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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6
votes
2answers
207 views

Handling mountain shadows when classifying Landsat 8

I'm trying to classify some area in northern Mongolia using Landsat 8 satellite images from 2013. Since the recordings were made in winter, the sun is very low at the acquisition time. Therefore there ...
0
votes
1answer
252 views

Masking clouds with Fmask

I have been trying to mask clouds with the quality control band with landsat 8 imagery. The problem I continue to run into is that the quality control bands mistake tops of buildings and concrete as ...
1
vote
1answer
78 views

Signature File Creating Issues [closed]

I'm working on a school project and running into an unexpected issue while trying to create a signature file. I have four classes in the Training Sample Manager consisting of: Permeable, Impervious, ...
0
votes
0answers
11 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
48 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
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 ...
2
votes
1answer
168 views

quantile calculation in qgis

I have a simple question about the graduated classification in qgis (version 2.0.1). I can choose between several statistical methods to classify my data (standard deviation, quantile, natural ...
0
votes
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 ...
9
votes
1answer
2k views

Permanently Change ArcMap's “Maximum Sample Size” Setting?

I've lately been working on feature classes with a huge number of polygons (e.g. all of the Census blocks within the Chicago metro area). I've been needing to symbolize them by quantities a fair ...
2
votes
1answer
1k views

How to automatically export multiple maps with quantile symbology in ArcGIS Desktop?

I am a relatively new ArcGIS user and I have a question about automating a tedious join/symbology classification/export operation. I have a very simple shapefile to which I join a bunch of fields. I ...
1
vote
1answer
32 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
0answers
35 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 ...
1
vote
1answer
19 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
votes
1answer
41 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?
3
votes
1answer
175 views

Unsupervised classification with kmeans in R

I have a time series of satellite images (5 bands) and want to classify them by kmeans in R. My script is working fine (loop through my images, convert the images to data.frame, cluster them, and ...
0
votes
0answers
24 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 ...
0
votes
0answers
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 ...
1
vote
1answer
48 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 ...
3
votes
2answers
95 views

How to change class break schemes in QGIS to eliminate overlap

When using Graduated Symbology in QGIS, by default the bounds seem to be overlapping. For example, class 1 shows 0-100.000; class 2 shows 100.000-200.000; class 3 shows 200.000-300.000 where it ...
0
votes
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' ...
0
votes
0answers
9 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.
1
vote
0answers
17 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
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 ...
1
vote
1answer
103 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 ...
6
votes
2answers
218 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
59 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 ...
1
vote
0answers
85 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 ...
9
votes
5answers
7k views

Source for high-resolution satellite images free/low-cost?

I am doing a household survey in Kenya, and I need to ensure that my survey team visits every house within a given area. I've been going to google maps and right-clicking on roofs to get coordinates ...
1
vote
0answers
40 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 ...
0
votes
1answer
79 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 ...
3
votes
1answer
123 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
votes
0answers
63 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 ...
0
votes
0answers
18 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 ...
3
votes
2answers
197 views

Spatial Classification

I am not sure what to call my problem. From this image, I have a set of classified polygons (colored). I would like a way to classify the white polygons in the image. I don’t have any attributes to ...
3
votes
1answer
106 views

Correcting class codes of LiDAR files in ArcGIS

Is there any procedure to automatically correct lidar classification? My LAS Dataset has water listed as ground and buildings listed as vegetation. Just wondering if there is any option to fix this. ...
3
votes
2answers
62 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
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 ...
0
votes
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 ...
0
votes
0answers
27 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
vote
1answer
79 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 ...
1
vote
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 ...
3
votes
2answers
581 views

Shapefile Conversion to ERDAS Signature editor

I'm trying to run a supervised classification for an image. I was working with it in ArcMap and created some training data. I wanted to see if I could get a better result with Erdas Imagine using the ...
1
vote
2answers
86 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 ...
6
votes
3answers
334 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: ...
2
votes
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 ...
1
vote
1answer
88 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 ...
1
vote
1answer
259 views

Creating color table file in PCI Geomatica

What is the simplest way to create a stand-alone color-table file in PCI Geomatica (PCT or STR)? I have some classified imagery with values ranging between 0-255 and I would like a way to ...
9
votes
2answers
268 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, ...
2
votes
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
votes
0answers
63 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 ...