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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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
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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
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1answer
223 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
441 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 ...
2
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2answers
236 views

When is it best to use a Proportional Symbol Map or a Graduated Symbol Map?

I am having trouble understanding the difference between the two, or why it matters. How do these two differ from each other?
2
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1answer
42 views

Panchromatic Image Classification GRASS GIS

How to perform an unsupervised classification of a single panchromatic satellite imagery in GRASS GIS? I tried it many times but I keep being prompted for a second image or other images in the ...
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0answers
61 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 ...
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0answers
30 views

NetCDF Qgis problem

I have a problem with importing a NetCDF file in Qgis. I added the file as a raster layer and I can see the layer. Now I want to change the colours by using the classify function in the properties ...
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0answers
30 views

Image and AOI files have different Map Info Error Message in ERDAS

I have a raster image at 15m resolution and trying to conduct subpixel classification in ERDAS. I extracted two AOI's (area of interests) from the image and used it for my signature derivation. But ...
0
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1answer
57 views

How to classify shapefile values in QGIS?

I would like to classify shapefile values using graduated style in QGIS, but instead of using the default mode of classification (e.g.natural breaks with values range 0-10, 10-20, 20-30), I would like ...
2
votes
0answers
128 views

Graduated symbols not appearing for all polygons

I'm using ArcGIS 10.2.2. Trying to map some city populations using graduated symbols. Should be simple, but while most of the polygons are being assigned symbols, some aren't. For example, in the ...
3
votes
1answer
187 views

Looking for example of a Random Forest tutorial to estimate spatial distribution

Could anyone point me to a Random Forest tutorial for predicting a spatial random variable? Or an easy dataset to try to work through. For Decision Trees and Random Forests, I found some very good ...
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0answers
57 views

Importing representations from a Layer File

I'm trying to incorporate representations as part of my data model. I have set up representation rule for my feature class, which is part of a feature dataset. The way I have the data categorized is ...
0
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1answer
64 views

How do I classify my counties to color the bottom / top 25% in area?

I have a map of my state with county boundaries. What settings should I use to color the counties based on their area but only if its area falls in the bottom or top 25% of county area? For example, ...
1
vote
1answer
161 views

Does anyone know a way to do a supervised classification on a google maps image to show only hedgerows? [closed]

I would like to then use the hedgerows by bringing it into QGIS as a layer. I need to know what software to use and the method to make such a layer? I would like to use a google earth image in Grass ...
2
votes
4answers
205 views

Export ground returns (.las) from classified point cloud

I have lidar data that is classified as several categories (water, ground etc.). I need to open this lidar data in some software (it will be great if it would be a open source software) and delete a ...
2
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0answers
50 views

What does “Information [18]: Select at least one signature” in the semi automatic classification plugin mean?

I am using the semi automatic classification plug in to classify vegetation and water in a satellite image. I create training shp and signature list. When i hit "classification preview" it gives me ...
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0answers
57 views

how to calculate distance in sub pixel mapping from Atkinson's paper?

Condition from atkindon's paper http://info.asprs.org/publications/pers/2005journal/july/2005_july_839-846.pdf for every sub-pixel the attractiveness Ai of a pixel i is predicted as a ...
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0answers
62 views

Unsupervised (ISODATA) classification in ENVI returns fewest classes possible

Running an unsupervised (ISODATA) classification in ENVI 5.2 consistently returns the fewest classes possible. For example, set to produce anything between 50 and 70 classes, the classification ...
2
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0answers
102 views

Remote sensing Classification and texture analysis compared with QGIS zonal statistics

Some back round: 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 ...
2
votes
1answer
135 views

Can I use TIFF files for zonal statistics in QGIS or ARCGIS?

I am completing a remote sensing paper and am doing most of the work in PCI Geomatica, where I have 2 separate files. One from running a texture analysis algorithm containing 6 band layers from a ...
2
votes
2answers
298 views

land Use land cover classification

I am working on Land Use/Land Cover Classification of the Hindon river(India) watershed extracted using Aster DEM. Landsat 8 scenes had been used and mosaicked for the required AOI using the Watershed ...
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0answers
146 views

How to create ROI in Semi-Automatic Classification plugin QGIS

while trying to classify landsat images, I get the following problem: I click on the pixel I want to define a ROI, but the ROI polygon that the plugin creates appears in a different part of the image ...
0
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1answer
88 views

Compare Multiple attributes visually

I am working on a project in which I want to take point features( tweets) and compare them to the GDP per capita of countries. I would like to have my end result be such as the following: GDP Class ...
0
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0answers
45 views

Image formats to use for land cover classification in Python? [duplicate]

I am supposed to classify images for different land covers or land uses in Python. I read somewhere that the spectral module of Python is required to do the processing of Hyperspectral image data. ...
1
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0answers
19 views

Does fixed classes exist in QGIS?

I'd like to create several images of voronois polygons in QGIS; each images having differents values joined to the voronois. I tried to load a qml style with the values I want to keep (8 classes : ...
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0answers
32 views

Create lake bottom substrate class surface from classified points?

I have been getting acoustic sounding data (http://www.biosonicsinc.com/index.asp) and creating bathymetry for several years now, but I am also tasked with creating a substrate surface. I orginally ...
3
votes
1answer
172 views

How do you classify unclassified pixels in a land cover geotiff tile?

While printing out the raw pixel values of a GEOTIFF land cover tile I found 90 % of pixels have normal values i.e. those that the documentation describes (8 bit integers describing a land cover ...
0
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1answer
615 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 ...
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2answers
130 views

Classifying DEM using Height Differences in ArcGIS ModelBuilder?

I would like to classify DEM into some classes, into a shp file with equal intervals of 200m (0-200m, 200-400m, 400-600m... 3400-3600m, higher than 3600m), by using Model Builder in ArcGIS 10.2. For ...
0
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0answers
54 views

sub pixel classification

I have a doubt regarding the output of sub pixel classification. After we apply sub pixel and get end membership of every pixel, does it mean that a class having the highest membership of the pixel is ...
4
votes
2answers
161 views

Random Forest to estimate land use in past with Landsat

I am new in Machine Learning and in R. I am working in my Master thesis. I am trying to estimate the LULC of the years 1984, 1990, 2000, 2011, 2014 for characterizing the forest dynamics. I have for ...
1
vote
1answer
87 views

Looping inside r.mapcalc in GRASS GIS

I have a Land Cover classification map that I created from 2m resolution multispectral imagery and I am trying to downsample the results to a 20m resolution class map. The climate in question is ...
1
vote
1answer
140 views

error of randomforest classification with Landsat data

I want perform randomforest classification on Landsat data. Here is some code I found from a paper. But when I run into the "classification" part, there is an error said "Error in eval(expr, ...
0
votes
1answer
118 views

How to show percentiles in Qgis?

I have a polygon layer with several fields, like: population, wage, age, etc. I would like to show the percentile value for those fields. How can I do that in an automatic way with QGIS 2.6.1?
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0answers
69 views

Classifying beach/mudflat area of Landsat Images

For my work I need to capture the total catchment area of a beach using mostly Google Earth images. I attached an example with this post. So the whole catchment area comprises the sandy beach as well ...
2
votes
1answer
67 views

How to convert an endmember collection spectral signature file from OLI sensor to TM and ETM+ sensors

I'm working on some supervised classifications using scenes from the landsat legacy archive wich include ETM+, TM 5 and OLI data from 2001 to 2014. I have training and validation points for each scene ...
0
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0answers
54 views

Subpixel classification to extract forest roads hidden under canopy from Satellite data

I have a rapid eye image of 5m resolution. My task is to extract road from a densely forested area with canopy cover at some sections of the road. I have applied threshold segmentation and also region ...
1
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0answers
80 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 ...
0
votes
0answers
32 views

QGIS vector data, graduated symbology (choropleth), discrete class bound values [duplicate]

This doesn't seem to bother anyone else, so maybe it's just me. I'm using QGIS to create a choropleth map of historic property boundaries. Since settlement occurred in pulses, I'd like to use Jenks' ...
1
vote
1answer
154 views

How do I read and modify heat map value classification on QGIS?

I am trying to create a heat map on human encroachment using the heatmap plugin of QGIS 2.2. I have no problems creating a good looking raster file using a 2 km radius but I can't find my way around ...
1
vote
0answers
59 views

How do I use Multispec for Landsat data?

It seems that I only can use the Clustering if I want to cluster only one band data.. If I open up more than 1 band (in one image), the cluster toolbar is disabled? optional: Is there any free ...
0
votes
1answer
62 views

When parametric classifiers fail?

In which situations are statistical assumptions (e.g. multivariate normal distribution within spectral classes) for parametric classifiers (e.g. maximum likelihood ) not valid for land-cover ...
1
vote
1answer
327 views

Interpolation and classification of soil texture data

I am trying to interpolate soil texture data on a research area. I know how to interpolate the data by making three layers for clay, sand, and silt. What I want to know is if there is anyway to ...
1
vote
0answers
289 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 ...
6
votes
2answers
314 views

What is the theory behind graduated symbols in QGIS?

QGIS offers 5 methods of classifying vector map data (quantiles, equal interval, etc). What is the theoretical base of these methods? If there are certain methods suitable for certain types of data or ...
1
vote
1answer
207 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
1answer
134 views

Setting lower and upper limits to classes in kriging interpolation, ArcGIS

I am using the kriging interpolation tool. I included two dummy values within my dataset:- an upper limit and a lower limit. I ran the tool in arc map 10.1 software. However, I want to change the ...
0
votes
1answer
154 views

Removing salt and pepper effect

In a land cover raster (categorical map) that is a product of classified satellite image, what is the best way to remove "salt and pepper" effect from the image after classification. I am not ...