METHOD AND APPARATUS FOR ENCODING/DECODING MEDIA SIGNAL

• US 20090063163A1
• Filed: 08/05/2008
• Published: 03/05/2009
• Est. Priority Date: 08/31/2007
• Status: Abandoned Application

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: OH, Jae-one, LEE, Nam-suk, JEONG, Jong-hoon, LEE, Geon-hyoung
• Application Number:
  US12/186,128
• Publication Number:
  US 20090063163A1
• Time in Patent Office: Days
• US Class Current: 704/500
• CPC Class Codes: G10L 19/09 Long term prediction, i.e. removing periodical redundancies, e.g. by using adaptive codebook or pitch predictor
• CPC Class Codes: G10L 19/093 using sinusoidal excitation models

Abstract

Provided are a method and apparatus for encoding/decoding a media signal. The method of encoding a media signal includes: when harmonics exist in a sinusoid of a previous frame section, predicting a harmonic frequency of a current frame section that is to be encoded by using a harmonic frequency of the previous frame section, and generating a residual signal by using a difference between the predicted frequency and an actual harmonic frequency of the current frame section.

Claims

1. A method of encoding a media signal comprising a plurality of frames, the method comprising:

if a harmonic is in a sinusoid of a previous frame section, predicting a harmonic frequency of a current frame section that is to be encoded, by using a harmonic frequency of the previous frame section; and

determining a difference between the predicted harmonic frequency of the current frame section and an actual harmonic frequency of the current frame section to generate a residual signal.

2. The method of claim 1, wherein the predicting of the harmonic frequency of the current frame section comprises:

calculating an amount of fundamental frequency change by using a fundamental frequency of a sinusoid of the current frame section and a fundamental frequency of the sinusoid of the previous frame section; and

predicting a frequency of an n-th harmonic of the current frame section by using a frequency of an n-th harmonic of the previous frame section and the amount of fundamental frequency change, where n is an integer equal to or greater than 2.

3. The method of claim 2, wherein the predicting of the frequency of the n-th harmonic of the current frame section comprises:

predicting the frequency of the n-th harmonic of the previous frame section by multiplying the fundamental frequency of the sinusoid of the previous frame section by n; and

determining a sinusoid which has a frequency in a range of the predicted frequency of the n-th harmonic of the previous frame section, in the sinusoid of the previous frame section as the n-th harmonic of the previous frame section, and extracting the determined n-th harmonic.

4. The method of claim 3, wherein the predicting of the frequency of the n-th harmonic of the current frame section further comprises predicting a value which is obtained by adding the amount of the fundamental frequency change multiplied by n and the frequency of the n-th harmonic of the previous frame section, as the frequency of the n-th harmonic of the current frame section.

5. The method of claim 2, further comprising

encoding the amount of the fundamental frequency change;

and

encoding the residual signal.

6. The method of claim 1, further comprising, if the sinusoid of the previous frame section does not include any harmonics, encoding an actual frequency of a sinusoid of the current frame section.

7. The method of claim 1, further comprising encoding a phase and an amplitude of the sinusoid of the current frame section.

8. A method of decoding a media signal, comprising a plurality of frames, the method comprising:

if a harmonic is in a sinusoid of a previous frame section, predicting a harmonic frequency of a current frame section that is to be decoded, by using a harmonic frequency of the previous frame section; and

generating an actual harmonic frequency of the current frame section by using the predicted harmonic frequency.

9. The method of claim 8, wherein the generating of the actual harmonic frequency of the current frame section comprises:

determining a difference between the predicted frequency of the current frame section and an actual harmonic frequency of the current frame section, to extract a residual signal from the media signal; and

generating the harmonic frequency of the current frame section by using the predicted harmonic frequency and the residual signal.

10. The method of claim 8, wherein the predicting of the harmonic frequency of the current frame section comprises:

extracting an amount of fundamental frequency change which is a difference between a fundamental frequency of a sinusoid of the current frame section and a fundamental frequency of the sinusoid of the previous frame section, from the media signal; and

predicting a frequency of an n-th harmonic of the current frame section by using a frequency of an n-th harmonic of the previous frame section and the amount of fundamental frequency change, where n is an integer equal to or greater than 2.

11. The method of claim 10, wherein the predicting of the frequency of the n-th harmonic of the current frame section comprises:

predicting the frequency of the n-th harmonic of the previous frame section by multiplying the fundamental frequency of the sinusoid of the previous frame section by n; and

determining a sinusoid which has a harmonic frequency in a range of the predicted frequency of the n-th harmonic of the previous frame section, in the stored sinusoid of the previous frame section as the n-th harmonic of the previous frame section, and extracting the determined n-th harmonic.

12. The method of claim 10, wherein the predicting of the frequency of the n-th harmonic of the current frame section further comprises predicting a value which is obtained by adding the amount of the fundamental frequency change multiplied by n and the frequency of the n-th harmonic of the previous frame section, as the frequency of the n-th harmonic of the current frame section.

13. The method of claim 8, further comprising if the sinusoid of the previous frame section does not include any harmonics, decoding the actual frequency of a sinusoid of the current frame section.

14. The method of claim 8, further comprising decoding a phase and amplitude of a fundamental and the harmonics of the sinusoid of the current frame section.

15. An apparatus for encoding a media signal comprising a plurality of frames, the apparatus comprising:

a predictor which, if a harmonic is in a sinusoid of a previous frame section, predicts a harmonic frequency of a current frame section that is to be encoded, by using a harmonic frequency of the previous frame section; and

a second generator which generates a residual signal by using a difference between the predicted harmonic frequency of the current frame section and an actual harmonic frequency of the current frame section.

16. The apparatus of claim 15, further comprising a calculator which calculates an amount of fundamental frequency change by using a fundamental frequency of a sinusoid of the current frame section and a fundamental frequency of the sinusoid of the previous frame section,

wherein the predictor predicts a frequency of an n-th harmonic of the current frame section by using a frequency of an n-th harmonic of the previous frame section and the amount of fundamental frequency change, where n is an integer equal to or greater than 2.

17. The apparatus of claim 16, wherein the predictor predicts the frequency of the n-th harmonic of the previous frame section by multiplying the fundamental frequency of the sinusoid of the previous frame section by n, determines a sinusoid which has a frequency in a range of the predicted frequency of the n-th harmonic of the previous frame section, in the sinusoid of the previous frame section as the n-th harmonic of the previous frame section, and extracts the determined n-th harmonic.

18. The apparatus of claim 17, wherein the predictor predicts a value which is obtained by adding the amount of the fundamental frequency change multiplied by n and the frequency of the n-th harmonic of the previous frame section, as the frequency of the n-th harmonic of the current frame section.

19. The apparatus of claim 15, further comprising an encoder, which encodes the amount of the fundamental frequency change and the residual signal.

20. The apparatus of claim 19, wherein the encoder, the sinusoid of the previous frame section does not include any harmonics, encodes an actual frequency of a sinusoid of the current frame section.

21. An apparatus for decoding a media signal, comprising a plurality of frames, the apparatus comprising:

a predictor which, if a harmonic is in a sinusoid of a previous frame section, predicts a harmonic frequency of a current frame section that is to be decoded, by using a harmonic frequency of the previous frame section;

a first extractor which extracts a residual signal which is a difference between the predicted harmonic frequency of the current frame section and an actual harmonic frequency of the current frame section, from the media signal; and

a restorer which generates a harmonic frequency of the current frame section by using the predicted harmonic frequency of the current frame section and the residual signal.

22. The apparatus of claim 21, further comprising a second extractor which extracts an amount of fundamental frequency change, which is a difference between a fundamental frequency of a sinusoid of the current frame section and a fundamental frequency of the sinusoid of the previous frame section, from the media signal,

wherein the predictor predicts a frequency of an n-th harmonic of the current frame section by using a frequency of an n-th harmonic of the previous frame section and the amount of fundamental frequency change, where n is an integer equal to or greater than 2.

23. The apparatus of claim 22, wherein the predictor predicts a frequency of the n-th harmonic of the previous frame section by multiplying the fundamental frequency of the sinusoid of the previous frame section by n, determines a sinusoid which has a frequency in a range of the predicted frequency of the n-th harmonic of the previous frame section, in the sinusoid of the previous frame section as the n-th harmonic of the previous frame section, and extracting the determined n-th harmonic.

24. The apparatus of claim 22, wherein the predictor predicts a value which is obtained by adding the amount of the fundamental frequency change multiplied by n and the frequency of the n-th harmonic of the previous frame section, as the frequency of the n-th harmonic of the current frame section.