Audio device, program, and audio playback method

Abstract

To provide audio reproduction technology capable of reproducing audio data of high sound quality such as high resolution audio with sound quality suitable for BGM.SOLUTION: A main control unit 18 sets an operation mode of a wireless audio system player 1 to a normal mode or a BGM mode. When the operation mode of the wireless audio player 1 is set to the BGM mode, an effect processing unit 16 performs effect processing including at least one of dynamic range compression, high / low frequency cut, distortion addition, petit-noise addition and reproduction pitch change to an audio signal being a reproduction signal of audio data which is a reproduction object, which is inputted from an audio reproduction unit 12 via a mode switch unit 17 on the basis of music information of audio data of the reproduction object, which is informed from a music information acquisition unit 14, and outputs music from a speaker unit 13.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an audio reproduction technique, and more particularly to an audio reproduction technique suitable for reproducing background music (BGM). [Background technology]

[0002] Conventionally, audio devices that acquire, play, and output audio data of music from a media server via a wireless network such as a wireless LAN (Local Area Network) or Bluetooth (registered trademark) are known (see, for example, Patent Document 1). In recent years, with the widening of the bandwidth of wireless networks, the audio data distributed by media servers has become higher in quality, and audio devices of this type that support high-resolution audio data, for example, so-called high-resolution audio, are becoming more common. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] U.S. Patent No. 7,987,294 Summary of the Invention [Problem to be solved by the invention]

[0004] By the way, playing high-quality audio data as background music while working (work, studying, etc.) or going to sleep can actually be disruptive. In particular, playing high-quality audio data of digitally remastered old songs (so-called nostalgic tunes) can be so engrossing that it can be difficult to concentrate on work or to fall asleep.

[0005] Furthermore, high-quality audio data of specific genres, such as classical music, generally has a wide dynamic range, making it difficult to adjust the volume to an appropriate level for background music while working or sleeping. When playing high-quality audio data with a wide dynamic range, if the volume is reduced to prevent high-sound-pressure signals from interfering with work or sleep, low-sound-pressure signals become inaudible, resulting in interruptions in the sound. These interruptions can be unpleasant for the user and disrupt their work or sleep.

[0006] The present invention has been made in consideration of the above circumstances, and its purpose is to provide an audio playback technology that can play back high-quality audio data, such as high-resolution audio, with sound quality suitable for background music. [Means for solving the problem]

[0007] To solve the above problems, in the present invention, in BGM mode, effect processing including at least one of dynamic range compression, high and low frequency cut, distortion addition, pop noise (click noise) addition, and playback pitch change is performed on the audio data to be played back based on the analysis results of the music information or melody of the audio data to be played back, and the effect-processed audio data is then played back and output.

[0008] For example, the present invention provides An audio device that reproduces and outputs audio data, a mode setting means for setting the operation mode to a normal mode or a BGM (Background Music) mode; When the BGM mode is set by the mode setting means, the audio data to be reproduced is subjected to a music information or analysis result of the audio data to be reproduced. Apply , dynamic range compression, high and low frequency cut, distortion addition, crackle noise addition, and playback pitch change. choosean effect processing means for performing the effect; a sound quality analysis means for analyzing the sound quality of the audio data to be reproduced, The effect processing means The necessity of effect processing to be applied to the audio data to be reproduced, which is selected based on the song information or analysis result of the audio data to be reproduced, is changed based on the sound quality analyzed by the sound quality analysis means. . [Effects of the Invention]

[0009] In the present invention, in BGM mode, effect processing including at least one of dynamic range compression, high and low frequency cut, distortion addition, pop noise addition, and playback pitch change is performed on the audio data to be played back based on the analysis results of the music information or melody of the audio data to be played back.

[0010] This makes it possible to play and output digitally remastered old music with sound quality that is as if it were played on the audio equipment (record player, cassette tape recorder, etc.) of the time. This prevents situations where a user becomes engrossed in listening to high-quality digitally remastered old music and it disrupts work or sleep. Furthermore, dynamic range compression makes it possible to play and output high-quality music with a wide dynamic range, such as classical music, without interruption, even when the volume is reduced to a level suitable for background music. This eliminates the need for interruptions in the sound that can annoy users and disrupt their work or sleep.

[0011] As described above, according to the present invention, it is possible to play back high-quality audio data with a quality suitable for background music. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a schematic diagram of a wireless audio system according to an embodiment of the present invention. [Figure 2] FIG. 2 is a diagram showing a schematic functional configuration of the wireless audio player 1. As shown in FIG. [Figure 3] FIG. 3 is a flow diagram illustrating the operation mode setting process of the wireless audio player 1. [Figure 4] FIG. 4 is a flow diagram illustrating the audio playback process of the wireless audio player 1. [Figure 5] FIG. 5 is a flowchart for explaining the BGM mode playback process (S22) shown in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0013] An embodiment of the present invention will be described below with reference to the drawings.

[0014] FIG. 1 is a schematic diagram of a wireless audio system according to the present embodiment.

[0015] As shown in the figure, the wireless audio system according to this embodiment is configured to include a wireless audio player 1, a remote controller 2, and a media server 3.

[0016] The media server 3 is connected to the wireless audio player 1 via a network 4 such as a WAN (Wide Area Network) or LAN and an access point 5, and distributes audio data of songs including high-quality audio data such as high-resolution audio to the wireless audio player 1.

[0017] The remote controller 2 is used by the user to remotely operate the wireless audio player 1, and can be a dedicated product or can be realized by executing a specified program (application software) on a mobile device such as a smartphone or tablet PC.

[0018] The wireless audio player 1 is an audio device that supports high-quality audio data of music such as high-resolution audio, and plays and outputs the audio data of music downloaded from the media server 3. The wireless audio player 1 also has a normal mode and a background music mode as its operating modes, and when the operating mode is set to background music mode, the audio data of music downloaded from the media server 3 is processed to a sound quality suitable for background music before being played and output.

[0019] FIG. 2 is a diagram showing a schematic functional configuration of the wireless audio player 1. As shown in FIG.

[0020] As shown in the figure, the wireless audio player 1 includes a wireless LAN interface unit 10, an instruction receiving unit 11, an audio playback unit 12, a speaker unit 13, a music information acquisition unit 14, a sound quality analysis unit 15, an effect processing unit 16, a mode switching unit 17, and a main control unit 18.

[0021] The wireless LAN interface unit 10 is an interface for communicating with the media server 3 via the access point 5 and the network 4, or for communicating with the remote controller 2 via the access point 5, by wireless LAN.

[0022] The instruction receiving unit 11 receives various instructions such as a playback instruction, an operation mode setting instruction, etc. from the remote controller 2 via the wireless LAN interface unit 10.

[0023] The audio playback unit 12 plays back the input audio data to be played back, and outputs the audio signal, which is the playback signal, to the mode switching unit 17 .

[0024] The speaker unit 13 outputs the audio signal output from the mode switching unit 17 or the effect processing unit 16 as sound.

[0025] The music information acquisition unit 14 acquires music information added to the audio data to be played back, and notifies the effect processing unit 16 of the release year of the music included in the music information.

[0026] The sound quality analysis unit 15 analyzes the sound quality of the audio data to be played back, and notifies the effect processing unit 16 of the analysis results. Specifically, the sound quality analysis unit 15 analyzes the dynamic range, frequency band, and noise components of the audio data, and notifies the effect processing unit 16 of the analysis results.

[0027] The effect processor 16 applies effect processing to the input audio signal (playback signal) based on the release year of the song notified by the song information acquirer 14 and the sound quality analysis result notified by the sound quality analyzer 15. The effect-processed audio signal is then output to the speaker 13.

[0028] Specifically, the effect processor 16 selects at least one of the following effect processes to apply to the audio signal based on the era to which the song was released, as notified by the song information acquirer 14. Table 1 shows an example of the correspondence between the era of songs and the effect processes to be applied.

[0029] [Table 1]

[0030] Here, "dynamic range compression" compresses the dynamic range of the audio signal. "Dynamic range compression" converts the audio signal into a more uniform sound with smaller sound pressure differences, preventing sound dropouts when output at low volume.

[0031] "High and low frequency cut" cuts out high frequency components (above 7.5 kHz) and low frequency components (below 20 Hz) from the audio signal, outside the frequency band that can be transmitted by AM radio broadcasts, for example. By applying "high and low frequency cut," it is possible to output an audio signal with sound quality similar to that of listening to an AM radio broadcast.

[0032] "Add distortion" adds distortion (crackling) to the audio signal by clipping. By applying "Add distortion", you can output an audio signal with a sound quality that sounds as if it was coming from a speaker that has deteriorated over time.

[0033] "Add Crackle Noise" adds crackle noise (click noise) to the audio signal. By applying "Add Crackle Noise", you can output an audio signal with a sound quality that sounds as if you were playing a scratched analog record on a record player.

[0034] "Playback pitch change" changes the playback pitch (sound height) of the audio signal. By applying "Playback pitch change", it is possible to output an audio signal with a sound quality that is as if it were being played on a record player or cassette tape recorder with a lot of wow and flutter.

[0035] As shown in Table 1, at least one of the following effects is selected based on the release date of the audio data being played: dynamic range compression, high- and low-frequency cut, distortion addition, crackle noise addition, and playback pitch change. The selected effect is then applied to the playback signal of this audio data. This makes it possible to output digitally remastered old music (e.g., music from before the 1990s) with sound quality that is similar to that of the audio equipment (record player, cassette tape recorder, etc.) from that time. For more recent music (e.g., music from after 2000), dynamic range compression converts the sound to a more uniform sound with smaller sound pressure differences, allowing it to be output without interruption even when the volume is reduced to a level suitable for background music.

[0036] Furthermore, the effect processor 16 determines whether or not to perform the effect processing selected based on the release year of the audio data to be played back, based on the analysis result of the sound quality notified by the sound quality analyzer 15.

[0037] Specifically, if the dynamic range of the audio data being played is narrower than a predetermined width—in other words, if the sound can be output without interruption even when the volume is reduced to a level suitable for background music—the application of the "dynamic range compression" effect is omitted. Furthermore, if the audio data being played does not contain certain high- and low-frequency components (for example, if it does not contain high- and low-frequency components that cannot be transmitted via AM radio broadcasting), the application of the "high- and low-frequency cut" effect is omitted. Furthermore, if the audio data being played contains noise components at a predetermined frequency, the application of the "distortion addition" and "crackle noise addition" effects is omitted. This prevents further degradation of the audio signal being played back when the audio data being played originally has sound quality suitable for background music (for example, audio data of old music that has not been digitally remastered).

[0038] The mode switching unit 17 switches the output destination of the audio signal input from the audio playback unit 12 depending on the operation mode. Specifically, when the operation mode is set to the normal mode, the mode switching unit 17 outputs the audio signal input from the audio playback unit 12 to the speaker unit 13. When the operation mode is set to the BGM mode, the mode switching unit 17 outputs the audio signal input from the audio playback unit 12 to the effect processing unit 16.

[0039] The main control unit 18 comprehensively controls the units 10 to 17 of the wireless audio player 1 itself, and performs processing in accordance with the various instructions received by the instruction receiving unit 11.

[0040] 2 may be realized in hardware using an integrated logic IC such as an ASIC (Application Specific Integrated Circuit) or FPGA (Field Programmable Gate Array), or in software using a computer such as a DSP (Digital Signal Processor).Alternatively, it may be realized by a general-purpose computer such as a PC that includes a CPU, memory, an auxiliary storage device such as a flash memory or a hard disk drive, a communication device such as a wireless LAN adapter, and a speaker, in which the CPU loads a predetermined program from the auxiliary storage device into the memory and executes it.

[0041] FIG. 3 is a flow diagram illustrating the operation mode setting process of the wireless audio player 1.

[0042] When the instruction receiving unit 11 receives an operation mode setting instruction accompanied by the designation of an operation mode from the remote controller 2 via the wireless LAN interface unit 10 (YES in S10), it notifies the main control unit 18 of this operation mode setting instruction. instructions The contents are analyzed (S11), and if normal mode is specified ("normal mode" in S11), the operation mode of the wireless audio player 1 itself is set to normal mode, and the output destination of the mode switching unit 17 is switched to the speaker unit 13 (S12). On the other hand, if BGM mode is specified ("BGM mode" in S11), the operation mode of the wireless audio player 1 itself is set to BGM mode, and the output destination of the mode switching unit 17 is switched to the effect processing unit 16 (S13).

[0043] FIG. 4 is a flow diagram illustrating the audio playback process of the wireless audio player 1.

[0044] This flow starts when the instruction receiving unit 11 receives a playback instruction accompanied by the specification of a playback target from the remote controller 2 via the wireless LAN interface unit 10.

[0045] First, the instruction receiving unit 11 passes the playback instruction received from the remote controller 2 to the main control unit 18. In response to this, the main control unit 18 accesses the media server 3 via the wireless LAN interface unit 10 and downloads the audio data to be played back specified in the playback instruction from the media server 3 together with the music information thereof (S20). If the operation mode of the wireless audio player 1 itself is set to the normal mode ("normal mode" in S21), the audio data to be played back downloaded from the media server 3 is played back in the normal mode (S21). That is, the audio data to be played back downloaded from the media server 3 is played back by the audio playback unit 12, and an audio signal representing the playback signal is output from the speaker unit 13 via the mode switching unit 17. On the other hand, if the operation mode of the wireless audio player 1 itself is set to the BGM mode ("BGM mode" in S21), the audio data to be played back downloaded from the media server 3 is played back in the BGM mode (S22).

[0046] FIG. 5 is a flowchart for explaining the BGM mode playback process (S22) shown in FIG.

[0047] First, the music information acquisition unit 14 acquires music information attached to the audio data to be played back that has been downloaded from the media server 3 via the audio playback unit 12, and notifies the effects processing unit 16 of the release year of the music included in the music information (S220). In response to this, the effects processing unit 16 selects at least one of the effect processes to be applied to the audio signal from among dynamic range compression, high-frequency and low-frequency frequency cut, distortion addition, pop noise addition, and playback pitch change, in the manner described above, based on the decade to which the release year of the music notified by the music information acquisition unit 14 belongs (S221).

[0048] Next, the sound quality analysis unit 15 analyzes the sound quality of the audio data to be reproduced and notifies the effect processing unit 16 of the analysis result (S222). In response to this, the effect processing unit 16 determines whether or not to implement the effect processing selected in S221 (S223) based on the sound quality analysis result notified by the sound quality analysis unit 15. This determines whether or not to implement the effect processing to be applied to the audio signal, which is the playback signal of the audio data to be reproduced.

[0049] Then, the audio playback unit 12 adjusts the playback volume to a predetermined volume that is preset as the volume of the background music (S224), and starts playing the audio data to be played (S225). The audio signal, which is the playback signal of the audio data to be played, is input to the effect processing unit 16 via the mode switching unit 17, and if the effect processing to be performed is required, the effect processing to be performed is applied, and then the audio signal is output from the speaker unit 13.

[0050] One embodiment of the present invention has been described above.

[0051] In this embodiment, in BGM mode, effect processing including at least one of dynamic range compression, high-frequency and low-frequency cut, distortion addition, pop noise addition, and playback pitch change is performed on the audio data to be played back based on the music information of the audio data. This makes it possible to play and output, for example, digitally remastered old music with sound quality that sounds as if it were played back on an audio device (such as a record player or cassette tape recorder) from that time. This prevents situations where listening to high-quality digitally remastered old music distracts you from concentrating on your work or prevents you from falling asleep. In this way, this embodiment makes it possible to play high-quality audio data with sound quality suitable for BGM.

[0052] Furthermore, in this embodiment, whether or not to apply effect processing selected based on the music information of the audio data to be played is determined based on the analysis results of the sound quality of this audio data. This makes it possible to prevent further degradation of the audio signal being played back when the audio data to be played back originally has sound quality suitable for background music (for example, audio data of old music that has not been digitally remastered).

[0053] The present invention is not limited to the above-described embodiment, and various modifications are possible within the scope of the present invention.

[0054] For example, in the above embodiment, the wireless audio player 1 selects the effect processing to be applied to the audio signal, which is the playback signal of the audio data, based on the release year of the music included in the music information of the audio data to be played. However, the present invention is not limited to this. The effect processing to be applied to the audio signal, which is the playback signal of the audio data, may be selected based on the genre of the music included in the music information of the audio data to be played. For example, in the case of the genre "classical," classical music generally has a wide dynamic range, so the effect processing " Dynamic Range By applying "compression" and "playback pitch change" to enable uninterrupted sound playback even at low volumes, and by outputting an audio signal with a sound quality that is as if it were being played on a record player or cassette tape recorder with a lot of wow and flutter, it is possible to play back with a sound quality suitable for background music.In the case of the "rock" genre, since rock generally has a wide frequency range, the effect processing "high and low frequency cut" and "distortion addition" are applied to output an audio signal with a sound quality that is as if you were listening to an AM radio broadcast through speakers that have deteriorated over time, so it is possible to play back with a sound quality suitable for background music.

[0055] Furthermore, in the above embodiment, the wireless audio player 1 selects effect processing to be applied to the audio signal, which is the playback signal of the audio data, based on the music information of the audio data to be played. However, the present invention is not limited to this. The wireless audio player 1 may be provided with a music style analysis unit that analyzes the music style of the audio data to be played, and the effect processing unit 16 may select effect processing to be applied to the audio signal based on the music genre identified by the music style analyzed by the music style analysis unit. In this way, even if music information of the audio data to be played cannot be obtained from the media server 3, appropriate effect processing can be applied to the audio signal, which is the playback signal of this audio data.

[0056] In the above embodiment, the wireless audio player 1 selects effect processing to be applied to the audio data to be played from among dynamic range compression, high and low frequency cut, distortion addition, pop noise addition, and playback pitch change. However, the present invention is not limited to this. Any effect processing may be used as long as it can convert high-quality audio data into an audio signal with sound quality suitable for background music. For example, there are effect processings that combine two or more of dynamic range compression, high and low frequency cut, distortion addition, pop noise addition, and playback pitch change to achieve sound quality as if played on a record player using an MM (Moving Magnet) cartridge, and effect processing that achieves sound quality as if played on a record player using an MM (Moving Magnet) cartridge. MC It is also possible to prepare effect processing that can achieve sound quality similar to that of a record player using a (moving coil) cartridge, and select from these effect processing to apply to the audio data based on the analysis results of the music information or melody of the audio data to be played.

[0057] In the above embodiment, whether or not to apply effect processing selected based on the music information of the audio data to be played is determined based on the analysis results of the sound quality of the audio data. However, the present invention is not limited to this. For example, if the audio data distributed by the media server 3 is limited to high-quality audio data such as high-resolution audio, the process of determining whether or not to apply effect processing based on the analysis results of the sound quality of the audio data may be omitted.

[0058] Furthermore, in the above embodiment, the wireless audio player 1 accepts an operation mode setting instruction from the remote controller 2, but the present invention is not limited to this. The wireless audio player 1 may be provided with an operation mode switching button, and an operation mode setting instruction may be accepted from the user via the switching button. Alternatively, the wireless audio player 1 may be equipped with a timer, and the operation mode may be set to BGM mode when the current time reaches a preset BGM mode transition time, and the operation mode may be set to normal mode when the current time reaches a preset normal mode transition time. Alternatively, the remote controller 2 may be equipped with a scheduler, which monitors the user's schedule, and transmits an operation mode setting instruction specifying BGM mode to the wireless audio player 1 when the current time transitions to a work or sleep schedule, and transmits an operation mode setting instruction specifying normal mode to the wireless audio player 1 when the current time deviates from the work or sleep schedule.

[0059] In the above embodiment, the present invention has been described as being applied to a wireless audio player, but the present invention is not limited to this. The present invention can be widely applied to audio devices capable of playing high-quality audio data, such as high-resolution audio. [Explanation of symbols]

[0060] 1: Wireless audio player, 2: Remote controller, 3: Media server, 4: Network, 5: Access point, 10: Wireless LAN interface unit, 11: Instruction reception unit, 12: Audio playback unit, 13: Speaker unit, 14: Music information acquisition unit, 15: Sound quality analysis unit, 16: Effect processing unit, 17: Mode switching unit, 18: Main control unit

Claims

1. An audio device that reproduces and outputs audio data, mode setting means for setting the operation mode to a normal mode or a BGM (Background Music) mode; an effect processing means for selecting and implementing effect processing, when the BGM mode is set by the mode setting means, based on music information or analysis results of the audio data to be reproduced, the effect processing including at least one of dynamic range compression, high and low frequency cut, distortion addition, pop noise addition, and reproduction pitch change to be applied to the audio data to be reproduced; a sound quality analysis means for analyzing the sound quality of the audio data to be reproduced, The effect processing means The necessity of effect processing to be applied to the audio data to be reproduced, which is selected based on the song information or analysis result of the audio data to be reproduced, is changed based on the sound quality analyzed by the sound quality analysis means.

1. An audio device comprising:

2. 2. An audio device according to claim 1, The audio data playback device further includes a music information acquisition unit that acquires music information of the audio data to be played back that has been downloaded from a media server that distributes the audio data to be played back, The effect processing means Selecting an effect process to be applied to the audio data to be played back based on the year of release or genre of the music included in the music information acquired by the music information acquisition means 1. An audio device comprising:

3. 2. An audio device according to claim 1, The apparatus further comprises a music tune analysis means for analyzing the music tune of the audio data to be reproduced, The effect processing means Selecting an effect process to be applied to the audio data to be played back based on the genre of the music identified by the melody analyzed by the melody analysis means.

1. An audio device comprising:

4. 4. An audio device according to claim 1, The mode setting means The operation mode is set in accordance with an instruction received via an operation button provided on the audio device itself or a controller for remotely operating the audio device itself.

1. An audio device comprising:

5. A program that causes a computer to function as an audio device that plays and outputs audio data, a mode setting means for setting the operation mode to a normal mode or a BGM (Background Music) mode; an effect processing means for selecting and implementing effect processing including at least one of dynamic range compression, high and low frequency cut, distortion addition, pop noise addition, and playback pitch change to be applied to the audio data to be played back, based on music information or analysis results of the audio data to be played back, when the BGM mode is set by the mode setting means; causing the computer to function as sound quality analysis means for analyzing the sound quality of the audio data to be reproduced; The effect processing means The necessity of effect processing to be applied to the audio data to be reproduced, which is selected based on the song information or analysis result of the audio data to be reproduced, is changed based on the sound quality analyzed by the sound quality analysis means. A program characterized by:

6. 1. A method for reproducing audio data by an audio device, comprising: The audio device is The operation modes include a normal mode and a BGM (Background Music) mode. When the operation mode is set to the BGM mode, Based on the music information or analysis results of the audio data to be reproduced, an effect process including at least one of dynamic range compression, high-frequency and low-frequency cut, distortion addition, crackle noise addition, and reproduction pitch change to be applied to the audio data to be reproduced is selected, the sound quality of the audio data to be reproduced is analyzed, and based on the analyzed sound quality, the necessity of implementing the selected effect process is changed, and the audio data to be reproduced to which the necessity of implementing the effect process has been changed is reproduced and output.

10. An audio playback method comprising:

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