JPH0426895A - musical tone signal generator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a musical tone signal generating device suitable for use in electronic musical instruments and the like.

[Prior Art] To make an electronic musical instrument generate a musical tone that is closest to the musical tone generated by a natural instrument, for example, it is necessary to transfer the musical tone generated by a natural instrument to a PC.
There is a method of storing the data in a memory as M data, reading out the data completely stored in the memory, converting it from D/A, and outputting it.

However, the musical tones of natural instruments are extremely complex;
As described above, the method of simply storing PCM data in memory has the problem that the memory capacity becomes extremely large.

Furthermore, in recent years, there has been an increase in the number of types of electronic musical instruments that switch between and output the musical tones of multiple types of natural instruments using a single electronic musical instrument, and this type of system requires even more memory capacity.

Therefore, it is possible to analyze musical tone signals into PARCOR coefficients and residuals No. 48 in advance and store them in memory, and when generating musical tone signals, read out these data and synthesize musical tone signals. This method is proposed in Japanese Patent No. 61-100796.

[Problem to be solved by the invention] However, even if a method of synthesizing musical tone signals using PARCOR coefficients and residual signals is used, the amount of data required for synthesis is still extremely large, and the synthesis process takes a long time. There was a problem with this. In particular, electronic musical instruments have limited memory capacity, and it is extremely difficult to store enough data to generate multiple types of musical tones.
It was hoped that the amount of data could be reduced even a little.

The present invention was developed in view of this situation, and by reducing the amount of data required for synthesis as much as possible and shortening the synthesis processing time, it can be applied to devices with limited memory capacity such as electronic musical instruments. The present invention aims to provide an adaptable musical tone generator.

[Means for Solving the Problems 1] The musical tone signal generation device according to claim 1 comprises: a coefficient storage means for calculating and storing coefficient information based on the waveform of an external musical tone signal; and a coefficient storage means for storing the musical tone signal. analysis filter means for filtering the coefficient information stored in the coefficient information to generate waveform information; and average value calculation means for calculating the average value of a predetermined range of the coefficient information stored in the coefficient storage means; Coefficient information w1. through this average value calculation means. a coefficient average value storage means for storing coefficient information from the billion means; and a synthesis filter means for filtering the waveform information generated by the analysis filter means in accordance with the coefficient information stored in the coefficient average value storage means. The musical tone signal generating device according to claim 2, further comprising: a coefficient calculation means for calculating coefficient information from an external musical tone signal; and a coefficient calculation means for calculating coefficient information from an external musical tone signal; An average value calculation means for calculating an average value, a coefficient average value storage means for storing coefficient information from the coefficient expenditure means via the average value calculation means, and an average value of the musical tone signal stored in the coefficient average value storage means. analysis filter means for filtering the waveform information obtained by the analysis filter means to generate waveform information in accordance with the average value stored in the coefficient average value storage means; It is characterized by comprising:

[Function] In the musical tone signal generating device according to claim 1, for example, a portion of coefficient information such as a PARCOR coefficient that does not change much is averaged, and a residual value is calculated corresponding to the coefficient information including this average value. Waveform information such as signals is synthesized. Therefore, the amount of data required for synthesis is reduced because the range in which there is no change is only one average value, the memory capacity is reduced, and the synthesis processing time can be shortened.

In the musical tone signal generation device according to claim 2, furthermore, for example, in order to analyze waveform information such as a residual signal, a PA
In a range where there is little change in coefficient information such as the RCOR coefficient, the average value is used. Therefore, the amount of data required for analysis is reduced, and the memory capacity is also small.
It is also important to know the analysis processing time.

[Embodiment] FIG. 1 is a block diagram showing the configuration of an embodiment of the musical tone signal generating device of the present invention.

A musical tone signal inputted from a microphone 1 is A/D converted by an A/D converter (ADC) 2 and written into a waveform RAM 3 as waveform data. The waveform data read from the waveform RΔM3 is sent to the PARCOR coefficient calculation circuit 4 (
coefficient calculation means).

The calculation circuit 4 calculates a PARCOR coefficient (coefficient information) from the input waveform data, and stores the PARCOR coefficient RAM.
5. Store it in (coefficient storage means).

The PARCOR coefficients stored in the RAM 5 are successively retrieved and displayed on the display 7 as necessary.

Further, the PARCOR analysis filter 6 (analysis filter means) analyzes the waveform data completely read out from the RAM 3 using the PARCOR coefficients read out from the RAM 5, and generates a residual signal (waveform information). The residual signal generated by the analysis filter 6 is stored in the residual signal RAM 9.

On the other hand, when the range designation switch 11 is operated, the start address and end address corresponding to the operation are output to the average value calculation circuit 8 (average value calculation means). The average value calculation circuit 8 outputs successive addresses in the range specified by the start address and the end address to the RAM 5, and reads out the PARCOR coefficients in that range. Then, the read PA
The average value of the RCOR coefficients is calculated and stored in the PARCOR coefficient average value RAM10 (coefficient average value storage means).

The PARCOR synthesis filter (2 filter means) converts the residual signal (corresponding to the vocal cord signal of the audio signal) read from the RAM 9 into the PARCO filter read from the RAM 10.
Filter processing is performed using a characteristic (corresponding to the vocal tract characteristic of the audio signal) set by the average value of the R coefficient. Synthesis filter 1
The output of 2 is input to a D/A converter (DAC) 13, subjected to D/A conversion, smoothed by a low-pass filter 14, and output.

The analysis filter 6 is configured as shown in FIG. 2, for example.

In the case of this embodiment, a delay circuit 21 (22...23) that delays input data by a unit clock, and a multiplication circuit that multiplies the input data by a predetermined coefficient - (-2...-) A plurality of stages are provided, each consisting of a circuit 31, 32 (33...36) and an adder 841,42 (43...46) for adding two inputs.

Further, the synthesis filter 12 is configured as shown in FIG. 3, for example.

In this embodiment, a W adder 51. which adds two inputs.
52 (53...56), and the input data has a predetermined coefficient ±
A multiplier 6 that multiplies (±k D-I...± to)
1.62 (63...66) and a delay circuit 71 (72...73) that delays input data by a unit clock.

FIG. 4 is a flowchart showing the operation of calculating the average value in the average value calculation circuit 8.

First, the average values of PARCOR coefficients m k o to mkp
-+, the data number DN is set to 0, and the start address and end address are set in variables ST and END (steps S1 to S3). M:, variable ST is set to read address RD.
is set (step S4).

Next, add the average value mkn to the PARCOR coefficient kn,
Let this be the new average value mkn. Furthermore, the operation of incrementing the successive address RD and the data number DN by 1 is repeated until the successive address RD becomes larger than the end address END (steps S5 to S8).

When the read address RD becomes larger than the end address END, the average value m k , , is divided by the number of data DN, and the quotient is set as a new average value m k , , which is stored (step S9 , 5IO).

FIG. 5 is a block diagram showing the configuration of another embodiment of the musical tone signal generating device of the present invention.

In the embodiment shown in FIG. 1, the PARCOR coefficients stored in the RAM 5 are used to obtain the residual signal by the analysis filter 6, but in this embodiment, the PARCOR coefficients stored in the RAM 10
PARCO that is a predetermined range or average value stored in
The R factor is used.

Other operations are similar to those in FIG.

[Effect of the invention 1] As described above, according to the musical tone (W) generator according to claim 1, for example, a range of coefficient information such as a PARCOR coefficient that does not change much corresponds to its average value. Since the waveform information such as the residual signal is synthesized, the amount of data required for synthesis becomes one average value data in the range where there is not much change, so the amount of data required for synthesis is reduced, and the memory capacity can be reduced. The synthesis processing time can be shortened.

Further, according to the musical tone signal generation device according to the second aspect, for roughly analyzing waveform information such as a residual signal, for example,
For coefficient information such as PARCOR coefficients, the average value is calculated for a range that does not change much, and that average value is used, which reduces the amount of data required for analysis and reduces memory capacity. Analysis processing time can also be shortened.

[Brief explanation of drawings]

1 and 5 are block diagrams showing the configuration of one embodiment of the musical tone signal generating device of the present invention, and FIG. 2 is a block diagram showing the configuration of one embodiment of the analysis filter in FIGS. 1 and 5. , FIG. 3 is a block diagram showing the configuration of one embodiment of the composite plate filter in FIGS. 1 and 5, and FIG. 4 is a flowchart explaining the operation of the average value calculation circuit in FIGS. 1 and 5. be. 1...Microphone 2...A/D converter 3...Waveform RAM 4--PΔRCOR coefficient calculation circuit (coefficient calculation means) 5
... PARCOR coefficient RAM (coefficient storage means) 6 ... Analysis filter (analysis filter means) 8 ... Average value calculation circuit (average value calculation means) 9 - ... Residual signal RAM 10 ... PARCOR coefficient average value RAM (Coefficient average value storage means) 12...Synthesis filter (synthesis filter means) Patent applicant Casio Computer Co., Ltd.

Claims (2)

[Claims] (1) Coefficient storage means for calculating and storing coefficient information based on the waveform of a musical tone signal from the outside; and filter processing of the musical tone signal in accordance with the coefficient information stored in the coefficient storage means, and waveform information for the musical tone signal. analysis filter means for generating an average value of the coefficient information stored in the coefficient storage means; average value calculation means for calculating an average value of a predetermined range of coefficient information stored in the coefficient storage means; Coefficient average value storage means for storing coefficient information; and synthesis filter means for filtering the waveform information generated by the analysis filter means in accordance with the coefficient information stored in the coefficient average value storage means. A musical tone signal generator characterized by: (2) a coefficient calculation means for calculating coefficient information from an external musical tone signal; an average value calculation means for calculating an average value of a predetermined range of the coefficient information calculated by the coefficient calculation means; and this average value calculation. coefficient average value storage means for storing coefficient information from the coefficient calculation means via the means; and filter processing of the musical tone signal corresponding to the average value stored in the coefficient average value storage means to generate waveform information. and a synthesis filter means for filtering the waveform information obtained by the analysis filter means in accordance with the average value stored by the coefficient average value storage means. Generator.