WO2006104164A1

WO2006104164A1 - Audio signal reproducer

Info

Publication number: WO2006104164A1
Application number: PCT/JP2006/306344
Authority: WO
Inventors: Katsuhiko Goda; Yoshiyuki Kakuta
Original assignee: Pioneer Corporation
Priority date: 2005-03-28
Filing date: 2006-03-28
Publication date: 2006-10-05
Also published as: JP4348391B2; JPWO2006104164A1

Abstract

An audio signal reproducer is used for reproducing an audio signal recorded on a recording medium such as an optical disk and preferable used as, especially, a DJ device. The reproduction time of one musical composition composed of an audio signal is acquired from, e.g., a recording medium. The number of beats per unit time such as the BPM is detected from the audio signal. The progress of the reproduction of the audio signal is displayed by using the number of beats according to the reproduction time of one musical composition and the number of beat per unit time. Disk jockeys handling DJ devices frequently grasp the signals of musical compositions with reference to the BPM or the number of beats. Therefore, they can sensuously grasp the progress of the reproduction of a musical composition by viewing the displayed number of beats.

Description

Specification

Audio signal playback device

Technical field

[0001] The present invention relates to a method for displaying a current playback progress status of a music being played in an audio signal playback device.

Background art

[0002] In stores and facilities called discos and clubs, V, a so-called disc jockey (DJ) plays dance music using playback devices for CDs, MDs and other recording media. An audio signal playback device used by a disc jockey is also called a DJ device, and examples thereof are described in Patent Documents 1 and 2.

Patent Document 1: Japanese Patent Application Laid-Open No. 2002-341888

Patent Document 2: Japanese Patent Laid-Open No. 2002-352569

[0004] In the above audio signal playback apparatus, during playback of a music piece, the current playback time is displayed in terms of hours, minutes, seconds, and the number of frames. However, disc jockeys and others who are in a position to play music often grasp the flow of time during performance in terms of musical constituent units such as beats. Therefore, the playback time display in hours, minutes, seconds, etc. has a problem that it is difficult to grasp the progress of the song sensuously!

Disclosure of the invention

Problems to be solved by the invention

[0005] Examples of the problems to be solved by the present invention include the above. It is an object of the present invention to provide an audio signal reproduction device capable of displaying a reproduction state that is easy to understand by displaying a musical reproduction unit in a musical constituent unit.

Means for solving the problem

In a preferred embodiment of the present invention, the audio signal reproduction device detects reproduction time acquisition means for acquiring the reproduction time of one music piece of the audio signal, and detects the number of beats per unit time of the audio signal. Detecting means for reproducing, reproducing means for reproducing the audio signal, Display means for displaying the progress of reproduction of the audio signal using the number of beats based on the reproduction time of one piece of music and the number of beats per unit time.

[0007] The audio signal reproducing device described above can be used when reproducing an audio signal recorded on a recording medium such as an optical disk, and is particularly preferably used as a DJ device or the like. The playback time of one song composed of audio signals is obtained from, for example, a recording medium. Further, the number of beats per unit time such as BPM (Beat Per Minute) is detected from the audio signal. Then, based on the playback time of one song and the number of beats per unit time, the progress of the audio signal playback is displayed using the number of beats. Disc jockeys that handle DJ equipment often know the progress of a song and the current playback position based on BPM and beats, so using the beats makes sense of the progress of song playback. It can be displayed easily.

[0008] In one aspect of the above audio signal reproduction device, the display means displays the number of measures and the number of beats from the beginning of the music as the progress status. In another aspect, the display means displays the number of remaining bars and beats until the end of the music as the progress status. As a result, the operator can easily know the current position in the entire song and the timing of beats in that measure.

[0009] In a preferred example, the display means can display the number of measures and the number of beats as numbers. In another preferred example, the display means indicates the number of bars and the number of beats by a two-dimensional graph, and the graph indicates the number of bars in the horizontal direction and the number of beats in the vertical direction. Can do.

[0010] In another aspect of the audio signal reproduction device, the detection unit repeatedly detects the number of beats per unit time based on the audio signal, and the display unit includes the music piece For each song, the progress status is displayed based on the average number of beats detected per unit time. As a result, the number of beats per unit time can be accurately detected in a song or the like in which the number of beats per unit time is small, and accurate display is possible.

[0011] In another aspect of the audio signal reproduction device, the detection unit repeatedly detects the number of beats per unit time based on the audio signal, and the display unit Displays the progress based on the average value of the number of beats per unit time detected within a predetermined time. As a result, for songs with many fluctuations in the number of beats per unit time, the number of beats per unit time at the current playback position can be detected accurately, and accurate display is possible.

Brief Description of Drawings

FIG. 1 is a plan view showing an appearance of an operation panel of a CD player according to an embodiment.

[Fig. 2] A first example of playback progress is shown.

FIG. 3 shows a first display example of the playback progress status.

FIG. 4 shows a second display example of the playback progress status.

FIG. 5 shows a second display example of the playback progress status.

FIG. 6 is a block diagram showing the internal configuration of the CD player.

FIG. 7 is a flowchart of playback progress status display processing.

Explanation of symbols

[0013] 1 disc

2 Display section

3 Turntable

6 Operation unit

21 BPM detector

22 Noffer memory

23 Address controller

30 System controller

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

[0015] [Appearance of CD player]

FIG. 1 is a plan view of an operation panel of a CD player which is an embodiment of the audio signal reproducing apparatus of the present invention. The CD player 100 accommodates a CD therein and is operated by an operator such as a disc jockey to play music. On the operation panel of the CD player 100, a display unit 2, a turntable 3, and an operation unit 6 are provided. Na Note that a CD player normally used by a disc jockey has various functions, and is provided with a number of operation buttons for that purpose. FIG. 1 shows only those particularly related to the present invention.

[0016] The display unit 2 is composed of, for example, a liquid crystal panel, and displays information such as the number of tracks of the music being played back and the current playback progress status. Note that the present invention is characterized by a technique for displaying the progress of music playback on the display unit 2, and the details thereof will be described later.

[0017] The turntable 3 is manually operated by an operator and has a function of moving the music playback position. In FIG. 1, when the operator rotates the turntable 3 clockwise, the music playback position is advanced, and when the operator rotates counterclockwise, the music playback position is returned.

[0018] The operation unit 6 is operated when jumping the playback position, and includes a forward jump button 6a, a backward jump button 6b, and a jump beat number button 6c. When the operator operates the forward jump button 6a, the music playback position moves forward by a predetermined amount of movement, and when the operator operates the rear jump button 6b, the music playback position moves backward by a predetermined amount of movement. The jump beat number button 6c determines the amount of movement of the playback position by jumping, and the playback position moves by an amount equivalent to the product of the amount indicated by the jump beat button and the number of beats of the song being played. . For example, as shown in Fig. 1, when the operator presses the forward jump button 6a while the jump beat number button 6c indicates the jump beat number "3", the music playback position is 3 beats from the current playback position. Move forward.

[0019] [Display playback progress]

Next, a method of displaying the playback progress status on the display unit 2 will be described. Conventionally, as a method of displaying the playback progress of music, a method of displaying the playback time is generally used. Specifically, there are many that display the current playback time of the music being played in terms of hours, minutes, seconds, and the number of frames. However, in the case of a DJ device used by a disc jockey or the like as in the present embodiment, the operator often grasps the flow of time during the playback of the music on the basis of the beat instead of the hour, minute, second. . For this reason, when the playback time is displayed in hours, minutes and seconds, the progress of playback of the music is often difficult to understand sensuously for disc jockeys and the like. [0020] Therefore, in the present invention, the progress of the music being played is displayed using musical constituent units, specifically, beats and measures. Disc jockeys and others often grasp the temporal flow of music from the number of beats per unit time (for example, BPM), etc., so by displaying the progress of playback using beat measures, you can check the progress. It becomes possible to grasp more intuitively.

[0021] Next, a method for calculating the number of measures and the number of beats used for displaying the progress of the music playback will be described. In DJ equipment, BPM can be detected based on the audio data to be played. Therefore, by detecting BPM, the number of beats per unit time (1 minute) can be detected for each song. Note that the BPM of a song can basically be considered constant throughout the song.

On the other hand, the playback time of a certain piece of music is known. For example, if the audio signal is stored on a recording medium such as a CD, the playback time of each song is recorded on the disk as TOC (Table Of Contents) information, and the recording medium power obtains the playback time of each song. be able to. Therefore, based on the BPM value and the playback time of the music, it is possible to calculate how much the music is composed. In addition, since it is known for each song how many bars are composed of each measure, it can be calculated by calculating how many beats of which measure a certain measure corresponds to.

[0023] Now, assume that a certain song has a BPM of "X", a playback time of "Y" seconds, and a measure of η beats. In this case, the total number of beats “Ζ” in this song is

Ζ = Χ / 60 · Υ (Formula 1)

It is obtained by. The “m” beat from the beginning of the song belongs to the (mZn) th measure from the beginning of the song. In this way, during playback of the music, it is possible to calculate and display the force corresponding to the current beat and the beat of which measure.

[0024] Note that the value of BPM used for the above calculation can be determined by various methods. Normally, BPM is repeatedly detected during song playback. Therefore, if there is time to scan the entire song prior to actual playback, the average of multiple BPM values obtained based on the audio signal of the entire song is calculated, and based on that value. The number of bars and the number of beats can be calculated. This method is suitable for songs with little fluctuation in rhythm and tone. This is particularly effective in that accurate BPM can be used. On the other hand, the number of measures and the number of beats may be calculated using the average value of the latest several BPM values obtained during the playback of the song. This method is effective in that it can obtain the BPM of the current song with high accuracy and use it for songs with a lot of fluctuations in rhythm and tone.

[0025] Next, an example of displaying the progress of music playback by the number of measures and the number of beats will be described. The following display examples are examples in which the number of measures and the number of beats are displayed on the display unit 2 shown in FIG.

[0026] (First display example)

Figure 2 (a) shows one display example of the number of measures and the number of beats. The display unit 2 is provided with a measure display unit 51 and a beat display unit 52. Fig. 2 (a) shows an example of displaying the first part of the song. The starting power of the song, the number of measures up to the current playback position, and the number of beats in the current measure are displayed sequentially. Specifically, the measure number display section 51 displays the number of measures from the beginning of the song as a number. In the beat number display section 52, the number of beats in the measure (number of beats) is displayed numerically. Figure 2 (a) is an example of a song that consists of 4 bars per bar. As the time passes, the number of bars displayed in the bar number display area 51 increases to 1, 2, and-. 1 to 4 are displayed in order on the beat number display section 52.

[0027] Fig. 2 (b) shows an example in which the starting power of the song, the number of measures up to the current playback position, and the number of beats in the current measure are displayed. This is an example. Therefore, the number of bars is increased by 1 at 8 mm, and the number of beats is repeatedly changed from 1 to 8.

[0028] FIG. 3 (a) is an example in which the remaining amount from the current playback position to the end of the song is displayed, and is an example in the case of 1 bar S4. This example is a display example near the end of the song. The measure number display section 51 displays the remaining number of measures, and the beat number display section 52 displays the remaining number of beats in the measure.

[0029] Fig. 3 (b) is an example in which the remaining amount from the current playback position to the end of the song is displayed in the same manner, and is an example in which one measure is composed of 8 mm. The measure number display section 51 displays the remaining number of measures, and the beat number display section 52 displays the remaining number of beats in the measure.

In this way, by displaying the number of bars, the operator can know how many bars the current position is at the beginning of the music or how many bars remain until the end of the music. Also beat By displaying the number, it is possible to know how many beats the current measure has or how many beats remain. Therefore, a disc jockey or the like can easily and intuitively grasp the current playback position in the entire song.

In the examples of FIGS. 2 and 3, when the horizontal width of the beat number display section 52 in the force display section 2 displayed by shifting the beat number in the horizontal direction is small, the measure number display section 51 As with, it is also possible to display the beat number at the same position.

[0032] (Second display example)

Next, a second display example of the number of measures and the number of beats will be described. In the first display example above, the number of bars and the number of beats are displayed numerically. In contrast, in the second display example, the number of measures and the number of beats are displayed in a graph.

FIG. 4 shows an example of displaying the number of measures and the number of beats up to the present power of the music. In Fig. 4, the upper graph 54 shows the sound level of the music, and the higher the black bar extends, the higher the sound level of the music. The lower graph 56 is a graph showing the current playback position. The number of bars is shown in the horizontal direction and the number of beats is shown in the vertical direction. In Fig. 4, the shaded area indicates bars that have already been played. In the example shown in Fig. 4, the current playback position is “3rd beat of measure 22” from the beginning of the song.

FIG. 5 is an example in which the remaining bar number and beat number are displayed from the current playback position. The shaded area indicates the number of remaining bars and beats. In the example shown in Fig. 5, the 2nd beat of measure 22 is calculated from the end of the song.

[0035] As described above, when the number of measures and the number of beats indicating the current reproduction position are indicated by a two-dimensional graph, it becomes easier to understand the current reproduction position. Furthermore, if all measures of a song are displayed in the horizontal direction of graph 56, it becomes easier to grasp the playback position in that song more intuitively.

[0036] [Internal structure of CD player]

Fig. 6 shows the internal structure of the CD player 100. In FIG. 6, a CD player 100 includes a spindle motor 14 that rotates an optical disc 1 in a predetermined direction, and a pickup 15 that optically reads data recorded on the optical disc 1 and outputs a read signal obtained. In addition, the CD player 100 moves the pickup 15 in the radial direction of the optical disc 1. A servo mechanism 16 is provided which performs servo control so as to perform appropriate optical reading while moving backward.

In addition, the CD player 100 includes an RF amplifier unit 17 and a pickup servo circuit 18. The RF amplifier unit 17 also generates an error signal such as a focus error signal FE and a tracking error signal TE as the read signal power output from the pickup 15. The pickup servo circuit 18 performs feedback control of the servo mechanism 16 based on the focus error signal FE and the tracking error signal TE that suppress the occurrence of errors such as a focus error and a tracking error.

[0038] The pickup servo circuit 18 controls the operation of the servo mechanism 16 that moves the pickup 15 to the recording track of the optical disc 1 instructed by the system controller 30.

The RF amplifier unit 17 generates data recorded on the optical disc 1 from the read signal output from the pickup 15 as an RF signal DRF, and supplies it to the decoding unit 19.

[0040] The decoding unit 19 decodes the RF signal DRF in accordance with the format specified for each optical disc 1, and is included in the RF signal DRF! /, The audio stream DAU and the control data. Separate and extract Dc. The decoding unit 19 decodes the audio stream DAU and supplies the decoded audio stream DAU to the BPM detection unit 21 and the buffer memory 22, and also supplies the control data Dc to the system controller 30.

[0041] Here, various control data such as synchronization data and subcode data recorded together with the audio stream DAU are separated and extracted as the control data Dc. The subcode data DSB is supplied from the decoding unit 19 to the BPM detection unit 21 and the buffer memory 22 in synchronization with the audio stream DAU.

[0042] By supplying the synchronization data from the decoding unit 19 to the spindle servo circuit 20, the spindle servo circuit 20 detects an error in the synchronization data with respect to the rotation speed of the spindle motor 14 instructed by the system controller 30. Feedback control of the rotation of the spindle motor 14 is performed to suppress the occurrence of errors.

[0043] The BPM detector 21 measures the BPM based on the audio stream DAU supplied from the decoder 19. The BPM detection unit 21 generates the audio stream DAU in the low and middle frequencies. And a band filter that divides the audio data into three high frequency bands, a level detector that detects the level of audio data for each band, and a level detection signal output from the level detector, A peak detector for detecting the peak level of the audio data for each band. Then, the BPM detection unit 21 obtains an interval between peaks that are temporally continuous based on the peak level of the detected audio data for each band. Assuming that the detected peak level corresponds to the beat position of the song, the BPM can be calculated based on the peak interval. Actually, the peak interval is detected over a predetermined time, and the detected peak interval value is statistically processed to calculate the BPM. The above-mentioned BPM detection method is an example, and various BPM detection methods can be used in the present invention. For example, instead of or in addition to the automatic detection method as described above, the BPM may be detected by detecting the timing at which the operator hits a tap button provided on the operation panel of the CD player 100. A detailed example of the BPM detection method is described, for example, in JP-A-8-201542.

[0044] The buffer memory 22 is a ring memory formed of a large capacity (for example, 64 Mbytes) of SRAM or the like. The audio stream DAU and the subcode data DSB supplied in synchronization are set as a set of package data. The data is sequentially stored in the write address AD RW set by the address controller 23.

[0045] The sub-code data DSB force included in the control data Dc is detected by the system controller 30 and the elapsed track time is detected, and the address control signal SADR is supplied to the address controller 23 every time the elapsed track time changes. By doing so, the address controller 23 sets the above write address ADRW.

[0046] The buffer memory 22 stores the package data composed of the audio stream DAU and the subcode data DSB, and when the read address A DRR is set from the address controller 23, the set read address ADRR Outputs the stored package data and outputs the original audio stream DAU and subcode data DSB separately. Then, the buffer memory 22 supplies the audio stream DAU to the audio signal generation unit 26 and supplies the subcode data DSB to the reproduction time detection unit 24.

[0047] The system controller 30 generates the reproduction time data DT output from the reproduction time detection unit 24. Based on M, a read address ADRR to be set is determined, and an address control signal SAD R is supplied to the address controller 23. In response to this, the address controller 23 sets the read address ADRR.

[0048] The reproduction time detection unit 24 detects the elapsed track time corresponding to the audio stream DU being processed by the audio signal generation unit 26 by examining the contents of the subcode data DSB supplied from the nother memory 22. The detection result is supplied to the system controller 30 as reproduction time data DTM.

Therefore, as described above, the system controller 30 acquires the elapsed time track of the reproduction time data DTM force and instructs the address controller 23 by the address control signal SADR. As a result, the address controller 23 sets the read address AD RR of the pack data to be read from the buffer memory 22 so that discontinuous reproduction sound does not occur.

[0050] The audio signal generation unit 26 decodes the audio stream DAU supplied from the nother memory 22, and outputs the audio data generated by the decoding to the digital output terminal as the digital data. Alternatively, the audio signal generation unit 26 converts the audio data into a stereo audio signal in the audio frequency band by a DZA converter (not shown) and outputs it to the analog output terminal. By connecting the speaker output to the analog output terminal, the music data recorded on the optical disk can be played back as sound.

[0051] The system controller 30 includes a microprocessor (MPU), and controls the entire operation of the CD player 100 by executing a system program that is preset!

Further, the display unit 2 and the operation unit 6 are connected to the system controller 30, and further, an angular velocity detection unit 31 that detects a rotation direction and a rotation speed (angular velocity) of the turntable 3 is connected. .

The angular velocity detection unit 31 optically detects the rotation direction and rotation speed of the turntable 3 using a rotary encoder circuit (not shown), and supplies the detection data S Θ to the system controller 30. As a result, the system controller 30 is operated by the user or the like. Recognize the amount of operation (rotation direction and angular velocity) of the turntable 3. Then, the system controller 30 instructs the address controller 23 by the address control signal SADR to set the read address ADRR corresponding to the operation amount of the turntable 3.

That is, when the system controller 30 examines the detection data S Θ and determines that the turntable 3 is not rotated, the system controller 30 reads out to be set based on the reproduction time data DTM supplied from the reproduction time detection unit 24. Command address ADRR. If it is determined that the turntable 3 has been rotated, the read address ADRR to be set is commanded according to the amount of rotation of the turntable 3 for which the detected data S Θ force is also obtained.

[0055] [Playback progress display processing]

Next, the playback progress display process will be described with reference to FIG. FIG. 7 is a flowchart of the playback progress status display process. The processing described below is realized by the system controller 30 shown in FIG. 6 controlling each component such as the address controller 23. In the following reproduction processing, as shown in FIG. 6, the audio data recorded on the disc 1 is stored in the buffer memory 22 and then read out and reproduced. Therefore, the playback position on the disc 1 is defined by the elapsed track time of the audio data stored in the nother memory 22 and the address on the buffer memory 22.

[0056] First, when the disc 1 is set in the CD player 100, the CD player 100 reads the TOC information of the disc 1 and obtains the playback time of each song (step S10). Thereafter, when playback of a certain song is started, the BPM detector 21 detects BPM (step Sl l). The detected BPM value is always stored in a memory (not shown) in the system controller 30.

Next, the system controller 30 calculates the total number of beats of the music piece based on the above equation 1 (step S12). Further, the system controller 30 acquires the current playback position (ie, elapsed track time) from the playback time data DTM, calculates the current number of measures and beats (step S 13), and displays it (step S 14). .

[0058] Thereafter, when the operator inputs an instruction to end the reproduction of the song, or when the reproduction of the song ends (step S15; Yes), the process ends. While the song has not finished playing Steps SI 1 to 15 are repeated, and the number of bars and the number of beats indicating the current position are displayed on the display unit 2 by the method as in the display example described above.

[0059] In the above embodiment, the power of the present invention applied to a CD player. The present invention can also be applied to a playback device such as a recording medium other than a CD, such as a DVD, or a memory. It is.

Industrial applicability

The present invention can be used for a playback device that plays back an audio signal stored in a recording medium such as a CD or a DVD or a memory.

Claims

The scope of the claims

[1] Music signal of the audio signal Playback time acquisition means for acquiring the playback time of one song,

Detecting means for detecting the number of beats per unit time of the audio signal; and reproducing means for reproducing the audio signal;

Audio comprising: display means for displaying the progress of reproduction of the audio signal using the number of beats based on the reproduction time of one piece of music and the number of beats per unit time. Signal reproduction device.

2. The audio signal reproducing apparatus according to claim 1, wherein the display means displays the number of measures and the number of beats from the beginning of the music as the progress status.

3. The audio signal reproducing apparatus according to claim 1, wherein the display means displays the remaining number of bars and beats until the end of the music as the progress status.

[4] The audio signal reproduction device according to item 2 of the claim, wherein the display means displays the number of bars and the number of beats as numbers.

[5] The display means indicates the number of bars and the number of beats by a two-dimensional graph,

3. The audio signal reproduction device according to claim 2, wherein the graph shows the number of bars in the horizontal direction and the number of beats in the vertical direction.

[6] The detection means repeatedly detects the number of beats per unit time based on the audio signal,

The audio signal according to claim 1, wherein the display means displays the progress based on an average value of a plurality of beats per unit time detected for the music piece. Playback device.

[7] The detection means repeatedly detects the number of beats per unit time based on the audio signal,

2. The audio signal reproduction device according to claim 1, wherein the display means displays the progress based on an average value of the number of beats per unit time detected within a predetermined time. .