Slot position coding of residual signals of spatial audio coding application

• US 7,765,104 B2
• Filed: 08/30/2006
• Issued: 07/27/2010
• 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
• Primary Examiner(s): Dorvil; Richemond
• Assistant Examiner(s): GODBOLD, DOUGLAS
• Application Number:
  US11/514,302
• Publication Number:
  US 20070094036A1
• Time in Patent Office: 1,427 Days
• Field of Search: 704200-201, 704/500, 704/501
• US Class Current: 704/500
• 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 method of decoding an audio signal performed by an audio coding system, the audio signal including a downmix signal and spatial information, the spatial information including a residual signal, 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 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; and

decoding the audio signal by using the parameter set including the updated parameter based on the time slot information, wherein the process of extracting time slot information further 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.

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

3. The method 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.

4. An apparatus for decoding an audio signal, the audio signal including a downmix signal and spatial information, the spatial information including a residual signal, comprising:

a processor comprising a signal receiving unit, a spatial information obtaining unit and an upmixing unit,

wherein the signal receiving unit is operable for receiving a residual signal, a downmix signal and spatial information, and

wherein the spatial information obtaining unit is operable for obtaining parameter set, time slot information corresponding to the parameter set and residual band information indicating the number of parameter bands corresponding to the residual signal, and 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

wherein the upmixing unit is operable for decoding the downmix signal by using the parameter set including the updated parameter based on the time slot information,

wherein a bit length of the time slot information is determined based on a number of time slots, a number of parameter sets, and previous time slot information associated with a previous parameter set.

5. The apparatus of claim 4, wherein the time slot information is position information indicating a position of a time slot to which a parameter set is applied.

6. The apparatus of claim 4, 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.