Reducing watermark perceptibility and extending detection distortion tolerances
The present disclosures relates generally to digital watermarking and data hiding. One claim recites an apparatus comprising: means for storing a watermark signal; means for embedding a watermark signal in a first portion of a video signal; means for preconditioning the watermark signal in a first manner to allow expanded detection of said preconditioned watermark signal in the presence of first distortion; means for embedding the watermark signal preconditioned in the first manner in a second portion of the video signal; means for preconditioning the watermark signal in a second manner to allow expanded detection of said preconditioned watermark signal in the presence of second distortion; and means for embedding the watermark signal preconditioned in the second manner in a third portion of the video signal. Of course, other claims are provided too.
1. An apparatus comprising:
means for storing data representing video;
means for embedding a first watermark signal in a first portion of stored data, the first watermark signal comprising a first signal polarity and corresponding to first detection preconditioning;
means for embedding a second watermark signal in a second portion of the stored data, the second watermark signal comprising a second signal polarity that is inversely related to the first signal polarity and corresponding to second detection preconditioning;
means for controlling provision of the watermarked video for display in real time, in which temporal averaging of the first watermark signal and second watermark signal over time conceals the first watermark signal and the second watermark signal from a human observer of the video.
2. The apparatus of claim 1 in which the first watermark signal and the second watermark signal are embedded in corresponding spatial positions of the video.
3. A mobile device comprising the apparatus of claim 1 .
4. An apparatus comprising:
means for storing data representing video;
means for embedding a watermark signal in a first portion of stored data, the embedding using a first embedding bump size;
means for embedding a watermark signal in a second portion of the stored data, the embedding using a second embedding bump size, in which the first embedding bump size corresponds with a first detection range distance when capturing optical scan data associated with the video as it is being rendered on a display, and the second embedding bump size corresponds with a second, larger detection range distance when capturing optical scan data associated with the video as it is being rendered on the display;
means for controlling provision of the watermarked video to a display.
5. The apparatus of claim 4 in which use of both the first embedding bump size and the second embedding bump size extends the detection range distance when capturing optical scan data associated with the rendered video.
6. The apparatus of claim 4 in which the optical scan data comprises video data captured from a means for displaying that is rendering the video.
7. The apparatus of claim 4 in which the first portion of the data comprises two or more video frames.
8. The apparatus of claim 7 in which the second portion of the data comprises two or more video frames.
9. A mobile device comprising the apparatus of claim 4 .
10. An apparatus comprising:
means for storing a watermark signal;
means for embedding a watermark signal in a first portion of a video signal;
means for preconditioning the watermark signal in a first manner to allow expanded detection of said preconditioned watermark signal in the presence of first distortion;
means for embedding the watermark signal preconditioned in the first manner in a second portion of the video signal;
means for preconditioning the watermark signal in a second manner to allow expanded detection of said preconditioned watermark signal in the presence of second distortion;
means for embedding the watermark signal preconditioned in the second manner in a third portion of the video signal.
11. The apparatus of claim 10 in which the first distortion is due to positive image capture perspective angle variance.
12. The apparatus of claim 11 in which the second distortion is due to negative image capture perspective angle variance.
13. The apparatus of claim 12 in which image capture perspective angle variance is introduced by a mobile device capturing imagery of a display that is rendering the watermarked video signal.
14. The apparatus of claim 11 in which image capture perspective angle variance is introduced by a mobile device capturing imagery of a means for displaying that is rendering the watermarked video signal.
15. The apparatus of claim 10 in which embedding the watermark signal preconditioned in the first manner in a second portion of the video signal uses a first embedding bump size; and in which embedding the watermark signal preconditioned in the second manner in a third portion of the video signal uses a second embedding bump size; and in which the first embedding bump size corresponds with a first optimal detection range distance when capturing optical scan data associated with the video signal as it is being rendered on a display, and the second embedding bump size corresponds with a second, larger optimal detection range distance when capturing optical scan data associated with the video signal as it is being rendered on the display.
16. A mobile device comprising the apparatus of claim 10 .