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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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
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 ...
2
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2answers
49 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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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. ...
1
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1answer
39 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
45 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
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 ...
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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
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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 ...
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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 ...
7
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2answers
165 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
44 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
79 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 ...
1
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1answer
32 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
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 ...
2
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1answer
39 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
114 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 ...
5
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3answers
165 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
220 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 ...
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0answers
72 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 ...
3
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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 ...
1
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1answer
52 views

Remove cell boundaries of raster pixels converted to vector format

I have a solar radiation shapefile with 10 km x 10 km cells. When I put it on QGIS, many pixels with boundaries take place. Please see the following image: How can I remove them in Qgis?
0
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1answer
40 views

Classifying type of land use each spectral represents from remote sensed data?

How do you know the type of land use each spectral represents from an remote sensed data into a classification ? Which classification is the most typical to use when doing that ? How many ...
2
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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
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2answers
73 views

How to filter by Selected Objects in eCognition?

I was wondering if there is any options in eCognition Developer to filter by selected objects. Suppose if I select some objects with polygon selection tool and want to use 'assign class'. In the ...
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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
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1answer
55 views

Feature extraction in remote sensing!

Which are the most common features in order to perform a supervised classification in remote sensing? Furthermore anyone worked with SAR features? Which are the most commonly used? Can anybody suggest ...
1
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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
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3answers
247 views

Pixel-based and object-based classification!

I would like to understand if pixel-based classification algorithm (e.g. Maximum Likelihood classification ) can be used for object-based classification (i.e. after a segmentation procedure). On the ...
6
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2answers
188 views

what's the difference between spectral signature and features in remote sensing?

I would like to understand if is there any difference or relation between spectral signature concept and features in remote sensing?
3
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1answer
88 views

QGIS Quantile method

I have a question about the quantile classification in QGIS (2.6 and master, windows or linux). I used the points in polygon fonction. I have 100 polygons. In the attributes of my 100 polygon I get ...
0
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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 ...
2
votes
1answer
156 views

Workflow of Processing Landsat data for landcover classification

I have downloaded Landsat-8 data to make a land-use raster. So far I've made a composite image and clipped it by my study area. As you can see, there is some slight cloud cover. I've gone ahead and ...
6
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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 ...
2
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1answer
31 views

Determine mudflats area from remote sensing images

I need to determine the mudflat area for a group of small islands in the Red Sea. I have read some publications and it seems to be possible using remote sensing, for example Landsat. But I am not ...
3
votes
2answers
327 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
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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.
2
votes
1answer
95 views

Possible to use same signature file to classify images from different years?

I have Landsat images for the same area over 20 years (one photo per year in same season). I would like to detect changes occured in forested area like clear-cut and bark beetle outbreak over time. I ...
4
votes
1answer
286 views

QGIS 2.4.0 Chugiak How to remove topographic effects like shadows from landsat image

I am using QGIS 2.4.0 Chugiak on my windows 8.1, for classification of landsat 5-7 image that contains hilly mountains with dense forest and 60% area are plains. I am classifying through ...
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 ...
2
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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 ...
3
votes
1answer
146 views

Standard Terminology for User's and Producer's Accuracy

In the literature I see terms such as, User's accuracy Pr( Y = c | X = c); Producer's accuracy Pr( X = c | Y = c); where X is the estimator of a particular land use, Y is the random variable ...
1
vote
1answer
70 views

Reclassification of raster surface using ArcGIS for Desktop?

I have a raster surface with values ranging from 0 -100. I want to create a categorical classification (percentage categories of 5%, e.g. 0-5%, 6-10%...) and reclassify my surface into these ...
2
votes
2answers
178 views

Standard deviation classification in QGIS

Is it possible to implement Standard deviation classification in QGIS symbology of a layer like in ArcGIS: http://webhelp.esri.com/arcgisdesktop/9.3/index.cfm?TopicName=Standard_deviation I need to ...
5
votes
3answers
260 views

How to generalize training data for a random forest classifier?

I am working with a random forest classifier in eCognition (new with eCognition 9.0). The image shows 8 NAIP tiles I am attempting to classify using approximately 100 training points. The training ...
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
1answer
107 views

How to improve classification accuracy for 3-band (RGB) imagery?

I am hoping to extract some simple vegetation features (sagebrush) from 1m 3-band (RGB) NAIP imagery. Unfortunately, there is no near-infrared band available for this dataset and I need to use this ...
3
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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
1answer
61 views

Is there another way to acces the histogram in ArcGis 10

i need the histogram of the frequency to heights distribution like in the attached picture. Is there another toolkit to access this data? A screenshot is not suitable :) The attribute table is not ...
4
votes
1answer
67 views

Is it possible, and if so how, to effectively classify vegetation types using false near infra red imagery?

Background : I use near infra-red imagery to delineate wetlands and water bodies with good success. It's also obvious to distinguish between new healthy vegetation and older growth and land areas with ...