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Model data augmentation

Data augmentation creates randomized variants of training spectra. It is disabled by default and affects training inputs, not validation, testing, or inference inputs.

Open a draft model version and select Overview > Advanced Settings > Data Augmentation. Set Enable data augmentation to Yes, then configure one or more methods.

Available methods

MethodEffectControls
Random CutoutSets one contiguous band-value segment to zeroProbability, Mask size
Smooth SignalApplies a moving-average filter along band orderProbability, Window size
Scale SignalMultiplies a spectrum by one random factorProbability, Scale min, Scale max
ZScore NormalizeStandardizes each selected spectrum independentlyProbability
Min Max NormalizeRescales each selected spectrum independently to 0-1Probability
Shift SignalCircularly rolls values along band indices without changing wavelengthsProbability, Shift max
Add NoiseAdds Gaussian noise scaled by the spectrum meanProbability, Noise factor
Flip SignalReverses band-value order without changing wavelengthsProbability
Magnitude WarpMultiplies values by a smooth random curveProbability, Sigma, Knot
Window SliceCrops a contiguous band window and resizes it to the original length without changing wavelengthsProbability, Reduce ratio
Baseline WanderAdds a sinusoidal baseline over normalized band orderProbability, Magnitude, Frequency

Each probability controls how often that method is applied to an eligible training example. Multiple enabled methods can be applied to the same example.

Use augmentation safely

  1. Start from a model with a documented validation baseline.
  2. Add methods that represent variation your sensor or acquisition process can plausibly produce.
  3. Change a small number of controls at a time.
  4. Compare validation metrics and spatial predictions with the same evaluation data.

Aggressive transformations can erase diagnostic features or create physically implausible spectra. More augmented variation is not automatically better.

Shift Signal, Flip Signal, and Window Slice move spectral features relative to the unchanged wavelength metadata. Circular wraparound, reversed spectral order, and stretched band windows are generally not physically plausible acquisition effects for wavelength-calibrated hyperspectral data. Avoid these methods unless a task-specific study validates the exact distortion. Random Cutout also writes zeros rather than a missing-data mask; use it only when that representation matches the intended robustness test.