USAC audio signal encoding/decoding apparatus and method for digital radio services
Disclosed is a unified speech and audio coding (USAC) audio signal encoding/decoding apparatus and method for digital radio services. An audio signal encoding method may include receiving an audio signal, determining a coding method for the received audio signal, encoding the audio signal based on the determined coding method, and configuring, as an audio superframe of a fixed size, an audio stream generated as a result of encoding the audio signal, wherein the coding method may include a first coding method associated with extended high-efficiency advanced audio coding (xHE-AAC) and a second coding method associated with existing advanced audio coding (AAC).
1. An audio signal encoding method performed by at least processor comprising:
wherein the processor configured to:
receive an audio signal;
determine a coding method for the received audio signal for each audio superframe of the audio signal; and
encode the audio signal based on the determined coding method for the each audio superframe,
wherein the coding method comprises a first coding method associated with USAC (Unified Speech Audio Coding) and a second coding method associated with existing advanced audio coding (AAC), and
when the coding method is determined as first encoding method, wherein the processor configured to:
perform MPS212 encoding, a tool for the MPS encoding, on the received audio signal;
perform enhanced spectral band replication (eSBR) on an audio signal output from the performing of the MPS212 encoding; and
performing core encoding on an audio signal output from the performing of the eSBR,
when the coding method is determined as second encoding method, wherein the processor configured to:
perform parametric stereo (PS) and spectral band replication (SBR) on the received audio signal; and
performing encoding on an audio signal output from the performing of the PS and SBR using the second coding method.
2. The audio signal encoding method of claim 1 , wherein the processor is configured to:
determine a coding method for the received audio signal by determining whether a type of the received audio signal is a multichannel audio signal or a mono or stereo audio signal; and
perform moving picture experts group (MPEG) surround (MPS) encoding when the received audio signal is determined to be the multichannel audio signal.
3. The audio signal encoding method of claim 1 , wherein the audio superframe comprises a header section comprising information about a number of borders of audio frames comprised in the audio superframe and information about a reservoir fill level of a first audio frame, a payload section comprising bit information of the audio frames comprised in the audio superframe, and a directory section comprising border location information of a bit string for each audio frame comprised in the audio superframe.
4. The audio signal encoding method of claim 1 , wherein the processor is configured to:
apply forward error correction (FEC) to the audio superframe for
correcting a bit error occurring when the audio superframe is being transmitted through a communication line.
5. An audio signal decoding method performed by at least processor comprising:
wherein the processor configured to:
receive an audio signal including an audio superframe;
determine a decoding method for the audio superframe of the audio signal; and
decode the audio superframe based on the determined decoding method for the audio superframe,
wherein the decoding method comprises a first decoding method associated with USAC (Unified Speech Audio Coding) and a second decoding method associated with existing advanced audio coding (AAC), and
when the coding method is determined as first decoding method, wherein the processor configured to:
perform core decoding on the received audio superframe when the decoding method for the received audio superframe is determined to be the first decoding method;
perform enhanced spectral band replication (eSBR) on an audio signal output from the performing of the core decoding; and
perform MPS212 decoding on an audio signal output from the performing of the eSBR,
when the coding method is determined as second decoding method, wherein the processor configured to:
perform decoding on the received audio superframe using the second decoding method; and
perform parametric stereo (PS) and spectral band replication (SBR) on an audio signal output from the performing of the second decoding method.
6. The audio signal decoding method of claim 5 , wherein the processor is configured to:
extract a decoding parameter from the received audio superframe; and
determine at least one decoding method of the first decoding method and the second decoding method based on the extracted decoding parameter.
7. The audio signal decoding method of claim 6 , wherein the decoding parameter is automatically determined based on a user parameter used for encoding the audio signal,
wherein the user parameter comprises at least one of bit rate information of a codec for the audio signal, layout type information of the audio signal, and information as to whether moving picture experts group (MPEG) surround (MPS) encoding is used for the audio signal.
8. The audio signal decoding method of claim 5 , wherein the audio superframe comprises a header section comprising information about a number of borders of audio frames comprised in the audio superframe and information about a reservoir fill level of a first audio frame, a payload section comprising bit information of the audio frames comprised in the audio superframe, and a directory section comprising border location information of a bit string for each audio frame comprised in the audio superframe.
9. An audio signal decoding apparatus comprising:
at least processor configured to:
receive an audio signal including an audio superframe;
determine a decoding method for the audio superframe of the an audio signal; and
decode the audio superframe based on the determined decoding method for the audio superframe,
wherein the decoding method comprises a first decoding method associated with USAC (Unified Speech Audio Coding) and a second decoding method associated with existing advanced audio coding (AAC), and
when the coding method is determined as first decoding method, wherein the processor configured to:
perform core decoding on the received audio superframe when the decoding method for the received audio superframe is determined to be the first decoding method;
perform enhanced spectral band replication (eSBR) on an audio signal output from the performing of the core decoding; and
perform MPS212 decoding on an audio signal output from the performing of the eSBR,
when the coding method is determined as second decoding method, wherein the processor configured to:
perform decoding on the received audio superframe using the second decoding method; and
perform parametric stereo (PS) and spectral band replication (SBR) on an audio signal output from the performing of the second decoding method.
10. The audio signal decoding apparatus of claim 9 , wherein the processor is configured to extract a decoding parameter from the received audio superframe, and determine at least one decoding method of the first decoding method and the second decoding method based on the extracted decoding parameter.
11. The audio signal decoding apparatus of claim 10 , wherein the decoding parameter is automatically determined based on a user parameter used for encoding the audio signal,
wherein the user parameter comprises bit rate information of a codec for the audio signal, layout type information of the audio signal, and information as to whether moving picture experts group (MPEG) surround (MPS) encoding is used for the audio signal.