Signal processing apparatus, signal processing method, and computer program

• US 20080086313A1
• Filed: 09/25/2007
• Published: 04/10/2008
• Est. Priority Date: 10/02/2006
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Tanaka, Mamoru, Tanaka, Mitsunori, Mitsuno, Makoto, Ohta, Masashi
• Granted Patent: US 8,719,040 B2
• Time in Patent Office: Days
• US Class Current: 704/500
• CPC Class Codes: G10L 19/173 Transcoding, i.e. converting between two coded representations avoiding cascaded coding-decoding

Abstract

A signal processing apparatus may include a decoder that decodes a compressed audio stream encoded by a predetermined codec, a signal processing unit that applies predetermined signal processing to an audio stream obtained by decoding the compressed audio stream with the decoder, a first acquisition unit that acquires at least one of information described in a header of the compressed audio stream and management information for contents including the compressed audio stream, a setting unit that discriminates, on the basis of the information, a type of the codec used for the encode of the compressed audio stream and sets a codec used for encode of the audio stream, and an encoder that encodes, in accordance with the setting by the setting unit, the audio stream subjected to the signal processing by the signal processing unit and outputs the audio stream to an external apparatus that has a decoder.

Claims

1. A signal processing apparatus comprising:

a decoder that decodes a compressed audio stream encoded by a predetermined codec;

a signal processing unit that applies predetermined signal processing to an audio stream obtained by decoding the compressed audio stream with the decoder;

a first acquisition unit that acquires at least one of information described in a header of the compressed audio stream and management information for contents including the compressed audio stream;

a setting unit that discriminates, on the basis of the information acquired by the first acquisition unit, a type of the codec used for the encode of the compressed audio stream and sets a codec used for encode of the audio stream subjected to the signal processing by the signal processing unit; and

an encoder that encodes, in accordance with the setting by the setting unit, the audio stream subjected to the signal processing by the signal processing unit and outputs the audio stream to an external apparatus that has a decoder.

2. A signal processing apparatus according to claim 1, wherein the signal processing unit applies signal processing for changing an audio stream to a stream, in which audio combined with other audio is outputted, to the audio stream obtained by decoding the compressed audio stream with the decoder.

3. A signal processing apparatus according to claim 1, wherein the setting unit sets the encoder such that the encode of the audio stream subjected to the signal processing by the signal processing unit is performed by a codec of a type same as that of the codec used for the encode of the compressed audio stream.

4. A signal processing apparatus according to claim 1, wherein when the encoder is not applicable to encode in the codec of the type same as that of the codec used for the encode of the compressed audio stream, the setting unit sets the encoder such that the encode of the audio stream subjected to the signal processing by the signal processing unit is performed by a compatible codec, which is a higher-order codec obtained by extending a function of the codec used for the encode of the compressed audio stream or a lower-order codec obtained by reducing the function.

5. A signal processing apparatus according to claim 1, further comprising a second acquisition unit that acquires information on the external apparatus, wherein the setting unit sets the encoder such that the encode of the audio stream subjected to the signal processing by the signal processing unit is performed by a codec of a type same as that of the codec used for the encode of the compressed audio stream, and a codec of a type same as that of a codec, which is indicated by the information acquired by the second acquisition unit and in which the decoder of the external apparatus is applicable to the decode.

6. A signal processing apparatus according to claim 5, wherein when the encoder is not applicable to the encode in the codec of the type same as that of the codec used for the encode of the compressed audio stream, the setting unit sets the encoder such that the encode of the audio stream subjected to the signal processing by the signal processing unit is performed by a compatible codec, which is a higher-order codec obtained by extending a function of the codec used for the encode of the compressed audio stream or a lower-order codec obtained by reducing the function.

7. A signal processing apparatus according to claim 6, wherein when the encoder is not applicable to the encode in the compatible codec, the setting unit further sets, the encoder such that the encode of the audio stream subjected to the signal processing by the signal processing unit is performed by a codec of a type same as codec in which the decoder of the external apparatus is applicable to the decode.

8. A signal processing apparatus according to claim 1, wherein the first acquisition unit further acquires parameters used for the encode of the compressed audio stream, and the setting unit sets the encoder such that the encode of the audio stream subjected to the signal processing by the signal processing unit is performed in accordance with parameters same as the parameters acquired by the first acquisition unit.

9. A signal processing method comprising:

decoding a compressed audio stream encoded by a predetermined codec;

applying predetermined signal processing to an audio stream obtained by decoding the compressed audio stream;

acquiring at least one of information described in a header of the compressed audio stream and management information for contents including the compressed audio stream;

discriminating, on the basis of the acquired information, a type of the codec used for the encode of the compressed audio stream and setting a codec used for encode of the audio stream subjected to the signal processing; and

encoding, in accordance with the setting, the audio stream subjected to the signal processing and outputting the audio stream to an external apparatus that has a decoder.

10. A signal processing method according to claim 9, wherein the encoder is set such that the encode of the audio stream subjected to the signal processing is performed by a codec of a type same as that of the codec used for the encode of the compressed audio stream.

11. A computer program for causing a computer to execute processing including:

decoding a compressed audio stream encoded by a predetermined codec;

applying predetermined signal processing to an audio stream obtained by decoding the compressed audio stream;

acquiring at least one of information described in a header of the compressed audio stream and management information for contents including the compressed audio stream;

discriminating, on the basis of the acquired information, a type of the codec used for the encode of the compressed audio stream and setting a codec used for encode of the audio stream subjected to the signal processing; and

encoding, in accordance with the setting, the audio stream subjected to the signal processing and outputting the audio stream to an external apparatus that has a decoder.

12. A computer program according to claim 11, wherein the encoder is set such that the encode of the audio stream subjected to the signal processing is performed by a codec of a type same as that of the codec used for the encode of the compressed audio stream.