Sound processing apparatus, sound processing method, and sound processing program

1. A sound processing apparatus comprising:

a first sound collecting unit placed in a sound field and configured to collect a sound signal which is speech of a talker;

a second sound collecting unit arranged to be movable to a position which is closer to the talker than the first sound collecting unit and configured to collect the sound signal;

a transfer function estimating unit configured to estimate a transfer function in the sound field from a sound signal collected by the first sound collecting unit and a sound signal collected by the second sound collecting unit when the talker is at a predetermined position in the sound field; and

a sound signal processing unit configured to perform a process of the sound signal by use of the transfer function estimated by the transfer function estimating unit, wherein

the first sound collecting unit is arranged at a position where a direct or reflected sound of the talker can be collected, and

the second sound collecting unit is arranged at a position where a direct sound of the talker can be collected.

2. The sound processing apparatus according to claim 1 , further comprising:

a storage unit configured to store the transfer function estimated by the transfer function estimating unit; and

a talker identifying unit configured to identify the talker, wherein

the transfer function estimating unit selects, when the transfer function of the talker identified by the talker identifying unit is stored in the storage unit, the transfer function which corresponds to the talker and is stored in the storage unit.

3. The sound processing apparatus according to claim 2 , wherein

the transfer function estimating unit performs notification which prompts the talker to utter when the transfer function of the talker identified by the talker identifying unit is not stored in the storage unit.

4. The sound processing apparatus according to claim 1 , wherein

the first sound collecting unit collects a sound signal when the talker utters, and

the transfer function estimating unit sequentially updates the transfer function based on the sound signal collected by the first sound collecting unit.

5. The sound processing apparatus according to claim 1 , further comprising:

a storage unit configured to preliminarily store a predetermined transfer function, wherein

the transfer function estimating unit interpolates the transfer function stored preliminarily in the storage unit by use of the transfer function estimated based on the sound signal collected by the first sound collecting unit and the sound signal collected by the second sound collecting unit.

6. A sound processing apparatus comprising:

a first sound collecting unit placed in a sound field and configured to collect a sound signal which is speech of a talker;

a talker position estimating unit configured to estimate a talker position which is a position of the talker relative to the first sound collecting unit;

a transfer function estimating unit configured to estimate a transfer function in the sound field from the estimated talker position and a sound signal collected by the first sound collecting unit when the talker is at a predetermined position in the sound field; and

a sound signal processing unit configured to perform a process of the sound signal by use of the transfer function estimated by the transfer function estimating unit, wherein

the first sound collecting unit is arranged at a position where a direct or reflected sound of the talker can be collected.

7. A sound processing apparatus comprising:

a first sound collecting unit placed in a sound field and configured to collect a sound signal which is speech of a talker, by use of a plurality of microphones;

a delaying unit configured to delay all sound signals collected by the first sound collecting unit when the talker is at a predetermined position in the sound field, by a predetermined time;

a selecting unit configured to select one microphone of the plurality of microphones;

a transfer function estimating unit configured to estimate a transfer function of another microphone relative to the selected one microphone in the sound field by use of a sound signal delayed by the delaying unit; and

a sound signal processing unit configured to perform a process of the sound signal by use of the transfer function estimated by the transfer function estimating unit, wherein

the first sound collecting unit is arranged at a position where a direct or reflected sound of the talker can be collected.

8. A sound processing method comprising:

(a) by way of a first sound collecting unit placed in a sound field, collecting a sound signal which is speech of a talker;

(b) by way of a second sound collecting unit arranged to be movable to a position which is closer to the talker than the first sound collecting unit, collecting the sound signal;

(c) by way of a transfer function estimating unit, estimating a transfer function in the sound field from a sound signal collected in the step (a) and a sound signal collected in the step (b) when the talker is at a predetermined position in the sound field; and

(d) by way of a sound signal processing unit, performing a process of the sound signal by use of the transfer function estimated in the step (c), wherein

the first sound collecting unit is arranged at a position where a direct or reflected sound of the talker can be collected, and

the second sound collecting unit is arranged at a position where a direct sound of the talker can be collected.

9. A sound processing method comprising:

(a) by way of a first sound collecting unit placed in a sound field, collecting a sound signal which is speech of a talker, by use of a plurality of microphones;

(b) by way of a delaying unit, delaying all sound signals collected in the step (a) when the talker is at a predetermined position in the sound field, by a predetermined time;

(c) by way of a selecting unit, selecting one microphone of the plurality of microphones;

(d) by way of a transfer function estimating unit, estimating a transfer function of another microphone relative to the one microphone selected in the step (c) in the sound field by use of a sound signal delayed in the step (b); and

(e) by way of a sound signal processing unit, performing a process of the sound signal by use of the transfer function estimated in the step (d), wherein

the first sound collecting unit is arranged at a position where a direct or reflected sound of the talker can be collected.

10. A non-transitory computer-readable recording medium comprising a sound processing program causing a computer of a sound processing apparatus including a first sound collecting unit placed in a sound field and a second sound collecting unit arranged to be movable to a position which is closer to a talker than the first sound collecting unit to perform:

(a) by way of the first sound collecting unit, collecting a sound signal which is speech of the talker;

(b) by way of the second sound collecting unit, collecting the sound signal;

(c) estimating a transfer function in the sound field from a sound signal collected in the step (a) and a sound signal collected in the step (b) when the talker is at a predetermined position in the sound field; and

(d) performing a process of the sound signal by use of the transfer function estimated in the step (c), wherein

the first sound collecting unit is arranged at a position where a direct or reflected sound of the talker can be collected, and

the second sound collecting unit is arranged at a position where a direct sound of the talker can be collected.

11. A non-transitory computer-readable recording medium comprising a sound processing program causing a computer of a sound processing apparatus including a first sound collecting unit placed in a sound field to perform:

(a) by way of the first sound collecting unit, collecting a sound signal which is speech of a talker, by use of a plurality of microphones;

(b) delaying all sound signals collected in the step (a) when the talker is at a predetermined position in the sound field, by a predetermined time;

(c) selecting one microphone of the plurality of microphones;

(d) estimating a transfer function of another microphone relative to the one microphone selected in the step (c) in the sound field by use of a sound signal delayed in the step (b); and

(e) performing a process of the sound signal by use of the transfer function estimated in the step (d), wherein

the first sound collecting unit is arranged at a position where a direct or reflected sound of the talker can be collected.