커버곡 식별

Cover-song identification detects different performances of the same composition. Traditional audio fingerprints are often designed to match near-identical recordings; substantial changes in tempo, key, arrangement, or production can make those fingerprints less useful. Chroma or harmonic pitch-class features summarize energy across twelve pitch classes and collapse octaves, which can reduce sensitivity to octave and some timbral changes, but they are not invariant to every instrumentation or arrangement change. A single global chroma summary can also lose temporal order, so comparing local chroma sequences can preserve melodic and harmonic progression. Older methods align those sequences using cross-correlation or dynamic time warping. Learned systems can produce fixed-dimensional representations for tracks of differing lengths, as in temporal-pyramid-pooling approaches, but retrieval quality and catalog-scale performance depend on the model, index, and evaluation.