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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2 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
24 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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13 views

How to apply pixel swapping algorithm on fuzzy member values? [on hold]

I performed fuzzyCmeans on an image and land-coverfractions(fuzzymembervalue) are generated Now I want to apply PSA..but am stuck on how to proceed, do I have to start with making a finer resolution ...
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0answers
13 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
53 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
29 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
6 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
33 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, ...
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1answer
43 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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36 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
20 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
25 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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29 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
29 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' ...
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1answer
49 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
10 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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20 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 ...
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0answers
22 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 ...
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1answer
105 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 ...
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0answers
86 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
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2answers
219 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 ...
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0answers
42 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 ...
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1answer
60 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 ...
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1answer
81 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 ...
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0answers
65 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
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1answer
132 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 ...
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0answers
19 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
40 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 ...
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0answers
13 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 ...
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0answers
28 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 ...
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1answer
80 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 ...
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2answers
87 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 ...
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2answers
101 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
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2answers
63 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
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1answer
91 views

QGIS Semi-automatic classification plugin install error on OS X 10.10: matplotlib.backends.backend_qt4agg

I have tried repeatedly to install the QGIS Semi-automatic classification plugin via both (1) Plugins > Install & Manage Plugins and (2) manually based on other comments I found here, but I ...
2
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1answer
87 views

Change detection between two classifications in QGIS?

I have two raster classifications. They have the same number of classes which use the same ID (each class has a unique ID). I would like to get information on the changes between classes i.e., class 2 ...
3
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0answers
69 views

Classification of 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 ...
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0answers
36 views

How can i perform area calculations in a raster file?

I would like to know if is possible and how can i calculate all areas or parts of it in one raster? Can i do it using the raster calculator? All help is appreciated, Best regards
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0answers
49 views

ENVI: Postclassification, remove pixels of certain size

I did a classification over multiple Landsat imagery in ENVI 5.1, which turned out not too bad (ice and snow in Cyan in the picture below). Now I am about to do a postclassification to filter out ...
0
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1answer
25 views

How to prevent symbology reclassification from adding 0s to the Range?

How do I prevent symbology's "Natural Breaks" from automatically changing my range to include multiple 0s after my decimals? Example: Range was originally 1 - 249. I switched to Natural Breaks and the ...
9
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2answers
272 views

Methodology for Hansen classification of Global Forest Watch?

I have just discovered amazing Hansen´s classification about forest loss and re-growth, available at http://www.globalforestwatch.org/, published in Science, 2013 as: Hansen, M. C., Potapov, P. V, ...
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1answer
63 views

How to get a total amount of cells per classification type in a raster in ArcGIS 10.1?

I did an supervised classification for for this watershed. The attribute table doesn't have the count for total number of cell for each classification. I've created a field titled 'Count' with type ...
2
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2answers
119 views

Classification to attribute

Using Esri Desktop Advanced 10.2.2 is it possible to create an attribute based on a classification method, i.e. Jenks? To elaborate - if you use the symbology tab in a layers properties, you can set ...
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1answer
41 views

Why does the undefined “ghost classes” arise during supervised classification in ERDAS IMAGINE?

After a supervised classification in ERDAS IMAGINE I have some undefined "ghost classes" in the attribute table. Also have a look at this youtube video at about 7:12. I'm wondering why they arise and ...
3
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0answers
48 views

Appropriate resolution of images for image classification?

I am attempting to perform image classification on some maps that I have in PNG format. This classification is failing due to there being too many many pixels in the training samples (I appear to be ...
2
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1answer
53 views

QGIS Print Composer - Display Symbols for Empty Classes?

I am working on a map of mortality rates for several racial/ethnic groups and I have created custom classes to encompass the rates instead of the QGIS classes created through its various modes. This ...
4
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1answer
177 views

Identify shadow on Landsat image by Hillshade Tool (spatial analysis) in ArcGIS?

I would like to automaticaly identify shadows on Landsat scene in mountaineus area using Hillshade Tool (ArcGIS 10.1). I have 1 Landsat image from one date DEM (SRTM) from the same area To create ...
6
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3answers
337 views

How to easily identify/classify coniferous forest from one date Landsat image?

I am pretty new in remote sensing and I am trying to identify/classify coniferous forest cover from single date Landsat scene. According to my preliminary web research I have these possibilities: ...
4
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4answers
450 views

Extracting tree crown areas from remote sensing data (visual images and LiDAR)

I am looking for a method to process a remote sensing image and extract the crown areas of the individual trees from the image. I have both visual wavelength areal imagery, and lidar data from the ...