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US 5,256,832 AGranted
Beat detector and synchronization control device using the beat position detected thereby
AssigneeCasio Computer Co., Ltd.
InventorAtsushi Miyake
Life of this patent
Estimating the term…
Abstract
A reference start point RPS and a reference end point RPE for detecting a beat position BP.sub.n are set as a BP.sub.n-1 +BT.+-.DR on the basis of a beat interval BT obtained by user's guide tapping for a predetermined time, a predetermined deviation value DR and the detected last beat position BP.sub.n-1. Thus, the crest value Lrp of an audio signal exceeding a predetermined threshold TH in the specified retrieval interval is obtained. Each beat position BP.sub.n is obtained on the basis of a reference point RS of the audio signal existing when the crest value is obtained. In reproduction of an audio signal by a DMTR, a MIDI clock is generated from the beat position and output to a MIDI sequencer, etc.
Claims18
A beat detector comprising:
- audio recording and reproducing means for recording and reproducing an audio signal and including storage means for recording the audio signal;
- head beat position designating means, operable by a user, for designating a head beat position in the audio signal recorded in said storage means;
- beat timing designating means, operable by a user, for designating each beat timing for a predetermined interval of the audio signal while causing said audio recording and reproducing means to reproduce the audio signal;
- reference beat interval calculating means for calculating a reference beat time interval for one beat from the beat timings designated by said beat timing designating means;
- and
- beat position detecting means for detecting each beat position on the basis of a reproduction position where a value related to the amplitude of the audio signal exceeds a predetermined threshold in a retrieval interval of a predetermined range the center of which is a reproduction position advancing by the reference beat interval from an already obtained beat position using the head beat position as an initial value in the audio signal recorded in said storage means.
3 more elements
A beat detector comprising:
- audio recording and reproducing means for recording and reproducing an audio signal and including storage means for recording the audio signal;
- head beat position designating means, operable by a user, for designating the head beat position in the audio signal recorded in said storage means;
- beat timing designating means, operable by a user, for designating each beat timing for a predetermined interval of the audio signal while causing said audio recording and reproducing means to reproduce the audio signal;
- reference beat interval calculating means for calculating a reference beat time interval for one beat from the beat timings designated by said beat timing designating means;
- and
- beat position detecting means for detecting each beat position on the basis of a reproduction position where a value related to the amplitude of the audio signal exceeds a predetermined threshold in a retrieval interval of a predetermined range the center of which is a reproduction position advancing from an already obtained beat position by an average beat interval which uses as an initial value the reference beat interval directly before the already obtained beat position, using the head beat position as an initial value in the audio signal recorded in said storage means.
3 more elements
A synchronization controls device comprising:
- audio recording and reproducing means for recording and reproducing an audio signal and including storage means for recording the audio signal;
- head beat position designating means, operable by a user, for designating the head beat position in the audio signal recording in said storage means;
- beat timing designating means for causing the user to designate each beat timing for a predetermined interval of the audio signal while causing said audio recording and reproducing means to reproduce the audio signal;
- reference beat interval calculating means for calculating a reference beat time interval for one beat from the beat timings designated by said beat timing designating means;
- beat position detecting means for detecting each beat position on the basis of a reproduction position where a value related to the amplitude of the audio signal exceeds a predetermined threshold in a retrieval interval of a predetermined range the center of which is a reproduction position advancing by the reference beat interval from an already obtained beat position, using the head beat position as an initial value in the audio signal recorded in said storage means;
- musical instrument control means for controlling a musical instrument;
- timing signal generating means for generating a timing signal corresponding to each of timings at which an interval from each beat position to the next beat position is divided into equal subintervals while causing said audio recording and reproducing means to reproduce the audio signal;
- and
- timing signal outputting means for outputting to said musical instrument control means a timing signal corresponding to said last-mentioned timings to thereby synchronize the operation of said musical instrument control means with the reproduction of the audio signal by said audio recording and reproducing means.
6 more elements
A synchronization control device comprising:
- audio recording and reproducing means for recording and reproducing an audio signal and including storage means for recording the audio signal;
- head beat position designating means, operable by a user, for designating the head beat position in the audio signal recorded in said storage means;
- beat timing designating means, operable by a user, for designating each beat timing for a predetermined interval of the audio signal while causing said audio recording and reproducing means to reproduce the audio signal;
- reference beat interval calculating means for calculating a reference beat time interval for one beat form the beat timings designated by said beat timing designating means;
- beat position detecting means for detecting each beat position on the basis of a reproduction position where a value related to the amplitude of the audio signal exceeds a predetermined threshold in a retrieval interval of a predetermined range the center of which is a reproduction position advancing from an already obtained beat position by an average beat interval which uses as an initial value the reference beat interval directly before the already obtained beat position, using the head beat position as an initial value in the audio signal recorded in said storage means;
- musical instrument control means for controlling a musical instrument;
- timing signal generating means for generating a timing signal corresponding to each of timings at which an interval from each beat position to the next bat position is divided into equal subinterval while causing said audio recording and reproducing means to reproduce the audio signal;
- and
- timing signal outputting means for outputting to said musical instrument control means a timing signal corresponding to each of said last-mentioned timings to thereby synchronize the operation of said musical instrument control means with the reproduction of the audio signal by said audio recording and reproducing means.
6 more elements
Dependencies are inferred from the claim text.