DETECTING DISTORTED AUDIO SIGNALS BASED ON AUDIO FINGERPRINTING

摘要

An audio identification system generates a probe audio fingerprint of an audio signal and determines amount of pitch shifting in the audio signal based on analysis of correlation between the probe audio fingerprint and a reference audio fingerprint. The audio identification system applies a time-to-frequency domain transform to frames of the audio signal and filters the transformed frames. The audio identification system applies a two-dimensional discrete cosine transform (DCT) to the filtered frames and generates the probe audio fingerprint from a selected number of DCT coefficients. The audio identification system calculates a DCT sign-only correlation between the probe audio fingerprint and the reference audio fingerprint, and the DCT sign-only correlation closely approximates the similarity between the audio characteristics of the probe audio fingerprint and those of the reference audio fingerprint. Based on the correlation analysis, the audio identification system determines the amount of pitch shifting in the audio signal.

主权项

1. A computer-implemented method comprising:
receiving an audio signal including a plurality of frames, each frame representing a portion of the audio signal; generating a probe audio fingerprint based on one or more of the plurality frames; selecting a reference audio fingerprint from a plurality of reference audio fingerprints; calculating a correlation between the probe audio fingerprint and the selected reference audio fingerprint, the correlation approximating similarity between audio characteristics of the probe audio fingerprint and audio characteristics of the selected reference audio fingerprint; and determining whether the probe audio fingerprint matches the selected reference audio fingerprint based on the correlation between the probe audio fingerprint and the selected reference audio fingerprint.