JPH11237879A - Midi data processor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reproduce MIDI data as intended by a MIDI data producer when only MIDI sound sources less than the number of simultaneous sounding described in the MIDI data can be reproduced. SOLUTION: A simultaneous sounding number reducing part 2 reduces the number of simultaneous sounding by remaining the first note event corresponding to a sound, which is most conspicuous in the reproduction among a plurality of note events detected by a same sound detecting part 1, while shortening its duration and by shifting the note-on event of the other second note event on the same track after the note-off event of the said first note event. The simultaneous sounding number reducing part 2 judges the sound having the highest velocity of the note event or having the longest generation time of the note event as the sound to be most conspicuous in the reproduction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system for reproducing MIDI data, for example, in a system such as a communication karaoke system, in which music cannot be reproduced as intended by a MIDI data creator due to the limitation of the number of simultaneous sounds of a sound source. The present invention relates to a MIDI data processing device suitable for a case where a serious data loss occurs.

[0002]

2. Description of the Related Art Generally, MIDI (Musical Instrument D) is used as a means for transmitting performance information for generating musical tones.
Digital Interface) is widely known. This MIDI
Is a standard of hardware and software defined for exchanging information for sounding a sound source of an electronic musical instrument such as a synthesizer or an electronic piano.

[0003] The MIDI information is roughly composed of the following information. (1) Note-like information such as sounding start (note on) indicating a keystroke or the like and sounding stop (note off) indicating a key release or the like. This information also includes information on the pitch indicated by the keyboard number, accent information indicating the strength of pronunciation, and the like. (2) Control information for transmitting a intonation expression to a sound source when a player performs using a damper pedal, lever, or the like.

[0004] The MIDI information can be recorded on a medium as a data file or transmitted via the medium. A commonly used MIDI format is SM
F (Standard MIDI File) is known, but MIDI
Since the information is real-time performance information, when recording and transmitting each information element such as sound generation start (note on event) and sound generation stop (note off event) by this SMF, generation time information is added.

[0005]

By the way, in the case of MIDI information relating to guitars and strings, a plurality of MIDI
In many cases, the same note is multiplexed over the DI channel. However, when such MIDI information is reproduced by a MIDI sound source, M
In some cases, the number of simultaneous sounds of the IDI sound source may be exceeded, and at this time, there is a problem that the reproduction is not performed as intended by the MIDI data creator.

The present invention has been made in view of the above-mentioned conventional problems, and has been developed in consideration of
If the I sound source can reproduce only less than the number of polyphony described in the MIDI data, the MID
MI that can be reproduced as intended by I data creator
It is an object to provide a DI data processing device.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above object, according to the present invention, among a plurality of note events to which the same or similar timbres are simultaneously pronounced, the most prominent sound at the time of reproduction is retained, while leaving the most noticeable sound. It is designed to reduce the number of pronunciations. That is, according to the present invention, the same sound detecting means for analyzing the MIDI data file and detecting a plurality of note events to which the same tone or a similar tone is sounded simultaneously, and the plurality of note events detected by the same sound detecting means. Of the note events, the duration of the first note event corresponding to the most prominent sound during reproduction is shortened, and the note-on event of the other second note event is the note-off of the first note event on the same track. A polyphony reduction means for reducing the number of polyphony by arranging the polyphony after the event
An I data processing device is provided.

Further, according to the present invention, the same sound detecting means for analyzing the MIDI data file to detect a plurality of note events to which the same tone or a similar tone is simultaneously pronounced, and the plurality of note events detected by the same sound detecting means. Out of the plurality of note events, a note event corresponding to the most prominent sound at the time of reproduction is left, and the other note events are deleted to reduce the number of simultaneous sounds by reducing the number of simultaneous sounds. Provided.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of a MIDI data processing apparatus according to the present invention, and FIG.
Is a flowchart for explaining the simultaneous-sounding number reduction processing of the MIDI data processing device of FIG. 3, FIG. 3 is an explanatory diagram showing an example of MIDI data before the simultaneous-sounding number reduction, and FIG. 4 is an illustration showing MIDI data after the simultaneous-sounding number reduction. FIG.

In FIG. 1, the same sound detecting section 1 has a MIDI event buffer for storing note-on events in MIDI data from the time of occurrence thereof to the time of occurrence of note-off events. A plurality of note events to which the same timbre or a similar timbre is assigned are detected. The polyphony reduction unit 2 shortens the duration of the first note event corresponding to the most prominent sound at the time of reproduction from among the plurality of note events detected by the same sound detection unit 1, and leaves the other note events. Is shifted on the same track after the note-off event of the first note event in the same track, thereby reducing the number of simultaneous sounds.
The polyphony reduction unit 2 also deletes other note events from the plurality of note events detected by the same sound detection unit 1 by deleting a note event corresponding to the most prominent sound during reproduction, thereby reducing the polyphony. Reduce. At this time, the polyphony reduction unit 2 determines that the note event having the strongest velocity or the note event with the longest occurrence time is the most noticeable sound during reproduction.

The processing will be described with reference to FIG. First, M
The IDI data stream is opened (step S1), and then a plurality of MIDI events are sorted by the time information (step S2). Next, it is determined whether the next MIDI event is a note-on event or a note-off event (step S3). If the MIDI event is neither a note-on event nor a note-off event, the process is terminated. Step S4
Proceed to the following, and in case of a note-off event, step S
Branch to 10.

In step S4 and subsequent steps, the note-on event is first written into a MIDI event buffer (step S4), and then the time information of the MIDI event is stored in a current time buffer (cur-time) (step S5). Next, it is determined whether there is a note-on event of the same sound and a similar sound in the buffer (step S).
6) If yes, go to step S7 and below; if no, go to step S9.

In step S7 and subsequent steps, the length of the sounds is shortened by changing the generation timing of the note-on event and the note-off event of both sounds so that a plurality of sounds do not sound simultaneously (step S7). Next, the time information of the corresponding MIDI event in the MIDI data stream is changed (step S8). Next, a MIDI event having time information older than a time obtained by subtracting the maximum delta time (the maximum value of the difference between the start times of two note-on events) from the time stored in the current time buffer (cur-time) is defined as a MIDI event. Delete from the buffer (step S9), and then return to step S3. If it is a note-off event in step S3, the note-off event is removed from the MIDI event buffer (step S10).
Return to 3.

FIG. 3 shows, as an example of MIDI data before conversion, note data of tracks "1" and "2" of two guitar phrases which sound simultaneously. The length of the bar shown in FIG. 3 indicates the duration from the start of sound generation (note on) to the stop of sound generation (note off) of one note, which is represented by a note-on event and a note-off event of MIDI data. Note that a piano keyboard is shown on the left side of the figure to explain the scale of the guitar phrase.

As described above, two musical instruments or tones that sound simultaneously may be the same, or one may be a similar guitar such as a steel guitar and the other may be a similar musical instrument such as a nylon guitar. As an example, FIGS. 3A and 3B show a steel guitar and a nylon guitar having notes N1-1 and N2, respectively.
-1 is pronounced simultaneously. Then, the MIDI data of such tracks “1” and “2” is
Even if the MIDI sound source is applied to the DI sound source, if the MIDI sound source has only the sound generation ability for performing one track due to the limitation of the number of simultaneous sounds, the MIDI sound source cannot be reproduced as intended.

FIG. 4 shows an example in which the MIDI data shown in FIG. 3 is converted. Note before conversion N1- pronounced at the same time
1, N2-1 are converted into two notes N1 and N2 so as to be continuous on one track. In this case, the duration of the first note N1 is equal to the pre-conversion note N1-
1, N2-1, the velocity is the shortest by reducing the time information of one note-off event having the strongest velocity or the longest sounding time. The note N2 following the note N1 is the note before conversion N1-1, N2.
The note-on event is moved immediately after the note-off event of the previous note N1, that is, so as not to overlap.

When such data is played on one track, the perceived attack of the note which is more noticeable causes
One track can be played as if the guitar were playing. Therefore, the notes before conversion N1-1, N1-1
The reproduction can be performed as intended by the MIDI data creator, as compared with a case where one of 2-1 is entirely deleted. In addition, by adding a control event to raise the level of the chorus of the sound source, it is possible to reproduce as if the guitar were being played on two tracks in terms of hearing.

[0018]

As described above, according to the present invention, among a plurality of note events to which the same timbre or similar timbre to be simultaneously pronounced is assigned, the number of simultaneous sounds is reduced while leaving the most prominent sound during reproduction. MIDI
If the sound source can reproduce only less than the number of polyphony described in the MIDI data, the MIDI
It can be reproduced as intended by the data creator. In the case where the number of simultaneous sounds is reduced by arranging the note-on event of the second note event after the note-off event of the first note event on the same track as in claim 1, the strong first This is especially effective for sounds like acoustic guitars that decay quickly. Further, when the number of simultaneous sounds is reduced by deleting the note event as in the second aspect, it is particularly effective for the sound of a stringed instrument such as a cello or a violin having a tone that lasts a long time. Furthermore, when the sound having the highest velocity of the note event is determined to be the most prominent sound at the time of reproduction as in claim 3, the possibility of reducing the sound appearing in the front such as a melody is reduced. In the case where the sound with the longest note event occurrence time is determined to be the most prominent sound at the time of reproduction as in claim 4, there is little possibility that a sound such as a bass instrument that has a large effect if interrupted in the middle is reduced. Become.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a MIDI data processing device according to the present invention.

FIG. 2 is a flowchart for explaining a simultaneous sound generation number reduction process of the MIDI data processing device of FIG. 1;

FIG. 3 is an explanatory diagram showing an example of MIDI data before the number of simultaneous sounds is reduced.

FIG. 4 is an explanatory diagram showing MIDI data after the number of simultaneous sounds is reduced.

[Explanation of symbols]

 1 Same sound detection unit (Same sound detection means) 2 Simultaneous sound number reduction unit (Simultaneous sound number reduction means)

Claims (4)

[Claims] 1. A sound detection means for analyzing a MIDI data file to detect a plurality of note events to which the same tone or a similar tone is simultaneously sounded, and a plurality of note events detected by the same sound detection means. Of the above, the duration of the first note event corresponding to the most noticeable sound during reproduction is shortened and the note-on event of the other second note event is set to be shorter than the note-off event of the first note event on the same track. A MIDI data processing device, comprising: a simultaneous-sounding number reducing unit that reduces the number of simultaneous sounds by being arranged later. 2. A sound detection means for analyzing a MIDI data file to detect a plurality of note events to which the same tone or a similar tone is simultaneously pronounced, and a plurality of note events detected by said tone detection means. A MIDI data processing device comprising: a note generation unit that reduces a number of simultaneous sounds by deleting a note event corresponding to a sound that stands out most during reproduction and deleting other note events. 3. The MIDI data processing apparatus according to claim 1, wherein the simultaneous sound generation number reducing unit determines a sound having the highest velocity of the note event as a sound that stands out most during reproduction. 4. The M according to claim 1, wherein the simultaneous sound generation number reducing unit determines a sound having a longest occurrence time of a note event as a most prominent sound during reproduction.
IDI data processing device.