Steganography in Digital Signal Encoders

• US 20110131047A1
• Filed: 08/29/2007
• Published: 06/02/2011
• Est. Priority Date: 09/15/2006
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: RWTH Aachen University
• Inventors: Geiser, Bernd, Vary, Peter
• Granted Patent: US 8,412,519 B2
• Time in Patent Office: Days
• US Class Current: 704/270
• CPC Class Codes: G10L 19/018 Audio watermarking, i.e. embedding inaudible data in the audio signal
• CPC Class Codes: G10L 19/12 the excitation function being a code excitation, e.g. in code excited linear prediction [CELP] vocoders
• CPC Class Codes: G10L 2019/0007 Codebook element generation
• CPC Class Codes: H04K 1/00 Secret communication

Abstract

In a method for embedding steganographic information into the signal information of a signal encoder, a solution is to be created, which enables steganographic information being embedded into the signal information of a signal encoder such that a reduction of the voice quality is largely avoided. This is achieved by means of providing data information, particularly voice information, selecting steganographic information from a quantity of steganographic information, generating a code word from a code book provided by means of the signal encoder on the basis of the code elements forming the code book such that with the use of the code word generated within the scope of a transmission standard associated with the code book the data information is encoded into signal information containing the code word and/or making reference to the code word; and by the code word generated having an additional feature that can be calculated on the basis of the code elements forming the code word, wherein the additional feature represents the steganographic information.

Claims

1-13. -13. (canceled)

14. A method for embedding steganographic information into signal information of a signal encoder, comprising:

providing data information;

selecting steganographic information from a set of steganographic information items; and

generating a code word from a provided code book using the signal encoder as a function of code elements forming the code word so that (a) the data information is encoded, by using the generated code word within the scope of a transmission standard which is associated with the code book, into signal information containing the code word and/or pointing to the code word; and

(b) the generated code word has an additional characteristic which is calculated as a function of the code elements forming the code word, the additional characteristic representing the steganographic information.

15. The method of claim 14, wherein the data information includes voice information.

16. The method of claim 14, wherein an evaluation of the generated code word within the scope of a transmission standard which is associated with the code book provided, by decoding the code word and subsequently comparing the decoded data information with the original data information.

17. The method of claim 15, wherein generating the code word from the provided code book using the signal encoder as a function of the code elements forming the code word, taking into consideration the evaluation.

18. The method of claim 14, wherein use of an encoder and code book based on at least one of the GSM transmission standard and the UMTS transmission standard.

19. The method of claim 14, wherein generating a code word as a function of one of the CELP coding, the ACELP coding and the AMR coding.

20. The method of claim 14, wherein calculating the characteristic of the code word as the result of an application of at least one operation on at least one of the code elements forming the code word.

21. The method of claim 14, wherein providing the code word so that the code word implicitly fulfills the characteristic.

22. The method of claim 14, wherein selecting the steganographic information so that the steganographic information is used for improving the signal on the receiver side.

23. The method of claim 14, wherein selecting the steganographic information so that the steganographic information is used for at least one of an artificial bandwidth extension and a noise reduction on the receiver side.

24. The method of claim 14, wherein selecting the steganographic information so that the steganographic information is used as a digital watermark.

25. The method of claim 14, wherein transmitting the signal information one of containing the code word and pointing to the code word to a receiver.

26. The method as claimed in claim 25, wherein providing data information on the receiver side by decoding the code word within the scope of a transmission standard which is associated with the code book provided.

27. The method of claim 25, wherein providing the steganographic information on the receiver side by calculating the additional characteristic of the code word as a function of the code elements forming the code word.

28. The method of claim 14, wherein the method is utilized in a mobile radio device.