DigiDesign Pro Tools, Reference Manual

Page: 549 / 886

Chapter 24: Beat Detective 535
Chapter 24: Beat Detective
Beat Detective is a powerful tool for analyzing,
editing, and manipulating audio or MIDI tracks
that have an inherent rhythmic character.
Beat Detective analyzes an audio or MIDI selec-
tion, identifies its peak transients or accented
notes, and generates
beat triggers based on the
detected peak transients or MIDI notes. From
these beat triggers, Beat Detective can:
• Extract tempo and beat information to create
Bar|Beat Markers that can be used to define
the session’s tempo map. See “Generating
Bar|Beat Markers with Beat Detective” on
page 545.
• Extract tempo and groove information as
groove templates, called DigiGrooves. These
templates can be applied to audio or MIDI us-
ing Beat Detective or Groove Quantize (see
“DigiGroove Templates” on page 546.
• Separate an audio selection into discrete re-
gions, and then conform (or “quantize”) sep-
arated regions to the session’s tempo map, or
to groove templates. See “Separating Regions
with Beat Detective” on page 548 and “Con-
forming Regions with Beat Detective” on
page 550.
Beat Detective and Source Material
Beat Detective is most effective with audio or
MIDI that has clear attack transients or accent
patterns (including most instruments used in
popular music, such as drums, guitar, or bass).
Beat Detective will be less successful with audio
material with soft attacks, or legato phrasing
(such as strings and vocals).
Uses for Beat Detective
Beat Detective can be useful in many situations,
including:
Extracting Tempo from Audio
Beat Detective can
generate Bar|Beat Markers, from which it can ex-
tract the tempo—even if the audio contains
varying tempos, or material with a swing feel.
Additionally, once Bar|Beat Markers have been
generated, other audio and MIDI regions can be
quantized to them.
Creating DigiGrooves
Beat Detective can extract
groove templates, called DigiGrooves, from an
audio selection. DigiGrooves can be used to ap-
ply the groove, or feel of the captured passage to
other audio selections (using Groove Conform)
or MIDI data (using Groove Quantize).
Conforming Audio Regions
Beat Detective can
conform (“quantize”) audio with a different
tempo, or with varying tempos, to the session’s
current tempo map, or to a groove template.