Method for Dynamically Adjusting Audio Decoding Process

• US 20110099020A1
• Filed: 01/04/2011
• Published: 04/28/2011
• Est. Priority Date: 05/18/2007
• Status: Active Grant

• Current Assignee: MediaTek, Inc.
• Original Assignee: MediaTek, Inc.
• Inventors: Kuo, Pei-Yun, Chuang, Chih-Chiang
• Granted Patent: US 8,127,302 B2
• Time in Patent Office: Days
• US Class Current: 704/500
• CPC Class Codes: G11B 2020/00014 the compressed signal being an audio signal
• CPC Class Codes: H04S 1/007 in which the audio signals are in digital form data reduction aspects thereof based on psychoacoustics G10L19/02

Abstract

A method for dynamically arranging DSP tasks. The method comprises receiving an audio bit stream, checking a remaining execution time as the DSP transforms the audio information into spectral information, simplifying the step of transforming the audio information when the DSP detects that the remaining execution time is shorter then a predetermined interval, and skipping one section of the audio information and decoding the remaining section when the execution time is less than a predetermined interval.

Claims

1. A method for dynamically arranging DSP a plurality of tasks, wherein each task is associated with an interrupt and a priority, comprising:

receiving first audio information;

executing a audio decoding task unless an interrupt having a priority higher than the priority of the audio decoding task interrupts the DSP;

determining computation capacity of the DSP;

segmenting the second audio information into two sections according to the determined computation capacity of the DSP, wherein the two sections are a remaining section and ignoring section;

analyzing the remaining section into spectral domain; and

synthesizing the analyzed section.

2. The method as claimed in claim 1, wherein determining the computation capacity of the DSP comprises triggering a counter when the DSP begins the audio decoding task, and a counter value associating with the counter represents the remaining execution time, wherein the counter value decreases with time.

3. The method as claimed in claim 2, wherein the first audio information is a bit-stream, and the audio decoding task further comprises:

extracting a plurality of samples from the bit-stream; and

Fourier-transforming the plurality of samples into a plurality of frequency sub-bands, and the ignored section is the higher frequency sub-bands.

4. The method as claimed in claim 3, wherein extracting a plurality of samples from the bit-stream comprises:

Huffman-decoding the first bit-stream; and

Stereo-processing the Huffman decoded bit-stream to generate the plurality of samples.

5. The method as claimed in claim 3, wherein Fourier-transforming the plurality of samples is inverse-modified-discrete-cosine-transforming (IMDCTing) the plurality of samples to generate a plurality of frequency sub-bands, wherein the step of segmenting the second audio information into two sections is segmenting the plurality of samples into two sections, the ignored section and the remaining section.

6. The method as claimed in claim 1, wherein the step of synthesizing is polyphase synthesis of the analyzed section.

7. The method as claimed in claim 4, wherein the number of the plurality of frequency sub-band is 32.

8. The method as claimed in claim 6, wherein the ignored section is sub-band 29 to sub-band 32.

9. The method as claimed in claim 5, wherein the ignored section is the even numbered of sub-bands instead of the higher frequency of sub-bands.

10. The method as claimed in claim 5, wherein the ignored section is odd numbered of sub-band instead of the higher frequency of sub-bands.

11. A method of decoding audio information, comprising:

receiving the audio information;

segmenting the audio information into two sections; and

ignoring one section of the audio information and decoding the remaining section if computation capacity of a DSP for decoding audio information is lower than a threshold.

12. The method as claimed in claim 11, wherein determining the computation capacity of the DSP comprises triggering a counter when the DSP starts the audio decoding task, and a counter value associated with the counter represents the remaining execution time, wherein the counter value decreases with time.

13. The method as claimed in claim 12, wherein the audio information is a bit-stream, and the method further comprises:

extracting a plurality of samples according to the bit-stream; and

Fourier-transforming the plurality of samples into a plurality of frequency sub-bands, and the ignored section are higher frequency sub-bands.

14. The method as claimed in claim 13, wherein extracting a plurality of samples from the bit-stream comprises:

Huffman-decoding the bit-stream; and

Stereo-processing the Huffman decoded bit-stream to generate a plurality of samples.

15. The method as claimed in claim 13, wherein Fourier-transforming the plurality of samples is inverse-modified-discrete-cosine-transforming of the plurality samples to generate a plurality of frequency sub-bands, wherein the step of segmenting the audio information into two sections is segmenting the plurality of samples into two sections, a ignored section and a remaining section.

16. The method as claimed in claim 14, wherein the number of the plurality of frequency sub-bands is 32.

17. The method as claimed in claim 16, wherein the ignored section is sub-band 29 to sub-bands 32.

18. The method as claimed in claim 15, wherein the ignoring section is the even-numbered of sub-bands instead of the higher frequency of sub-bands.

19. The method as claimed in claim 15, wherein the ignored section is the odd-numbered of sub-bands instead of the higher frequency of sub-bands.