Out of Phase Digital Watermarking in Two Chrominance Directions

A method comprising:

• obtaining first data representing a first chrominance channel of a color image or video signal, where the first data comprises a watermark signal embedded therein;
• obtaining second data representing a second chrominance channel of the color image or video signal, the second data comprising the watermark signal embedded therein but with a signal polarity that is inversely related to the polarity of the watermark signal in the first data;
• combining the second data with the first data in a manner that reduces image or video interference relative to the watermark signal, said act of combining yielding third data;
• using at least a processor or electronic processing circuitry, processing the third data to obtain the watermark signal;
• once obtained, providing information associated with the watermark signal.

An apparatus comprising:

• a processor or electronic processing circuitry to control:
• (a) handling of first data representing a first color channel of a color image or video signal, where the first data comprises a watermark signal embedded therein;
• (b) handling of second data representing a second color channel of the color image or video signal, the second data comprising the watermark signal embedded therein but with a signal polarity that is inversely related to the polarity of the watermark signal in the first data;
• (c) combining the second data with the first data in manner that reduces image or video signal interference relative to the watermark signal, the combining yielding third data;
• (d) processing the third data to obtain the watermark signal;
• (e) once obtained, providing information associated with the watermark signal.

A method comprising:

• obtaining first data representing a first chrominance channel of a color image or video signal;
• obtaining second data representing a second chrominance channel of the color image or video signal;
• using a processor or electronic processing circuitry, embedding a watermark signal in the first data with a first signal polarity;
• using a processor or electronic processing circuitry, transforming the second data by embedding the watermark signal in the second data so that when embedded in the second data the watermark signal comprises a second signal polarity that is inversely related to the first signal polarity of the watermark signal in the first data;
• combining the watermarked first data and the watermarked second data to yield a watermarked version of the color image or video signal,
• whereby during detection of the watermark signal from the watermarked version of the color image or video signal, the second data is combined with the first data in a manner that reduces image or video signal interference relative to the watermark signal.