Abstract: An audio signal processing apparatus includes: a first filtering unit which outputs an audio signal while attenuating frequency components except for preset frequency components; a detecting unit which detects a sound volume level; an amplitude limiting unit which calculates an amplitude limiting level corresponding to the sound volume level, and which limits a part of a waveform of the audio signal output from the first filtering unit; a second filtering unit which outputs the audio signal output from the amplitude limiting unit while attenuating frequency components except for preset frequency components including a part of the frequency band of the audio signal output from the first filtering unit, and a part of the frequency band of the harmonics; a compressing unit which compresses a dynamic range of the audio signal; and an adding unit which adds the audio signal output from the compressing unit to the input audio signal.

Abstract: An effect adding method, includes: applying different gains to a positive side waveform portion and a negative side waveform portion of an audio signal respectively when absolute values of input levels of the positive side waveform portion and the negative side waveform portion are smaller than a predetermined value; producing a higher range component of the audio signal based on a high range component of the audio signal to which the gain is applied, the higher range component being higher in frequency than the high range component; producing a lower range component of the audio signal based on a low range component of the audio signal to which the gain is applied, the lower range component being lower in the frequency than the low range component; and synthesizing an audio signal having an effect sound by adding the audio signal to which the different gains are applied, the higher range component, and the lower range component with each other.

Abstract: A sound volume controller includes a level adjustment section that adjusts a level of an input audio signal and outputs the adjusted input audio signal as an output audio signal, a level detection section that detects the level of the input audio signal, a volume value detection section that detects a volume value set by a user, a coefficient table storage section that stores a coefficient table which describes a relation between levels of the output audio signal and levels of the input audio signal, a coefficient table change section that changes the coefficient table stored in the coefficient table storage section in accordance with the volume value detected by the volume value detection section, and a setting section that sets an amount of level adjustment of the level adjustment section in accordance with the level of the input audio signal detected by the level detection section and the coefficient table.

Abstract: An audio signal processing device is designed to enhance the low-pitch register of an audio signal by generating harmonics causing a missing fundamental effect with a light load of processing but without damaging an audio waveform. The audio signal processing device includes a filtering part (e.g. a band-pass filter configured of a high-pass filter and a low-pass filter) that extracts a low-pitch signal from an audio signal input thereto; a dynamic range compression part that compresses a dynamic range of the low-pitch signal by use of a time-variant gain relative to a peak of the low-pitch signal, which is detected via a peak hold operation using a predetermined time constant, thus producing a compressed signal; and an adder that adds the compressed signal to the audio signal so as to produce a processed audio signal including harmonics.

Abstract: A content reproduction apparatus that adopts a content processing method includes a video processor, a video analyzer, and an audio processor for processing audio data and video data input thereto. The video analyzer analyzes video characteristics of video data such as resolutions, compressive distortions, and real frame rates. The video processor processes video data in accordance with video processing, which is determined based on analyzed video characteristics of video data. The audio processor processes audio data in accordance with audio processing, such as dynamic range compression and/or frequency component extension/enhancement, which is determined based on analyzed video characteristics of video data. Thus, it is possible to reproduce sound in an articulate manner depending on the video quality, which is either professional-level video shooting or nonprofessional-level video shooting.

Abstract: LPF and HPF extract bass and treble ranges, respectively, from an input sound signal, and bass and treble boost circuits perform dynamic range expansion/contraction on the extracted bass- and treble-range sound signals in accordance with input levels of the sound signals. The input sound signal and the sound signals output from the boost circuits are added together. There may also be provided coefficient calculation sections for calculating filter coefficients on the basis of the levels of the sound signals extracted by the LPF and HPF. In this case, the bass and treble boost sections perform, in accordance with the filter coefficients calculated by the corresponding coefficient calculation sections, filter processes for increasing/decreasing the levels of the bass and treble ranges, respectively.

Abstract: An effect adding method, includes: applying different gains to a positive side waveform portion and a negative side waveform portion of an audio signal respectively when absolute values of input levels of the positive side waveform portion and the negative side waveform portion are smaller than a predetermined value; producing a higher range component of the audio signal based on a high range component of the audio signal to which the gain is applied, the higher range component being higher in frequency than the high range component; producing a lower range component of the audio signal based on a low range component of the audio signal to which the gain is applied, the lower range component being lower in the frequency than the low range component; and synthesizing an audio signal having an effect sound by adding the audio signal to which the different gains are applied, the higher range component, and the lower range component with each other.

Abstract: An effect adding method, includes: applying different gains to a positive side waveform portion and a negative side waveform portion of an audio signal respectively when absolute values of input levels of the positive side waveform portion and the negative side waveform portion are smaller than a predetermined value; producing a higher range component of the audio signal based on a high range component of the audio signal to which the gain is applied, the higher range component being higher in frequency than the high range component; producing a lower range component of the audio signal based on a low range component of the audio signal to which the gain is applied, the lower range component being lower in the frequency than the low range component; and synthesizing an audio signal having an effect sound by adding the audio signal to which the different gains are applied, the higher range component, and the lower range component with each other.

Abstract: An audio signal processing apparatus includes: a first filtering unit which outputs an audio signal while attenuating frequency components except for preset frequency components; a detecting unit which detects a sound volume level; an amplitude limiting unit which calculates an amplitude limiting level corresponding to the sound volume level, and which limits a part of a waveform of the audio signal output from the first filtering unit; a second filtering unit which outputs the audio signal output from the amplitude limiting unit while attenuating frequency components except for preset frequency components including a part of the frequency band of the audio signal output from the first filtering unit, and a part of the frequency band of the harmonics; a compressing unit which compresses a dynamic range of the audio signal; and an adding unit which adds the audio signal output from the compressing unit to the input audio signal.

Abstract: A sound volume controller includes a level adjustment section that adjusts a level of an input audio signal and outputs the adjusted input audio signal as an output audio signal, a level detection section that detects the level of the input audio signal, a volume value detection section that detects a volume value set by a user, a coefficient table storage section that stores a coefficient table which describes a relation between levels of the output audio signal and levels of the input audio signal, a coefficient table change section that changes the coefficient table stored in the coefficient table storage section in accordance with the volume value detected by the volume value detection section, and a setting section that sets an amount of level adjustment of the level adjustment section in accordance with the level of the input audio signal detected by the level detection section and the coefficient table.

Abstract: An effect adding method, includes: applying different gains to a positive side waveform portion and a negative side waveform portion of an audio signal respectively when absolute values of input levels of the positive side waveform portion and the negative side waveform portion are smaller than a predetermined value; producing a higher range component of the audio signal based on a high range component of the audio signal to which the gain is applied, the higher range component being higher in frequency than the high range component; producing a lower range component of the audio signal based on a low range component of the audio signal to which the gain is applied, the lower range component being lower in the frequency than the low range component; and synthesizing an audio signal having an effect sound by adding the audio signal to which the different gains are applied, the higher range component, and the lower range component with each other.

Abstract: LPF and HPF extract bass and treble ranges, respectively, from an input sound signal, and bass and treble boost circuits perform dynamic range expansion/contraction on the extracted bass- and treble-range sound signals in accordance with input levels of the sound signals. The input sound signal and the sound signals output from the boost circuits are added together. There may also be provided coefficient calculation sections for calculating filter coefficients on the basis of the levels of the sound signals extracted by the LPF and HPF. In this case, the bass and treble boost sections perform, in accordance with the filter coefficients calculated by the corresponding coefficient calculation sections, filter processes for increasing/decreasing the levels of the bass and treble ranges, respectively.