Sound signal analyzing device

• US 6,525,255 B1
• Filed: 11/19/1997
• Issued: 02/25/2003
• Est. Priority Date: 11/20/1996
• Status: Expired due to Fees

• Current Assignee: Yamaha Corporation
• Original Assignee: Yamaha Corporation
• Inventors: Funaki, Tomoyuki
• Primary Examiner(s): Donels, Jeffrey
• Application Number:
  US08/974,339
• Time in Patent Office: 1,924 Days
• Field of Search: 846/16, 846/54, 846/61, 816/16, 816/54, 816/61
• US Class Current: 84/616
• CPC Class Codes: G10H 2240/056 MIDI or other note-oriented file format
• CPC Class Codes: G10H 3/125 Extracting or recognising the pitch or fundamental frequency of the picked up signal

Abstract

An average is calculated of every predetermined number of sample amplitude values of a sound signal from an external sound source, and the respective averages are output as a time-series of average level information. On the basis of the average level information, each available section of the sound signal is detected where there appears to be a musical sound. On the basis of degrees of inclination in the average level information within the available section, stable sections are detected for detection of same-waveform sections. On the basis of the signals within the stable sections, a steady section is detected which corresponds to a note. A time-varying band-pass filtering operation is then performed on the sound signal, and detection is made of a plurality of periodic reference points of the sound signal. Subsequently, degrees of similarity in waveform are determined between every adjacent signal sections of the sound signal corresponding to the periodic reference points and those of the signal sections having a high similarity are linked together so as to detect same-waveform sections. These same-waveform sections are subdivided in consideration of level stability or the like, so as to detect a steady section representing a note. Thus, even when an input sound from a microphone or the like fluctuates slightly in pitch or level, each steady section of the sound other than the fluctuating section can be effectively analyzed.

Claims

1. A sound signal analyzing device comprising:

an input unit that inputs a sound signal to said sound signal analyzing device;

a waveform creating unit that detects a maximum value of every predetermined number of sample amplitude values of the sound signal inputted via said input unit and creates an auxiliary waveform by interpolating between the detected maximum values;

a first section detecting unit that, on the basis of the auxiliary waveform created by said waveform creating unit, detects an available section of the inputted sound signal where there appears to be a musical sound; and

a second section detecting unit that, on the basis of the sample amplitude values within said first section, detects second sections of the inputted sound signal from said first section for subsequent analysis of the sound signal.

2. A sound signal analyzing device as recited in claim 1 wherein said second section detecting unit detects said second section by:

detecting maximum values of the sample amplitude values of the inputted sound signal by performing envelope detection on the sample amplitude values in opposite directions;

interpolating between the detected maximum values to obtain a maximum-value interpolation curve;

evaluating inclinations at individual sample points on the basis of the maximum-value interpolation curve and, for each individual sample point, adding the inclination at the individual sample point with the inclinations at a plurality of other sample points to obtain a total inclination for the individual sample point; and

detecting, as a stable-level section, a signal section over some of the sample points where the total inclinations are smaller than a predetermined value and then expanding the stable-level section.

3. A sound signal analyzing device as recited in claim 1 which further comprises:

a provisional-periodic-reference-point detecting unit that detects a plurality of provisional periodic reference points of the sound signal forming said second section;

a pitch data train generating unit that detects pitches of the inputted sound signal at the provisional periodic reference points detected by said provisional-periodic-reference-point detecting unit and generates a pitch data train indicative of the detected pitches of the inputted sound signal;

a filtering unit that performs, on the inputted sound signal, a filtering operation where pass band is controlled to vary over time in accordance with frequencies corresponding to the detected pitches in the pitch data train;

a periodic-reference-point detecting unit that detects a plurality of periodic reference points of the sound signal outputted from said filtering unit;

a same-waveform-section detecting unit that determines degrees of similarity in waveform between every adjacent signal sections of the inputted sound signal corresponding to the periodic reference points detected by said periodic-reference-point detecting unit and links together those of the signal sections having a high degree of similarity to thereby detect same-waveform sections of the inputted sound signal; and

a steady section determining unit that determines a steady section of the inputted sound signal on the basis of the same-waveform sections detected by said same-waveform-section detecting unit.

4. A sound signal analyzing device as recited in claim 1 which further comprises:

a provisional-periodic-reference-point detecting unit that detects a plurality of provisional periodic reference points of the inputted sound signal forming said second section;

a pitch data train generating unit that detects pitches of the inputted sound signal at the provisional periodic reference points detected by said provisional-periodic-reference-point detecting unit and generates a pitch data train indicative of the detected pitches of the inputted sound signal;

a filtering unit that performs, on the inputted sound signal, a filtering operation where pass band is controlled to vary over time in accordance with frequencies corresponding to the detected pitches in the pitch data train;

a periodic-reference-point detecting unit that detects a plurality of periodic reference points of the sound signal outputted from said filtering unit;

a voiced-sound-containing section detecting unit that determines degrees of similarity in waveform between every adjacent signal sections of the inputted sound signal corresponding to the periodic reference points detected by said periodic-reference-point detecting unit and detects a voiced-sound-containing section of the inputted sound signal on the basis of the degree of similarity; and

a steady section determining unit that sequentially calculates degrees of similarity in waveform between a high-similarity basic signal section within the voiced-sound-containing section and other signal sections located to opposite sides of the basic signal section and determines a steady section of the inputted sound signal on the basis of the degrees of similarity.

5. A sound signal analyzing device as recited in claim 1 which further comprises a note analyzing unit that analyzes a representative frequency of the inputted sound signal in said second section detected by said second section detecting unit and thereby determines a note of the inputted sound signal.

6. A sound signal analyzing device comprising:

an input unit that inputs a sound signal to said sound signal analyzing device;

an arithmetic operating unit that calculates an average of every predetermined number of sample amplitude values of the sound signal inputted via said input unit and outputs respective said averages as a time-series of average level information;

a first section detecting unit that, on the basis of the average level information outputted from said arithmetic operating unit, detects a first section of the inputted sound signal where there appears to be a musical sound; and

a second section detecting unit that, on the basis of the sample amplitude values within said first section, detects second sections of the inputted sound signal from said first section for subsequent analysis of the sound signal.

7. A sound signal analyzing device as recited in claim 6 which further comprises a note analyzing unit that analyzes a representative frequency of the inputted sound signal in said second section detected by said second section detecting unit and thereby determines a note of the inputted sound signal.

8. A sound signal analyzing device comprising:

an input unit that inputs a sound signal to said sound signal analyzing device;

a first pitch detecting unit that detects a pitch of the sound signal, inputted via said input unit, for every predetermined signal section and generates a pitch data train indicative of the detected pitches of the inputted sound signal;

a filtering unit that performs, on the inputted sound signal, a filtering operation where pass band is controlled to vary over time in accordance with frequencies corresponding to the detected pitches in the pitch data train; and

a determining unit that determines degrees of similarity in waveform between every adjacent signal sections on the basis of successive sample amplitude values of the inputted sound signal having undergone the filtering operation;

a section detecting unit that detects, as same-waveform sections, those of the signal sections having waveforms determined by said determining unit as being similar within a range corresponding to a predetermined condition; and

a second pitch detecting unit that detects a pitch of the sound signal within the same-waveform sections detected by said section detecting unit.

9. A sound signal analyzing device as recited in claim 8 wherein said first pitch detecting unit includes:

a provisional-periodic-reference-point detecting unit that detects a plurality of provisional periodic reference points of the sound signal inputted via said input unit; and

a pitch data train generating unit that detects pitches of the inputted sound signal at the provisional periodic reference points detected by said provisional-periodic-reference-point detecting unit and generates a pitch data train indicative of the detected pitches of the inputted sound signal, said pitch data train generating unit interpolating between pitch data of the inputted sound signal determined at individual ones of the provisional periodic reference points, so as to detect the pitches and generate a data train of the detected pitches of the inputted sound signal.

10. A sound signal analyzing device as recited in claim 8 wherein said first pitch detecting unit includes:

a provisional-periodic-reference-point detecting unit that detects a plurality of provisional periodic reference points of the sound signal inputted via said input unit; and

a pitch data train generating unit that detects pitches of the inputted sound signal at the provisional periodic reference points detected by said provisional-periodic-reference-point detecting unit and generates a pitch data train indicative of the detected pitches of the inputted sound signal, and wherein said provisional-periodic-reference-point detecting unit detects, as the provisional periodic reference points, peak points of the inputted sound signal by focusing on one of plus and minus amplitude sides of a waveform of the inputted sound signal where stronger peaks appear than on another of the plus and minus amplitude sides.

11. A sound signal analyzing device as recited in claim 8 wherein said first pitch detecting unit includes:

a periodic-reference-point detecting unit that detects a plurality of periodic reference points of the sound signal inputted via said input unit; and

a pitch data train generating unit that detects pitches of the inputted sound signal at the periodic reference points detected by said periodic-reference-point detecting unit and generates a pitch data train indicative of the detected pitches of the inputted sound signal, and

wherein said periodic-reference-point detecting unit detects, as the periodic reference points, peak points of the inputted sound signal by focusing on one of plus and minus amplitude sides of a waveform of the inputted sound signal where stronger peaks appear than on another of the plus and minus amplitude sides.

12. A sound signal analyzing device as recited in claim 8 wherein said first pitch detecting unit includes:

a provisional-periodic-reference-point detecting unit that detects a plurality of provisional periodic reference points of the sound signal inputted via said input unit; and

a pitch data train generating unit that detects pitches of the inputted sound signal at the provisional periodic reference points detected by said provisional-periodic-reference-point detecting unit and generates a pitch data train indicative of the detected pitches of the inputted sound signal, and

wherein said provisional-periodic-reference-point detecting unit divides a waveform of the inputted sound signal into signal sections at predetermined intervals corresponding to the cutoff frequency used in the filtering operation, by focusing on one of plus and minus amplitude sides of a waveform of the inputted sound signal, having undergone the filtering operation, where stronger peaks appear than on another of the plus and minus amplitude sides, and said provisional-periodic-reference-point detecting unit detects a greatest peak within each of the signal sections as the periodic reference point.

14. A sound signal analyzing device as recited in claim 8 which further comprises a note analyzing unit that analyzes a representative frequency of the inputted sound signal in the section detected by said section detecting unit and thereby determines a note of the inputted sound signal.

13. A sound signal analyzing device comprising;

an input unit that inputs a sound signal to said sound signal analyzing device;

a first filtering unit that performs, on the sound signal inputted via said input unit, a band-pass filtering operation using predetermined cut-off frequencies as maximum and minimum frequencies;

a first periodic-reference-point detecting unit that detects a plurality of provisional periodic reference points of the sound signal outputted from said first filtering unit;

a frequency range detecting unit that detects the maximum and minimum frequencies of the inputted sound signal on the basis of the provisional periodic reference points detected by said first periodic-reference-point detecting unit;

a second filtering unit that performs, on the sound signal inputted via said input unit, a band-pass filtering operation using as cut-off frequencies the maximum and minimum frequencies detected by said frequency range detecting unit;

a second periodic-reference-point detecting unit that detects a plurality of periodic reference points of the sound signal outputted from said second filtering unit; and

a pitch detecting unit that detects a pitch of the sound signal for each of said periodic reference points detected by said second periodic-reference-point detecting unit.

15. A sound signal analyzing device comprising:

an input unit that inputs a sound signal to said sound signal analyzing device;

a first pitch detecting unit that detects a pitch of the sound signal, inputted via said input unit, for every predetermined signal section and generates a pitch data train indicative of the detected pitches of the inputted sound signal;

a filtering unit that performs, on the inputted sound signal, a filtering operation where pass band is controlled to vary over time in accordance with frequencies corresponding to the detected pitches in the pitch data train; and

a second pitch detecting unit that detects pitches of the inputted sound signal on the basis of sample amplitude values of the sound signal outputted from said filtering unit.

16. A sound signal analyzing device comprising:

an input unit that inputs a sound signal to said sound signal analyzing device;

a filtering unit that performs, on the sound signal inputted via said input unit, a filtering operation using a predetermined frequency range;

a determining unit that determines degrees of similarity in waveform between every adjacent signal sections on the basis of successive sample amplitude values of the inputted sound signal having undergone the filtering operation;

a section detecting unit that detects, as same-waveform sections, those of the signal sections having waveforms determined by said determining unit as being similar within a range corresponding to a predetermined condition; and

a pitch detecting unit that detects a pitch of the sound signal within the same-waveform sections detected by said same-waveform-section detecting unit.

17. A sound signal analyzing device comprising:

an input unit that inputs a sound signal to said sound signal analyzing device;

pitch detecting unit that detects a pitch of the sound signal, inputted via said input unit, for every predetermined signal section and generates a pitch data train indicative of the detected pitches of the inputted sound signal;

a filtering unit that performs, on the inputted sound signal, a filtering operation where pass band is controlled to vary over time in accordance with frequencies corresponding to the detected pitches in the pitch data train;

a periodic-reference-point detecting unit that detects a plurality of periodic reference points of the sound signal outputted from said filtering unit;

a voiced-sound-containing section detecting unit that determines degrees of similarity in waveform between every adjacent signal sections of the inputted sound signal corresponding to the periodic reference points detected by said periodic-reference-point detecting unit and detects a voiced-sound-containing section of the inputted sound signal on the basis of the degree of similarity; and

a steady section determining unit that sequentially calculates degrees of similarity in waveform between a high-similarity basic signal section within the voiced-sound-containing section and other signal sections located to opposite sides of the basic signal section and determines a steady section of the inputted sound signal on the basis of the degrees of similarity.

18. A sound signal analyzing device as recited in claim 17 which further comprises a note analyzing unit that analyzes a representative frequency of the inputted sound signal in the steady section determined by said steady section determining unit and thereby determines a note of the inputted sound signal.

19. A sound signal analyzing device comprising:

an input unit that inputs a sound signal to said sound signal analyzing device;

a stable section analyzing unit that determines a stable section of the sound signal, inputted via said input unit, for subsequent analysis of the sound signal;

pitch detecting unit that detects a pitch of the inputted sound signal forming the stable section and generates a pitch data train indicative of the detected pitches of the inputted sound signal;

a filtering unit that performs, on the inputted sound signal, a filtering operation where pass band is controlled to vary over time in accordance with frequencies corresponding to the detected pitches in the pitch data train;

a periodic-reference-point detecting unit that detects a plurality of periodic reference points of the sound signal outputted from said filtering unit;

a voiced-sound-containing section detecting unit that determines degrees of similarity in waveform between every adjacent signal sections of the inputted sound signal corresponding to the periodic reference points detected by said periodic-reference-point detecting unit and detects a voiced-sound-containing section of the inputted sound signal on the basis of the degree of similarity; and

a steady section determining unit that sequentially calculates degrees of similarity in waveform between a high-similarity basic signal section within the voiced-sound-containing section and other signal sections located to opposite sides of the basic signal section and determines a steady section of the inputted sound signal on the basis of the degrees of similarity.

20. A sound signal analyzing device comprising:

an input unit that inputs a sound signal to said sound signal analyzing device;

a filtering unit that performs, on the sound signal inputted via said input unit, a filtering operation using a predetermined bass band;

a peak point detecting unit that detects peak points in the inputted sound signal having undergone the filtering operation by said filtering unit;

a same-waveform-section detecting unit that, of signal sections obtained by dividing a waveform of the inputted sound signal at optional pairs of the peak points detected by said peak point detecting unit, selects as many pairs of adjacent signal sections as possible that meet a limit defined by the pass band of said filtering unit, said same-waveform-section detecting unit determining a degree of similarity in waveform between two signal sections in each of the selected pairs and detecting one of the selected pairs having a highest similarity as same-waveform sections; and

a steady section determining unit that determines a steady section of the inputted sound signal on the basis of the same-waveform sections detected by said same-waveform section detecting unit.

21. A sound signal analyzing device as recited in claim 20 which further comprises a note analyzing unit that analyzes a representative frequency of the inputted sound signal in the steady section determined by said steady section determining unit and thereby determines a note of the inputted sound signal.

22. A sound signal analyzing device comprising:

an input unit that inputs a sound signal to said sound signal analyzing device;

a peak point detecting unit that detects peak points in the sound signal inputted via said input unit;

a first same-waveform-section detecting unit that, of signal sections obtained by dividing a waveform of the inputted sound signal at optional pairs of the peak points detected by said peak point detecting unit, determines degrees of similarity in waveform between every two said signal sections and links together those of the signal sections having a high similarity so as to detect a first same-waveform section group;

a second same-waveform-section detecting unit that, using leading and last signal sections in said first same-waveform section group as a basis of comparison, calculates degrees of similarity in waveform between said first same-waveform section group and other signal sections adjoining said leading and last signal sections and expands said first same-waveform section group to incorporate one or more of the other signal sections depending on the calculated degrees of similarity, said second same-waveform-section detecting unit detecting the expanded first same-waveform section group as a second same-waveform section group; and

a steady section determining unit that determines a steady section of the inputted sound signal on the basis of said second same-waveform section group detected by said second same-waveform-section detecting unit.

23. A sound signal analyzing device as recited in claim 22 wherein if there is any gap signal section that does not belong to either of adjacent said second same-waveform sections, degrees of similarity in waveform are evaluated between said last signal section of a preceding one of said adjacent second same-waveform sections and the gap signal section and between said leading signal section of a succeeding one of said adjacent second same-waveform sections and the gap signal section, and the gap signal section is incorporated into one of said adjacent second same-waveform sections to which the gap signal section has a higher degrees of similarity in waveform.

24. A sound signal analyzing device as recited in claim 22 which further comprises a note analyzing unit that analyzes a representative frequency of the inputted sound signal in the steady section determined by said steady section determining unit and thereby determines a note of the inputted sound signal.

25. A sound signal analyzing device comprising:

an input unit that inputs a sound signal to said sound signal analyzing device;

pitch detecting unit that detects a pitch of the sound signal, inputted via said input unit, for every predetermined signal section and generates a pitch data train indicative of the detected pitches of the inputted sound signal;

a first filtering unit that performs, on the inputted sound signal, a filtering operation where pass band is controlled to vary over time in accordance with frequencies corresponding to the detected pitches in the pitch data train;

a periodic-reference-point detecting unit that detects a plurality of periodic reference points of the sound signal outputted from said first filtering unit;

a second filtering unit that performs, on the inputted sound signal, a filtering operation where pass band or bands is controlled to vary over time in accordance with frequencies corresponding to the detected pitches in the pitch data train and integer multiples of the frequencies;

a same-waveform-section detecting unit that determines degrees of similarity in waveform between every adjacent signal sections obtained by dividing the sound signal waveform outputted from said second filtering unit and links together those of the signal sections having a high similarity so as to detect same-waveform sections of the inputted sound signal; and

a steady section determining unit that determines a steady section of the inputted sound signal on the basis of the same-waveform sections detected by said same-waveform-section detecting unit.

26. A sound signal analyzing device as recited in claim 25 which further comprises a note analyzing unit that analyzes a representative frequency of the inputted sound signal in the steady section determined by said steady section determining unit and thereby determines a note of the inputted sound signal.

27. A sound signal analyzing device comprising:

a supplying unit that supplies successive sample amplitude values of a sound signal;

a first filtering unit that performs, on the successive sample amplitude values supplied by said supplying unit, a first filtering operation in accordance with a predetermined frequency characteristic;

a control data creating unit that create control frequency data for a second filtering operation on the basis of the successive sample amplitude values having undergone said first filtering operation;

a second filtering unit that performs, on the supplied successive sample amplitude values, a second filtering operation in accordance with a frequency characteristic based on the control frequency data created by said control data creating unit; and

a pitch detecting unit that detect a pitch of the sound signal on the basis of the successive sample amplitude values having undergone said second filtering operation.

28. A sound signal analyzing device comprising:

an input unit that inputs a sound signal to said sound signal analyzing device;

pitch detecting unit that detects a pitch of the sound signal, inputted via said input unit, for every predetermined signal section and generates a pitch data train indicative of the detected pitches of the inputted sound signal;

a converting unit that converts differences between every adjacent ones of the pitches in the pitch data train into respective relative values based on musical interval representation in cents;

a dynamic reference calculating unit that calculates dynamic reference values on the basis of dynamic averages of the relative values obtained by said converting unit; and

a steady section determining unit that detects a stable-pitch steady section by comparing the relative values and the dynamic reference values calculated by said dynamic reference calculating unit.

29. A sound signal analyzing device as recited in claim 28 wherein said dynamic reference calculating unit calculates the dynamic reference values using any one of a value obtained by multiplying the dynamic averages of the relative values by a predetermined value, a value obtained by adding the predetermined value to the dynamic averages of the relative values and a value obtained by adding the predetermined value to said value obtained by multiplying the dynamic averages of the relative values by the predetermined value.

30. A sound signal analyzing device as recited in claim 28 which further comprises a note analyzing unit that analyzes a representative frequency of the inputted sound signal in the steady section determined by said steady section determining unit and thereby determines a note of the inputted sound signal.

31. A sound signal analyzing device comprising:

an input unit that inputs to said sound signal analyzing device a sound signal comprising a time series of one or more notes;

a section detecting unit that detects, from the sound signal inputted via said input unit, signal sections appearing to correspond to a single note; and

a unit that arranges the signal sections, detected by said section determining unit, on grids divided at time intervals corresponding to a predetermined note length in order of a time series thereof, said unit allotting each of the signal sections to one of the grids nearest to a start point thereof, and wherein if a plurality of the signal sections are simultaneously allotted to a particular one of the grids, one of the signal sections having a greatest time length is selected as valid.

32. A sound signal analyzing device comprising:

an input unit that inputs a sound signal to said sound signal analyzing device;

pitch detecting unit that detects a pitch of the sound signal, inputted via said input unit, for every predetermined signal section and generates a pitch data train indicative of the detected pitches of the inputted sound signal;

a converting unit that converts differences between every adjacent ones of the pitches in the pitch data train into respective relative values based on musical interval representation in cents;

a dynamic reference calculating unit that calculates dynamic reference values on the basis of dynamic averages of the relative values obtained by said converting unit;

a steady section determining unit that detects a stable-pitch steady section by comparing the relative values and the dynamic reference values calculated by said dynamic reference calculating unit;

a static reference calculating unit that calculates a static reference on the basis of a static average of the relative values within the steady section detected by said steady section determining unit;

a pitch-determining-section detecting unit that compares the static reference and the relative values within the steady section so as to detect a pitch determining section for calculating a representative frequency of the steady section; and

a frequency calculating unit that calculates the representative frequency of the steady section on the basis of a pitch data train within the pitch determining section detected by said pitch-determining-section detecting unit.

33. A sound signal analyzing device as recited in claim 32 which further comprises a note analyzing unit that analyzes a representative frequency of the inputted sound signal in the steady section determined by said steady section determining unit and thereby determines a note of the inputted sound signal.

34. A performance information generating device comprising:

an input unit that inputs an optional sound signal to said performance information generating device;

a section analyzing unit that analyzes a signal section, of the sound signal inputted via said input unit, corresponding to a single note;

a frequency range determining unit that determines a representative frequency of each said signal section analyzed by said section analyzing unit;

a converting unit that converts a difference, in the representative frequency between a predetermined one of the analyzed signal section and every other said analyzed signal section, into a relative value based on musical interval representation in cents; and

a note assigning unit that assigns respective notes of a predetermined scale to the analyzed signal sections on the basis of the corresponding musical interval data.

35. A sound signal analyzing device comprising:

an input unit that inputs a sound signal to said sound signal analyzing device;

an arithmetic operating unit that calculates an average of every predetermined number of sample amplitude values of the sound signal inputted via said input unit and outputs respective said averages as a time-series of average level information;

a section determining unit that determines each signal section of the inputted sound signal in which the average level calculated by said arithmetic operating unit is greater than a first predetermined value as an available section where there appears to be a musical sound, and determines each other signal section of the inputted sound signal where the average level calculated by said arithmetic operating unit is smaller than said first predetermined value as an unavailable section where there appears to be no musical sound;

an available section adding unit that if any particular one of the unavailable sections located between the available sections is of a time length smaller than a first predetermined length, changes the particular unavailable section into an additional available section and combines the additional available section and said available sections adjoining opposite sides of the additional available section, said available section adding unit determining a combination of the additional available section and adjoining available sections as a new available section;

a first unavailable section adding unit that if any particular one of the available sections located between the unavailable sections is of a time length smaller than a second predetermined length after determination by said available section adding unit, changes the particular available section into an additional unavailable section and combines the additional unavailable section and said unavailable sections adjoining opposite sides of the additional unavailable section, said first unavailable section adding unit determining a combination of the additional unavailable section and adjoining unavailable sections as a new unavailable section; and

a second unavailable section adding unit that calculates an average of the average levels in each of the available sections after determination by said first unavailable section adding unit and that if the calculated average of any particular one of the available sections is smaller than a second predetermined value, changes the particular available section into an additional unavailable section.

36. A sound signal analyzing device comprising:

an input unit that inputs a sound signal to said sound signal analyzing device;

an arithmetic operating unit that calculates an average of every predetermined number of sample amplitude values of the sound signal inputted via said input unit and outputs respective said averages as a time-series of average level information;

a section determining unit that determines each signal section of the inputted sound signal where the average level calculated by said arithmetic operating unit is greater than a first predetermined value as an available section, determines each signal section of the inputted sound signal which is located between the available sections and where the average level calculated by said arithmetic operating unit is smaller than said first predetermined value as an unavailable section, and also determines each other signal section than the available and unavailable sections as an undetermined section;

an available section adding unit that if any particular one of the unavailable sections located between the available sections is of a time length smaller than a first predetermined length, changes the particular unavailable section into an additional available section and combines the additional available section and said available sections adjoining opposite sides of the additional available section, said available section adding unit determining a combination of the additional available section and adjoining available sections as a new available section;

a first unavailable section adding unit that if any particular one of the available sections located between the unavailable sections is of a time length smaller than a second predetermined length after determination by said available section adding unit, changes the particular available section into an additional unavailable section and combines the additional unavailable section and said unavailable sections adjoining opposite sides of the additional unavailable section so that said first unavailable section adding unit determines a combination of the additional unavailable section and adjoining unavailable sections as a new unavailable section, and that if any particular one of the available sections adjoining the undetermined section is of a time length smaller than said second predetermined length after determination by said available section adding unit, combines the particular available section and the unavailable and undetermined sections adjoining the particular available section so that said first unavailable section adding unit determines a combination of the particular available section and the unavailable and undetermined sections adjoining the particular available section as a new undetermined section; and

a second unavailable section adding unit that calculates an average of the average levels in each of the available and undetermined sections after determination by said first unavailable section adding unit and that if the calculated average of any particular one of the available and undetermined sections is smaller than a second predetermined value, changes the particular available or undetermined section into an additional unavailable section, but, if the calculated average of any particular one of the available and undetermined sections is greater than said second predetermined value, changes the undetermined section into an additional available section.

37. A sound signal analyzing device comprising:

an input unit that inputs a sound signal to said sound signal analyzing device;

a periodic-reference-point detecting unit that detects a plurality of periodic reference points of the sound signal inputted via said input unit;

a same-waveform-section detecting unit that determines degrees of similarity in waveform between every adjacent signal sections of the inputted sound signal corresponding to the periodic reference points detected by said periodic-reference-point detecting unit and links together the signal sections having a high similarity so as to detect same-waveform sections; and

a steady section determining unit that determines a steady section of the inputted sound signal on the basis of the same-waveform sections detected by said same-waveform section detecting unit.

38. A sound signal analyzing device as recited in claim 37 which further comprises a note analyzing unit that analyzes a representative frequency of the inputted sound signal in the steady section determined by said steady section determining unit and thereby determines a note of the inputted sound signal.

39. A sound signal analyzing device comprising:

an input unit that inputs a sound signal to said sound signal analyzing device;

a first periodic-reference-point detecting unit that detects a plurality of provisional periodic reference points of the sound signal inputted via said input unit;

a frequency range detecting unit that detects maximum, and minimum frequencies of the inputted sound signal on the basis of the provisional periodic reference points detected by said first periodic-reference-point detecting unit;

a filtering unit that performs, on the inputted sound signal, a band-pass filtering operation using as a cut-off frequency the maximum and minimum frequencies detected by said frequency range detecting unit;

a second periodic-reference-point detecting unit that detects a plurality of periodic reference points of the sound signal outputted from said filtering unit;

a same-waveform-section detecting unit that determines degrees of similarity in waveform between every adjacent one of signal sections of the inputted sound signal corresponding to the periodic reference points detected by said second periodic-reference-point detecting unit and links together the signal sections having a high similarity so as to detect same-waveform sections; and

a steady section determining unit that determines a steady section of the inputted sound signal on the basis of the same-waveform sections detected by said same-waveform-section detecting unit.

40. A sound signal analyzing device comprising:

an input unit that inputs a sound signal to said sound signal analyzing device;

an available section analyzing unit that determines an available section of the sound signal, inputted via said input unit, where there appears to be a musical sound;

a periodic-reference-point detecting unit that detects a plurality of periodic reference points on plus and minus amplitude sides of the inputted sound signal forming the available section;

a same-waveform-section detecting unit that for each of the plus and minus amplitude sides of the inputted sound signal, determines degrees of similarity in waveform between every adjacent signal sections of the inputted sound signal corresponding to the periodic reference points detected by said periodic-reference-point detecting unit and links together the signal sections having a high similarity so as to detect same-waveform sections;

a tone-color-section determining unit that determines, as same-tone-color sections, signal sections obtained by superposing the plus and minus amplitude sides of the same-waveform sections detected by said same-waveform-section detecting unit; and

a steady section determining unit that determines a steady section of the inputted sound signal on the basis of the same-tone-color sections determined by said tone-color-section determining unit.

41. A sound signal analyzing device comprising:

an input unit that inputs a sound signal to said sound signal analyzing device;

an available section analyzing unit that determines an available section of the sound signal, inputted via said input unit, where there appears to be a musical sound;

a first periodic-reference-point detecting unit that detects a plurality of provisional periodic reference points of the inputted sound signal forming the available section;

a frequency range detecting unit that detects maximum and minimum frequencies of the inputted sound signal on the basis of the provisional periodic reference points detected by said first periodic-reference-point detecting unit;

a filtering unit that performs, on the inputted sound signal, a band-pass filtering operation using as a cut-off frequency the maximum and minimum frequencies detected by said frequency range detecting unit;

a second periodic-reference-point detecting unit that detects a plurality of periodic reference points of the sound signal outputted from said filtering unit;

a same-waveform-section detecting unit that, for each of plus and minus amplitude sides of the inputted sound signal, determines degrees of similarity in waveform between every adjacent one of signal sections of the inputted sound signal corresponding to the periodic reference points detected by said second periodic-reference-point detecting unit and links together the signal sections having a high similarity so as to detect same-waveform sections; and

a steady section determining unit that determines a steady section of the inputted sound signal on the basis of the same-waveform sections detected by said same-waveform-section detecting unit.

42. A performance information generating device comprising:

an input unit that inputs an optional sound signal to said performance information generating device;

a steady section analyzing unit that analyzes a steady section, of the sound signal inputted via said input unit, corresponding to a single note;

a frequency range determining unit that determines a representative frequency of each said steady section analyzed by said steady section analyzing unit;

a converting unit that converts differences in the representative frequency between every adjacent ones of said steady sections into relative values based on musical interval representation in cents;

a musical interval data creating unit that creates musical interval data indicative of a musical interval between the adjacent steady sections on the basis of the corresponding relative value; and

a note assigning unit that assigns respective notes of a predetermined scale to the steady sections on the basis of the corresponding musical interval data.

43. A performance information generating device comprising:

an input unit that inputs an optional sound signal to said performance information generating device;

a steady section analyzing unit that analyzes a steady section, of the sound signal inputted via said input unit, corresponding to a single note;

a frequency range determining unit that determines a representative frequency of each said steady section analyzed by said steady section analyzing unit;

a phrase detecting unit that combines a plurality of the steady sections analyzed by said steady section analyzing unit to detect a single phrase;

a converting unit that converts a difference in the representative frequency between each of the steady sections within the phrase detected by said phrase detecting unit and every other steady section preceding said steady sections within the phrase, into a relative value based on musical interval representation in cents;

a weighing unit that, for each of the steady sections within the phrase detected by said phrase detecting unit, calculates a weight based on a time distance relative to every other said steady section preceding said steady section;

a musical interval data calculating unit that, for each of the steady sections, calculates musical interval data indicative of a musical interval from another said steady section on the basis of the corresponding relative value obtained by said converting unit and the corresponding weight calculated by said weighing unit; and

a note assigning unit that assigns respective notes of a predetermined scale to the steady sections on the basis of the corresponding musical interval data.

44. A performance information generating device comprising:

an input unit that inputs an optional sound signal to said performance information generating device;

a steady section analyzing unit that analyzes a steady section, of the sound signal inputted via said input unit, corresponding to a single note;

a frequency range determining unit that determines a representative frequency of each said steady section analyzed by said steady section analyzing unit;

a phrase detecting unit that combines a plurality of the steady sections analyzed by said steady section analyzing unit to detect a single phrase;

a converting unit that converts a difference in the representative frequency between a leading one of the steady sections within the phrase detected by said phrase detecting unit and every other said steady section succeeding said leading steady section, into a relative value based on musical interval representation in cents;

a musical interval data calculating unit that, for each of the steady sections, calculates musical interval data dicative of a musical interval from said leading steady section on the basis of the corresponding relative value obtained by said converting unit; and

a note assigning unit that assigns respective of a predetermined scale to the steady sections on the basis of the corresponding musical interval data.

45. A performance information generating device comprising:

an input unit that inputs an optional sound signal to said performance information generating device;

a steady section analyzing unit that analyzes a steady section, of the sound signal inputted via said input unit, corresponding to a single note; and

a note assigning unit that analyzes a representative frequency of the sound signal for each said steady section analyzed by said steady section analyzing unit and assigns respective notes of a predetermined scale to the steady sections on the basis of analyzed results, said note assigning unit first assigning a predetermined note of the predetermined scale to a leading one of the steady sections and then sequentially assigning a note of the predetermined scale to every other said steady section.

46. A performance information generating device comprising:

an input unit that inputs an optional sound signal to said performance information generating device;

a steady section analyzing unit that analyzes a steady section, of the sound signal inputted via said input unit, corresponding to a single note; and

a note assigning unit that analyzes a representative frequency of the sound signal for each said steady section analyzed by said steady section analyzing unit and assigns respective notes of a predetermined scale to the steady sections on the basis of analyzed results, wherein said note assigning unit first analyzes a leading one of the steady sections to detect an average frequency of the leading steady section and assigns a predetermined note, based on the detected average frequency, of the predetermined scale to the leading steady section and then sequentially assigning a note of the predetermined scale to every other said steady section.

47. A performance information generating device comprising:

an input unit that inputs an optional sound signal to said performance information generating device;

a steady section analyzing unit that analyzes a steady section, of the sound signal inputted via said input unit, corresponding to a single note; and

a note assigning unit that analyzes a representative frequency of the sound signal for each said steady section analyzed by said steady section analyzing unit and assigns respective notes of a predetermined scale to the steady sections on the basis of analyzed results, wherein said note assigning unit first provisionally assigns respective notes of a plurality of scales to the steady sections while deviating note positions from each other so as to calculate cumulative total note assignment differences at the individual note positions of the scales and then determines an optimum scale on the basis of the calculated cumulative total note assignment differences so as to sequentially assign respective notes of the determined optimum scale to the steady sections.

48. A performance information generating device comprising:

an input unit that inputs an optional sound signal to said performance information generating device;

a steady section analyzing unit that analyzes a steady section, of the sound signal inputted via said input unit, corresponding to a single note; and

a note assigning unit that analyzes a representative frequency of the sound signal for each said steady section analyzed by said steady section analyzing unit and selects a predetermined scale on the basis of analyzed results so as to assigns respective notes of the predetermined scale to the steady sections, wherein in assigning the respective notes of the predetermined scale, said note assigning unit being capable of assigning a note, other than the notes of the predetermined scale, depending on a predetermined note difference allowance.