FIG. 1 is a diagram illustrating a conventional audio service system.
As shown in FIG. 1, the conventional audio service system includes an audio service providing apparatus 10 and an audio service reproducing apparatus 20. The audio service providing apparatus 10 includes an audio-capture unit 11 for capturing an audio signal such as sound, an editing/mixing unit 12 for editing and mixing the captured audio signal to transmit the audio signal to an audio service reproducing apparatus 20, and a storing/transmitting unit 13 for storing the mixed audio signal and transmitting the mixed audio signal to the audio service reproducing apparatus 20.
The audio service reproducing apparatus 20 includes a receiver 21 for receiving an audio signal transmitted from the audio service providing apparatus 10, a controller 22 for controlling the received audio signal, and a reproducer 23 for reproducing an audio signal.
An audio signal, which is provided through broadcasting services such as TV broadcasting, radio broadcasting, and Digital Multimedia Broadcasting (DMB) based on the conventional audio service system, is generally created by mixing a plurality of audio signals captured from various sound sources. For example, an audio signal provided through a soccer game broadcasting is created by mixing noises in a soccer stadium, yelling of a crowd, and a voice of an announcer.
Although a user or a viewer can control the volume of the overall audio signal, it is impossible to control the volume of each object such as the voice of an announcer, the yelling of a crowd, and the noises of the soccer stadium. It is because the audio signal is transmitted after a plurality of object audio signals are mixed into one audio signal in a general broadcasting service.
However, if a transmitter such as the audio service providing apparatus 10 independently transmits object audio signals of the sound sources without the object audio signals of the sound sources mixed to one audio signal, a receiver such as the audio service reproducing apparatus 20 can independently control the volumes of the object audio signals of the sound sources. An object-based audio service denotes such an audio service that allows a user or a viewer to control each of the object audio signals at a receiver by independently transmitting the object audio signals of the sound sources through a transmitter.
For example, if an audio signal of a soccer game broadcasting is provided based on an object-based 3-D audio service, a user or a viewer can control each of objects, such as the noises in the soccer stadium, the yelling of the crowd, and the voices of an announcer to obtain a desired audio setting. That is, a user or a viewer can control the noise of the soccer stadium loud, the yelling of the crowd soft, and the voice of the announcer loud. Or, a viewer can control the audio signal to reproduce only the noises of the soccer stadium and the voice of an announcer without the yelling of the crowd reproduced.
Therefore, there is a great demand for developing a method for providing an object-based 3-D audio service that enables a user to control each of object audio signals of sound sources, which can be applied to all broadcasting services and multimedia services providing audio such as digital broadcasting, radio broadcasting, Digital Multimedia Broadcasting, Internet broadcasting, digital movie, DVD, moving picture contents.
Although a conventional object-based 3-D audio system and a control method thereof was introduced in Korean Patent Publication No. 10-2004-0037437, published on May 7, 2004, the conventional object-based 3-D audio system requires a user to control each of object audio signals of sound sources to set the audio signals according to user's preference. Therefore, it is very annoying to a user or a viewer.