserver but the colors are not shown. It is always single color. I have read that this is often a problem with ...
0
votes
0answers
19 views

Summarize function in whole data using ArcGIS ModelBuilder?

I have to do special analysis on a geomarketing data. In the stage I am in right now, there are different polygons (distance buffer from one central shop from others) which have some points inside (...
2
votes
0answers
152 views

QGIS - Semi-Automatic Classification Plugin v.4.9.5 - When trying to create ROI getting Error[43]: Attribute table error

when I try to create a ROI within the Plugin: Semi-Automatic Classification Plugin, I am getting the Error: Attribute table error. Which means it is not creating MC ID / MC Info or C ID / C Info in ...
0
votes
0answers
7 views

Masking a sat. image pre-classification? ArcMap/ENVI

I need to classify the tree crowns in a .5m satellite image. To remove unwanted features in the classification (water, roads, buildings), I want to mask the image with an NDVI file first. I have the ...
0
votes
0answers
18 views

Post Classification NDVI using ArcGIS

Does anyone have any advice about doing a change detection from two NDVI rasters that have already been classified into 10 classes? values 1 - 10 are classified, values 11 - 255 set null. I've used ...
8
votes
1answer
367 views

Using 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 ...
1
vote
0answers
27 views

Classification of multiple values at the same point

If I have a point dataset with multiple values for the same geographic location (e.g. residuals from a regression where multiple individuals live at the same location) which I classify using quantile ...
1
vote
1answer
29 views

Landsat 8 composite image using different resolutions?

I have created a composite image of Landsat 8 using bands 2 to 7 (blue, green, red, NIR and SWIR) using ArcGIS 10.1. For bands 2-4, I've pansharpened them to 15m spatial resolutions using the ...
3
votes
1answer
60 views

Random Forest out of the bag and confusion matrix

I have implemented Random Forest classifier to classify remote sensing data in R. The original code comes from here: How to perform Random Forest land classification? Everything works fine, but what ...
0
votes
0answers
41 views

Multi-class classification in Google Earth Engine

I am wondering if it is possible to do multi-class classification with Google Earth Engine. And if so how? I am currently able to do binary classification as in the following code, based on the ...
2
votes
1answer
83 views

QGIS: How to exclude outliers from the legend classfication using an expression

I am trying to make an equal interval legend using a rate of burglaries per 1000 habitants using a combination of a column with the counts of burglaries and a column of total population using census ...
1
vote
1answer
37 views

TrainImagesClassifier (SVM) fails when executed from within QGIS modeler

I made a small model in QGIS that runs Second Order Image Statistics, the SVM Trainer, and Image Classification, all tools from the Orfeo provider. The problem is it fails everytime. When I run the ...
0
votes
1answer
33 views

How to perform radiometric correction and enhancement processing to get the coastal habitats?

I have a satellite image that is processed to unsupervised classification. I have to get the coastal habitats from this image. The satellite image before classification process need radiometric ...
0
votes
0answers
17 views

Assigning classes to resterized segments in QGIS

I am new to using QGIS. I made a mean shift segmentation and rasterized the vector segments. I need to classify the segments. How can I go about this?
1
vote
0answers
75 views

Classifying building walls from LiDAR point cloud [closed]

I am currently working on mobile point clouds in order to extract 3D building models in the residential area. I could successfully classify ground, vegetation and building roof lines, but still have ...
-2
votes
1answer
55 views

How to interpret accuracy assessment results for classified data?

eCognition has the ability to perform an accuracy assessment for classified data by using an error matrix based on a TTA mask. The image shows the results of the accuracy assessment. Is there a ...
0
votes
1answer
102 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 ...
1
vote
0answers
21 views

exclude value from feature analysis classification (ArcGIS extension)

I am using feature analysis to classify small (mm) round features from the landscape. I have calculated the circularity of each shape and I want to exclude those which are not round enough. Does ...
0
votes
1answer
35 views

Methodology for Image Classification (beginner) [closed]

I'm a beginner with remote sensing and have the task of creating a land use/land cover map of a region in India from IRS imagery. I've never performed an image classification before, although I do ...
3
votes
2answers
103 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 ...
2
votes
2answers
51 views

Is it Possible to Resize the Pixels

I classified this image in ArcGIS 10.3, but my Professor said the pixels are big and I should make it smaller. This is my problem: is there any tool that can use to make the picture grains finer. Or ...
1
vote
1answer
42 views

Maximum Liklihood Image Classification; Does this algorithm consider RGB Band values only?

if it is correct that Maximum Liklihood classification algorithm takes into account RGB values of the bands only, then is it useless to stack other bandslike NIR SWIR etc prior to go ahead and use ...
2
votes
0answers
30 views

Stripes and Distortion in classification result when performing maximum likelihood classification in ArcMap [on hold]

I have trouble performing a supervised classification in ArcMap 10.3. I created training areas and executed the "interactive supervised classification"-tool, which works totally fine and gives back ...
1
vote
0answers
15 views

how do I get percentages of classes in a classified image?

I am using ArcMap 10.3 I have two layers, one classified raster, Landsat based dNBR, where classes show burn severity, and a shapefile containing polygons, drawn based on the dNBR image and that ...
3
votes
0answers
110 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 ...
4
votes
0answers
27 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
53 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
votes
0answers
64 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
135 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
vote
0answers
25 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
42 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
61 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 ...
1
vote
1answer
77 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 ...
0
votes
1answer
24 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 ...
0
votes
0answers
11 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 "...