Method for generating hashes from a compressed multimedia content

• US 20050259819A1
• Filed: 04/12/2003
• Published: 11/24/2005
• Est. Priority Date: 06/24/2002
• Status: Abandoned Application

• Current Assignee: Gracenote, Inc. (RR Donnelley & Sons Company)
• Original Assignee: Koninklijke Philips N.V.
• Inventors: Haitsma, Jaap Andre, Kalker, Antonius Adrianus Cornelis Maria, Oomen, Arnoldus Werner Johannes, Middeljans, Jakobus
• Application Number:
  US10/518,264
• Publication Number:
  US 20050259819A1
• Time in Patent Office: Days
• US Class Current: 380/200
• CPC Class Codes: G10L 25/48 specially adapted for particular use
• CPC Class Codes: H04N 1/32101 Display, printing, storage or transmission of additional information, e.g. ID code, date and time or title
• CPC Class Codes: H04N 19/467 characterised by the embedded information being invisible, e.g. watermarking
• CPC Class Codes: H04N 19/60 using transform coding
• CPC Class Codes: H04N 19/63 using sub-band based transform, e.g. wavelets
• CPC Class Codes: H04N 2201/3236 Details of authentication information generation

Abstract

Method and apparatus for generating a hash signal representative of a multimedia signal are described. The method includes receiving a bit-stream comprising a compressed multimedia signal, selectively reading from the bit-stream predetermined parameters, and deriving a hash function from the parameters.

Claims

1. A method of generating a hash signal representative of a multimedia signal, the method comprising the steps of:

receiving a bit-stream comprising a compressed multimedia signal;

selectively reading from the bit-stream predetermined parameters; and

deriving a hash function from said parameters.

2. A method as claimed in claim 1, wherein said predetermined parameters relate to perceptual information of the multimedia signal.

3. A method as claimed in claim 1, wherein the multimedia signal comprises at least one of an audio signal, a video signal and an image signal.

4. A method as claimed in claim 1, wherein the multimedia signal has been compressed using at least one of transform encoding, subband encoding and parametric encoding.

5. A method as claimed in claim 1, wherein said predetermined parameters relate to at least one of the energies of frequency bands;

the amplitudes of frequency bands;

the tonality of frequency bands;

the luminance of an area of a video signal; and

the chrominance of an area of a video signal.

6. A method as claimed in claim 1, wherein the method further comprises the step of analysing the received bit-stream in order to determine the decoding scheme used to compress the multimedia signal.

7. A method as claimed in claim 6, wherein said analysing step comprises comparing the properties of the bit-stream with a database containing properties of a number of coding schemes.

8. A method as claimed in claim 1, wherein said step of selectively reading predetermined parameters comprises:

locating said predetermined parameters within the bit-stream by using the syntax description;

reading the located predetermined parameters; and

decoding the predetermined parameter using the decoder description.

9. A method as claimed in claim 1, wherein said predetermined parameters relate to a first set of frequency bands, and wherein the step of deriving the hash function comprises deriving estimates of values of spectral information present in a second set of frequency bands from the predetermined parameters, the hash function subsequently being calculated from the estimated values.

10. A method as claimed in claim 1, wherein said multimedia signal is compressed using a parametric encoding scheme, and wherein the predetermined parameters relate to at least one of the sinusoidal components, the noise components and the transient components utilised within the parametric scheme.

11. A computer program arranged to perform the method as claimed in claim 1.

12. A record carrier comprising a computer program as claimed in claim 11.

13. A method of making available for downloading a computer program as claimed in claim 11.

14. A hash signal representative of a multimedia signal, the hash signal having been generated by selectively reading predetermined parameters relating to perceptual properties of the multimedia signal from a bit-stream comprising a compressed version of the multimedia signal.

15. An apparatus arranged to generate a hash signal representative of a multimedia signal, the apparatus comprising:

a receiver arranged to receive a bit-stream comprising a compressed multimedia signal;

a decoder (210) arranged to selectively read from the bit-stream predetermined parameters;

a processing unit (270) arranged to derive a hash function from said parameters.