KR950010336B1 - Compression and reproducing method of music data - Google Patents

Abstract

The device provides music data compression/expansion method for the Karaoke system by substituting the repeated part into a specialized symbol. The method comprises the steps of extracting the repeated music data interval as a first repeating part; assigning a specialized symbol to the first repeating part; assigning a different symbol to the repeating part if the music data forms another repeated part; and recording the start address and the number of repetition.

Description

Compression and Playback Method of Music Data

1 is a block diagram of a general song accompaniment system.

2 is a schematic diagram of MIDI file data in a conventional song accompaniment system.

3 is a block diagram of repeating track data in the song accompaniment system of the present invention.

4A is a diagram showing a data extraction process of the repeat track of the present invention, and FIG. 4B is a diagram showing an example of data creation of the extracted repeat track of the present invention.

* Explanation of symbols for main parts of the drawings

1: data storage unit 2: data analysis unit

3: sound generator

The present invention relates to a method of compressing music data and a method of reproducing compressed data. In particular, when a large amount of music data is stored as in a song accompaniment system, the music data is replaced by a compression code that replaces a repeated portion during music performance. The present invention relates to music data, a compression method, and a playback method, which can reduce the size of the music.

A general song accompaniment system, as shown in FIG. 1, converts music data stored in the data storage unit 1 and music data stored in the data storage unit 1 into MIDI (Musical Instrument Digital Interface) signals. A data generator (2) and a sound generator (3) for receiving a converted MIDI signal and generating a music signal, and with reference to FIG. 1, music data storage and reproducing method of the conventional song accompaniment system. This is as follows.

First, when music data is stored in a data storage unit 1 in which a ROM, a disc, or the like is used in accordance with a standard designated as a standard MIDI file, since the standard MIDI file does not have a command for setting a repeating unit such as a dodol table, When a certain pattern is frequently repeated, such as a base or a base, or when almost similar data are repeated, such as section 1 and 2, it must be repeatedly stored in the data storage unit 1.

The standard MIDI file specification consists of a contiguous set of time data and data divided into MIDI data, as shown in FIG. 2. The value of the time data is from the previous MIDI event to the current event. This value is given by a constant resolution (determined by the tempo and analysis used for each song).

Therefore, the data stored in the data storage unit 1 is calculated by applying the MIDI data to the sound generating unit 3 after calculating the time value as described above in the data analysis unit 2, so that music is played.

However, in the conventional music accompaniment system, the music data storage and reproducing method stores the music data in the data storage unit 1 in accordance with a standard designated as a standard MIDI file, and the MIDI file has instructions for setting a repeating unit such as a dodol table. If a certain pattern such as a drum or a bass is frequently repeated, or when almost similar data such as a section 1 or 2 is repeated, it is repeatedly stored in the data storage, thereby increasing the amount of data to be stored. When storing songs, there is a problem that there is insufficient space to store or the size of the medium to be stored increases.

In order to solve such a conventional problem, the present invention is provided with a repeating function in the data storage unit, when the music data is stored in a data storage unit in accordance with a standard designated as a standard MIDI file. By replacing parts with simple codes and storing them in the data storage unit, a large amount of songs can be compressed and stored, and its purpose is to be able to compress and store MIDI data for each MIDI channel.

A compression method of music data of the present invention which achieves the above object comprises: a first step of extracting, as a first repeating unit, specific data repeated from a series of music data; A second process of substituting a specific symbol to the first repeater extracted in the first process; A third step of extracting the repeating part and giving another specific sign when the series of musical data including the specific sign given in the second step forms another second repeating part; And a fourth step of recording an address at which the repetition part starts and a number of each repetition part in the first and third steps.

Here, the series of music data is MIDI data.

The music data reproducing method of the present invention which achieves the above object comprises the steps of: reading a number of repetitions of a series of music data; A second step of reading an address at which the repeat of the series of music data starts; A third process of reading data corresponding to the repeating portions of the first process and the second process; And a fourth process of restoring and reproducing the original music data from all the above processes.

Here, the series of music data is MIDI data.

Hereinafter, a compression method and a reproduction method of music data of the present invention will be described with reference to FIGS. 1 to 4.

First, referring to FIG. 1, a data storage unit 1 using a ROM or a disc is divided into a repeating track and a playing track, and the extracted repeating section and related information are stored in the repeating track. In the performance track, actual performance data is compressed and stored using the repeater.

At this time, as shown in FIG. 3, the music data stored in the repeating track is stored in the head of the data, the number of repeating parts used when playing music, and then the address of the data at which each repeating part starts. Store as many as possible, and store each iteration at each corresponding address so that it can be used when playing data on a performance track.

The extraction process of the northern part is as follows. Extract the repeated part of the entire performance data and replace it with a single chord (specific code) Create a second repeat.

An example of data compression of the present invention is shown in FIGS. 4A and 4B.

In the case of music data such as (ABC, ABC, ABCD, ABCD, ABC, ABC, ABCD, ABCD), first, the frequently repeated (ABC) is extracted to the first iteration and replaced with the code "X".

If you replace frequently repeated (ABC) with chord "1", the performance data will be [XXXDXD, XXXDXD]. From this data, repeat (XXXDXD) with a second iteration and replace with "Y". Becomes (YY).

The resulting (YY) is stored in the performance track, and data is stored in the repeat track as shown in (b) in FIG.

When reproducing music data stored in the data storage unit 1, the data analyzing unit 2 first reads and stores the number of sound data and the repeating unit including a specific signal corresponding to the repeating unit, and then repeats the number of repeating units. Find the address where each iteration of the note data begins.

When playing a performance track, if a repeating code ("X" or "Y" in the example of FIG. 4) that indicates a repeating part is found in the playing data, the playing data is found from the address of the repeating part.

That is, in the case of the example of FIG. 4, when the repeating section code "Y" appears in the playing data, it finds (XXXDXD) contained in the address [nnnn] of the repeating section "Y", and again the address of the repeating section "X" [mmmm] If (ABC) contained is found and exported as a MIDI signal, the sound generator 3 generates a sound using the MIDI signal.

After the first iteration "X" (ABC) is finished, go back to the next position of the iteration "Y" and play the next chord "X" → "X" → "X" → "D" → "X" When you have finished playing the repeating "X", go back to the playing track and play the next repeating "Y".

As described above, by replacing the repeated portion with a simple code when playing music and storing it in the data storage, a large number of songs can be recorded.

Claims (4)

A first step of extracting specific data repeated from the series of music data as a first repeating unit; A second process of substituting a specific symbol to the first repeater extracted in the first process; A third step of extracting the repeating part and giving another specific sign when the series of musical data including the specific sign given in the second step forms another second repeating part; And a fourth step of recording an address at which the repetition part starts and the number of each repetition part in the first step and the third step. The method of claim 1, wherein the series of music data is MIDI data. A first step of reading the number of repeat portions of the series of music data; A second step of reading an address at which the repeat of the series of music data starts; A third process of reading data corresponding to the repeating portions of the first process and the second process; And a fourth step of restoring and reproducing original music data from all the above steps. 4. The method of claim 3, wherein the series of music data is MIDI data.