KR100264389B1 - Computer music cycle with key change function - Google Patents

Abstract

PURPOSE: A computer music accompaniment device is provided to convert a tempo and a key of MIDI(Musical Instrument Digital Interface) music at the same time in response to a key convert command while playing the MIDI music. CONSTITUTION: A pre-encoding unit(100) stores data and parameter about key and tempo for a tempo converting decoding unit(108) and a key convert decoding unit(110) to decoding data in real time. The tempo converting deciding unit included in an MPEG(Moving Picture Expert Group) decoder(106) receives a tempo convert encoder data from a data store unit(102) for reproducing a waveform of a converted tempo. The key convert decoding unit in the MPEG decoder receives tempo converted data from the tempo convert decoding unit for reproducing in real time by synthesizing with a key convert signal.

Description

Computer music cycle with key change function

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a computer music cycle, and more particularly, to a computer music cycle that can implement a key conversion function for voice chorus data.

FIG. 1 is a block diagram showing the configuration of a computer music cycle according to the prior art. In order to output a voice chorus to an output unit 24, a control data is transmitted from a system controller 14 to a controller 12. The controller 12 outputs a data output request command to the data storage unit 10. The data storage unit 10 exports the audio MPEG encoded data to the MPEG decoder 18 (hereinafter referred to as "MPEG decoder"). The MPEG decoder 18 decodes the audio MPEG decoder data and stores it in a buffer therein. The system control unit 14 outputs the MIDI control signal to the MIDI control unit 16 and outputs a command to the controller 12 in synchronization with the MIDI control signal. The controller 12 outputs a SYNC control signal to the MPEG decoder 18 according to a command received from the system controller 14. At this time, the MPEG decoder 18 outputs the audio MPEG decoder data in the buffer to the key converting unit 20 when receiving the synchronous control signal from the controller 12. The key converting unit 20 performs the key converting process only when the key converting command is received from the controller 12, and bypasses the key converting process. The key converting unit 20 outputs PCM data, and the D / A converting unit 22 converts the PCM data into an analog signal and outputs the analog signal to the output unit 24.

However, the conventional computer music musical cycle constructed as described above causes many problems because the MPEG decoder does not have a tempo converter and a key converter. That is, since the MPEG decoder does not have a built-in tempo converter, the voice chorus does not become tempo variable when a tempo variable is required, causing a mute phenomenon. In addition, since the key converting unit is separately installed outside the MPEG decoder, the hardware is not only complicated, the cost is increased, and signal processing is performed without considering the cross correlation, so that the sound quality loss may occur when the key conversion occurs. Noise caused a lot of problems.

Therefore, in order to solve such a problem, a computer music cycle having a tempo conversion unit built in an MPEG decoder has been developed, which is a domestic application number: 97-82680 (name: computer music cycle having a TEMPO conversion function) (hereinafter referred to as “preceding”). Technology ”.

However, the prior art as described above has to install a key converting part separately because only the tempo converting part is embedded in the MPEG decoder, which causes cost increase, hardware complexity, and sound quality loss.

Accordingly, an object of the present invention is to provide a computer music cycle that can simultaneously implement the tempo conversion and key conversion of the MIDI music when the key conversion is requested while playing the MIDI music.

Another object of the present invention is to provide a computer music cycle that can simultaneously implement the tempo conversion and key conversion of the voice chorus when a key conversion is requested during MIDI music performance.

In order to achieve the above object, a computer music repeating cycle having a key converting function of the present invention comprises: a pre-encoding device for storing encoder data for tempo conversion and key conversion; A data storage unit for storing the encoder data and voice chorus data; A controller for outputting a voice chorus request signal in response to a key conversion request command output from the system controller; A data controller which stores the encoder data and voice chorus data and transmits key and tempo encoder data in response to the voice chorus request signal; An MPEG decoder unit for receiving audio MPEG decoder data from the data storage unit and storing the audio MPEG decoder data in an internal buffer; A tempo conversion decoding unit installed inside the MPEG decoder and receiving tempo conversion encoder data from the data storage unit for tempo conversion and reproducing a waveform of the converted tempo in real time; It is installed inside the MPEG decoder, and the key conversion decoding unit for receiving the tempo-converted data from the tempo conversion decoding unit for the key conversion to synthesize the key conversion signal to reproduce in real time.

1 is a block diagram showing the configuration of a computer music cycle in accordance with the prior art.

2 is a block diagram showing the configuration of a computer music cycle having tempo conversion and key conversion functions in accordance with a preferred embodiment of the present invention.

3 is a block diagram showing the configuration of a key and tempo conversion pre-encoding device in a computer music cycle.

4 is a graph showing a state in which the waveform of the tempo converted by the tempo conversion decoding unit in the computer music half cycle of the present invention in real time.

5 is a graph showing the waveform of the key signal converted by the key conversion decoding unit in the computer music cycle period of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, it should be noted that only parts necessary for understanding the operation according to the present invention will be described, and descriptions of other parts will be omitted so as not to obscure the subject matter of the present invention.

1 is a block diagram showing the configuration of a computer music cycle having tempo conversion and key conversion functions according to an embodiment of the present invention. In the drawing, reference numeral 100 denotes a pre-encoding device, which is used to convert the key and tempo conversion so that the tempo conversion decoding unit 108 and the key conversion decoding unit 110 built in the MPEG decoder 106 decode the data in real time. It is a device that stores related data and parameters. That is, the pre-encoding device 100 is a place where an arbitrary value is set in anticipation of a key value being changed from the outside at all times. In this case, the pre-encoding device 100 may be used separately from the music half cycle, or may be directly attached to the music half cycle. Reference numeral 102 is a data storage unit for storing the encoder data (Encoded Data) and voice chorus data for tempo conversion and key output from the pre-encoding device 100. Reference numeral 116 denotes a system control unit which outputs a MIDI control signal to the MIDI control unit 118 and outputs a command to be synchronized with the MIDI control signal. 118 denotes a MIDI control unit which converts the MIDI control signal into an analog signal. Output to the output unit 114. Reference numeral 104 denotes a controller that outputs a synchronous control signal in accordance with a command received from the system control unit 116 and outputs a voice chorus request signal in response to a key conversion request command output from the system control unit 116. Reference numeral 106 denotes an MPEG decoder which receives the audio MPEG decoder data from the data storage 102 and stores the audio MPEG decoder data in an internal buffer and outputs the audio MPEG decoder data in the buffer in response to a synchronous control signal from the controller 104. Reference numeral 108 denotes a tempo conversion decoding unit built in the MPEG decoder 106, which receives tempo conversion encoder data from the data storage 102 for tempo conversion and reproduces the converted tempo waveform in real time. Reference numeral 110 is a key conversion decoding unit installed in the MPEG decoder 106 to receive tempo-converted data from the tempo conversion decoding unit for key conversion, synthesize them into key conversion signals, and reproduce them in real time. Finally, reference numeral 112 denotes a D / A converter which converts the digital signal output from the MPEG decoder 106 into an analog signal and outputs the analog signal to the output unit 114. Here, the configuration of the key conversion and tempo conversion pre-encoding device 100 will be described in detail with reference to FIG.

3 is a block diagram of a pre-encoder for storing encoder data for key conversion and tempo conversion in a computer music cycle according to the present invention. The chorus data input unit 120, analysis section classification unit 130, and synthesis section classification are shown in FIG. And a correlation value calculation section 150. That is, the chorus data input unit 120 stores data obtained by sampling the original voice signal corresponding to the converted key value at regular intervals, and the chorus data analysis section classifier 130 is the chorus data input unit. It is a device that creates basic data of tempo conversion by cutting signals input from 120 at regular intervals. The chorus data synthesizing section classifying unit 140 is a device for generating the synthesis section data multiplied by a corresponding ratio according to a predetermined key and tempo variable step for each analysis section data classified by the chorus data analysis section classifying unit 130. The chorus data correlation value calculation unit 150 calculates a maximum correlation value for each synthesis section obtained by the chorus data synthesis section classification unit 140.

Hereinafter, a method of converting a key of a music MIDI and a key of a voice chorus when key conversion is requested during MIDI music playing in the computer music cycle configured as described above will be described in detail.

First, referring to FIG. 3, a method of encoding the operating state of the pre-encoding device 100, that is, the key conversion and the tempo conversion, will be described. A chorus of PCM data sampled at a predetermined interval from the chorus data input unit 120 is described. The data analysis section classification unit 130 cuts the data at regular analysis sections (hereinafter, abbreviated as “S_a”) to generate basic data of tempo conversion. The key conversion is performed by resynthesizing the tempo converted data. Subsequently, the chorus data analysis section classifying unit 140 multiplies the corresponding ratio according to the key (i.e., the key value set in anticipation of changing the key value in the key changing section) for each analysis section “S_a” and the tempo variable step. Create a composite section (abbreviated as "S_s") data. Thereafter, the correlation calculation unit 150 obtains a cross-correlation of the front and rear predetermined sections for each “S_s” obtained by the chorus data synthesis section classification unit 140, and calculates a maximum value. That is, the maximum correlation value (abbreviated as "K" hereinafter) is obtained. At this time, the maximum correlation value "K" is a value for relocating the synthesis section to the point that the synchronization between the intervals when there are two "S_s".

In this case, the above-described process will be described by way of example. In the case where the standard key is to be increased by 1/2 key (semitone), first, “S_s” is obtained from the chorus data analysis section classification unit 120, and then the chorus data synthesis section is performed. The classification unit 140 obtains "S_s" which becomes "S_s / S_a" = 1.06, and then the correlation calculation unit 150 obtains "K". At this time, the "S_s" is divided into intervals longer than "S_a". Here, by rearranging the synthesis section by using the “S_a”, “S_s”, and “K”, the signal having a variable tempo of 106% can be synthesized, and the length of the synthesized signal can be increased by 1/2. The length of the original signal is the same, and the key value is synthesized by the signal as high as 1/2 key. In this case, the process is performed by the tempo transform decoding unit 108 and the key transform decoding unit 110.

Next, an operation process of the tempo conversion decoding unit 108 and the key conversion decoding unit 110 built in the MPEG decoder 106 will be described in detail with reference to FIG. 2. The entire value of the pre-encoding device 100 is always input to the data storage 102. When the key value is input to the MPEG decoder 112 from the outside, a value corresponding to the key value is input from the encoder data stored in the data storage 102. For example, if the key value input from the outside is 4 steps, the encoder data of 4 steps is input to the tempo conversion decoding unit 108. That is, when the system controller 116 issues a key conversion request command to the controller 104, the controller 104 outputs a voice chorus data request signal. Subsequently, the data storage 102 transmits the audio MPEG, the key, and the tempo encoded data to the MPEG decoder 106 in response to the voice chorus data request signal. At this time, the controller 104 transmits a key control signal (Key Control Singal) to the MPEG decoder 106, the MPEG decoder 106 corresponds to the key conversion ratio as a previous step for key conversion to the tempo conversion decoding unit 108 built in the MPEG decoder. The key control signal is transmitted, and the key control signal is transmitted to the key conversion decoding unit 110. Thereafter, the tempo conversion large coding unit 108 determines a tempo conversion request step based on the tempo control signal from the MPEG decoder 106. The tempo-converted signal is read by the MPEG decoder 106 by reading the parameters and data of the tempo in the audio MPEG, key, and tempo encoder data received from the data storage 102 according to the tempo conversion request step identified by the tempo conversion decoding unit 108. First synthesize. Subsequently, the key transform decoding unit 110 receives the first synthesized signal from the tempo transform decoding unit 108 and cuts and synthesizes the signal as proportional to the key variable ratio to generate a second synthesized signal. In this case, the first synthesized signal is a signal whose length conversion is necessary to perform key conversion from the original signal, and the second synthesized signal is cut by a key variable ratio from the length-converted primary synthesized signal. It is a signal that is added or signaled.

After that, the S_s value and the K value (the number of K values is equal to the number of S_s) obtained by the tempo conversion decoding unit 108 are 1 × S_s + K1, 2 × S_s + K2, and 3 × S_s + K3. ,… … The signal is synthesized by the method of. That is, as shown in FIG. 4, through the process of (c), (d) and (e), a synthesized signal having a variable tempo such as (f) is obtained. Next, a signal whose length is shortened or shortened (ie, a synthesized signal having a variable tempo) is not inputted to the key conversion decoding unit 110 by the tempo conversion decoding unit 108. 110 converts the synthesized signal back into a key variable signal. That is, as shown in FIG. 5, the tempo conversion decoding unit 108 converts the original signal (a) into a signal as shown in (b) by varying only the length of the signal without changing the key value. 110 cuts the signal (b) at a constant rate or adds the signal to make the signal length the same as the original signal and converts only the key value to produce a signal as shown in (c).

Here, an operation process of the tempo transform decoding unit 108 and the key transform decoding unit 110 performing the above process will be described as an example.

First, when the key is to be increased, the pre-encoding device 100 outputs the encoder data to the MPEG decoder 106, and the tempo conversion decoding unit 108 converts the key conversion signal input from the controller 104 into the signal of the encoder data. Longer than the original signal). The synthesized signal then becomes longer than the original signal length but the key value does not change. Subsequently, the first synthesized signal is cut and synthesized as much as the proportion of the key variable ratio, wherein the synthesized signal is equal to the original signal length and only the key value is increased. Subsequently, the original signal length is increased by about 6% using the maximum correlation value in the audio MPEG data input from the data storage 102. This creates a first order composite signal with only the length of the signal unchanged. Then, when the primary synthesized signal is cut out by a predetermined ratio (a ratio for increasing the key semitones), the length of the signal becomes the same as the original signal, and only the key value of the signal is increased by 1/2 (half tone).

When the second key is to be lowered, the pre-encoding device 100 first outputs the encoder data to the MPEG decoder 106, and the tempo conversion decoding unit 108 converts the key conversion signal input from the controller 104 into the signal of the encoder data. Shorter than the original signal). The synthesized signal is then shorter than the original signal length but the key value does not change. Subsequently, in the first synthesized signal, the synthesized signal is added in proportion to the key variable ratio, where the synthesized signal is equal to the original signal length and only the key value is lowered. Subsequently, the original signal length is reduced by about 6% using the maximum correlation value in the audio MPEG data input from the data storage 102. This produces a first order composite signal with only the length of the signal reduced without changing the key value. Subsequently, when the primary synthesized signal is added to the signal again by a certain ratio (a ratio for lowering the key halftone), the length of the signal becomes the same as the original signal, and only the key value of the signal is reduced by 1/2 (halftone).

As described above, the computer music half cycle of the present invention can implement the tempo conversion and the key conversion of the voice chorus in real time by utilizing the pre-encoded voice chorus data. In addition, since the key can be simply converted using a tempo-converted signal without attaching a key conversion chip to the MPEG decoder, the cost of the product can be reduced and no noise is generated even when the key is converted. There is this.

Claims (2)

A computer music cycle, comprising: a pre-encoding device for storing encoder data for tempo conversion and key conversion, a data storage for storing the encoder data and voice chorus data, and a key conversion request command output from a system controller A controller for outputting a voice chorus request signal, a data controller for storing the encoder data and voice chorus data, and transmitting key and tempo encoder data in response to the voice chorus request signal, and an audio amplifier decoder from the data storage unit. An MPEG decoder unit for receiving data and storing the data in an internal buffer, and a tempo that is embedded in the MPEG decoder and receives tempo conversion encoder data from the data storage unit for tempo conversion and reproduces the converted tempo waveform in real time. A transform decoding unit, It is built in the pack decoder, and has a key conversion function comprising a key conversion decoding unit for receiving the tempo converted data from the tempo conversion decoding unit for key conversion, synthesized into a key conversion signal and reproduced in real time Computer music class cycle. The apparatus of claim 1, wherein the pre-encoding device comprises: a chorus data input unit for storing data sampled from the original speech signal at regular intervals, and a signal input from the chorus data input apparatus at a predetermined analysis interval to cut out a tempo conversion. Chorus data analysis section classification unit for generating basic data and chorus data analysis section classification unit for generating composite section data by multiplying the corresponding ratio according to the key and tempo variable step for each analysis section data classified by the chorus data analysis section classification unit And a maximum correlation value calculating unit for obtaining a maximum correlation value for each synthesis period obtained by the chorus data synthesis period classification unit.