Sound field forming apparatus and method
Provided is a sound field forming apparatus and method to improve reproducibility of a wave front by using a smaller amount of computation. The sound field forming apparatus includes a listener position acquisition section that acquires listener positional information indicating a position of a listener, a drive speaker selection section that selects one or a plurality of speakers, as a drive speaker, used to form a sound field, among the speakers configuring a speaker array on the basis of the listener positional information, and a drive signal generation section that drives the drive speaker and generates a speaker drive signal for forming the sound field in accordance with a selection result of the drive speaker.
1. A sound field forming apparatus, comprising:
a listener position acquisition section configured to acquire listener positional information indicating a position of a listener;
a drive speaker selection section configured to:
select a first set of speakers of a plurality of speakers, as a drive speaker, based on the listener positional information and information related to a height of a position of an ear of the listener, wherein
the plurality of speakers forms a speaker array,
among the plurality of speakers, the selected first set of speakers is nearest to the listener in a first direction parallel to a second direction in which the plurality of speakers of the speaker array is arrayed, and
a height of one of the selected first set of speakers corresponds to the height of the position of the ear of the listener; and
increase a number of speakers in the first set of speakers selected as the drive speaker, wherein
the increase of the number of speakers is based on an increase in a distance of the listener from the speaker array in a third direction perpendicular to the first direction and the second direction, and
the drive speaker is configured to form a sound field based on a sound wave output from the drive speaker in the third direction perpendicular to the second direction; and
a drive signal generation section configured to:
drive the drive speaker; and
generate a speaker drive signal for the formation of the sound field,
wherein the speaker drive signal is generated based on a selection result of the drive speaker.
2. The sound field forming apparatus according to claim 1 , wherein the sound field is formed by wave front synthesis.
3. The sound field forming apparatus according to claim 1 , wherein the drive signal generation section is further configured to:
convolute a specific filter coefficient of a plurality of filter coefficients and a sound source signal, wherein
each of the plurality of filter coefficients corresponds to one of the plurality of speakers, and
the specific filter coefficient corresponds to a specific speaker of the selected first set of speakers; and
generate the speaker drive signal for the specific speaker of the selected first set of speakers based on the convolution.
4. The sound field forming apparatus according to claim 3 , further comprising a filter coefficient recording section configured to record the plurality of filter coefficients of the plurality of speakers.
5. The sound field forming apparatus according to claim 1 , wherein
the drive speaker selection section is further configured to select a second set of speakers of the plurality of speakers as the drive speaker,
the selected second set of speakers is nearest to a sound source in the first direction parallel to the second direction among the plurality of speakers, and
generation of the sound source is based on the formation of the sound field.
6. The sound field forming apparatus according to claim 1 , wherein
based on an increase in one of a number of listeners or a number of listener groups, the drive speaker selection section is further configured to decrease the number of speakers in the first set of speakers selected as the drive speaker, and
the first set of speakers is selected for one of each listener of the number of listeners or each listener group of the number of listener groups.
7. The sound field forming apparatus according to claim 1 , wherein the drive speaker selection section is further configured to select the drive speaker based on a forming system of the sound field.
8. The sound field forming apparatus according to claim 1 , wherein the drive speaker selection section is further configured to:
determine a number of listeners that exist in a specific listening area with respect to the listener positional information; and
determine the number of speakers based on the number of listeners in the specific listening area.
9. The sound field forming apparatus according to claim 1 , wherein
the speaker array is a planar speaker array, and
the plurality of speakers of the speaker array is arrayed in a planar manner.
10. A sound field forming method, comprising:
in a sound field forming apparatus that includes a listener position acquisition section, a drive speaker selection section, and a drive signal generation section:
acquiring, by the listener position acquisition section, listener positional information indicating a position of a listener;
selecting, by the drive speaker selection section, a set of speakers of a plurality of speakers, as a drive speaker, based on the listener positional information and information related to a height of a position of an ear of the listener, wherein
the plurality of speakers forms a speaker array,
among the plurality of speakers, the selected set of speakers is nearest to the listener in a first direction parallel to a second direction in which the plurality of speakers of the speaker array is arrayed, and
a height of one of the selected set of speakers corresponds to the height of the position of the ear of the listener;
increasing, by the drive speaker selection section, a number of speakers in the set of speakers selected as the drive speaker, wherein
the increase of the number of speakers is based on an increase in a distance of the listener from the speaker array in a third direction perpendicular to the first direction and the second direction;
forming, by the drive speaker, a sound field based on a sound wave output from the drive speaker in the third direction perpendicular to the second direction;
driving the drive speaker by the drive signal generation section; and
generating, by the drive signal generation section, a speaker drive signal for the formation of the sound field,
wherein the speaker drive signal is generated based on a selection result of the drive speaker.
11. A non-transitory computer-readable medium having stored thereon computer-executable instructions which, when executed by a computer, cause the computer to execute operations, the operations comprising:
acquiring listener positional information indicating a position of a listener;
selecting a set of speakers of a plurality of speakers, as a drive speaker, based on the listener positional information and information related to a height of a position of an ear of the listener, wherein
the plurality of speakers forms a speaker array,
among the plurality of speakers, the selected set of speakers is nearest to the listener in a first direction parallel to a second direction in which the plurality of speakers of the speaker array is arrayed, and
a height of one of the selected set of speakers corresponds to the height of the position of the ear of the listener;
increasing a number of speakers in the set of speakers selected as the drive speaker, wherein
the increase of the number of speakers is based on an increase in a distance of the listener from the speaker array in a third direction perpendicular to the first direction and the second direction, and
the drive speaker is configured to form a sound field based on a sound wave output from the drive speaker in the third direction perpendicular to the second direction;
driving the drive speaker; and
generating a speaker driving signal for the formation of the sound field,
wherein the speaker drive signal is generated based on a selection result of the drive speaker.