# US 2014/0153743 A1 · Audio processing device and method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0153743 A1 - Document ID: US20140153743A1 - Status: Published application - Kind: A1 - Application number: 14/080,373 - Filed: 2013-11-14 - Published: 2014-06-05 - Earliest claimed: 2012-12-03 - Assignees: Fujitsu Limited - Applicants: Fujitsu Limited - Inventors: Takeshi OTANI; Taro TOGAWA; Chisato ISHIKAWA; Masanao SUZUKI - Web page: https://patentgrep.com/patent/US20140153743A1 ## CPC - H04R 3/04: for correcting frequency response - G10L 21/0208: Noise filtering - H03G 5/18: in untuned amplifiers - H04R 3/007: {Protection circuits for transducers} - H04R 29/001: {for loudspeakers (H04R29/007 takes precedence)} - H04R 2430/01: Aspects of volume control, not necessarily automatic, in sound systems - H04R 2430/03: Synergistic effects of band splitting and sub-band processing - H04R 2499/11: Transducers incorporated or for use in hand-held devices, e.g. mobile phones, PDA's, camera's - H04R: LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; ELECTRIC HEARING AIDS; PUBLIC ADDRESS SYSTEMS (producing sounds with frequency not determined by supply frequency G10K) - G10L: SPEECH ANALYSIS TECHNIQUES OR SPEECH SYNTHESIS; SPEECH RECOGNITION; SPEECH OR VOICE PROCESSING TECHNIQUES; SPEECH OR AUDIO CODING OR DECODING - H03G: CONTROL OF AMPLIFICATION ## Abstract An audio processing device includes a setting section that sets a reproduction sampling frequency Fplay and a recording sampling frequency Frec higher than Fplay, a digital-to-analogue converter that based on Fplay converts a sound source signal that is a digital signal into a reproduction signal that is an analogue signal, an analogue-to-digital converter that based on Frec converts a recording signal that is an analogue signal converter into an input signal that is a digital signal, a signal separator that separates the input signal into a low region signal contained in a band of less than Fplay and a high region signal contained in a band of the Fplay and higher, and a breakup detector that detects whether or not breakup is occurring in the reproduced sound based on power of the high region signal. ## Claims ### Claim 1 An audio processing device comprising: a setting section that sets a reproduction sampling frequency and a recording sampling frequency higher than the reproduction sampling frequency; a digital-to-analogue converter that, based on the reproduction sampling frequency, converts a sound source signal that is a digital signal into a reproduction signal that is an analogue signal; an analogue-to-digital converter that, based on the recording sampling frequency, converts a recording signal that is an analogue signal obtained by recording sound that has been reproduced according to the reproduction signal converted by the digital-to-analogue converter into an input signal that is a digital signal; a signal separator that separates the input signal converted by the analogue-to-digital converter into a low region signal contained in a band of less than the reproduction sampling frequency and a high region signal contained in a band of the reproduction sampling frequency and higher; and a breakup detector that detects whether or not breakup is occurring in the reproduced sound based on power of the high region signal, or based on a difference or ratio between power of the high region signal and power of the low region signal. ### Claim 2 (depends on 1) The audio processing device of claim 1, wherein the setting section sets the recording sampling frequency at twice the reproduction sampling frequency. ### Claim 3 (depends on 1) The audio processing device of claim 1, wherein the breakup detector detects breakup as occurring in the reproduced sound when the power of the high region signal is greater than a predetermined first threshold value, or when a difference or a ratio between the power of the high region signal and the power of the low region signal is smaller than a predetermined second threshold value. ### Claim 4 (depends on 1) The audio processing device of claim 1, further comprising: a synchronization section that stores a specific time period worth of a sound source signal prior to converting to the reproduction signal, and then, based on a correlation between the stored sound source signal and the input signal, synchronizes the stored sound source signal and the input signal; a storage controller that stores power of the stored sound source signal for synchronizing to an input signal when breakup is detected by the breakup detector; and a reproduction controller that, when power of a sound source signal prior to converting to the reproduction signal is greater than the power of the stored sound source signal, controls the sound source signal prior to converting to the reproduction signal such that breakup does not occur. ### Claim 5 (depends on 4) The audio processing device of claim 4, wherein the reproduction controller attenuates the sound source signal prior to converting to the reproduction signal such that the power of the sound source signal prior to converting to the reproduction signal is the power of the stored sound source signal or lower. ### Claim 6 (depends on 1) The audio processing device of claim 1, further comprising a suppressor that suppresses the low region signal when breakup is detected by the breakup detector. ### Claim 7 (depends on 6) The audio processing device of claim 6, further comprising: a breakup estimator that estimates a breakup signal that is a low region signal containing a breakup component corresponding to the high region signal in which breakup has been detected by the breakup detector, wherein the suppressor suppresses the low region signal by multiplying the low region signal by a gain that is larger the smaller the difference is between the breakup signal estimated by the breakup estimator and the low region signal separated by the signal separator. ### Claim 8 An audio processing method comprising: setting a reproduction sampling frequency and a recording sampling frequency higher than the reproduction sampling frequency; based on the reproduction sampling frequency, converting a sound source signal that is a digital signal into a reproduction signal that is an analogue signal; based on the recording sampling frequency, converting a recording signal that is an analogue signal obtained by recording sound that has been reproduced according to the converted reproduction signal into an input signal that is a digital signal; separating the converted input signal into a low region signal contained in a band of less than the reproduction sampling frequency and a high region signal contained in a band of the reproduction sampling frequency and higher; and detecting whether or not breakup is occurring in the reproduced sound based on power of the high region signal, or based on a difference or ratio between power of the high region signal and power of the low region signal. ### Claim 9 (depends on 8) The audio processing method of claim 8, wherein the recording sampling frequency is set at twice the reproduction sampling frequency. ### Claim 10 (depends on 8) The audio processing method of claim 8, wherein breakup is detected as occurring in the reproduced sound when the power of the high region signal is greater than a predetermined first threshold value, or when a difference or a ratio between the power of the high region signal and the power of the low region signal is smaller than a predetermined second threshold value. ### Claim 11 (depends on 8) The audio processing method of claim 8, further comprising: storing a specific time period worth of a sound source signal prior to converting to the reproduction signal, and then synchronizing the stored sound source signal and the input signal based on a correlation between the stored sound source signal and the input signal; storing power of the stored sound source signal for synchronizing to an input signal when breakup is detected; and when power of a sound source signal prior to converting to the reproduction signal is greater than the power of the stored sound source signal, controlling the sound source signal prior to converting to the reproduction signal such that breakup does not occur. ### Claim 12 (depends on 11) The audio processing method of claim 11, wherein the sound source signal prior to converting to the reproduction signal is attenuated such that the power of the sound source signal prior to converting to the reproduction signal is the power of the stored sound source signal or lower. ### Claim 13 (depends on 8) The audio processing method of claim 8, further comprising suppressing the low region signal when breakup is detected. ### Claim 14 (depends on 13) The audio processing method of claim 13, further comprising: estimating a breakup signal that is a low region signal containing a breakup component corresponding to the high region signal in which breakup has been detected, wherein the low region signal is suppressed by multiplying the low region signal by a gain that is larger the smaller the difference is between the estimated breakup signal and the separated low region signal. ### Claim 15 A recording medium having recorded thereon an audio processing program for causing a computer to execute a process, the process comprising: setting a reproduction sampling frequency and a recording sampling frequency higher than the reproduction sampling frequency; based on the reproduction sampling frequency, converting a sound source signal that is a digital signal into a reproduction signal that is an analogue signal; based on the recording sampling frequency, converting a recording signal that is an analogue signal obtained by recording sound that has been reproduced according to the converted reproduction signal into an input signal that is a digital signal; separating the converted input signal into a low region signal contained in a band of less than the reproduction sampling frequency and a high region signal contained in a band of the reproduction sampling frequency and higher; and detecting whether or not breakup is occurring in the reproduced sound based on power of the high region signal, or based on a difference or ratio between power of the high region signal and power of the low region signal. ### Claim 16 (depends on 15) The recording medium having recorded thereon an audio processing program of claim 15, wherein the recording sampling frequency is set at twice the reproduction sampling frequency. ### Claim 17 (depends on 15) The recording medium having recorded thereon an audio processing program of claim 15, wherein breakup is detected as occurring in the reproduced sound when the power of the high region signal is greater than a predetermined first threshold value, or when a difference or a ratio between the power of the high region signal and the power of the low region signal is smaller than a predetermined second threshold value. ### Claim 18 (depends on 15) The recording medium having recorded thereon an audio processing program of claim 15, wherein the process further comprises: storing a specific time period worth of a sound source signal prior to converting to the reproduction signal, and then synchronizing the stored sound source signal and the input signal based on a correlation between the stored sound source signal and the input signal; storing power of the stored sound source signal for synchronizing to an input signal when breakup is detected; and when power of a sound source signal prior to converting to the reproduction signal is greater than the power of the stored sound source signal, controlling the sound source signal prior to converting to the reproduction signal such that breakup does not occur. ### Claim 19 (depends on 18) The recording medium having recorded thereon an audio processing program of claim 18, wherein the sound source signal prior to converting to the reproduction signal is attenuated such that the power of the sound source signal prior to converting to the reproduction signal is the power of the stored sound source signal or lower. ### Claim 20 (depends on 15) The recording medium having recorded thereon an audio processing program of claim 15, wherein the process further comprises suppressing the low region signal when breakup is detected. ### Claim 21 (depends on 20) The recording medium having recorded thereon an audio processing program of claim 20, wherein the process further comprises: estimating a breakup signal that is a low region signal containing a breakup component corresponding to the high region signal in which breakup has been detected, wherein the low region signal is suppressed by multiplying the low region signal by a gain that is larger the smaller the difference is between the estimated breakup signal and the separated low region signal.