Triplet Loss

Definition

Triplet loss is a Loss Function where a reference input (anchor) is compared to a matching input (positive) and a non-matching input (negative). The distance from the anchor to the positive is minimized, and the distance from the anchor to the negative input is maximized.

$L=\sum _{i=1}^n[||f(x_i^a)-f(x_i^p)|{|}_2^2-||f(x_i^a)-f(x_i^n)|{|}_2^2+\alpha {]}_{+}$ where $\alpha$ is a margin between positive and negative pairs