Questions tagged [image-classification]
Image classification refers to the task of extracting information classes from a multiband raster image.
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Object-based classification issues on ArcGIS Pro
I am currently building a predictive wetland layer using Sentinnel-2 bands (RGB and Infrared), and several LiDAR derived datasets. I made a 8 band composite and have been training the model using the ...
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Train images classifier not working on orthomosaic GeoTIFF file
When I run the train images classifier on an orthomosaic or orthophoto by OTB in QGIS it generates me not just a file with .txt extension but by default it starts generating .txt.shp, .txt.shx, .txt....
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How to do post-classification / eliminate isolated pixels in Google Earth Engine
I am trying to apply post-processing (Classification Sieve) in GEE to my classified raster, just as we apply in QGIS (used 4x4) or (8x8). Remove unwanted and noise pepper effects from the ...
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How to Fix: Layer error: Computed value is too large in Google Earth Engine
I conducted a landcover classification, distinguishing between mangrove and non-mangrove areas. For each landcover type, I gathered fewer than 10 samples. I utilized Random Forest (RF) for ...
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Image Overlay for Classified Images
I created 5 classified images for year 2019-2023 as shown: -
Fig: Classified image of Sentinel-2 for 2019
I have also prepared the classified image for 2020, 2021, 2022, 2023 like above. The ...
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How to enable the image classification tool in ArcGIS
I intend to perform a supervised classification on a TIFF image in ArcGIS 10.8. The image is an imagery of an area which I downloaded from my ArcGIS Online account. The goal is to automatically ...
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How to use Spectral Temporal Metric (reducers) in Supervised Random Forest Classification in GEE
I am trying to improve image classification in GEE by using the STM of the mean.
I first calculated the mean of the four bands.
Then I added the new column with mean to the image.
Then I used the new ...
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Supervised classification from collocated Sentinel 1 and 2 image
I was trying to perform a supervised classification of a mangrove forest using collocated sentinel 1 and 2 images using this code. With the help provided by @Xunilk, I finally managed to run the code. ...
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Performing image classification with both a classifier definition file and a segmented image in ArcGIS Pro
I am performing object-based classifications in ArcGIS Pro in the form of two separate rounds of classifications.
In the first round, I obtained a drone image and uploaded it to GIS, I manually ...
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What do the values in trees of Random forest GEE mean?
I get these trees in GEE:
trees: List (29 elements) 0: n= 116838
node), split, n, loss, yval, (yprob)
* denotes terminal node
1) root 116838 31180 8 (0.010997 0.0066155 0.019316 0.013984 0.012195 ...
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GEE: Finding number of classified pixels for entire image collection (Sentinel 2)
I'm trying to calculate the number of pixels classified as ice for every image in my Sentinel 2 collection, but when I try to map my function over all the images, each feature in my test export has ...
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*Image* prediction with GEE AI Platform and gradient boosted tree model
I am attempting to build a crop classifier with training data from Sentinel-2 imagery over several seasons. I want to use a gradient boosted tree model instead of a neural net.
There are many examples ...
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How to use existing polygon feature class as training samples in ArcGIS Pro Classification Wizard?
I have created a polygon feature class from field observations at specific locations. I renamed the attribute table field containing the classes to "classname" as this seems to be important ...
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GEE Code Error in Classification of Sentinel 2
My goal is to come up with a heavy metal classification map using Sentinel 2 images by applying Random Forest. The heavy metal training data is a set of points saved as a .csv file in a column ...
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FeatureCollection (Error) Array: Max (NaN) cannot be less than min (NaN)
I am trying to do Object base Image classification, but my code giving me this error, I tried to fix it but nothing worked.
This is an error, "FeatureCollection (Error)
Array: Max (NaN) cannot be ...
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Perform the accuracy assessment after performing classification on an image collection in GEE
I have classify an image collection using Random Forest classification method by creating a function and mapping that function over image collection. Now, I am stuck with accuracy assesment. Because ...
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Error: Computation timed out. (Error code: 3)
I am trying to perform Object base Image Classification, but it giving me this error, "Error: Computation timed out. (Error code: 3)". I tried to change the scale but this also not worked.
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Class disparition after using a classifier in SCP plugin for a classification
I use a classifier in SCP plugin for a classification. I don't have any problem for load and the treatment works. However, my first class disappears for each test. For example, if my classifier ...
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Accuracy assessment 0.99% Google Earth Engine
I've successfully run my classification using Landsat but my accuracy gives me 0.99 which might be too good to be true. Here is my script. What might the problem be?
//Define AOI and predefined ...
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No valid data training when doing a supervised classification using training data from a different year
I'm doing a supervised classification using training data from a 2023 Image to a 2022 Image. However, when doing the migration I got the error message "No valid training data were found" for ...
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Missing features in FeatureCollection in Google Earth Engine
I am working on a project where I cross-classify several regions with each other. In other words: I train several classifiers on imagery from different regions and classify all images of all regions ...
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Apply single label image classification in Google Earth Engine
I am trying to apply single label image classification in Google Earth Engine in the context of Bragg Scattering. What I'm trying to do comes down to the following: Assign a single label (e.g. Bragg ...
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Google Earth Engine: How do I create a feature collection with bounded, randomly-assigned classes?
Here's an example script: https://code.earthengine.google.com/d511144dde609f4cf1fd8607499e2026
I would like to create a set of random points with random classes to use as training data in order to ...
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Classify pixels using deep learning model outputs blank raster
I have been attempting to classify 0.5 m resolution imagery for my research. Unfortunately, when I go to run the "classify pixels using deep learning tool", I get an output with no errors, ...
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QGIS dzetsaka plug-in for satellite image classification error how to do?
When I used dzetsaka plug-in of QGIS to process the SAR image of Gaofen No. 3 satellite, I wanted to use Gaussian mixture model and random forest for classification according to the different ...
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Classify georeferenced image based on colour in QGIS
I have a georeferenced image (attached) that I want to classify into a raster, where raster values correspond to the colours in the image.
Low (green) = 1
Medium (yellow) = 2
High (red) = 3
All other ...
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Calculate accuracy assessment for MNDWI classified image (Overall accuracy, Kappa)
I want to find a way to calculate the accuracy assessment for a classified image (classified by mndwi threshold). I already had the classified image and the reference water body in shapefile format ...
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Band Combination for NIR-R-G in Landsat 7 scene
What is the order for the band combination to show Landsat7 scene in NIR-R-G Band? The band combination I used is:-
And the result generated is:-
Is this the correct layer combination to show ...
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Classify Land Use Land Cover
I am asked to classify an image (Landsat 7 scene) for 2 different time period one for the month of July (Image 1) and the other December (Image 2) as shown below.
Image for the month of July
Image ...
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Classifying Object Based on Mean IR Values
While Developing rule sets using e-Cognition for object classification for say; Landsat 7 images what are the threshold conditions to classify water, building, agriculture land & bare soil ...
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How do I ignore artificial landscape (e.g., pavement, cars, buildings) in order to classify features of the natural landscape (e.g., veg cover, soil)? [closed]
I want to classify the landscape into different classes, in order to identify areas with low veg cover and bare soil. Unfortunately, any of the classification tools I use will recognize pavement, cars,...
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Supervised Classification gives "Directory(error)" ans "SR_B1" missing error in GEE
I am trying to run supervised classification on single date, cloud free, Landsat 5 collection 2 level 2 image. I have imported the point shapefiles of different classes with class values and have ...
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Classify the image by a field in its attribute table using QGIS software
I created the attribute table of raster data in ArcMap software. There is a field that I added in the attribute table that I created. I can reclassify the image using the field I added to the image's ...
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Issue in applying condition expression to all band values in Google Earth engine
I want to apply the following condition statement to all the pixels of an indices image having only 1 band. The condition is as follows-
For that first I have calculated the mean value of my image. ...
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Is there a way to obtain the variable importance for a specific class in Earth Engine?
I used a .smileRandomForest() and I know that by calling .explain() you can see the relative importance of the variables for the general classification... but I would like to know which inputs ...
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Using values of a groups of objects to create an image in GEE
I have calculated the 90th percentile for each class of land cover using the reducer ee.Reducer.percentile([90]).group
The result is a group of objects and I don’t know how to use it.
I would like to ...
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R RStoolbox not picking up a SpatialPolygonDataFrame as a Polygon
I am trying to perform a supervised classification via RStoolbox. I am using a SpatialPolygonDataFrame as the training data. Now, even though rgdal picks up the polygon, RStoolbox returns an error.
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Calculate transition of different NDVI classes from pre and post NDVI in Google Earth Engine
My competency in GEE is quite low. I have calculated 2 NDVI layers (pre and post-disturbance NDVI). I have separated these NDVI layers into 4 classes according to NDVI values. Now I need to calculate ...
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Google Earth Engine: summary statistics of an image by another image classified
I want to summarize the value from one image by the label provided by another classified image which only with two labels. But the reduceRegions function needs the FeatureCollection to provide the ...
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Fatal error using orfeo toolbox (otb 8.0.0) algorithm Computeconfusionmatrix in QGIS 3.22
I tried to compute a confusion matrix of a raster classification with otb's Computeconfusionmatrix using vector data (polygons) as reference input. When I run the same algorithm in mapla (otb ...
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Train Image Classifier (orfea): Could not load selected layer/table
When attempting to input vector data into the Orfea TrainImageClassifier, it shows the error: Could not load selected layer/table. Dependent field could not be populated.
This occurs when I attempt to ...
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How to classify tree cover overlapping roofs in eCognition
This might be a fairly simple question, but I'm new to eCognition. I'm using Developer 10.2. For canopy that overlaps rooftops, I need to define these areas as separate objects and classify as canopy.
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Maximum Likelihood Classification with No Output using ArcMap
I'm working on a project in ArcMap 10.7.1 and I'm having trouble with the Maximum Likelihood Classification function. I created four classes in my training sample manager (25 samples for 3 of the ...
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Exporting a classified image in GEE without getting a BLACK raster image
I have been trying to export this classified image. I want my GeoTIFF file to show this view...
But every time I export, my image turns out Black. after some digging i got to learn that I need to ...
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Manual classification combining bands and defining values in GEE
I would like to perform some manual classification on a single image of S1-data which is fairly simple: either a pixel is classified as 'Water', or it is classified as 'Land'. I did these ...
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Supervised Classification: determining Training & Validation Data Sample Sizes [closed]
How does one determine Training & Validation sample sizes for Supervised Classification?
My scenario: I'm using a previous year's classified map (2019) as an "a-priori" guide for picking ...
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Extracting polygons from scanned GeoRef images based on colours in QGIS
I would like to extract a polygon based on it's colour from a scanned map georeferenced in QGIS.
In the image, I would like to extract all of the blue as a separate shapefile/GeoPackage instead of ...
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Calculating area of single class in Google Earth Engine
I'm doing a research about evaluation of the effect of catastrophic forest fires in Yakutia in 2021. I did some classification of three different classes: 'burned_area', 'vegetation' and 'water'. Here'...
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Creating images by calculating other images
I have some categorical images (Y, T, Max, Min, MaxUp, MaxLo). Each image has integer values in different ranges.
I want to create an image MinUp that
MinUp = T when Max = MaxUp ...
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Reclassifying raster after image classification in ArcGIS Pro
In the ArcGIS Pro Imagery tab, there is the possibility to reclassify an image after classification to manually change misclassified pixels to their correct values, however, after doing this, my pixel ...