JP2768090B2 - Sound source device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an analysis / synthesis type sound source for analyzing and storing musical tone waveform data for each spectrum and re-synthesizing them to form a musical tone signal. The present invention relates to a method for generating musical tone waveform data.

[0002]

2. Description of the Related Art Various tone signal forming methods for electronic musical instruments have been conventionally proposed. The main one is FM
There are a system sound source and a waveform memory system sound source. The FM system sound source is a system in which a plurality of basic signals are synthesized (frequency-modulated) by various algorithms and intensities to form musical sound waveform data.
The waveform memory system is a system in which musical sounds of natural musical instruments are stored in a memory in time series, and when sound is generated, these are sequentially read out to form musical sound waveform data.

[0003]

In the FM system sound source, the waveform can be controlled flexibly and flexibly by adjusting the parameters. However, it is difficult to control the waveform to the intended tone and the reproducibility of a natural musical instrument is poor. Was. The sound source of the waveform memory system has good reproducibility of musical tones of natural musical instruments, but it is difficult to process the waveform, so that it is not possible to change the timbre. Further, when there are a plurality of tone data, it is difficult to generate an intermediate tone color in any of the FM system sound source and the waveform memory system sound source. That is, the FM system sound source has a property that the intermediate value of each parameter is never the intermediate value of the timbre, and the waveform memory sound source can generate significant data even if the intermediate value of the data is taken at each sampling timing. Did not.

SUMMARY OF THE INVENTION An object of the present invention is to provide a sound source device having good reproducibility of the timbre of a natural musical instrument and good controllability of a waveform, and to generate a new timbre other than the timbre sampled by the sound source device. To be able to do it.

[0005]

SUMMARY OF THE INVENTION The present invention relates to an analyzing means for dividing musical tone waveform data into a plurality of partial data and processing each partial data into an analysis parameter consisting of spectrum frequency data and intensity data. Shifting means for shifting the parameters to the analysis parameters of the standard frequency, re-synthesizing means for re-synthesizing the musical tone waveform data from the shifted analysis parameters, Re-analyzing means for analyzing frequency data and intensity data of a spectrum for each partial data; storage means for storing frequency data and intensity data of the spectrum for each partial data analyzed by the re-analyzing means as analysis parameters; A new analysis parameter is obtained by interpolating the multiple types of analysis parameters stored in And interpolation means for generating a meter and a synthesizing means for re-synthesizing tone waveform data are sequentially read out this new analysis parameters, comprising the.

[0006]

The sound source apparatus according to the present invention extracts analysis parameters relating to a spectrum from musical tone waveform data of a standard frequency and stores them. In the case of tone waveform data other than the standard frequency, the analysis parameters are once extracted, shifted to the standard frequency, and the tone waveform data is re-synthesized, analyzed, and stored.

When musical tone waveform data is formed for sound generation, analysis parameters are sequentially read and synthesized. This makes it possible to form musical tone waveform data with good reproducibility similar to that of the waveform memory, and to freely adjust the analysis parameters, so that tone processing is easy.

Furthermore, since the analysis parameters stored in the storage means are for the same standard frequency, new analysis parameters can be generated by interpolating a plurality of analysis parameters for each spectrum.
By re-synthesizing this, new musical sound waveform data can be generated.

[0009]

FIG. 1 is a block diagram of a basic circuit of an analysis and synthesis system sound source to which the present invention is applied.

This sound source has an analyzing unit 1, a storing unit 2, an interpolating unit 3, a shifting unit 4, and a synthesizing unit 5. FIG. 2 shows the configuration of the analysis unit 1. The analysis unit 1 has a configuration in which a plurality (128) of band-pass filters (BPFs) are connected in parallel. Each BPF is identified by a channel number of channels 0 to 127. The bandwidth of each BPF is 125 Hz, and its filtration band is 0 channel: 0 to 125 H
z, one channel: 125 to 250 Hz, three channels: 250 to 375 Hz, from 0 Hz to 16 k
Hz. Furthermore, this BPF is F
It has an FT function, and can detect frequency data and intensity data Mag of a spectrum passing through the BPF. The frequency is detected as a deviation from the band center frequency. By adding the deviation to the band center frequency, frequency data Freq of an absolute value is obtained. The analysis unit 1 can be composed of a BPF array as described above,
It can also be realized using a high-speed FFT analyzer. Further, the number of channels is not limited to 128, and the bandwidth is not limited to 125 Hz.

The analyzer 1 receives PCM waveform data. The PCM waveform data is sampled with a sampling clock of 32 kHz. The analysis unit 1 handles continuous 2048 samples as one set of data (one frame). However, each frame is output every 64 samples, and adjacent frames overlap with a shift of 64 samples (see FIG. 3). Analysis unit 1
When one frame of sampling data is input, each channel outputs frequency data Freq and intensity data Mag of the frame. Here, the number of samples forming one frame is not limited to 2048, and the frame interval is not limited to 64 samples.

[0012] The storage unit 2, the frequency data F ^m _n and intensity data M ^m _n of each channel are stored as a table for each frame (Fig. 4). A group of tables of a plurality of frames corresponding to one waveform data is called voice data. This voice data is stored for each tone. In the case of multi-sampling (a method of storing a plurality of waveforms of one timbre for each tone range or intensity), one timbre includes a plurality of voice data.

The analysis of the waveform data (converted into voice data) by the analysis section 1 and the storage in the storage section 2 are pre-processes performed before the performance.

The interpolation section 3 is a circuit section for forming data of each sampling clock when reading voice data and forming waveform data. That is, although the frame data is output every 64 clocks, 6 frames between each frame are output.
Frequency data and intensity data at three sampling timings are calculated by linear interpolation from the frame data before and after that (see FIG. 5). The interpolation is performed using the same channel data for each channel. The calculated data is output to the shift unit 4.

The shift unit 4 is a circuit that shifts only frequency data in order to generate a musical tone having a pitch (frequency) specified by a keyboard or the like. The shift amount is determined based on the frequency of the sampled waveform data and the designated frequency.

The synthesizing section 5 is a circuit for synthesizing frequency data and intensity data for each channel to synthesize one waveform data. The synthesis may use an inverse FFT synthesis or an addition synthesis.

Voice data stored in the storage section 2 is read out, interpolated and shifted for each channel, and then synthesized to form musical sound waveform data.
Therefore, the operations of the storage unit 2, the interpolation unit 3, the shift unit 4, and the synthesis unit 5 are real-time operations during performance.

The analysis / synthesis sound source of the above-described method can form an electronic sound by sampling an actual sound such as a natural musical instrument, and can greatly process the sampled waveform data.

FIG. 6 is a diagram for explaining a procedure of analyzing and synthesizing musical tone waveform data executed by the tone generator having the above-mentioned configuration.
FIG. 7 is a diagram showing an example of the spectrum of the musical sound waveform data. In the procedure of FIG. 6, n1 to n5 are pre-processes for generating PCM data (data in which the extracted analysis parameters are stored in the storage unit 2) input to the analysis unit 1. First, the original PCM data is analyzed
(N1: FIG. 7A). The PCM data includes a fundamental wave and a formant (harmonic spectrum) which is a harmonic component thereof, and each of them is included in a BPF filtration band of any channel. Analysis unit 1
The PCM data is converted into analysis parameters for each of 128 channels and 64 samples (n2, n3).
In this state, it cannot be interpolated with other tone waveform data ((D) in the figure) which is converted into an analysis parameter at the standard frequency. This is because the interpolation between the analysis parameters is performed between the parameters of the same channel number, so that the channel number remains unchanged even if the analysis parameters are shifted as shown in FIG. Therefore, the analysis parameters are shifted to the standard frequency in the shift unit 4 (n4: FIG. 7B), and the shifted analysis parameters are re-synthesized in the synthesis unit 5 to obtain musical sound waveform data (n
5). The tone waveform data (PCM data) is input to the analysis unit 1 again and analyzed into analysis parameters (n6: FIG. 7).
(C)). Since the analysis parameters are of the standard frequency, a new voice can be generated by interpolating with other musical sound waveform data analyzed and stored at the standard frequency.
However, the intensity may be negative due to sampling or shifting. Since the sign varies depending on the analysis parameter, if a plurality of types of analysis parameters are interpolated as they are, their components are canceled out, resulting in a thin sound or noise. Therefore, all the intensity data are converted into absolute values (n7) and stored in the storage unit 2 (n
8). When this analysis parameter is compared with the analysis parameters of the other tone waveforms (FIG. (D): n10), the intensity of each spectrum is different but the distribution is the same. Therefore, by performing interpolation for each channel (n11), it is possible to generate a new musical sound waveform analysis parameter (n12). By adding and combining (n13), new musical tone waveform data can be formed (n14).
In order to obtain musical sound waveform data of any frequency,
After the interpolation, the signal may be shifted to a predetermined frequency in the shift unit and recombined.

[0020]

As described above, according to the present invention, the reproducibility of musical tones such as natural musical instruments is improved by using the sampled data, and the tone is stored as a frequency-analyzed parameter, so that the processability of timbre is high. A sound source device can be realized. In addition, since the analysis parameters of all timbres are stored at the standard frequency, any intermediate timbre can be generated by interpolation, which leads to an improvement in expressiveness.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of an analysis and synthesis system sound source to which the present invention is applied.

FIG. 2 is a diagram showing a configuration of an analysis unit of the analysis and synthesis system sound source.

FIG. 3 is a diagram showing an example of PCM waveform data input to the analysis and synthesis system sound source.

FIG. 4 is a diagram showing storage contents of a storage unit of the analysis and synthesis system sound source.

FIG. 5 is a view for explaining the operation of the interpolation unit of the analysis / synthesis system sound source.

FIG. 6 is a diagram showing an analysis / synthesis procedure executed in the analysis / synthesis system sound source.

FIG. 7 is a diagram showing an example of a spectrum of musical tone waveform data to be analyzed;

[Explanation of symbols]

1-analysis unit, 2-storage unit, 3-interpolation unit, 4-shift unit,
5- Synthesis part.

Claims (1)

(57) [Claims] A musical tone waveform data is divided into a plurality of partial data, and spectrum frequency data,
Analysis means for processing into analysis parameters consisting of intensity data; shift means for shifting the analysis parameters to analysis parameters of the standard frequency; resynthesis means for resynthesizing the tone waveform data from the shifted analysis parameters; Re-analyzing means for dividing the musical tone waveform data into a plurality of partial data again, and analyzing spectrum frequency data and intensity data for each partial data; and a spectrum frequency for each partial data analyzed by the re-analyzing means. Storage means for storing data and intensity data as analysis parameters; interpolation means for interpolating a plurality of types of analysis parameters stored in the storage means for each spectrum to generate new analysis parameters; Combining means for sequentially reading and resynthesizing the musical tone waveform data. Sound source device according to claim.