METHOD OF COMPENSATING FOR AUDIO FREQUENCY CHARACTERISTICS AND AUDIO/VIDEO APPARATUS USING THE METHOD

• US 20090196428A1
• Filed: 07/29/2008
• Published: 08/06/2009
• Est. Priority Date: 01/31/2008
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: KIM, Jong-bae
• Granted Patent: US 8,290,185 B2
• Time in Patent Office: Days
• US Class Current: 381/17
• CPC Class Codes: H04R 2499/15 Transducers incorporated in visual displaying devices, e.g. televisions, computer displays, laptops
• CPC Class Codes: H04R 3/04 for correcting frequency response
• CPC Class Codes: H04S 7/302 Electronic adaptation of stereophonic sound system to listener position or orientation H04S7/301 takes precedence

Abstract

A method of compensating for spatial audio frequency characteristics that varies in accordance with a mounting condition of a down firing speaker of an audio/video (AV) apparatus includes calculating a listening distance between the AV apparatus and a listener, calculating a distance between a speaker mounted on the AV apparatus and a neighboring reflective surface, setting a spatial frequency compensation filter value and a speaker frequency characteristic compensation filter value based on the calculated distances, and compensating for frequency characteristics of an audio signal by combining the spatial frequency compensation filter value and the speaker frequency characteristic compensation filter value.

Claims

1. A method of compensating for audio frequency characteristics of an audio/video (AV) apparatus, the method comprising:

calculating a listening distance between the AV apparatus and a listener;

calculating a distance between a speaker mounted on the AV apparatus and a neighboring reflective surface;

setting a spatial frequency compensation filter value and a speaker frequency characteristic compensation filter value based on the calculated distances; and

compensating for frequency characteristics of an audio signal by combining the spatial frequency compensation filter value and the speaker frequency characteristic compensation filter value.

2. The method of claim 1, wherein the speaker has a down firing structure, and is mounted on a lower portion of the AV apparatus, and a diaphragm of the speaker faces downward.

3. The method of claim 1, wherein the calculating of the distance between the speaker mounted on the AV apparatus and the neighboring reflective surface comprises:

calculating a distance between each channel speaker mounted on the AV apparatus and a neighboring wall or floor.

4. The method of claim 1, wherein the calculating of the distance between the speaker mounted on the AV apparatus and the neighboring reflective surface comprises:

calculating a distance between each channel speaker mounted on the AV apparatus and the neighboring reflective surface by using ultrasonic waves.

5. The method of claim 1, wherein each of the distances is calculated based on distance information that is input by the user through a user interface (UI).

6. The method of claim 1, wherein the setting of the spatial frequency compensation filter value and the speaker frequency characteristic compensation filter value comprises:

if a distance between each channel speaker and a neighboring reflective surface thereof is larger than a predetermined threshold value, setting the spatial frequency compensation filter value and the speaker frequency characteristic compensation filter value which are differently set in accordance with channels and distances; and

if the distance between each channel speaker and a neighboring reflective surface thereof is equal to or smaller than the predetermined threshold value, setting the spatial frequency compensation filter value and the speaker frequency characteristic compensation filter value which are commonly set in accordance with distances.

7. The method of claim 1, wherein the setting of the spatial frequency compensation filter value and the speaker frequency characteristic compensation filter value comprises:

if a difference between a distance between a left channel speaker and a neighboring reflective surface thereof and the distance between a right channel speaker and a neighboring reflective surface thereof is larger than a predetermined threshold value, setting the spatial frequency compensation filter value and the speaker frequency characteristic compensation filter value which are differently set in accordance with channels and distances; and

if the difference between the distance between the left channel speaker and a neighboring reflective surface thereof and the distance between the right channel speaker and a neighboring reflective surface thereof is equal to or smaller than the predetermined threshold value, setting the spatial frequency compensation filter value and the speaker frequency characteristic compensation filter value which are commonly set in accordance with distances.

8. The method of claim 1, wherein the spatial frequency compensation filter value and the speaker frequency characteristic compensation filter value are respectively selected from spatial frequency compensation filter values which are preset in accordance with distances and speaker frequency characteristic compensation filter values which are set in default.

9. The method of claim 1, wherein the speaker frequency characteristic compensation filter value compensates a high band that is damped when the speaker is down-fired.

10. The method of claim 1, wherein the spatial frequency compensation filter value compensates for frequency characteristics which vary in accordance with a mounting condition of the speaker having a down firing structure.

11. An audio/video (AV) apparatus, comprising:

channel speaker units to output audio signals;

a control unit to extract information on a listening distance between the AV apparatus and a listener, and information on a distance between each of the channel speaker units and a respective neighboring reflective surface thereof, and to set a spatial frequency compensation filter and a speaker frequency characteristic compensation filter of each of the channel speaker units, based on the extracted information; and

an audio frequency compensation unit to compensate for frequency characteristics of an audio signal by combining the spatial frequency compensation filter and the speaker frequency characteristic compensation filter which are set by the control unit.

12. The AV apparatus of claim 11, wherein the channel speaker units are mounted on the AV apparatus or a wall mount speaker apparatus, and are disposed at a predetermined angle off-axis position from the listener so as not to be seen from a front side of the AV apparatus.

13. The AV apparatus of claim 11, further comprising:

a storage unit to store spatial frequency compensation filter values which are preset in accordance with distances and speaker frequency characteristic compensation filter values which are set in default.

14. The AV apparatus of claim 11, wherein the speaker frequency characteristic compensation filter compensates a high band that is damped when each of the channel speaker units is down-fired.

15. The AV apparatus of claim 11, wherein the spatial frequency compensation filter compensates for frequency characteristics which vary in accordance with a mounting condition of each of the channel speaker units having a down firing structure.

16. The AV apparatus of claim 11, wherein each of the spatial frequency compensation filter and the speaker frequency characteristic compensation filter is a finite impulse response (FIR) filter or an infinite impulse response (IIR) filter.

17. The AV apparatus of claim 11, further comprising:

a user interface (UI) through which distance information is exchanged between the AV apparatus and the user,

wherein the UI inputs the information on the listening distance between the AV apparatus and the listener, and the distance between each of the channel speaker units and a neighboring reflective surface thereof, which are defined by the user, to the AV apparatus.

18. A computer readable recording medium having embodied thereon a computer program to execute a method, wherein the method comprises:

calculating a listening distance between an audio/video (AV) apparatus and a listener;

calculating a distance between a speaker mounted on the AV apparatus and a neighboring reflective surface;

setting a spatial frequency compensation filter value and a speaker frequency characteristic compensation filter value based on the calculated distances; and

compensating for frequency characteristics of an audio signal by combining the spatial frequency compensation filter value and the speaker frequency characteristic compensation filter value.

19. An audio/video (AV) apparatus, comprising:

a channel speaker unit including one or more of a spatial frequency compensation filter and a speaker frequency characteristic compensation filter, and disposed at a predetermined angle off-axis position from a listener; and

a control unit to extract information on at least one of a listening distance between the AV apparatus and the listener, and a surface distance between the channel speaker unit and a neighboring reflective surface thereof,

wherein the control unit sets, based on the extracted information, the one or more of the spatial frequency compensation filter to compensate for frequency characteristics which vary in accordance with a mounting condition of the channel speaker unit and a speaker frequency characteristic compensation filter to compensate for a high band based on the extracted information.

20. The AV apparatus of claim 19, wherein the predetermined angle is substantially 90 degrees.

21. The AV apparatus of claim 20, wherein the channel speaker unit is disposed at a predetermined angle off-axis position from a listener to prevent the listener from viewing the channel speaker unit from a front side of the AV apparatus.

22. A method of operating an audio/video (AV) apparatus, the method comprising:

extracting information on at least one of a listening distance between an AV apparatus and a listener, and a surface distance between a channel speaker unit disposed at a predetermined angle off-axis position from the listener and a neighboring reflective surface thereof, and

setting, based on the extracted information, one or more of a spatial frequency compensation filter to compensate for frequency characteristics which vary in accordance with a mounting condition of the channel speaker unit and a speaker frequency characteristic compensation filter to compensate for a high band based on the extracted information.