A headphone volume control method calculates a level of a sound signal, which is captured by a microphone, during a first period, determines a target value of a sound volume based on the above-mentioned level, and gradually changes a reproduction volume of content to be reproduced to the above-mentioned target value over a second period.

A signal processing method, especially for audio signals, comprises: receiving input signal samples having source signal portions associated with respective time periods (In_n−1); generating parameters associated with the respective time periods by processing the respective input signal samples, in which the step of generating the parameters has an associated non-zero latency period so that generating step provides a parameter p in a time period (T_n−1) later than the start of the respective time period; and generating an output data portion associated with a given time period (Out_n−1 using a signal processing function F which depends upon the input signal samples in the given time period (In_n−1) and an approximated parameter p′ (1110) associated with a time period other than the given time period (T_n−2).

A signal processing method, especially for audio signals, comprises: receiving input signal samples having source signal portions associated with respective time periods (In_n−1); generating parameters associated with the respective time periods by processing the respective input signal samples, in which the step of generating the parameters has an associated non-zero latency period so that generating step provides a parameter p in a time period (T_n−1) later than the start of the respective time period; and generating an output data portion associated with a given time period (Out_n−1 using a signal processing function F which depends upon the input signal samples in the given time period (In_n−1) and an approximated parameter p′ (1110) associated with a time period other than the given time period (T_n−2).

A headphone volume control method calculates a level of a sound signal, which is captured by a microphone, during a first period, determines a target value of a sound volume based on the above-mentioned level, and gradually changes a reproduction volume of content to be reproduced to the above-mentioned target value over a second period.

A system for creating motion adaptive audio experiences using available acceleration and speed data of a host device, such as a vehicle or a mobile phone in a vehicle, to determine acceleration and speed values, as well as to identify moments when the device has stopped moving making the speed zero. The system selects playback characteristics of digital audio files based on acceleration and speed of the device and orchestrates playback of the selected digital audio files through an existing audio system. As such, when the speed or acceleration of the vehicle changes, the audio play back to the user is also changed in order to provide an audio experience for users that is adaptive to vehicle motion.

A headphone volume control method calculates a level of a sound signal, which is captured by a microphone, during a first period, determines a target value of a sound volume based on the above-mentioned level, and gradually changes a reproduction volume of content to be reproduced to the above-mentioned target value over a second period.

A system is provided to analyze distortion in an electronic or electromechanical device, which may include testing with one or more modulated signals and/or with one or more demodulators. In one embodiment a change in pitch (or frequency) is measured at an output of the device. One or more signals from a demodulator output may be measured for an amplitude, noise, phase, aliasing, spurious signal, and/or frequency modulation effect. In another embodiment a musical signal may be used as a test signal. Providing additional test signals to the device can induce a cross-modulation distortion signal (or time varying cross-modulation distortion signal) from an output of the device. Also utilizing at least one additional filter, filter bank, demodulator and or frequency converter and or frequency multiplier provides extra examination of distortion. Also frequency and/or phase response can be measured with the presence of a de-sensing signal and or another signal that induce near slew rate limiting or near overload condition of the device under test. Another system is provided to analyze modulation index differences between input and output signals for a test signal including modulation. Another system includes providing a nested or layered modulated signal and/or a nested or layered demodulation apparatus or method. Yet another system provides for evaluating for spurious sideband signals via an un-modulated test signal.

A system is provided to analyze distortion in an electronic or electromechanical device, which may include testing with one or more modulated signals and/or with one or more demodulators. In one embodiment a change in pitch (or frequency) is measured at an output of the device. One or more signals from a demodulator output may be measured for an amplitude, noise, phase, aliasing, spurious signal, and/or frequency modulation effect. In another embodiment a musical signal may be used as a test signal. Providing additional test signals to the device can induce a cross-modulation distortion signal (or time varying cross-modulation distortion signal) from an output of the device. Also utilizing at least one additional filter, filter bank, demodulator and or frequency converter and or frequency multiplier provides extra examination of distortion. Also frequency and/or phase response can be measured with the presence of a de-sensing signal and or another signal that induce near slew rate limiting or near overload condition of the device under test. Another system is provided to analyze modulation index differences between input and output signals for a test signal including modulation. Another system includes providing a nested or layered modulated signal and/or a nested or layered demodulation apparatus or method. Yet another system provides for evaluating for spurious sideband signals via an un-modulated test signal.

A system is provided to analyze frequency (or phase) modulation distortion in an audio device, which may include testing with audio frequencies. In one embodiment a change in pitch (or frequency) is measured at an output of the audio device. One or more distortion signals from the audio device may be measured for an amplitude, phase, and or frequency modulation effect. In another embodiment a musical signal may be used as a test signal. Providing additional test signals to the audio device can induce a time varying cross-modulation distortion signal (or static cross-modulation distortion signal) from an output of the audio device. Also utilizing at least one additional filter, filter bank, demodulator and or frequency converter and or frequency multiplier provides extra examination of distortion. Also frequency and or phase response can be measured with the presence of a de-sensing signal and or another signal that induce near slew rate limiting or near overload condition of the device under test. Another system is provided to analyze modulation index differences between input and output signals for a test signal including modulation.

A system is provided to analyze frequency (or phase) modulation distortion in an audio device, which may include testing with audio frequencies. In one embodiment a change in pitch (or frequency) is measured at an output of the audio device. One or more distortion signals from the audio device may be measured for an amplitude, phase, and or frequency modulation effect. In another embodiment a musical signal may be used as a test signal. Providing additional test signals to the audio device can induce a time varying cross-modulation distortion signal (or static cross-modulation distortion signal) from an output of the audio device. Also utilizing at least one additional filter, filter bank, demodulator and or frequency converter and or frequency multiplier provides extra examination of distortion. Also frequency and or phase response can be measured with the presence of a de-sensing signal and or another signal that induce near slew rate limiting or near overload condition of the device under test. Another system is provided to analyze modulation index differences between input and output signals for a test signal including modulation.