Triplet loss

• Given an achor, pull similar closer and push dissimilar away
• Face recog FaceNet
• Anchor, positive sample are neigbors while neg isnt
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• For each triplet, this condition must hold $$||f(x^a) - f(x^p)||^2 + \alpha \gt f(x^a) - f(x^n)||^2$
• $\alpha$ is a margin b/w positive and neg
• loss to minimize $$L(\theta) = \Sigma_i^n||f(x^a) - f(x^p)||^2 + f(x^a) - f(x^n)||^2 + \alpha$
• Harmonic Triplet Loss