Supervised Classification | Google Earth Engine | Google for Developers
remote-sensingclassificationgoogle-earth-enginemachine-learninggeospatial
Abstraction: Google Earth Engine supervised classification workflow using CART, RandomForest, and SVM
Key points:
- Earth Engine Classifier package supports CART, RandomForest, NaiveBayes, and SVM (via libsvm); training data must be a FeatureCollection with consecutive integer class labels starting at 0
image.sampleRegions()extracts predictor values from Landsat bands at training point/polygon locations- Six output modes available: CLASSIFICATION, REGRESSION, PROBABILITY, MULTIPROBABILITY, RAW, RAW_REGRESSION via
setOutputMode() - Accuracy assessment uses ConfusionMatrix; training accuracy overestimates true accuracy — validation split essential
- Spatial autocorrelation can inflate accuracy; spatial join filter removes training samples within 1000m of validation points
- Expensive classifiers can be exported as assets via
Export.classifier.toAsset()and reloaded to avoid retraining
Connections: Google · Supervised Learning · Classification · Random Forest · Support Vector Machines
Source: https://developers.google.com/earth-engine/guides/classification