Audio encoding to convey auxiliary information, and media embodying same
AssigneeDigimarc Corporation
InventorGeoffrey B. Rhoads
Life of this patent
Estimating the term…
Abstract
Methods of processing audio to convey auxiliary information hidden therein are provided. Various arrangements are disclosed. One alters data representing audio to include a sequence of bits of auxiliary information. The altering is based on a carrier signal and corresponding to the sequence of bits, and is based on a perceptibility threshold that varies within the data representing audio. Other arrangements are provided as well.
Claims20
A method of embedding data in an audio signal, comprising:
- providing a message comprising message bits;
- associating carrier signals with the message bits;
- modulating the carrier signals according to values of the associated message bits, wherein the modulating changes a property of the carrier signal to correspond with a desired value of the associated message bit;
- adjusting the modulated carrier signals as a function of a perceptibility threshold computed from the audio signal where the carrier signals are to be embedded;
- and
- combining the adjusted carrier signals with the audio signal.
The method of claim h wherein the carrier signals comprise noise sequences.
A method of detecting data embedded in an audio signal, the method comprising:
- applying a carrier signal to the audio signal to produce an output signal including peaks corresponding to embedding locations of the carrier signal, wherein the peaks comprise positive and negative peaks;
- analyzing, using a processor, the output signal to perform a registration of the embedding locations in the output signal;
- and
- determining message values from the peaks at the embedding locations in the output signal.
An apparatus, comprising:
- one or more processors configured to:
- receive a message comprising message bits;
- associate carrier signals with the message bits;
- modulate the carrier signals according to values of the associated message bits, wherein the modulating changes a property of the carrier signal to correspond with a desired value of the associated message bit;
- adjust the modulated carrier signals as a function of a perceptibility threshold computed from the audio signal where the carrier signals are to be embedded;
- and
- combine the adjusted carrier signals with the audio signal.
Dependencies are inferred from the claim text.