JPH0310052B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a musical note display device, and an object of the present invention is to provide a musical note display device that can accurately display notes with easy-to-read note values by varying the frequency analysis period even when input at the same tempo. shall be.

The applicant previously filed Japanese Patent Application No. 57-232457 (Japanese Unexamined Patent Publication No.
59-124384) and Japanese Patent Application No. 58-3670 (Japanese Unexamined Patent Publication No. 59-128576) "Musical note display device" converts the input audio signal into a digital signal, analyzes the frequency of this, and determines the pitch. Determine the pitch of the sound and display it on the CRT
proposed a device that displays music notation in real time.
This method performs an FFT operation on audio signal data converted to a digital signal, then calculates the result into a power spectrum to obtain a spectral value, then calculates the maximum value among these spectral values, and calculates the maximum value. Find the frequency value of the spectrum that has the lowest frequency among the spectra that have a frequency lower than the spectral frequency that indicates the frequency and that has a smaller spectrum within a predetermined range than the maximum spectrum, and use it as the pitch of the input audio signal. judge,
On the other hand, when there is no spectrum that satisfies the above conditions, the frequency value indicating the maximum spectrum is determined to be the pitch of the input audio signal, and this determination result is processed by a video display processor (hereinafter referred to as
Video RAM (hereinafter referred to as VDP)
(VRAM) and display it on a CRT.

However, this method only displays the pitch of the input audio signal, but cannot display the length of the sound. Therefore, it would be easier to see and more convenient if both the pitch and length of the input audio signal were analyzed and displayed as actual notes on the musical staff in real time.

The present invention satisfies the above requirements, and one embodiment thereof will be described below with reference to the drawings.

FIG. 1 shows a block system diagram of an embodiment of a musical note display device according to the present invention. In the same figure, terminal 1
The incoming input audio signal is supplied to a graphic equalizer 2, where it is varied to have frequency characteristics that are easy to analyze, and then passed through an anti-aliasing filter 3.
At the same time, unnecessary high frequency components are removed so as not to cause aliasing noise, and the signals are also supplied to the AD converter 4. Initial settings (system initialization) are performed in the control device 5 (step 19 in FIG. 2A), and each operation of the steps shown in FIG. 2A is executed as long as no interrupt occurs.

In the initial settings, for example, a standard speed of ♪ = 60 is set, and the periodic data RAM corresponding to this speed is set.
7 cycle/wait areas are preset. The periodic data in this area is configured to be able to be rewritten as appropriate as described later. On the other hand, in this embodiment, if you do not want to display the current value of the note due to the above-mentioned standard speed, you can change the display to the desired current value. 15 and a non-locking cycle indicator switch 16 for setting a desired market price.

For example, if you want to display the market price as it is at standard speed, do not operate switches 15 and 16, but just step
20 to step 21. When an interrupt occurs every sampling period of the AD converter 4 (step 45 in FIG. 2B), the operation shown in FIG.
AD conversion is performed in the AD converter 4 (step 46), and the digital signals are sequentially stored in the AD conversion data area shown in FIG. 3 of the RAM 7 (step 47). In this case, the pointer indicates the delimitation of a series of data (step 48), and if the pointer has not reached all addresses, the process returns.

In this way, a predetermined number of digital data is
Once stored in RAM 7, calculation and pitch analysis section 8
FFT calculation is performed at (step 21)
The calculation result is stored in the RAM 7, and then a power spectrum calculation is performed (step 22) and the calculation result is stored in the RAM 7. The maximum spectral value is then determined, and then a spectral value that exists in a frequency region lower than the frequency of the spectrum exhibiting the maximum spectral value and is smaller within a predetermined range than the spectral size of the maximum spectral value is determined. The frequency value of the spectrum that shows the lowest frequency value among the spectra that it has is determined to be the pitch (fundamental tone) of the input audio signal, and if there is no spectrum that meets the above conditions, The frequency value of the spectrum indicating the maximum spectrum value is determined to be the pitch (fundamental tone) of the input audio signal and is stored in the RAM 7.

The time required for the operations in steps 21 to 23 above is the fourth
The time is set in advance to correspond to the display of an eighth note shown in FIG. A, and in steps 21 to 23, the pitch of the input audio signal at time t1 shown in FIG. ₅ is analyzed.

Suppose now that the G and A notes of the eighth note shown in FIG. 6 are repeatedly input using a musical instrument such as a piano, which attenuates over time. At time _t1 , when the pitch analysis in steps 21 to 23 is performed, the analysis number detection and pattern data detection section 1
A pattern data command signal is extracted from 0 and supplied to the pattern data determining section 11, where pattern data is created based on the pitch analyzed by the analyzing section 8 (step 24).

Here, the relationship between the count number and the note length, which will be described later, is as shown in FIGS. 4A to 4I, from eighth notes to whole notes, corresponding to count numbers 0 to 8, respectively.
In this case, since the count number is zero and the pitch is G, pattern data corresponding to the G note of an eighth note is extracted and sent to the VRAM1 via the VDP12.
3 and written into a predetermined table.

As shown in FIG. 7, the memory map of the VRAM 13 includes a sprite generator table SGT and a pattern generator table PGT that store multiple types of patterns, and a display screen (32 columns x 24 rows) on the CRT 14 shown in FIG. ), each pattern has a capacity corresponding to each section PNT,
It is composed of a sprite attribute table SAT that stores information about the vertical position and horizontal position of the display surface, a color table CT that stores color information, and an unused table. VDP1
In 2, the pattern name table of VRAM13
In accordance with the data written in the PNT and the sprite attribute table SAT, a pattern to be displayed on the display screen of the CRT 14 is selected and the movement mode of the pattern is specified, and a composite video signal is created.
The signal is supplied to the CTR 14, and pattern a (eighth note G note) is displayed on the display screen here (step 25).
Note that the staff score, clef, etc. are displayed in advance using data stored in the RAM 7 in advance.

When pattern a is displayed, step 26
The process waits for a time period corresponding to the standard cycle/weight data (corresponding to ♪=60 in this case) initialized in the RAM 7 to proceed to the next step 27 (FFT calculation). After this time has elapsed, the fifth
At time _t2 shown in the figure, the pitch analysis of the A sound is performed in steps 27 to 29, and then the continuous sound detection section 9 judges whether or not it is a continuous sound (steps 27 to 29).
30). Here, the results of the previous pitch analysis (time t ₁ ) and the results of the current pitch analysis (time t ₂ ) are compared, and it is determined whether the pitches of the two are the same or not, and the levels of the two are determined. It is determined whether the difference is within a preset level difference range, and it is also determined whether the result of the current pitch analysis is above a preset threshold level L (Figure 5). be done.

In this case, the continuous sound detecting section 9 detects it as a discontinuous sound, and in steps 34 and 35, the eighth note A note at time _t2 is displayed (pattern b), and in step 26
Weighting is performed by steps 27 to 29 again.
Pitch analysis at time t ₃ is performed.

Next, when a quarter note C note is input as shown in pattern c in Figure 6, since the count is zero, the C note is displayed in the form of an eighth note in step 29 (Figure 4A). , continuous sound is determined in step 30, the count number is set to 1 in step 31, step 32,
33, the C note is redisplayed in the form of a quarter note in accordance with the count number 1 (Figure 4B). Next, in steps 27 to 29, the pitch of the next input note after the C note of this quarter note is determined, and if a discontinuous note is determined in step 30, the pitch of the next input note is determined in step 30. 34 and 35 are displayed as eighth notes. Thereafter, a count is cleared in step 36, a wait is performed in step 26, and a pitch analysis of the next note is performed again in steps 27 to 29.

In this way, in steps 25 and 35, the pitch of the note to be displayed is displayed in the form of an eighth note, and in step 33, the stem etc. of the note passing in the middle is displayed, and the note is rewritten. The final pattern of power notes is displayed. As shown in Fig. 4 A to I,
Patterns for half notes and dotted half notes are also displayed according to the corresponding count number, and at that time,
As shown in FIG. 9, the notes on the way to the note to be displayed are displayed.

Next, redisplay the standard speed symbol (♪ = 60),
The operation of changing the current price of the displayed note will be explained.

When playing music (especially slow tempo music) that would normally have note values as shown in Figure 10A when displayed at standard speed (♪ = 60), the note values may be too large and difficult to read if displayed as is. In such a case, it is necessary to reduce the market value of the displayed note while keeping the tempo of the music being played the same. 1st
In the figure, when the mode setting switch 15 is operated, the automatic setting mode is entered (step 20 in Figure 2 A), and then the desired speed (for example, speed symbol (♪ = 30)) is selected.
Operate the cycle instruction switch 16 twice at an interval corresponding to . The signal H level is detected by the first operation of the switch 16 (step 37), the period counter 17 is set (step 38), and counting up is started (step 39). switch 16
The signal H level is detected by the second operation (step 40), and as a result, the cycle calculation and cycle data setting section 18 sets switch 1 at step 41.
The operation interval or period of 6 is calculated, and step 42
New cycle/wait data corresponding to ♪=30 is set, and this data is written to the cycle/wait area of RAM7.

Based on this newly set period/weight data, speed symbol pattern data is created in step 43, and "60" on the CRT 14 is created in step 44.
will be redisplayed, for example, as "30". Speed symbol (♪
=30), the process returns to step 20 and the pitch analysis of the input signal is performed. In actual performance, when a C note (equivalent to 2 seconds) as shown in Fig. 10A is input, step 25 is performed as explained above.
This pitch is displayed as an eighth note at step 26, and the program waits for a transition to the next step 27 based on the period/weight data corresponding to ♪=30 written in the RAM 7 at step 26.

After this time has elapsed, this C note is pitch-analyzed again in steps 27-29, a continuous note is determined in step 30, the count is set to 1 in step 20, and the count is set to 1 in steps 32 and 33 as shown in FIG. 10B. A quarter note C note is displayed. Other half-note E, G, and E notes (Figure 10A) from actual performances are also shown in Figure B.
It is displayed as a quarter note as shown in the figure below. In other words,
If you do not change the current price, the pitch will be analyzed four times for 8th notes for 2 seconds and displayed as the note value shown in Figure A, but the pitch will be analyzed twice for 2 seconds for 8th notes. By changing the analysis cycle to a large value, note values can be displayed small.

Contrary to the above example, music with note values that are too small when displayed at standard speed (especially fast-tempo music)
Now, the operation interval of the cycle instruction switch 16 is made small, and the value of the cycle/weight data is made smaller than that of the standard speed, for example, about ♪=240. In this way, when an actual performance at standard speed is played at 32nd notes (8 notes per second) and cannot be displayed, the pitch will be analyzed 8 times at 8th notes per second. By changing the period of pitch analysis to a smaller value, the note value can be displayed larger.

As described above, the musical note display device according to the present invention detects the number of times the frequency of the shortest note to be displayed is analyzed by the frequency analysis means, and calculates the frequency of the notes analyzed before and after by the frequency analysis means. Differences in height and level are detected to determine whether or not the sounds before and after the sound are continuous sounds, and if it is determined that the sounds are continuous sounds, the frequency analysis frequency is set in advance according to the number of analysis times. If a discontinuous sound is determined, the note at the current price set corresponding to the number of analyzes is displayed, and the number of analyzes is cleared, and the standard speed symbol set in advance is displayed. This is set variably for the speed corresponding to the speed, and the cycle of the frequency analysis described above is varied according to the set speed, so the pitch and length of the input sound can be expressed as notes on the staff notation on the display screen. Can be displayed in hours,
Unlike devices that print the notes of the input sound on paper, etc., the score of the music being played can be displayed immediately, making it possible to clearly see the relationship between the music being played and the score, making it useful for music education. and
Also, if you have music with a particularly slow tempo, and if the standard speed symbol is used, each note will be displayed for a longer time than the desired time value. If there is an inconvenience in music where each note cannot be displayed using the standard speed symbol, each note can be displayed by slowing down the tempo, and therefore can be displayed in a desired musical score shape in real time,
Furthermore, by varying the frequency analysis period even when music is played at the same tempo, it has the advantage of being able to correctly display musical notes at easy-to-read market values.

[Brief explanation of the drawing]

FIG. 1 is a block system diagram of an embodiment of the device of the present invention, FIGS. 2A and B are flowcharts for explaining the operation of the device of the present invention, and FIG. 3 is a schematic diagram for explaining some addresses of the RAM in FIG. Figures 4A-I are diagrams showing the relationship between note length and count number, Figure 5 is a diagram showing the relationship between sound level and note, and Figure 6 is CTR.
A diagram of the display screen, Figure 7 is a memory map of the VRAM, Figure 8 is an explanatory diagram of the sections of the CRT display screen, and Figure 9 is for explaining the notes on the way from the eighth note to the displayed note. , and FIGS. 10A and 10B are diagrams comparing sound values based on standard speed symbols and sound values based on variably set speed symbols, respectively. 1...Audio signal input terminal, 4...AD converter,
5...Control device, 6...Conversion command and digital signal output section, 7...RAM, 8...Calculation and pitch analysis section, 9...Continuous sound detection section, 10...Analysis circuit detection and pattern data detection Section, 11...Pattern data determination section, 12...Video display
Processor, 13... V RAM, 14...
CRT, 15...Mode setting switch, 16...
Period instruction switch, 17...Period counter, 18
...Cycle calculation and cycle data setting section.

Claims (1)

[Claims] 1. AD that converts an input audio signal into a digital signal
a conversion means; a frequency analysis means for determining the pitch by time-series frequency analysis of the signal from the AD conversion means at intervals of time according to the length of the shortest note among the notes to be displayed; Frequency analysis frequency detection means detects the number of frequency analyzes by the analysis means, and the frequency analysis means detects the difference in pitch and level of the sounds analyzed before and after, and the sounds before and after are continuous sounds. a continuous sound determining means for determining whether or not a continuous sound is present, and when the continuous sound determining means determines whether a continuous sound is present, a musical note whose market price is set in advance from the number of times of frequency analysis by the frequency analyzing means corresponding to the number of times of analysis; and display means for displaying a note with a current price set corresponding to the number of analyzes when a discontinuous sound is determined by the continuous sound determining means and clearing the number of analyzes; A musical note display device comprising: a frequency analysis period variable means for variably setting a speed corresponding to a standard speed symbol, and varying the frequency analysis period according to the set speed. . 2. The display means converts into predetermined pattern information based on each output from the frequency analysis means, the frequency analysis number detection means, and the continuous sound judgment means, and converts the pattern information into a composite image using a video display processor. The musical note display device according to claim 1, characterized in that the musical note display device is a means for converting the signal into a signal and displaying it on a CRT. 3. The frequency analysis period variable means detects the interval between two consecutive operations of the external operation switch, detects the period, measures the period, and stores the data as frequency analysis period data in the frequency analysis means. The musical note display device according to claim 1 or 2, characterized in that the musical note display device is a means for writing into a memory.