Audio data processing device, audio data processing method and program

Abstract

Provided is an audio data processing device including a playback unit that plays audio data, a playback direction switching unit that switches between forward playback and reverse playback of the audio data according to an operation signal, and a playback position control unit that moves the playback position of the audio data to a predetermined position when the reverse playback is switched to the forward playback.

Description

[Technical field]

[0001] The present invention relates to an audio data processing device, an audio data processing method, and a program. [Background technology]

[0002] For example, as described in Patent Document 1, a technique is known that presents information for practicing performance in devices such as DJ players and DJ controllers operated by DJs (Disc Jockeys). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2019 / 239486 Summary of the Invention [Problem to be solved by the invention]

[0004] One of the most common techniques used with DJ equipment is scratching, which involves operating the platter to move the playback position of the track forward or backward, while operating the crossfader to mute the track or change the playback volume, but because it requires operating both the platter and the crossfader at the right amount and with the right timing, it can be difficult for beginners to master.

[0005] Therefore, an object of the present invention is to provide an audio data processing device, an audio data processing method, and a program that can effectively assist in practicing scratching on DJ equipment. [Means for solving the problem]

[0006] According to one aspect of the present invention, there is provided an audio data processing device comprising: a playback unit that plays audio data; a playback direction switching unit that switches between forward and reverse playback of the audio data in response to an operation signal; and a playback position control unit that moves the playback position of the audio data to a predetermined position when the reverse playback is switched to the forward playback.

[0007] According to another aspect of the present invention, there is provided an audio data processing method comprising the steps of: playing audio data; switching between forward and reverse playback of the audio data in response to an operation signal; and moving the playback position of the audio data to a predetermined position when the reverse playback is switched to the forward playback.

[0008] According to yet another aspect of the present invention, there is provided a program for causing a computer to realize a function of playing audio data, a function of switching between forward and reverse playback of the audio data in response to an operation signal, and a function of moving the playback position of the audio data to a predetermined position when the reverse playback is switched to the forward playback. [Brief description of the drawings]

[0009] [Figure 1] 1 is a diagram showing the overall configuration of a DJ controller according to one embodiment of the present invention; [Diagram 2] 2 is a block diagram showing a configuration of an audio data processing function of the DJ controller shown in FIG. 1. [Diagram 3] FIG. 3 is a block diagram showing functions that become effective when the practice assistance function is not activated in the DJ controller shown in FIG. 2. [Figure 4] 3 is a block diagram showing functions that become effective when a first practice assistance function is activated in the DJ controller shown in FIG. 2. [Diagram 5] FIG. 13 is a diagram conceptually showing a first practice assistance function. [Figure 6] 6 is a flowchart showing the process in the example of FIG. 5. [Figure 7]13 is a flowchart showing a process in another example of the first practice assistance function. [Figure 8] 3 is a block diagram showing functions that become effective when a second practice assistance function is activated in the DJ controller shown in FIG. 2. FIG. [Figure 9] FIG. 13 is a diagram conceptually showing a second practice assistance function. [Figure 10] 10 is a flowchart showing the process in the example of FIG. 9. [Figure 11] FIG. 3 is a block diagram showing functions that become effective when a third practice assistance function is activated in the DJ controller shown in FIG. 2. [Figure 12] FIG. 13 is a diagram conceptually showing a third practice assistance function. [Figure 13] 13 is a flowchart showing the process in the example of FIG. 12. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In this specification and the drawings, components having substantially the same functional configurations are designated by the same reference numerals, and redundant description will be omitted.

[0011] 1 is a diagram showing the overall configuration of a DJ controller according to an embodiment of the present invention. The DJ controller 100 is an audio data processing device in this embodiment, and plays music using audio data acquired from an external source. At this time, a user can use operators such as platters 101A, 101B, a crossfader 102, performance pads 103A, 103B, an effect adjustment knob 104, an effect start button 105, and channel faders 106A, 106B arranged on the DJ controller 100 to control the playback of audio data and apply various effects to the played audio data.

[0012] In the DJ controller 100 as described above, it is possible to play back the first audio data using the platter 101A, performance pads 103A, and channel fader 106A, etc., and to play back the second audio data using the platter 101B, performance pads 103B, and channel fader 106B, etc., independently of each other. In the following description, the operation and processing system for playing back the first audio data is also referred to as deck A, and the operation and processing system for playing back the second audio data is also referred to as deck B. Meanwhile, the controls also include those that are commonly arranged on deck A and deck B, such as the crossfader 102, effect adjustment knob 104, and effect start button 105.

[0013] Of the controls of the DJ controller 100, the platters 101A, 101B and the crossfader 102 are primarily used for scratching. The platters 101A, 101B are controls for controlling the playback position of the audio data played on the A deck and the B deck, respectively. Specifically, the user can advance the playback position of the audio data by rotating the rotary controls, platters 101A, 101B, clockwise, and can move the playback position of the audio data back to the previous position by rotating them counterclockwise. In scratching, forward and reverse playback of the audio data is repeated by reversing the rotation direction of the platters 101A, 101B.

[0014] On the other hand, the crossfader 102 is an operator for controlling the balance of the playback volume between the first audio data and the second audio data. Specifically, if the crossfader 102 is positioned at the end of the A deck side, the ratio of the playback volume between the A deck and the B deck will be A:B=100:0, and conversely, if it is positioned at the end of the B deck side, the ratio of the playback volume will be A:B=0:100. In scratching, the crossfader 102 is used to mute the deck on which the scratch is to be performed, that is, the playback volume is temporarily set to 0 and the sound is cut off, and this operation is repeated. Note that the DJ controller 100 is configured in the same way as a normal DJ controller with respect to the parts other than the audio data processing function described below, including the platters 101A, 101B and the crossfader 102, and therefore detailed explanations of these parts will be omitted.

[0015] Fig. 2 is a block diagram showing the configuration of the audio data processing function of the DJ controller shown in Fig. 1. In the illustrated example, the audio data processing function 110 of the DJ controller 100 includes a playback unit 111, a playback direction switching unit 112, a playback speed control unit 113, a playback effect selection unit 114, a playback volume control unit 115, a time interval calculation unit 116, a playback position control unit 117, a playback position setting unit 118, and a threshold determination unit 119. Each of these units is implemented by, for example, a CPU (Central Processing Unit) or a DSP (Digital Signal Processor) that operates according to a program stored in a memory. The function of each unit will be further described below.

[0016] The reproducing unit 111 reproduces the audio data of the music. Specifically, the reproducing unit 111 processes the audio data of the music input from a terminal device such as a PC (Personal Computer) or a smartphone connected by a wired or wireless communication means such as a USB (Universal Serial Bus) via an input interface (not shown), or from a removable recording medium such as a USB memory, and outputs the processed data to a speaker or other external device via an output interface (not shown). The reproducing unit 111 determines the reproducing position, reproducing speed, and reproducing volume of the audio data according to the control of a reproducing direction switching unit 112, a reproducing speed control unit 113, a reproducing volume control unit 115, and a reproducing position control unit 117, which will be described later. The reproducing unit 111 also applies various effects to the reproduced audio data according to the control of a reproducing effect selection unit 114. The reproducing unit 111 can reproduce the first audio data and the second audio data, which are respectively loaded into the A deck and the B deck described with reference to FIG. 1, independently of each other, and the above control can also be performed independently for the first audio data and the second audio data.

[0017] The playback direction switching unit 112 switches between forward playback and reverse playback of the audio data played back by the playback unit 111 in response to an operation signal generated by the platter 101. The playback speed control unit 113 controls the playback speed of the audio data played back by the playback unit 111 in response to an operation signal from the platter 101. The platter 101 shown in FIG. 2 corresponds to either the platter 101A or 101B shown in FIG. 1. As described above, the playback unit 111 plays back the audio data of the A deck and the B deck independently of each other, so two playback direction switching units 112 and playback speed control units 113 to which the operation signals of the platters 101A and 101B are input may be implemented, or an operation signal of either the platter 101A or 101B may be selectively input to a single playback direction switching unit 112 and playback speed control unit 113.

[0018] Specifically, the playback direction switching unit 112 controls the playback unit 111 to play back the audio data in the forward direction when the platter 101 is not being operated and is being rotated in a first direction (clockwise), and to play back the audio data in the reverse direction when the platter 101 is being rotated in a second direction (counterclockwise) opposite to the first direction. Here, if a time code is associated with the audio data, the time code increases in forward playback and decreases in reverse playback. In addition, the playback speed control unit 113 controls the playback unit 111 to play back the audio data at a normal speed determined according to, for example, the BPM of a song when the platter 101 is not being operated, and to vary the playback speed according to the rotation speed when the platter 101 is being rotated in either direction by the user's operation. For example, when the platter 101 is rotated in a first direction (clockwise), the playback speed control unit 113 reduces the playback speed below the normal speed if the rotation speed is less than a threshold value (e.g., 33 RPM or 45 RPM), and increases the playback speed above the normal speed if the rotation speed is greater than the threshold value.

[0019] The playback effect selection unit 114 selects a playback effect to be applied to the audio data played by the playback unit 111 according to the playback direction switched by the playback direction switching unit 112. Specifically, the playback effect selection unit 114 applies a first playback effect to the audio data when the audio data is played in the forward direction by the playback direction switching unit 112, and applies a second playback effect to the audio data when the audio data is played in the reverse direction. Here, there are two cases in which the audio data is played in the forward direction: when the platter 101 is not operated and when it is rotated in a first direction (clockwise). When the platter 101 is not operated, the playback effect selection unit 114 may not apply the first playback effect even if the audio data is played in the forward direction. The playback effects applied by the playback effect selection unit 114 include, for example, "no effect", "mute effect", "echo effect" or "filter effect". In the case of "mute effect", the playback effect selection unit 114 controls the playback volume control unit 115 to mute the audio data. In this case, muting means that the playback volume is substantially set to 0. In other cases, the playback effect selection unit 114 controls the playback unit 111 so that effects such as echo and filtering are applied when playing back audio data.

[0020] The playback volume control unit 115 controls the playback volume of the audio data played by the playback unit 111 in response to an operation signal from the crossfader 102. As described above, the crossfader 102 is an operator for controlling the balance of the playback volume between the music (first audio data) on the A deck and the music (second audio data) on the B deck. Therefore, the playback volume control unit 115 cross-fades the playback volume of the audio data being played on each of the A deck and the B deck in response to an operation signal from the crossfader 102. In this case, when viewed from the A deck or the B deck, the playback volume control unit 115 controls the playback volume of the audio data in accordance with the operation of the crossfader 102. Alternatively, when a specific function as described below is activated, the playback volume control unit 115 may control the playback volume of the audio data in accordance with the control of the playback effect selection unit 114 instead of the operation signal from the crossfader 102. Note that the playback volume control section 115 can also control the playback volume by operating, for example, the channel faders 106A, 106B or the master volume, but as the configuration is similar to that of a normal DJ controller, a detailed description will be omitted.

[0021] The time interval calculation unit 116 calculates a time interval during which a predetermined event occurs in the operation signal from the crossfader 102 input to the playback volume control unit 115. Here, the predetermined event is detected, for example, when the crossfader 102 starts moving from the end on the A deck side or the B deck side toward the opposite side. In this case, the event is acquisition of an operation signal that increases the playback volume of the audio data on the A deck or the B deck from 0 or a value close to 0. For example, when the crossfader 102 is implemented by a linear potentiometer, such an event is detected when the output value of the crossfader 102 fluctuates from an upper limit value or a lower limit value, or decreases or increases beyond a predetermined range from the upper limit value or the lower limit value.

[0022] The playback position control unit 117 controls the playback position of the audio data played by the playback unit 111. As described above, since the playback unit 111 plays back the audio data of the A deck and the B deck independently of each other, two playback position control units 117 may be implemented, or a single playback position control unit 117 may selectively control the playback position of the audio data of either the A deck or the B deck. The deck to be controlled may be set by a user operation, or may be automatically set to the deck on which scratching by the platter 101 is being performed, for example. Here, while the above-mentioned playback direction switching unit 112 and playback speed control unit 113 change the playback position as a result of fast-forwarding or rewinding the playback of the audio data in response to the operation of the platter 101, the playback position control unit 117 changes the playback position by, for example, jumping to a position previously set by the playback position setting unit 118.

[0023] Specifically, the playback position control unit 117 moves the playback position of the playback data to a predetermined position if the time interval calculated by the time interval calculation unit 116 exceeds a threshold value, and continues playback without moving the playback position if the time interval does not exceed the threshold value. Alternatively, the playback position control unit 117 changes the playback position of the audio data to a predetermined position when the playback direction switching unit 112 switches from reverse playback to forward playback, and continues playback without moving the playback position in other cases. Note that the playback position control unit 117 can also move the playback position by operating the performance pads 103A and 103B, for example, but the configuration is the same as that of a normal DJ controller, so detailed description will be omitted.

[0024] The playback position setting unit 118 sets the destination of the playback position to be moved by the playback position control unit 117. Specifically, the playback position setting unit 118 sets the destination of the playback position according to a user operation. The destination is set by, for example, a hot cue setting operation using the performance pads 103A and 103B, but is not limited to this example. Meanwhile, the threshold determination unit 119 determines a threshold used by the playback position control unit 117 for determination based on a time interval. The threshold determination unit 119 may determine the threshold according to, for example, the BPM of the backing track. Here, the backing track means the music (second audio data) played on the B deck when scratching is performed on the music (first audio data) played on the A deck. For example, the threshold determination unit 119 may determine a time of 1 / 2 beat, 1 / 3 beat, or 1 / 4 beat calculated from the BPM of the backing track as the threshold.

[0025] 3 is a block diagram showing functions that are enabled when the practice assistance function is not activated in the DJ controller shown in FIG. 2. The functions that are enabled in this case are the playback unit 111, the playback direction switching unit 112, the playback speed control unit 113, and the playback volume control unit 115. In this case, the playback direction and playback speed of the audio data played by the playback unit 111 are controlled by the playback direction switching unit 112 and the playback speed control unit 113 in response to an operation signal from the platter 101. Also, the playback volume of the audio data is set by the playback volume control unit 115 in response to an operation signal from the crossfader 102. In this case, when performing a scratch, the user must rotate the platter 101 at a precise timing and rotation amount to repeat the playback of the audio data in a desired section, while controlling the playback volume including muting by precisely operating the crossfader 102.

[0026] The above two operations are necessary to complete the scratching performance technique. However, as already described, it is not easy for beginners to acquire the two operations simultaneously. Therefore, in the DJ controller according to the present embodiment, the first to third scratch practice functions as described below are provided. Note that only one of the first to third scratch practice functions may be implemented, any two of them may be implemented, or all three of them may be implemented. When a plurality of practice functions are implemented, the functions may be automatically selected and activated, for example, by operating the platter 101 or the crossfader 102, or may be selected and activated by user operations via the effect adjustment knob 104, the effect activation button 105, or the like.

[0027] (First practice assistance function) FIG. 4 is a block diagram showing functions that become effective when the first practice assistance function is activated in the DJ controller shown in FIG. 2. The functions that become effective in this case are the playback unit 111, the playback direction switching unit 112, the playback speed control unit 113, the playback effect selection unit 114, and the playback volume control unit 115, and the operation signal of the crossfader 102 input to the playback volume control unit 115 is invalidated. That is, the playback volume control unit 115 controls the playback volume of the audio data regardless of the control signal from the crossfader 102. In this first practice assistance function, the control of the playback volume using the crossfader 102 is assisted by the playback effect selection unit 114 and the playback volume control unit 115, and the user can concentrate on operating the platter 101.

[0028] FIG. 5 is a diagram conceptually illustrating the first practice assistance function, and FIG. 6 is a flowchart showing the process in the example of FIG. 5. As shown in FIG. 5 as (a), when the user is not operating the platter 101, the platter 101 is not rotating or is rotating in a first direction (clockwise) at a predetermined rotation speed, and no operation signal of the platter is acquired (NO in step S101). In this case, the playback unit 111 plays back the audio data in the forward direction at the normal speed (step S104). As shown in FIG. 5 as (b), when the user rotates the platter 101 in a second direction (counterclockwise), an operation signal of the platter 101 is acquired (YES in step S101), and this operation signal indicates rotation in the second direction (YES in step S102). In this case, the playback direction switching unit 112 plays back the audio data in the reverse direction, but at the same time, the playback effect selection unit 114 applies a "mute effect" to the audio data, and as a result, the playback of the audio data is muted (step S103).

[0029] Furthermore, as shown in FIG. 5 as (c), when the user rotates the platter 101 in the first direction (clockwise), an operation signal of the platter 101 is acquired (YES in step S101), but this operation signal indicates rotation in the first direction (NO in step S102). In this case, the playback direction switching unit 112 plays the audio data forward, and the playback effect selection unit 114 applies "no effect" to the audio data. As a result, the audio data is played forward (step S104). Note that in this case, the playback speed control unit 113 controls the playback speed according to the rotation speed of the platter 101, but this point is not reflected in the flowchart of FIG. 6.

[0030] The above-mentioned functions allow the user to achieve the scratch technique of "muting playback during reverse playback" without having to operate the crossfader 102. Therefore, when practicing scratching, the user can concentrate on operating the platter 101 without worrying about synchronizing the operation with the crossfader 102. Furthermore, because operating the platter 101 changes the playback volume in the same way as if the crossfader 102 had been operated at the ideal timing, the user can effectively practice scratching while enjoying the sound being played back, rather than performing monotonous tasks.

[0031] FIG. 7 is a flowchart showing the process in another example of the first practice assistance function. In this example, different "mute effects" are applied when the platter 101 is rotated in a first direction (clockwise) and when it is rotated in a second direction (counterclockwise). In this embodiment, the "mute effect" includes a "full mute effect" in which sound is continuously muted while the effect is applied, and an "intermittent mute effect" in which sound is muted intermittently at a predetermined cycle. In the case of the intermittent mute effect, multiple effects with different cycles and number of times the sound is muted can be set. In the example shown in FIG. 7, when the platter 101 is rotated in the first direction (clockwise), an intermittent mute effect is applied that mutes the sound up to two times in a cycle of 1 / 4 beat of the music played by the audio data, and when the platter 101 is rotated in the second direction (counterclockwise), an intermittent mute effect is applied that mutes the sound up to three times in a cycle of 1 / 4 beat of the music.

[0032] As a specific process, when the operation signal of the platter is not acquired (NO in step S201), the playback unit 111 plays back the audio data in the forward direction at the normal speed (step S204). At this time, the playback effect selection unit 114 does not apply the intermittent mute effect as described later even in the forward playback. On the other hand, when the operation signal of the platter is acquired (YES in step S201) and the operation signal indicates rotation in the first direction (YES in step S202), the playback direction switching unit 112 plays back the audio data in the forward direction, and the playback effect selection unit 114 applies the first intermittent mute effect, specifically, an effect of muting the sound up to twice at the cycle of 1 / 4 beat of the music (step S203). On the other hand, when the operation signal indicates rotation in the second direction (NO in step S202), the playback direction switching unit 112 plays back the audio data in the reverse direction, and the playback effect selection unit 114 applies the second mute effect, specifically, an effect of muting the sound up to three times at the cycle of 1 / 4 beat of the music (step S205). Note that the fact that the playback speed control unit 113 controls the playback speed according to the rotation speed of the platter 101 is not reflected in the flowchart of FIG. 7 either.

[0033] Similar to the examples of FIGS. 5 and 6, in the example of FIG. 7 above, the mute pattern frequently used in scratching can be realized without operating the cross fader 102. Therefore, the user can concentrate on the operation of the platter 101 and effectively practice scratching while enjoying the reproduced sound.

[0034] In the above example, the first effect applied during forward playback is no effect, and the second effect applied during reverse playback is a full mute effect. In another example, the first effect may be a full mute effect, and the second effect may be no effect. In the latter case, the effect may not be applied in the case of forward playback due to the platter not being operated. In addition, as an example of an effect using an intermittent mute effect, the first effect applied during forward playback may be an intermittent mute effect, and the second effect applied during reverse playback may be a full mute effect. Alternatively, the first effect may be a full mute effect, and the second effect may be an intermittent mute effect. In the case of an intermittent mute effect, the cycle in which the sound is muted may be set to, for example, 1 / 2 beat, 1 / 4 beat, or 1 / 8 beat of the music being played. In addition, the number of times in the case of an intermittent mute effect may be set to, for example, 2 times, 3 times, or 6 times.

[0035] In addition, as an application of the above function that is not limited to the scratch practice assistance, the playback effect selection unit 114 may apply an effect other than the mute effect during forward playback and / or reverse playback, specifically, for example, an echo effect or a filter effect. In this case, the operation signal of the crossfader 102 is not invalidated even when the function is activated, and the playback volume control unit 115 may control the playback volume of the audio data according to the operation signal from the crossfader 102. Such a function is used, for example, when a user who can already perform scratching by operating both the platter 101 and the crossfader 102 performs scratching by adding playback effects to the sound other than mute. Also, for example, such an effect may be applied by superimposing it on the above mute effect even during scratch practice. As a non-limiting example of a combination of playback effects in such a case, the first effect applied to forward playback may be no effect, and the second effect applied to reverse playback may be an echo effect. Also, the first effect may be an echo effect, and the second effect may be a filter effect.

[0036] (Second practice aid function) Fig. 8 is a block diagram showing functions that become active when the second practice assistance function is activated in the DJ controller shown in Fig. 2. In this case, the functions that become active are the playback unit 111, playback volume control unit 115, time interval calculation unit 116, playback position control unit 117, playback position setting unit 118, and threshold determination unit 119, while the functions of the playback direction switching unit 112, playback speed control unit 113, and playback effect selection unit 114 are disabled. In this second practice assistance function, the playback position control unit 117 assists in setting the playback direction and playback speed of audio data using the platter 101, allowing the user to concentrate on operating the crossfader 102.

[0037] FIG. 9 is a diagram conceptually showing the second practice assistance function, and FIG. 10 is a flowchart showing the process in the example of FIG. 9. In the example of FIG. 9, scratching is performed on the music (first audio data) played on the A deck. An operation signal is acquired by sliding the crossfader 102 as shown in FIG. 9 (a) (YES in step S301). In this case, the operation is an operation to set the playback volume of the A deck to 0, not an operation to increase the playback volume from 0 (NO in step S302), so other processes are not executed, and the playback volume control unit 115 controls the playback volume of the audio data played on the A deck in response to the operation signal (step S306). On the other hand, when the crossfader 102 is slid to the end on the A deck side and then returned as shown in FIG. 9 (b), an operation signal for increasing the playback volume of the A deck from 0 is acquired (YES in steps S301 and S302). In this case, the time interval calculation unit 116 calculates the time interval during which this event, that is, the event of increasing the playback volume of deck A from 0, occurred (step S303).

[0038] Here, in the case of (b) of Fig. 9, the time interval t1 from the previous event is long (the previous event is not shown), and exceeds the threshold determined by the threshold determination unit 119, specifically, the time of 1 / 2 beat of the music played on the B deck (YES in step S304). In this case, the playback position control unit 117 moves the playback position of the audio data being played on the A deck to a position previously set by the playback position setting unit 118 (step S305), and the playback volume control unit 115 controls the playback volume of the audio data being played on the A deck in response to the operation signal (step S306). The destination of the playback position in step S305 is previously set by the playback position setting unit 118, for example, by a hot cue setting operation using the performance pads 103A and 103B.

[0039] 9, when the crossfader 102 is once moved away from the end of the A deck side, and then slid back to the end of the A deck side as shown in (c) and (d) in FIG. 9, an operation signal for increasing the playback volume of the A deck from 0 is acquired again (YES in steps S301 and S302). In this case, the time interval t2 from the previous event calculated in step S303 is short and does not exceed the threshold value of 1 / 2 beat of the music played on the B deck (NO in step S304). In this case, the playback continues without moving the playback position of the audio data being played on the A deck, and the playback volume control unit 115 controls the playback volume of the audio data being played on the A deck in response to the operation signal (step S306). Even if similar operations are repeated as shown in (e) and (f) in Figure 9, the time interval t3 does not exceed the threshold value, so playback continues without moving the playback position of the audio data being played on deck A, and the playback volume control unit 115 controls the playback volume of the audio data being played on deck A in response to the operation signal (step S306).

[0040] With the above-mentioned functions, the scratch technique of "muting playback during reverse playback, and then varying the performance with intermittent muting during subsequent forward playback" can be achieved without operating the platter 101. Therefore, when practicing scratching, the user can concentrate on operating the crossfader 102 without being concerned with the timing of operating the platter 101 or the amount of rotation. Furthermore, because operating the crossfader 102 changes the playback position in the same way as if the platter 101 had been operated with the ideal timing and amount of rotation, the user can effectively practice scratching while enjoying the sound being played back, rather than performing monotonous tasks.

[0041] (Third practice aid function) FIG. 11 is a block diagram showing functions that become effective when the third practice assistance function is activated in the DJ controller shown in FIG. 2. In this case, the functions that become effective are the playback unit 111, the playback direction switching unit 112, the playback speed control unit 113, the playback volume control unit 115, the playback position control unit 117, and the playback position setting unit 118, and the functions of the playback effect selection unit 114, the time interval calculation unit 116, and the threshold determination unit 119 are disabled. Note that, for example, when the playback effect selection unit 114 applies an effect other than the mute effect, this may be enabled in combination with the first practice assistance function. In this third practice assistance function, when practicing scratching by operating both the platter 101 and the crossfader 102, the playback position control unit 117 assists the user in cueing the playback position by the platter 101, and the user can concentrate on practicing matching the operation timing of the platter 101 and the crossfader 102.

[0042] FIG. 12 is a diagram conceptually illustrating the third practice assistance function, and FIG. 13 is a flowchart showing the process in the example of FIG. 12. As shown in FIG. 12 (a) and (d), when the user is not operating the platter 101, the platter 101 is not rotating or is rotating in a first direction (clockwise) at a predetermined rotation speed, and no operation signal of the platter is acquired (NO in step S401). In this case, the playback unit 111 plays back the audio data in the forward direction at the normal speed (step S403). On the other hand, as shown in FIG. 12 (b) and (c), when the user rotates the platter 101 in the second direction (counterclockwise) or the first direction (clockwise), an operation signal of the platter 101 is acquired (YES in step S401), and under the control of the playback direction switching unit 112 and the playback speed control unit 113, the playback unit 111 plays back the audio data in the reverse direction or forward direction at a playback speed according to the rotation speed of the platter 101 (step S402).

[0043] In addition, in this function, in each of the above cases, it is determined whether the playback direction has switched from reverse playback to forward playback (step S404). In the example of FIG. 12, when the platter 101 is rotated in the second direction as in (b) and audio data is being played back in the reverse direction, the playback direction of the audio data is switched from reverse playback to forward playback (YES in step S404) when the platter 101 is rotated in the first direction as in (c) and when the user's hand is released and the state returns to no operation as in (d), the playback direction of the audio data is switched from reverse playback to forward playback (YES in step S404). In this case, the playback position control unit 117 moves the playback position of the audio data to a position previously set by the playback position setting unit 118 (step S405), and the audio data is played back in the forward direction at the playback speed determined in the above step S402 or step S403. On the other hand, in other cases (NO in step S404), the playback position is not moved, and the audio data is played back in the forward direction or in the reverse direction at the playback speed determined in step S402 or step S403. The destination of the playback position to be moved in step S405 is set in advance by the playback position setting section 118, for example, by a hot cue setting operation using the performance pads 103A and 103B.

[0044] With the functions as described above, even when the amount of rotation when the platter 101 is rotated in the second direction is too much or too little, the playback of the audio data starts from an appropriate position during subsequent forward playback. Specifically, when the platter has to be rotated 90° to return to the appropriate playback position, even if the platter is rotated only 60°, the forward playback starts from the playback position that has been returned by 90°. Ultimately, it is necessary to be able to accurately cue such a piece of music by operating the platter 101. However, in the previous stage of practice, with the above functions, one can concentrate on matching the operation timing with the cross fader 102 without worrying about the deviation of the rotation amount of the platter 101, and can effectively practice scratching.

[0045] Note that as an application not limited to assisting in scratching practice of the above functions, the playback position control unit 117 may be used in a performance technique called beat juggling in which the audio data of the same piece of music is loaded into both the A deck and the B deck and the platters 101A and 101B are alternately operated. In this case, the playback direction switching unit 112 switches between forward playback and reverse playback of the first audio data played back on the A deck according to the operation signal generated by the platter 101A, while switching between forward playback and reverse playback of the second audio data played back on the B deck according to the operation signal generated by the platter 101B. Further, when the reverse playback of the first audio data played back on the A deck is switched to forward playback, the playback position control unit 117 moves the playback position of the first audio data to a preset first position, and when the reverse playback of the second audio data played back on the B deck is switched to forward playback, the playback position control unit 117 moves the playback position of the second audio data to a preset second position. Thereby, it is possible to support the accurate cueing of the music required in beat juggling.

[0046] In the above case, instead of unconditionally moving the playback position when reverse playback is switched to forward playback, the playback position may be moved, for example, when the difference between the playback position at the end of reverse playback and a preset destination playback position is within a predetermined range. Also, a plurality of destination playback positions may be preset, and the destination playback position closest to the playback position at the end of reverse playback may be automatically selected.

[0047] The embodiment of the present invention described above is illustrative and various modifications are possible. For example, in the above embodiment, a DJ controller is exemplified as an audio data processing device, but similar functions can be implemented in other DJ devices such as a mixer or an all-in-one DJ system (digital audio player with communication and mixing functions). The above functions can also be implemented by a DJ application in a terminal device such as a PC or smartphone. In these cases, the audio data processing device itself does not necessarily have to be provided with an operator such as a platter or crossfader, and an operation signal may be received from an operator provided in an external device such as a turntable of a DVS (Digital Vinyl System). The above functions may be at least partially implemented in a server that transmits audio data to a terminal device via a network, and this server may function as an audio data processing device.

[0048] Although the preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, the present invention is not limited to these examples. It is clear that a person skilled in the art in the technical field to which the present invention pertains can come up with various modified or altered examples within the scope of the technical ideas described in the claims, and it is understood that these also naturally fall within the technical scope of the present invention. [Explanation of symbols]

[0049] 100...DJ controller, 101, 101A, 101B...platter, 102...crossfader, 103A, 103B...performance pad, 104...effect adjustment knob, 105...effect start button, 106A, 106B...channel fader, 110...audio data processing function, 111...playback section, 112...playback direction switching section, 113...playback speed control section, 114...playback effect selection section, 115...playback volume control section, 116...time interval calculation section, 117...playback position control section, 118...playback position setting section, 119...threshold determination section.

Claims

1. a playback unit that plays back audio data; a playback direction switching unit that switches between forward playback and reverse playback of the audio data in response to an operation signal; a playback position control unit that moves a playback position of the audio data to a predetermined position when the reverse playback is switched to the forward playback; An audio data processing device comprising:

2. The operation signal is generated by a rotary operator, 2. The audio data processing device according to claim 1, wherein the playback direction switching unit plays the audio data in a forward direction when the rotary operator is not operated and is rotated in a first direction, and plays the audio data in a reverse direction when the rotary operator is rotated in a second direction opposite to the first direction.

3. 3. The audio data processing device according to claim 2, further comprising a playback speed control unit which plays back the audio data at a normal speed when the rotary operator is not operated, and changes the playback speed of the audio data in accordance with the rotation speed of the rotary operator when the rotary operator is rotated in the first direction or the second direction.

4. The audio data processing device according to claim 1 , further comprising a playback position setting unit that sets the predetermined position.

5. the reproduction unit reproduces the first audio data and the second audio data independently of each other; the playback direction switching unit switches between forward playback and reverse playback of the first audio data in response to an operation signal generated by a first rotary operator, and switches between forward playback and reverse playback of the second audio data in response to an operation signal generated by a second rotary operator; 5. The audio data processing device according to claim 1, wherein the playback position control unit moves the playback position of the first audio data to a first position when reverse playback is switched to forward playback for the first audio data, and moves the playback position of the second audio data to a second position when reverse playback is switched to forward playback for the second audio data.

6. playing audio data; switching between forward playback and reverse playback of the audio data in response to an operation signal; moving a playback position of the audio data to a predetermined position when the reverse playback is switched to the forward playback; A method for processing audio data comprising the steps of:

7. A function for playing audio data; A function of switching between forward playback and reverse playback of the audio data in response to an operation signal; a function of moving a playback position of the audio data to a predetermined position when the reverse playback is switched to the forward playback; A program to make the above happen on a computer.

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