Apparatus for processing framed audio data for fade-in/fade-out effects

• US 20050234714A1
• Filed: 03/08/2005
• Published: 10/20/2005
• Est. Priority Date: 04/05/2004
• Status: Active Grant

• Current Assignee: KDDI Corporation
• Original Assignee: KDDI Corporation
• Inventors: Takagi, Koichi, Sakazawa, Shigeyuki
• Granted Patent: US 7,472,069 B2
• Time in Patent Office: Days
• US Class Current: 704/225
• CPC Class Codes: G10L 19/083 the excitation function being an excitation gain G10L25/90 takes precedence
• 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: G10L 21/0364 for improving intelligibility

Abstract

The present invention relates to an apparatus that process framed audio data to add fade-in and/or fade-out effect with low computing speed and small memory. According to the invention, the apparatus includes deframer (10) for taking an original value of a first gain parameter from an input audio frame, first gain parameter adjuster (12) for adjusting the first gain parameter based on the original value for preset duration, and framer (14) for generating an output audio frame, which has the adjusted value for the first gain parameter.

Claims

1. An apparatus for processing framed audio data for fade-in and/or fade-out effects, comprising:

deframe means for taking an original value of a first gain parameter from an input audio frame;

first gain parameter adjustment means for adjusting the first gain parameter based on the original value for preset duration; and

frame means for generating an output audio frame, the output audio frame having the adjusted value for the first gain parameter.

2. The apparatus of claim 1, wherein said input audio frame has audio data encoded by Advanced Audio Coding, and wherein said first gain parameter is a global-gain.

3. The apparatus of claim 2, wherein said deframe means further takes a scale factor from said input audio frame,

wherein the apparatus further comprises means for determining the minimum value of quantization step based on the scale factor and said original value of global-gain, and

wherein said first gain parameter adjustment means calculates the minimum value for the global-gain by subtracting the minimum value of quantization step from said original value of global-gain, and keeps the global-gain above the minimum value for the global-gain.

4. The apparatus of claim 1, wherein said deframe means further takes values in a second gain parameter from said input audio frame,

wherein the apparatus further comprises second gain parameter adjustment means for adjusting the second gain parameter for preset duration, and

wherein said frame means generates said output audio frame further having the adjusted values for the second gain parameter.

5. The apparatus of claim 4, wherein said input audio frame has audio data encoded by both Advanced Audio Coding and Spectral Band Replication, and

wherein said first gain parameter is a global-gain and said second gain parameter is a bs_data_env.

6. The apparatus of claim 1, wherein said first gain parameter adjustment means changes the first gain parameter based on a preset function of time.

7. A computer program product for processing framed audio data for fade-in and/or fade-out effects, comprising:

first instruction means for taking an original value of a first gain parameter from an input audio frame;

second instruction means for adjusting the first gain parameter based on the original value for preset duration; and

third instruction means for generating an output audio frame, the output audio frame having the adjusted value for the first gain parameter.

8. The computer program product of claim 7, wherein said input audio frame has audio data encoded by Advanced Audio Coding, and wherein said first gain parameter is a global-gain.

9. The computer program product of claim 8, wherein said first instruction means further takes a scale factor from said input audio frame,

wherein the apparatus further comprises fourth instruction means for determining the minimum value of quantization step based on the scale factor and said original value of global-gain, and

wherein said second instruction means calculates the minimum value for the global-gain by subtracting the minimum value of quantization step from said original value of global-gain, and keeps the global-gain above the minimum value for the global-gain.

10. The computer program product of claim 7, wherein said first instruction means further takes values in a second gain parameter from said input audio frame,

wherein the apparatus further comprises fifth instruction means for adjusting the second gain parameter for preset duration, and

wherein said third instruction means generates said output audio frame further having the adjusted values for the second gain parameter.

11. The computer program product of claim 10, wherein said input audio frame has audio data encoded by both Advanced Audio Coding and Spectral Band Replication, wherein said first gain parameter is a global-gain and said second gain parameter is a bs_data_env.

12. The computer program product of claim 7, wherein said second instruction means changes the first gain parameter based on a preset function of time.