Music – Instruments – Electrical musical tone generation
Reexamination Certificate
1999-07-23
2001-04-17
Witkowski, Stanley J. (Department: 2837)
Music
Instruments
Electrical musical tone generation
C084S622000, C084S661000, C084S47700R, C084SDIG009
Reexamination Certificate
active
06218604
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a tone generator, a waveform memory addressing method, and a machine readable medium suitable for use in generating tones in an electronic musical instrument or else.
2. Description of Related Art
A known sampler is constructed such that an analog tone signal is converted into a digital waveform sample composed of a series of digital values, then the same is stored in a waveform memory along a given range of addresses, and a desired music tone is reproduced based on the stored waveform sample. In such a sampler apparatus, a user specifies a read start address, a loop start address, and an end address of the waveform memory. When performance information is inputted, the waveform sample is read once from the read start address to the loop start address, followed by repeated reading of the waveform sample from the loop start address to the end address by the number of times corresponding to a duration of the music tone specified by performance information. Based on the waveform data thus read, the music tone is generated.
The above-mentioned read start address, loop start address, and end address may be changed to generate music tones of different variations based on one type of the waveform sample. However, to read waveform data of a different variation, the conventional sampler must set the addresses of the waveform data from a first step, making it impossible to generate music tones while changing their variations during the course of music performance.
SUMMARY OF THE INVENTION
It is therefore a first object of the present invention to provide a tone generator, a waveform memory addressing method, and a machine readable medium that are capable of generating as desired diverse variations of a music tone based on the same waveform sample.
It is a second object of the present invention to provide a tone generator, an addressing method, and a machine readable medium that are capable of setting two or more addresses to one type of a waveform sample by means of a user-friendly interface.
According to the invention, a tone generator apparatus comprises a waveform memory having addresses for storing a plurality of waveform samples, each waveform sample comprising a series of digital values located sequentially along the addresses, waveform selecting means for selecting the waveform samples stored in the waveform memory, an address memory for storing a set of start addresses in correspondence to each waveform sample, the start addresses specifying different addresses from which the same waveform sample is to be variably read out, address designating means for designating a default start address among the set of the start addresses to read out the waveform sample from the default start address, a set of controls manually operable to command generation of a musical tone, diversifying means for commanding whether or not to undergo diversification of the start address of the waveform sample, reading means operative when the diversification is not commanded for reading each waveform sample from the default address in response to operation of a corresponding control, and being operative when the diversification is commanded for reading the selected waveform sample from one start address selected from the set of the start addresses in correspondence to the operated control, and synthesizing means for synthesizing the musical tone according to the read waveform sample.
Preferably, the inventive tone generator apparatus further comprises a filter memory for storing a default filter parameter in correspondence to each waveform sample, and for storing a set of variational filter parameters, wherein the diversification means includes means for commanding whether or not to undergo diversification of a filtering process, and wherein the synthesizing means operates when the diversification of the filtering process is not commanded for undergoing the filtering process of the read waveform sample based on the default filter parameter, and operates when the diversification of the filtering process is commanded for applying the filtering process to the read waveform sample by using one of the variational filter parameters selected in correspondence to the operated one of the controls.
According to the invention, a method of determining a set of start addresses used for variably reading one waveform sample, comprises the steps of storing the waveform sample in a waveform memory, detecting a plurality of rising points involved in the waveform sample, quantizing a segment of the waveform sample around each rising point to evaluate a magnitude associated to each rising point, and sorting the detected rising points in terms of the magnitudes so as to select significant ones of the detected rising points to thereby determine the set of the start addresses.
According to the invention, a method of determining a set of start addresses used for variably reading one waveform sample in correspondence to a set of manual controls, comprises the steps of storing the waveform sample in a waveform memory along a range of addresses, sequentially reading the waveform sample form the range of the addresses to generate a musical tone, operating one of manual controls during the generation of the music tone, and capturing an instant address from the range in coincident with a timing of operating the manual control to thereby determine the start address in association with the operated manual control.
According to the invention, a machine readable medium is used in a music apparatus having a processor, a set of controls manually operable to input a performance event, and a waveform memory storing an original waveform sample composed of a series of digital values sequentially readable from a default start address. The medium contains program instructions executable by the processor for causing the music apparatus to perform a tone generating process in response to the performance event. The tone generating process comprises the steps of scanning the original waveform sample to determine a set of variational start addresses which are diverging from the default start address and which are allotted to corresponding ones of the controls, detecting an operated control among the plurality of the controls, specifying one of the variational start addresses corresponding to the operated control upon detection thereof, reading the original waveform sample from the specified variational start address to provide a variational waveform sample which is diversified from the original waveform sample uniquely to the specified variational start address, and synthesizing a musical tone unique to the operated control in accordance with the provided variational waveform sample and in response to the performance event.
Specifically, in the machine readable medium, the step of scanning comprises locating a plurality of rising points involved in the series of the digital values of the original waveform sample, quantizing a segment of the digital values around each rising point to evaluate a magnitude associated to each rising point, sorting the located rising points in terms of the magnitudes so as to select significant ones of the rising points to thereby determine the set of the variational start addresses.
Specifically, in the machine readable medium, the step of scanning comprises provisionally reading the original waveform sample while incrementing addresses of the digital values of the original waveform sample to generate a musical tone, detecting a timing when one of the controls is operated during generation of the musical tone, and capturing an instant address coincident with the detected timing to determine the variational start address to be allotted to the operated control.
REFERENCES:
patent: 3821714 (1974-06-01), Tomisawa et al.
patent: 4383462 (1983-05-01), Nagai et al.
patent: 4622877 (1986-11-01), Strong
patent: 4947723 (1990-08-01), Kawashima et al.
patent: 5225619 (1993-07-01), Sharp
patent: 5430241 (1995-07-01), Furuhashi et al.
patent: 567750
Morrison & Foerster
Witkowski Stanley J.
Yamaha Corporation
LandOfFree
Tone generator with diversification of waveform using... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Tone generator with diversification of waveform using..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Tone generator with diversification of waveform using... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2480449