Scrubbing (audio)

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In digital audio editing, scrubbing is an interaction in which a user drags a cursor or playhead across a segment of a waveform to hear it. [1] Scrubbing is a convenient way to quickly navigate an audio file, and is a common feature of modern digital audio workstations and other audio editing software. The term comes from the early days of the recording industry and refers to the process of physically moving tape reels to locate a specific point in the audio track; this gave the engineer the impression that the tape was being scrubbed, or cleaned.

Contents

Implementations

Common scrubbing feedback techniques include: [2]

Resampling
allows playback at arbitrary rates, which also pitch-shifts the audio, approximating the effect of playing audio from an analog source like tape or vinyl with a similarly varying motion
Cut-and-paste
the original signal is segmented into frames of constant width and playback is obtained by either discarding (time compression) or repeating (time expansion) some frames. [3]
Timeline stretching
processes the audio to allow playback at arbitrary rates without changing the pitch (audio time stretching), common approaches include: [4] the Phase Vocoder, and Time Domain Harmonic Scaling

See also

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References

  1. Salvucci, Keith (March 25, 2004). "Audio scrubbing". Patent US 2005/0216839 A1.
  2. Lee, Eric; Karrer, Thorsten; Borchers, Jan (2007). "Improving Interfaces for Navigating Continuous Audio Timelines" (PDF).
  3. Couvreur, Laurent; et al. (March 2008). Dutoit, Thierry; Macq, Benoît (eds.). "Audio Skimming" (PDF). QPSR of the numediart research program. Vol. 1, no. 1.
  4. Bernsee, Stephan M. (2005). "Time Stretching And Pitch Shifting of Audio Signals - An Overview" (PDF).