Method for generating a surround sound field, apparatus and computer program product thereof
Embodiments of the present invention relate to adaptive audio content generation. Specifically, a method for generating adaptive audio content is provided. The method comprises extracting at least one audio object from channel-based source audio content, and generating the adaptive audio content at least partially based on the at least one audio object. Corresponding system and computer program product are also disclosed.
1. A method of generating a surround sound field, the method comprising:
receiving audio signals captured by a plurality of audio capturing devices;
estimating a topology of the plurality of audio capturing devices; and
generating the surround sound field from the received audio signals at least partially based on the estimated topology,
wherein generating the surround sound field comprises:
applying Ambisonics or B-format processing to the audio signals;
determining a topology template matching the estimated topology of the plurality of audio capturing devices;
selecting weights for the audio signals at least partially based on the determined topology template; and
processing the audio signals using the selected weights to generate the surround sound field.
2. The method according to claim 1 , wherein selecting the weights comprises:
selecting the weights based on the determined topology template and a frequency of the audio signals.
3. The method according to claim 1 , wherein the weights for the audio signals are represented as a mapping matrix for mapping the audio signals to W, X, Y channels of a four channel signal according to the B-format; and
selecting the weights for the audio signals comprises selecting a pre-stored mapping matrix corresponding to the topology template matching the estimated topology of the plurality of audio capturing devices.
4. The method according to claim 1 further comprising:
performing a time alignment of the received audio signals.
5. The method according to claim 4 , wherein performing the time alignment comprises applying at least one of a protocol-based clock synchronization process, a peer-to-peer clock synchronization process, and a cross-correlation process.
6. The method according to claim 1 , further comprising:
converting the generated surround sound field into a target format for playback on a rendering device.
7. An apparatus of generating a surround sound field, the apparatus comprising:
a receiving unit configured to receive audio signals captured by a plurality of audio capturing devices;
a topology estimating unit configured to estimate a topology of the plurality of audio capturing devices; and
a generating unit configured to generate the surround sound field from the received audio signals at least partially based on the estimated topology,
wherein the generating units configured to apply Ambisonics or B-format processing to the audio signals, and comprises:
a template determining unit configured to determine a topology template matching the estimated topology of the plurality of audio capturing devices;
a weight selecting unit configured to select weights for the audio signals at least partially based on the determined topology template; and
a signal processing unit configured to process the audio signals using the selected weights to generate the surround sound field.
8. The apparatus according to claim 7 , wherein the weight selecting unit comprises:
a unit configured to select the weights based on the determined topology template and a frequency of the audio signals.
9. The apparatus according to claim 7 , wherein the weights for the audio signals are represented as a mapping matrix for mapping the audio signals to W, X, Y channels of a four channel signal according to the B-format; and
the weight selecting unit is configured to select a pre-stored mapping matrix corresponding to the topology template matching the estimated topology of the plurality of audio capturing devices.
10. The apparatus according to claim 7 , further comprising:
a time aligning unit configured to perform a time alignment of the received audio signals.
11. The apparatus according to claim 10 , wherein the time aligning unit is configured to apply at least one of a protocol-based clock synchronization process, a peer-to-peer clock synchronization process, and a cross-correlation process.
12. The apparatus according to claim 9 , further comprising:
a converting unit configured to convert the generated surround sound field into a target format for playback on a rendering device.
13. A non-transitory computer-readable medium with instructions stored thereon that when executed by one or more processors configured to carry out the method according to claim 1 .