SLOT POSITION CODING OF RESIDUAL SIGNALS OF SPATIAL AUDIO CODING APPLICATION

• US 20110044458A1
• Filed: 07/26/2010
• Published: 02/24/2011
• Est. Priority Date: 08/30/2005
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Pang, Hee Suk, Oh, Hyen O., Lim, Jae Hyun, Jung, Yang Won, Kim, Dong Soo
• Granted Patent: US 8,060,374 B2
• Time in Patent Office: Days
• US Class Current: 381/22
• CPC Class Codes: G10L 19/008 Multichannel audio signal coding or decoding using interchannel correlation to reduce redundancy, e.g. joint-stereo, intensity-coding or matrixing
• CPC Class Codes: G10L 19/167 Audio streaming, i.e. formatting and decoding of an encoded audio signal representation into a data stream for transmission or storage purposes
• CPC Class Codes: H04R 2499/11 Transducers incorporated or for use in hand-held devices, e.g. mobile phones, PDA's, camera's
• CPC Class Codes: H04S 1/007 in which the audio signals are in digital form data reduction aspects thereof based on psychoacoustics G10L19/02
• CPC Class Codes: H04S 2420/03 Application of parametric coding in stereophonic audio systems
• CPC Class Codes: H04S 3/002 Non-adaptive circuits, e.g. manually adjustable or static, for enhancing the sound image or the spatial distribution control circuits for electronic adaptation of the sound field H04S7/30

Abstract

Spatial information associated with an audio signal is encoded into a bitstream, which can be transmitted to a decoder or recorded to a storage media. The bitstream can include different syntax related to time, frequency and spatial domains. In some embodiments, the bitstream includes one or more data structures (e.g., frames) that contain ordered sets of slots for which parameters can be applied. The data structures can be fixed or variable. The data structure can include position information that can be used by a decoder to identify the correct slot for which a given parameter set is applied. The slot position information can be encoded with either a fixed number of bits or a variable number of bits based on the data structure type.

Claims

1. A music player, comprising:

an application unit configured to store an audio codec for decoding;

a processor configured to perform operations of generating a multi-channel audio signal from an audio signal, the operations comprising;

extracting time slot information in a variable bit length and residual band information in a fixed bit length, the time slot information indicating a time slot to which a parameter set is applied and the residual band information indicating a number of parameter bands to which a residual signal is applied;

updating a parameter of the parameter set by using the residual signal based on the residual band information, the parameter set including inter-channel correlation information;

converting the audio signal into the multi-channel audio signal by using the parameter set including the updated parameter based on the time slot information,

wherein extracting the time slot information comprises;

extracting a number of time slots and a number of parameter sets from the audio signal to identify time slot information;

determining a bit length of the time slot information, the bit length being variable according to the number of time slots, the number of parameter sets, and previous time slot information associated with a previous parameter set; and

extracting the time slot information based on the bit length,

wherein a number of the time slot information is equal to the number of parameter sets;

a network interface configured to transmit the multi-channel audio signal or the audio signal to an external unit;

an audio subsystem configured to convert the multi-channel audio signal into a multi-channel analog output signal; and

a speaker configured to output at least one channel of the multi-channel analog output signal.

2. The music player of claim 1, wherein at least two of the application unit, the processor, the network interface, the audio subsystem, and the speaker exchange data via one or more buses.

3. The music player of claim 1, wherein the time slot information is position information indicating a position of time slot to which the parameter set is applied.

4. The music player of claim 1, wherein the time slot information includes an absolute value for indicating a time slot to which a first parameter set is applied or a difference value for

indicating a time slot to which a following parameter set of the first parameter set is applied, and

wherein the time slot to which the following parameter set is applied is determined by adding the difference value to the previous time slot information.

5. A broadcast playback system, comprising:

a receiver configured to receive a broadcast signal including an audio signal generated by downmixing a multi-channel audio signal;

a processor configured to perform operations of generating the multi-channel audio signal from the audio signal, the operations comprising;

extracting time slot information in variable bit length and residual band information in fixed bit length, the time slot information indicating a time slot to which a parameter set is applied and the residual band information indicating a number of parameter bands to which a residual signal is applied;

updating a parameter of the parameter set by using the residual signal based on the residual band information, the parameter set including inter-channel correlation information; and

converting the audio signal into the multi-channel audio signal by using the parameter set including the updated parameter based on the time slot information,

wherein extracting the time slot information comprises;

extracting a number of time slots and a number of parameter sets from the audio signal to identify time slot information;

determining a bit length of the time slot information, the bit length being variable according to the number of time slots, the number of parameter sets and previous time slot information associated with a previous parameter set; and

extracting the time slot information based on the bit length,

wherein a number of the time slot information is equal to the number of parameter sets;

an operating system configured to control information regarding transmission of the multi-channel audio signal to an audio subsystem;

a display unit configured to display information regarding the multi-channel audio signal;

an audio subsystem configured to convert the multi-channel audio signal into a multi-channel analog output signal; and

a speaker configured to output at least one channel of the multi-channel analog output signal.

6. The broadcast playback system of claim 5, wherein at least two of the receiver, the processor, the operating system, the display unit, the audio subsystem, and the speaker exchange data via one or more buses.

7. The broadcast playback system of claim 5, wherein the time slot information is position information indicating a position of time slot to which a parameter set is applied.

8. The broadcast playback system of claim 5, wherein the time slot information includes an absolute value for indicating a time slot to which a first parameter set is applied or a difference value for indicating a time slot to which a following parameter set of the first parameter set is applied, and

wherein the time slot to which the following parameter set is applied is determined by adding the difference value to the previous time slot information.

9. A method of decoding an audio signal performed by a music player, the audio signal including a downmix signal and spatial information, the spatial information including a residual signal, the decoding based on audio codec for decoding stored in the music player, the method comprising:

receiving an audio signal including at least one frame, the frame comprising at least one time slot and at least one parameter set;

extracting time slot information in a variable bit length and residual band information in a fixed bit length, the time slot information indicating a time slot to which a parameter set is applied and the residual band information indicating a number of parameter bands to which the residual signal is applied;

updating a parameter of the parameter set using the residual signal based on the residual band information, the parameter set including inter-channel correlation information;

converting the audio signal into a multi-channel audio signal using the parameter set including the updated parameter based on the time slot information,

wherein extracting the time slot information comprises;

extracting a number of time slots and a number of parameter sets from the audio signal to identify time slot information;

determining a bit length of the time slot information, the bit length being variable according to the number of time slots, the number of parameter sets and previous time slot information associated with a previous parameter set; and

extracting the time slot information based on the bit length,

wherein a number of the time slot information is equal to the number of parameter sets;

transmitting the multi-channel audio signal or the audio signal to an external unit;

converting the multi-channel audio signal into a multi-channel analog audio signal;

and outputting at least one channel of the multi-channel analog audio signal.

10. The method of claim 9, wherein the time slot information is position information indicating a position of time slot to which the parameter set is applied.

11. The method of claim 9, wherein the time slot information includes an absolute value for indicating a time slot to which a first parameter set is applied or a difference value for indicating a time slot to which a following parameter set of the first parameter set is applied, and

wherein the time slot to which the following parameter set is applied is determined by adding the difference value to the previous time slot information.

12. A method of decoding an audio signal performed by a broadcast playback system, the audio signal including a downmix signal and spatial information, the spatial information including a residual signal, the method comprising:

receiving an audio signal including at least one frame, the frame comprising at least one time slot and at least one parameter set;

extracting time slot information in a variable bit length and residual band information in a fixed bit length, the time slot information indicating a time slot to which a parameter set is applied and the residual band information indicating a number of parameter bands to which the residual signal is applied;

updating a parameter of the parameter set by using the residual signal based on the residual band information, the parameter set including inter-channel correlation information;

converting the audio signal into a multi-channel audio signal by using the parameter set including the updated parameter based on the time slot information,

wherein extracting the time slot information comprises;

extracting a number of time slots and a number of parameter sets from the audio signal to identify time slot information;

determining a bit length of the time slot information, the bit length being variable according to the number of time slots, the number of parameter sets and previous time slot information associated with a previous parameter set; and

extracting the time slot information based on the bit length,

wherein a number of the time slot information is equal to the number of parameter sets;

sending the multi-channel audio signal to an audio subsystem for converting the multi-channel audio signal, based on information regarding transmission of the multi-channel audio signal;

displaying information regarding the multi-channel audio signal;

converting the multi-channel audio signal into a multi-channel analog audio signal; and

outputting at least one channel of the multi-channel analog audio signal.

13. The method of claim 12, wherein the time slot information is position information indicating a position of time slot to which the parameter set is applied.

14. The method of claim 12, wherein the time slot information includes an absolute value for indicating a time slot to which a first parameter set is applied or a difference value for indicating a time slot to which a following parameter set of the first parameter set is applied, and

wherein the time slot to which the following parameter set is applied is determined by adding the difference value to the previous time slot information.