Vector quantizer and vector quantization method

• US 6,278,385 B1
• Filed: 01/31/2000
• Issued: 08/21/2001
• Est. Priority Date: 02/01/1999
• Status: Expired due to Fees

• Current Assignee: Yamaha Corporation
• Original Assignee: Yamaha Corporation
• Inventors: Yamauchi, Kenichi, Kobayashi, Eiko, Kondo, Kazunobu
• Primary Examiner(s): JeanPierre, Peguy
• Assistant Examiner(s): Jeanglaude, Jean Bruner
• Application Number:
  US09/495,411
• Time in Patent Office: 568 Days
• Field of Search: 341/50, 341/51, 341/60, 341/200, 704/200, 704/205, 704/207, 704/214, 704/220
• US Class Current: 341/50
• CPC Class Codes: G06T 9/008 Vector quantisation
• CPC Class Codes: H04N 19/126 Details of normalisation or weighting functions, e.g. normalisation matrices or variable uniform quantisers
• CPC Class Codes: H04N 19/60 using transform coding
• CPC Class Codes: H04N 21/23892 involving embedding information at multiplex stream level, e.g. embedding a watermark at packet level
• CPC Class Codes: H04N 21/8358 involving watermark protecting executable software by watermarking G06F21/16; image watermarking in general G06T1/0021; watermarks inserted in still images for transmission purposes H04N1/32144; inserting watermarks during video coding H04N19/467

Abstract

A vector quantizer and a vector quantization method are provided, which do not allow the embedding position of the watermark information to be identified easily, and thus enable unfair use of the vector quantized information to be accurately found out. Waveform extraction is performed on input signal data to output extracted waveform data. Index data are generated based on the output extracted waveform data. As index data to be generated based on predetermined extracted waveform data in which no watermark information is to be embedded, out of the output extracted waveform data, index data is randomly selected, which corresponds to the predetermined extracted waveform data from a plurality of index data which, when decoded, have amounts of errors falling within a predetermined range with respect to the predetermined extracted waveform data before decoding.

Claims

1. A vector quantizer for performing vector quantization on input signal data, comprising:

a waveform extracting device that performs waveform extraction on said input signal data to output extracted waveform data; and

an index generating device that generates index data based on the output extracted waveform data;

wherein as index data to be generated based on predetermined extracted waveform data in which no watermark information is to be embedded, out of the output extracted waveform data, said index generating device randomly selects index data corresponding to the predetermined extracted waveform data from a plurality of index data which, when decoded, have amounts of errors falling within a predetermined range with respect to the predetermined extracted waveform data before decoding.

3. A vector quantizer as claimed in claim 1, comprising a first vector quantizing device to an n-th vector quantizing device (n is an integer not less than 2) for performing multistage vector quantization.

4. A vector quantizer as claimed in claim 3, wherein at least one of said first vector quantizing device to said n-th vector quantizing device includes a dummy data adding device for adding dummy data to a portion of said extracted waveform data when generating said extracted waveform data.

5. A vector quantizer as claimed in claim 1, further comprising a dummy data adding device that adds dummy data to a portion of said extracted waveform data when generating said extracted waveform data.

6. A vector quantizer as claimed in claim 5, wherein said extracted waveform data is formed of a predetermined finite number of sample data, and wherein said dummy data adding device divides said input signal data into a plurality of divided data each formed of a predetermined number of sample data smaller than said predetermined finite number of sample data, said dummy data adding device adding said dummy data to each of said plurality of divided data to thereby generate said extracted waveform data formed of said predetermined finite number of sample data.

7. A vector quantizer as claimed in claim 6, wherein a number of said sample data of said dummy data is different between when said divided data has watermark information embedded therein and when said divided data has no watermark information embedded therein.

8. A vector quantizer as claimed in claim 6, wherein said dummy data adding device repeatedly adds said dummy data formed of a predetermined fixed number of sample data to said divided data until said divided data becomes formed of sample data equal in number to said predetermined finite number.

9. A vector quantizer as claimed in claim 6, wherein said dummy data adding device adds, as said dummy data, calculated data obtained by performing a predetermined operation based on said divided data and formed of a number of sample data being equal to a difference between a number of sample data of said extracted waveform data and a number of sample data of said divided data.

10. A vector quantizer as claimed in claim 9, wherein said calculated data is calculated by extrapolation operation.

11. A vector quantizer as claimed in claim 9, wherein said operation data is calculated by interpolation operation.

2. A vector quantizer for performing conjugate structure vector quantization on input signal data, comprising:

a waveform extracting device that performs waveform extraction on said input signal data to output extracted waveform data; and

an index generating device that generates index data based on the output extracted waveform data;

wherein as a combination of index data to be generated based on predetermined extracted waveform data in which no watermark information is to be embedded, out of the output extracted waveform data, said index generating device randomly selects a combination of index data corresponding to the predetermined extracted waveform data from a plurality of combinations of index data which, when decoded, have amounts of errors falling within a predetermined range with respect to the predetermined extracted waveform data before decoding.

12. A vector quantization method for performing vector quantization on input signal data, comprising the steps of:

performing waveform extraction on said input signal data to output extracted waveform data; and

generating index data based on the output extracted waveform data;

wherein as index data to be generated based on predetermined extracted waveform data in which no watermark information is to be embedded, out of the output extracted waveform data, said index generating step randomly selects index data corresponding to the predetermined extracted waveform data from a plurality of index data which, when decoded, have amounts of errors falling within a predetermined range with respect to the predetermined extracted waveform data before decoding.

13. A vector quantization method as claimed in claim 12, further comprising the step of adding dummy data to a portion of said extracted waveform data when generating said extracted waveform data.

14. A vector quantization method for performing conjugate structure vector quantization on input signal data, comprising, comprising the steps of:

performing waveform extraction on said input signal data to output extracted waveform data; and

generating index data based on the output extracted waveform data;

wherein as a combination of index data to be generated based on predetermined extracted waveform data in which no watermark information is to be embedded, out of the output extracted waveform data, said index generating step randomly selects a combination of index data corresponding to the predetermined extracted waveform data from a plurality of combinations of index data which, when decoded, have amounts of errors falling within a predetermined range with respect to the predetermined extracted waveform data before decoding.

15. A vector quantizer for performing vector quantization on input signal data, comprising:

a time axis/frequency axis conversion and waveform extraction device that performs time axis/frequency axis conversion and waveform extraction on said input signal data to output frequency axis extracted waveform data; and

an index generating device that performs vector quantization on the output frequency axis extracted waveform data to generate index data;

wherein said index generating device adds watermark information data to at least one of a plurality of said frequency axis extracted waveform data corresponding to at least one frequency band component higher than a predetermined frequency.

16. A vector quantizer as claimed in claim 15, wherein said index generating device comprises a plurality of code books storing said index data in advance, and a plurality of encoding devices that assign said index data stored in respective corresponding ones of said code books to said frequency axis extracted waveform data, and wherein as index data to be assigned to said frequency axis extracted waveform data, one of said plurality of encoding devices corresponding to one frequency band component higher than said predetermined frequency randomly selects index data from a plurality of index data which, when decoded, have amounts of errors falling within a predetermined range with respect to the extracted waveform data before decoding, from among said index data stored in one of said code books corresponding to said one encoding device.

17. A vector quantizer as claimed in claim 15, wherein said index generating device comprises a plurality of code books storing said index data in advance, and a plurality of encoding devices that assign said index data stored in respective corresponding ones of said code books to said frequency axis extracted waveform data, and wherein in a case that there are a plurality of said encoding devices corresponding to frequency band components higher than said predetermined frequency, as index data to be assigned to said frequency axis extracted waveform data, at least one encoding device which is randomly selected from said plurality of encoding devices randomly selects index data from a plurality of index data which, when decoded, have amounts of errors falling within a predetermined range with respect to the extracted waveform data before decoding, from among said index data stored in at least one of said code books corresponding to said at least one encoding device.

18. A vector quantizer as claimed in claim 15, wherein said input signal data is audio data, said predetermined frequency being set based on human auditory sensation to a frequency at or above which little influence of watermark information can be exerted upon human auditory sensation.

19. A vector quantizer for performing vector quantization on input signal data, comprising:

a time axis/frequency axis conversion and waveform extraction device that performs time axis/frequency axis conversion and waveform extraction on said input signal data to output frequency axis extracted waveform data; and

a watermark information adding device that adds watermark information data to at least one of a plurality of the output frequency axis extracted waveform data which contains in large amounts frequency band components higher than a predetermined frequency, among frequency band components contained in said plurality of the output frequency axis extracted waveform data.

20. A vector quantizer as claimed in claim 19, further comprising:

a time axis/frequency axis conversion device that performs time axis/frequency axis conversion on said input signal data to output frequency axis input signal data; and

an interleave and waveform extraction device that interleave said frequency axis input signal data to generate interleaved frequency axis input signal data, and performs waveform extraction on said interleaved frequency axis input signal data to output frequency axis extracted waveform data.

21. A vector quantizer as claimed in claim 20, further comprising a watermark information adding device that adds watermark information data to at least one of a plurality of the output frequency axis extracted waveform data which contains in large amounts frequency band components higher than a predetermined frequency, among frequency band components contained in said plurality of the output frequency axis extracted waveform data.

22. A vector quantization method for performing vector quantization on input signal data, comprising the steps of:

performing time axis/frequency axis conversion and waveform extraction on said input signal data to output frequency axis extracted waveform data; and

performing vector quantization on the output frequency axis extracted waveform data to generate index data;

wherein said index generating step adds watermark information data to at least one of a plurality of said frequency axis extracted waveform data corresponding to at least one frequency band component higher than a predetermined frequency.

23. A vector quantization method for performing vector quantization on input signal data, comprising the steps of:

performing time axis/frequency axis conversion and waveform extraction on said input signal data to output frequency axis extracted waveform data; and

adding watermark information data to at least one of a plurality of the output frequency axis extracted waveform data which contains in large amounts frequency band components higher than a predetermined frequency, among frequency band components contained in said plurality of the output frequency axis extracted waveform data.