Method for processing and reproducing audio signal at desired sound quality, reduced data volume or adjusted output level, apparatus for processing audio signal with sound quality control information or test tone signal or at reduced data volume, recording medium for recording audio signal with sound quality control information or test tone signal or at reduced data volume, and apparatus for reproducing audio signal at desired sound quality, reduced data volume or adjusted output level

An audio signal reproducing apparatus for reproducing an analog audio signal from packed data composed of a series of audio data, which is obtained by converting the analog audio signal of a channel, and a plurality of pieces of sound quality control information, which each denote information for adjusting a sound quality of a music indicated by the analog audio signal, comprising:

• audio signal decoding means for decoding the packed data to reproduce the series of audio data and the pieces of sound quality control information;
• operating means for receiving a user's instruction requesting the selection of a piece of particular sound quality control information from the pieces of sound quality control information reproduced by the audio signal decoding means;
• selecting means for selecting the piece of particular sound quality control information according to the user's instruction received by the operating means;
• signal processing means for adjusting levels of the pieces of audio data reproduced by the audio signal decoding means according to the piece of particular sound quality control information selected by the selecting means to produce a series of sound quality adjusted audio data;
• and
• audio data outputting means for outputting the series of sound quality adjusted audio data produced by the signal processing means.

An audio signal processing and reproducing method, comprising the steps of:

• converting an analog audio signal of a channel into a digital audio signal composed of a plurality of pieces of audio data;
• shifting original levels of the pieces of audio data of the digital audio signal by a particular differential level to produce a level-shifted digital audio signal composed of a plurality of pieces of level-shifted audio data having shifted levels;
• producing level shift control data indicating the particular differential level;
• transmitting or recording the level-shifted digital audio signal and the level shift control data;
• returning the shifted levels of the pieces of level-shifted audio data of the level-shifted digital audio signal transmitted or recorded to the original levels according to the level shift control data transmitted or recorded with the level-shifted digital audio signal to reproduce the pieces of audio data of the digital audio signal having the original levels;
• and
• outputting the digital audio signal.

An audio signal processing apparatus, comprising:

• analog-digital converting means for converting an analog audio signal of a channel into a plurality of pieces of audio data of a digital audio signal;
• level shifting means for shifting original levels of the pieces of audio data of the digital audio signal obtained by the analog-digital converting means by a particular differential level to produce a plurality of pieces of level-shifted audio data of a level-shifted digital audio signal having shifted levels;
• level shift control data producing means for producing level shift control data indicating the particular differential level;
• and
• audio signal coding means for coding a set of the pieces of level-shifted audio data obtained by the level shifting means and the level shift control data produced by the level shift control data producing means to produce packed data, the packed data being transmitted or recorded.

An audio signal processing and reproducing method, comprising the steps of:

• converting a series of analog audio signals, into which a test tone signal is inserted, into a series of digital audio signals including a test tone digital signal obtained by converting the test tone signal;
• arranging each of the digital audio signals in an audio pack;
• arranging the test tone digital signal in a test tone audio pack to produce a series of audio packs including the test tone audio pack;
• dividing the series of audio packs including the test tone audio pack into a plurality of groups of audio packs;
• allocating an audio control pack, in which control information is arranged, to each group of audio packs to set the control information and one group of digital audio signals arranged in one group of audio packs as packed data;
• adding mute control information indicating the performance of a mute control to the control information of one piece of packed data in cases where the test tone digital signal is included in the piece of packed data;
• recording the pieces of packed data;
• reading out the pieces of packed data;
• decoding the pieces of packed data to reproduce the control information and one group of digital audio signals from each piece of packed data, the mute control information being reproduced from one piece of packed data in which the test tone digital signal is included;
• adjusting levels of the digital audio signals reproduced from the pieces of packed data according to the test tone digital signal;
• outputting a sound indicated by one group of digital audio signals reproduced from one piece of packed data for each piece of packed data in cases where any mute control information is not included in the control information of the packed data;
• and
• muting a sound of one group of digital audio signals reproduced from one piece of packed data according to the mute control in cases where the mute control information is included in the control information of the packed data.

An audio signal recording medium, comprising:

• a plurality of first data areas for respectively recording a series of first packed data obtained by converting a plurality of analog audio signals, into which a test tone signal is inserted, into a plurality of digital audio signals, arranging each of the digital audio signals in an audio pack, dividing the audio packs into a plurality of groups of audio packs, allocating a first audio control pack, in which control information indicating the control of the digital audio signals is arranged, to each group of audio packs to set the control information and one group of digital audio signals as one series of first packed data;
• and
• a second data area for recording a series of second packed data obtained by converting a test tone signal inserted into the plurality of analog audio signals into a test tone digital signal, arranging the test tone digital signal in a test tone audio pack and allocating a second audio control pack, in which control information indicating the control of the digital audio signals and mute control information indicating the performance of a mute control are arranged, to the test tone audio pack and one or more audio packs relating to one or more digital audio signals obtained from one or more analog audio signals adjacent to the test tone signal to set the control information, the mute control information and the digital audio signals as the series of second packed data, a sound of digital audio signals being muted according to the mute control in cases where the series of second packed data is reproduced.

An audio signal reproducing apparatus for reproducing a series of analog audio signals, into which a test tone signal is inserted, from a series of packed data, which are obtained by converting the series of analog audio signals into a series of digital audio signals, converting the test tone signal into a test tone digital signal, arranging each of the digital audio signals in an audio pack, arranging the test tone digital signal in a test tone audio pack to produce a series of audio packs including the test tone audio pack, dividing the series of audio packs including the test tone audio pack into a plurality of groups of audio packs, allocating an audio control pack, in which control information is arranged, to each group of audio packs to set the control information and one group of digital audio signals arranged in one group of audio packs as packed data, and adding mute control information indicating the performance of a mute control to the control information of one piece of packed data in cases where the test tone digital signal is included in the piece of packed data, comprising:

• audio signal decoding means for decoding the pieces of packed data to reproduce the control information and one group of digital audio signals for each piece of packed data, the mute control information being reproduced from one piece of packed data in which the test tone digital signal is included;
• signal processing means for adjusting levels of the digital audio signals reproduced from the pieces of packed data by the audio signal decoding means according to the test tone digital signal;
• control means for judging for each piece of control information whether or not the mute control information is included in the control information reproduced by the audio signal decoding means and outputting a mute control instruction to perform the mute control for a particular group of digital audio signals of a piece of particular packed data in cases where the mute control information is included in the control information of the piece of particular packed data;
• and
• mute control performing means for performing the mute control to mute an output sound of the particular group of digital audio signals according to the mute control instruction output from the control means and outputting a sound of the groups of digital audio signals other than the particular group of digital audio signals.