euclideanDistance static method

double euclideanDistance(Float32List a, Float32List b)

Computes the Euclidean (L2) distance between two embedding vectors.

Euclidean distance measures the straight-line distance between two points. For face embeddings:

• Values < 0.6 strongly suggest the same person
• Values < 0.8 suggest the same person
• Values > 1.0 suggest different people

Note: Threshold values assume normalized embeddings.

Example:

final distance = FaceEmbedding.euclideanDistance(embedding1, embedding2);
if (distance < 0.6) {
  print('Very likely the same person');
}

Implementation

static double euclideanDistance(Float32List a, Float32List b) {
  if (a.length != b.length) {
    throw ArgumentError(
      'Embedding dimensions must match: ${a.length} vs ${b.length}',
    );
  }

  double sum = 0.0;
  for (int i = 0; i < a.length; i++) {
    final double diff = a[i] - b[i];
    sum += diff * diff;
  }
  return math.sqrt(sum);
}