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
55 views

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

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
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4answers
79 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 ...
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0answers
21 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
30 views

Object based classification using segmentaiton - QGis and Orfeo toolbox

I would like to apply an object oriented classification of Land Use and Land cover changes based on image segmentation of a Landsat 8. I am using Linux Mint 17.1 (64bit) and QGis2.8.1 and Orfeo ...
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0answers
28 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
15 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 ...
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0answers
15 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
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1answer
45 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
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2answers
87 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
63 views

Mean Shift Segmentation Error: The following layers were not correctly generated - QGIs + Orfeo Toobox

I have been trying to do an object based classification using QGis + Orfeo Toolbox. I downloaded the Q Gis 2.8.2 and OTB from OSGeo4W Network Installer. I am using OS Windows 7 enterprise. When I ...
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0answers
35 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 ...
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1answer
62 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 ...
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0answers
42 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
13 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
21 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 ...
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1answer
86 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 ...
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1answer
57 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
44 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 ...
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0answers
29 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
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2answers
78 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 ...
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1answer
42 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 ...
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0answers
10 views

Georeferencing of ROI in ENVI?

I had an image which is not georeferenced for my study area. I have processed the data and made roi files in envi 4.7. Now I have georeferenced the image data. I have a doubt that whether the roi ...
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1answer
55 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
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1answer
59 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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46 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 ...
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1answer
30 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 ...
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0answers
34 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 ...
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0answers
43 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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0answers
30 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
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1answer
78 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 ...
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0answers
11 views

Creating a class based on city limits from GIS

I need to classify an entire city as one class. I have the GIS shapefile of the city limits, but am not sure how to delineate the entire area as one class based merely on the limits.
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0answers
27 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
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1answer
45 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
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1answer
150 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
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0answers
118 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
246 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
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0answers
65 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
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1answer
72 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
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1answer
95 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 ...
0
votes
1answer
98 views

Creating histogram/statistics/scatterplot by classification tool in ArcMap?

I'm currently working on a land cover classification with Landsat 8 imagery. I already subjected the imagery to pre-processing (atmospheric and topographic correction) and I mosaiced two images. Now I ...
4
votes
1answer
206 views

Unsupervised classification in QGIS

I was trying to learn unsupervised classification in QGIS 2.6 following the tutorial video: https://www.youtube.com/watch?v=mI80eENtWSE When trying myself, clicked Run during the process it shows the ...
0
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0answers
21 views

lulc unsupervised classification in envi for modis 250m data

I've got modis 250m data with NDVI,RED,BLUE,NIR,MIR bands....i have to obtain 10 classes such as Urban,Evergreen,decidious,cropland,fallowland,plantaion,water,barrenland,land with scrub,land without ...
1
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1answer
45 views

Graduated values in symbology based on specific attribute in QGIS

I'm trying to solve the problem I've raised up in here.. I've rearranged the attribute table that looks like this: Important to notice is that the field "gruppo" is composed by 2 unique ...
0
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0answers
15 views

lulc mapping from modis surface reflectance

can i prepare LULC with 10 classes from MODIS surface reflectance level 3 data 500m resolution... if so what are the preprocessing techniques should i do on the data..i have to prepare LULC for yearly ...
0
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0answers
35 views

Lots of unclassified objects in eCognitions basic classification

Not for the first time I came upon the following problem in eCognition: After segmenting the objects, selecting samples for several classes and calculating their "membership function" in several ...
1
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1answer
108 views

unsupervised random forest classification in R

I want to compute an unsupervised random forest classification out of a raster stack in R. The raster stack represents the same extent in different spectral bands and as a result I want to obtain an ...
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0answers
19 views

How to make break values which are outside of the value range? [duplicate]

I want to compare mean temperatures for three future periods (2011-2040, 2041-2070, 2071-2100) with the measures mean temperatures of 1971-2000. My resulting shapefiles will show the difference ...
1
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2answers
133 views

Las dataset to raster, ground points only

I'm trying to make a raster from a las dataset. I want to only use points classified as ground points but I can't figure out how to do this. What I've tried is: Create las dataset from 2 .las files ...
2
votes
2answers
147 views

Counting plants in aerial images using unsupervised classification?

I am relatively new to GIS and I have the following problem: I want to extract the number of plants per row in a crop land. I have and RGB mosaic from aerial images. I think that I could do an ...
3
votes
2answers
74 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. ...