Electronic musical instrument, method, and storage medium

Patent metadata

Field	Value
Publication number	US-10559290-B2
Application number	US-201916359567-A
Country	US
Kind code	B2
Filing date	Mar 20, 2019
Priority date	Mar 22, 2018
Publication date	Feb 11, 2020
Grant date	Feb 11, 2020

Abstract

An electronic musical instrument includes a sound source LSI to generate a musical sound using a RAM that retains waveform data that has been selectively read from a plurality of waveforms stored in a large-capacity flash memory, and smoothly executes transfer of additional waveform data from the flash memory to the RAM when the requisite waveform data is not retained in the RAM during the performance. Performance data is generated by a sequencer, a prescribed delay time is applied to the performance data by an event time generator and an event delay buffer so as to provide for sufficient time for the transfer of the additional waveform if such transfer is needed. A musical sound is generated by an event buffer and a sound source driver on the basis of the delayed performance data.

First claim

What is claimed is:

1. An electronic musical instrument comprising:
a plurality of playing keys to be operated by a user for generating a real time sound generation event to be outputted from the musical instrument in real time;
a first memory that stores a plurality of waveforms to be used in automatic performance that is outputted by the musical instrument in accordance with automatic performance data so as to accompany the real time sound generation event;
a second memory having faster access speed than the first memory, the second memory including an event buffer for storing data for the real time sound generation event specified by the user operation of the playing keys and data for the automatic performance, the second memory further including a plurality of waveform buffers for retaining data for waveforms to be used in sound production; and
at least one processor,
wherein the at least one processor performs the following:
causing the automatic performance data to be generated, the automatic performance data including an identifier to specify a waveform used in the automatic performance, data that specifies events included in the automatic performance, and data that indicates a playback timing of each of said events in the automatic performance;
searching the plurality of waveform buffers in the second memory to determine whether any of the plurality of waveform buffers retains the waveform specified by the identifier in the automatic performance data;
if the searching determines that none of the plurality of waveform buffers retain the specified waveform, accessing the first memory, retrieving the specified waveform from the first memory, and causing the specified waveform to be retained in one of the plurality of waveform buffers in the second memory that is available or is caused to be available;
causing the playback timing of each of said events in the automatic performance data to be delayed by a prescribed delay time to generate delayed automatic performance data that include said events with the delayed playback timings, and causing the delayed automatic performance data to be stored in the event buffer, the prescribed delay time being such that the transfer and retention of the specific waveform from the first memory to the second memory are completed during the prescribed delay time; and
accessing the event buffer to retrieve said data for the real time sound generation event and said delayed automatic performance data and causing a sound corresponding to the user operation of the playing keys and a sound of the automatic performance to be generated and outputted from the musical instrument in accordance with the retrieved data for the real time sound generation event and the retrieved delayed automatic performance data.

2. The electronic musical instrument according to claim 1 , further comprising an event time generator that is a clock circuit that counts the prescribed delay time,
wherein the at least one processor causes the event buffer to store the data indicating the events delayed by the prescribed delay time, based on a count value produced by the event time generator.

3. The electronic musical instrument according to claim 2 ,
wherein the at least one processor causes the playback timing of each of said events in the automatic performance data to be delayed by the prescribed delay time by using a region of the second memory as a delay buffer.

4. The electronic musical instrument according to claim 1 ,
wherein the identifier in the automatic performance data includes information on a tone color number, a key number, and a key stroke velocity, and the at least one processor determines a waveform number specifying the waveform used in the automatic performance on the basis of the key number and the key stroke velocity.

5. The electronic musical instrument according to claim 1 ,
Wherein a number of the plurality of waveform buffers in the second memory correspond to a number of sounds that can be generated simultaneously by the musical instrument.

6. A method of sound generation performed by an electronic musical instrument that includes:
a plurality of playing keys to be operated by a user for generating a real time sound generation event to be outputted from the musical instrument in real time;
a first memory that stores a plurality of waveforms to be used in automatic performance that is outputted by the musical instrument in accordance with automatic performance data so as to accompany the real time sound generation event;
a second memory having faster access speed than the first memory, the second memory including an event buffer for storing data for the real time sound generation event specified by the user operation of the playing keys and data for the automatic performance, the second memory further including a plurality of waveform buffers for retaining data for waveforms to be used in sound production; and
at least one processor,
the method comprising via said at least one processor:
causing the automatic performance data to be generated, the automatic performance data including an identifier to specify a waveform used in the automatic performance, data that specifies events included in the automatic performance, and data that indicates a playback timing of each of said events in the automatic performance;
searching the plurality of waveform buffers in the second memory to determine whether any of the plurality of waveform buffers retains the waveform specified by the identifier in the automatic performance data;
if the searching determines that none of the plurality of waveform buffers retain the specified waveform, accessing the first memory, retrieving the specified waveform from the first memory, and causing the specified waveform to be retained in one of the plurality of waveform buffers in the second memory that is available or is caused to be available;
causing the playback timing of each of said events in the automatic performance data to be delayed by a prescribed delay time to generate delayed automatic performance data that include said events with the delayed playback timings, and causing the delayed automatic performance data to be stored in the event buffer, the prescribed delay time being such that the transfer and retention of the specific waveform from the first memory to the second memory are completed during the prescribed delay time; and
accessing the event buffer to retrieve said data for the real time sound generation event and said delayed automatic performance data and causing a sound corresponding to the user operation of the playing keys and a sound of the automatic performance to be generated and outputted from the musical instrument in accordance with the retrieved data for the real time sound generation event and the retrieved delayed automatic performance data.

7. A non-transitory computer-readable storage medium having stored thereon a program executable by at least processor contained in an electronic musical instrument, the electronic musical instrument further including:
a plurality of playing keys to be operated by a user for generating a real time sound generation event to be outputted from the musical instrument in real time;
a first memory that stores a plurality of waveforms to be used in automatic performance that is outputted by the musical instrument in accordance with automatic performance data so as to accompany the real time sound generation event; and
a second memory having faster access speed than the first memory, the second memory including an event buffer for storing data for the real time sound generation event specified by the user operation of the playing keys and data for the automatic performance, the second memory further including a plurality of waveform buffers for r

Assignees

• Casio Computer Co Ltd

Inventors

• Sato Hiroki
• Kawashima Hajime

Classifications

• G10H2240/311

  MIDI transmission (G10H2240/056 takes precedence) · CPC title

• G10H7/00

  Instruments in which the tones are synthesised from a data store, e.g. computer organs · CPC title

• G10H1/0033 Primary

  Recording/reproducing or transmission of music for electrophonic musical instruments · CPC title

• G10H1/24

  for selecting plural preset register stops · CPC title

• G10H1/22

  for suppressing tones; Preference networks · CPC title