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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8
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3answers
5k views

Best 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
2answers
38 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
1answer
128 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 ...
3
votes
1answer
38 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. ...
3
votes
1answer
84 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 ...
3
votes
1answer
116 views

Classified Images of RandomForest-Classification look clustered

I performed a RF-classification. I have 6 bands, ~250 trainingpoints in a shapefile, OOB estimate of error rate: 1.56% Picture of take trainingpoints added. My code: ...
2
votes
1answer
67 views

From where I can get 4-band satellite imagery of Sweden?

I'm looking for good quality, fine resolution 4-band satellite photos of Sweden for academic use (and I'm willing to pay for it). What I'm after is as detailed as possible photos of certain part of ...
1
vote
1answer
47 views

Signature File Creating Issues

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, ...
1
vote
1answer
53 views

Extraction of pixels from layerstacked NDVI image

How do I get rice pixels only from layerstack NDVI (modis) or SASI image? I also have a thematic rice image Please tell me how to do in erdas.
0
votes
1answer
18 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 ...
3
votes
0answers
36 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 ...
3
votes
0answers
41 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 ...
3
votes
0answers
79 views

How to use WEKA J48 classifier for satellite image classifications

Basically I am trying to build a tool from WEKA software using the J48 classifier for automatic satellite image classification to build landuse land cover maps. Could somebody please help, as I am not ...
3
votes
0answers
130 views

ISOdata classifier in QGIS?

Is there a function that produces an ISODATA unsupervised classification in QGIS? The only unsupervised classification function I can find is a KMeans.
3
votes
0answers
396 views

What is the convergence threshold for ArcGIS Iso Cluster?

The ArcGIS tool Iso Cluster Unsupervised Classification does not seem to have any documentation on the convergence threshold used in the tool. To compare, Erdas Imagine has all of the necessary ...
2
votes
0answers
111 views

Data Driven Pages - Dynamic Legend Classifications - Change with data frame extent

I am creating choropleth maps for quantified data. Each DDP will focus on a new county, which is shown by using a clip of the data frame (by the county boundary). I want to define quantified legend ...
2
votes
0answers
79 views

QGIS 2.2.0-Valmiera 64bit on windows 8.1 displays error while creating ROI in SAC plugin

I don't know what happened while creating ROI during Classification using Semi automatic Classification Plugin 3.1.0 "Rome" installed on hp Pavillion i7 with windows 8.1 When i started to generate ROI ...
2
votes
0answers
35 views

ASTER mineral indices with VINR and SWIR data

I need to run a supervised classification on ASTER data in order to map a rock formation, which is composed of chert. There is no shortage of indices which can be used to highlight silica rich ...
2
votes
0answers
73 views

R: Can raster predict function pass to predict.rfsrc (a prediction function in a parallel verion of RandomForest)?

It seems that raster predict function can pass to predict.randomForest by setting the "type='response'". I am using a parallel version of randomForest package called the "randomForestSRC" and I am ...
2
votes
0answers
40 views

differentiating stone houses from barren rock in ArcGIS 9.3

I'm working in ArcGIS 9.3 trying to differentiate stone houses (often red brick roofs) from barren rock in a typical Mediterranean karst region via remote sensing. I have been using Landsat imagery. I ...
2
votes
0answers
125 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 ...
2
votes
0answers
183 views

Image classification for a study site falling over two adjacent Landsat 8 scenes (qGIS or ArcGIS)

This question concerns work-flow rather than specific methodological problems. I will be using GRASS to classify Landsat 8 images to create a vegetation map for a study site that happens to fall over ...
2
votes
0answers
88 views

Flood extent extraction from satellite images

How i can extract the floodwater from satellite images? Is the image classification method accurate for moderate-resolution satellite (Terra/Aqua MODIS)? Or is there a more accurate methods? Thanks.
2
votes
0answers
432 views

ISODATA unsupervised classification in ArcMap 10.1

I’m doing a project on landsat 5 images. I’ve composited the images into 1 raster, and I want to classify the raster with ISODATA Unsupervised Classification. How do I calculate the best number of ...
1
vote
0answers
33 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 ...
1
vote
0answers
71 views

Comparing unclassified super-objects with classified sub-objects

I have two shapefiles exported from ecognition. the first shapefile contains the land cover classification and the 2nd one contains unclassified superobjects of the 1st shapefile. I want to compute ...
1
vote
0answers
41 views

How to batch classify a multi-temporal raster image stack?

I am using dense time stacks of remotely sensed imagery to analyse vegetation change in the Arctic from 1984-2010 for one scene. I will be needing to classify each image, likely using the Maximum ...
1
vote
0answers
24 views

Reclassify based in neighbour polygons

I would like to do a simple operation in QGIS and I am not sure about which is the best option. I have a polygon shapefile and each one has one class attached. I want to reclassify one of them based ...
1
vote
0answers
139 views

where to perform principal components analysis and tasseled cap transformation

I want to perform a principal components analysis (pca) and a tasseled cap transformation (tasscap) for a classification.Should i perform pca and tasscap on the original bands of my image or on the ...
1
vote
0answers
121 views

Segmentation Violation in ArcView 3.1 while performing UpdateLegend?

I am loading a ".avl" legend file into ArcView 3.1 and I am plagued with a recurring Segmentation Violation Error when I execute the updatelegend command in the theme. It looks like the legend file ...
1
vote
0answers
91 views

From classified image to topology in ArcInfo

I have some coastal 4 band imagery that I have classified to designate land, water, and undetermined. I want to convert this to polygons with topology, and significantly simplify the polygons. If I ...
0
votes
0answers
22 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
0
votes
0answers
121 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 ...
0
votes
0answers
28 views

Semi-Automated Classification Plugin ROI Creation Failure

I can't get the Region-growing to work when running the ROI creation module. What am I missing? Please see the "AttributeError" line halfway down: # An error has occured while executing Python ...
0
votes
0answers
83 views

OBIA following connected components segmentation in Monteverdi2

New to Monteverdi2 and OTB. I just finished a connected components segmentation using the Segmentation module and the large-scale vector output mode for large datasets. How can I filter the output ...
0
votes
0answers
21 views

Industries Database - EPRTR?

I am looking for a coherent , complete (At least EU coverage) and reliable (spatial accuracy) databse for INDUSTRIES I have been checking EPRTR database. Basically, it shows around 24,000 industrial ...
0
votes
0answers
34 views

How do you assign classes to percentage data in a data layer?

As a learning project I need to coneptualize a GIS output for assigning classes to data in a raster layer. In this case i have the unemployment rates for relevant magisterial districts in my ...
0
votes
0answers
47 views

ArcGIS Server Rest API Export with Class Breaks

I'm trying to export a map of a dynamic layer with class breaks. I can export the dynamic layer like this: $mapURL = ...
0
votes
0answers
32 views

Method of extracting the intersecting areas of multiple overlapping polygons (5) and classifying intersects based on spatially joined points

I have concave hulls surrounding clusters of data points which has led me to a lot of overlap and fuzzy boundaries. I am attempting to intersect the overlapping areas but have a minimum of 5 different ...