Dynamic wavelet feature-based watermark
A dynamic wavelet feature-based watermark for use with digital video. Scene change detection separates digital data into one or more scenes, wherein each of the scenes is comprised of one or more frames. A temporal wavelet transformation decomposes the frames of each scene into dynamic frames and static frames. The static frames of each scene are subjected to a spatial wavelet transformation, so that the watermark can be cast into middle frequency sub-bands resulting therefrom. Polyphase-based feature selection or local block-based feature selection is used to select one or more features. The watermark is cast into the selected features by means of either (1) a comparison of energy in polyphase transform components of the selected feature, or (2) a change in value of blocked wavelet coefficients of the selected feature.
1. A method of casting a watermark in digital data, comprising:
(a) performing scene change detection to separate the digital data into one or more scenes, wherein each of the scenes is comprised of one or more frames;
(b) performing a temporal wavelet transformation that decomposes the frames of each scene into dynamic frames and static frames;
(c) performing a spatial wavelet transformation only on the static frames of each scene to generate a plurality of spatial sub-bands of the static frames;
(d) selecting one or more features in one or more selected ones of the generated spatial sub-bands of the static frames; and
(e) casting the watermark into the selected features.
2. The method of claim 1 , further comprising extracting a Y component of a Y, U(Cb), V(Cr) digital data stream representing color components of digital video as the digital data for the scene change detection.
3. The method of claim 1 , wherein the watermark is embedded in one or more middle frequency sub-bands resulting from the spatial wavelet transformation.
4. The method of claim 1 , wherein the features are selected using a polyphase-based feature selection.
5. The method of claim 4 , wherein the watermark is cast into the selected features by means of a comparison of energy in polyphase transform components of the selected feature.
6. The method of claim 1 , wherein the features are selected using a local block-based feature selection.
7. The method of claim 6 , wherein the watermark is cast into the selected features by means of a change in value of blocked wavelet coefficients of the selected feature.
8. The method of claim 1 , wherein the watermark is cast across all frames in each scene.
9. The method of claim 1 , further comprising performing a spatial wavelet reconstruction to reconstruct the static frames with the cast watermark of each scene.
10. The method of claim 9 , wherein the spatial wavelet reconstruction comprises a spatial inverse-wavelet transformation.
11. The method of claim 9 , further comprising performing a temporal wavelet reconstruction to recombine the dynamic frames with the static frames with the cast watermark to recreate each scene.
12. The method of claim 11 , wherein the temporal wavelet reconstruction comprises a temporal inverse-wavelet transformation.
13. The method of claim 11 , further comprising concatenating the recreated scenes and reinserting a Y component resulting therefrom into a Y, U(Cb), V(Cr) digital data stream representing the color components of the digital video.
14. An apparatus for casting a watermark in digital data, comprising:
(a) means for performing scene change detection to separate the digital data into one or more scenes, wherein each of the scenes is comprised of one or more frames;
(b) means for performing a temporal wavelet transformation that decomposes the frames of each scene into dynamic frames and static frames;
(c) means for performing a spatial wavelet transformation only on the static frames of each scene to generate a plurality of spatial sub-bands of the static frames;
(d) means for selecting one or more features in one or more selected ones of the generated spatial sub-bands of the static frames; and
(e) means for casting the watermark into the selected features.
15. The apparatus of claim 14 , further comprising means for extracting a Y component of a Y, U(Cb), V(Cr) digital data stream representing color components of digital video as the digits data for the scene change detection.
16. The apparatus of claim 14 , wherein the watermark is embedded in one or more middle frequency sub-bands resulting from the spatial wavelet transformation.
17. The apparatus of claim 14 , wherein the features are selected using a polyphase-based feature selection.
18. The appararus of claim 17 , wherein the watermark is cast into the selected features by means of a comparison of energy in polyphase transform components of the selected feature.
19. The apparatus of claim 14 , wherein the features are selected using a local block-based feature selection.
20. The apparatus of claim 19 , wherein the watermark is cast into the selected features by means of a change in value of blocked wavelet coefficients of the selected feature.
21. The apparatus of claim 14 , wherein the watermark is cast across all frames in each scene.
22. The apparatus of claim 14 , further comprising means for performing a spatial wavelet reconstruction to reconstruct the static frames with the cast watermark of each scene.
23. The apparatus of claim 22 , wherein the spatial wavelet reconstruction comprises a spatial inverse-wavelet transformation.
24. The apparatus of claim 22 , further comprising means for performing a temporal wavelet reconstruction to recombine the dynamic frames with the static frames with the cast watermark to recreate each scene.
25. The apparatus of claim 24 , wherein the temporal wavelet reconstruction comprises a temporal inverse-wavelet transformation.
26. The apparatus of claim 24 , further comprising means for concatenating the recreated scenes and for reinserting a Y component resulting therefrom into a Y, U(Cb), V(Cr) digital data stream representing the color components of the digital video.
27. A method of detecting a watermark in digital data, comprising:
(a) performing scene change detection to separate the digital data into one or more scenes, wherein each of the scenes is comprised of one or more frames;
(b) performing a temporal wavelet transformation that decomposes the frames of the scene into dynamic frames and static frames;
(c) performing a spatial wavelet transformation only on the static frames to generate a plurality of spatial sub-bands of the static frames;
(d) selecting one or more features in one or more selected ones of the generated spatial sub-bands of the static frames; and
(e) detecting the watermark in the selected features.
28. The method of claim 27 , further comprising extracting a Y component of a Y, U(Cb), V(Cr) digital data stream representing color components of digital video as the digital data for the scene change detection.
29. The method of claim 27 , wherein the watermark is embedded in one or more middle frequency sub-bands resulting from the spatial wavelet transformation.
30. The method of claim 27 , wherein the features are selected using a polyphase-based feature selection.
31. The method of claim 30 , wherein the watermark is detected from the selected features by means of a comparison of energy in polyphase transform components of the selected feature.
32. The method of claim 27 , wherein the features are selected using a local block-based feature selection.
33. The method of claim 32 , wherein the watermark is detected from the selected features by means of a change in value of blocked wavelet coefficients of the selected feature.
34. The method of claim 27 , wherein the watermark is cast across all frames in a scene.
35. The method of claim 27 , further comprising iteratively performing steps (a)-(e) until all bits of the watermark in the static frames have been detected.
36. An apparatus for detecting a watermark in digital data, comprising:
(a) means for performing scene change detection to separate the digital data into one or more scenes, wherein each of the scenes is comprised of one or more frames;
(b) means for performing a temporal wavelet transformation that decomposes the frames of the scene into dynamic frames and static frames;
(c) means for performing a spatial wavelet transformation only on the static frames to generate a plurality of spatial sub-bands of the static frames;
(d) means for selecting one or more features in one or more selected ones of the generated spatial sub-bands of the static frames; and
(e) means for detecting the watermark in the selected features.
37. The apparatus of claim 36 , further means for comprising extracting a Y component of a Y, U(Cb), V(Cr) digital data stream representing color components of digital video as the digital data for the scene change detection.
38. The apparatus of claim 36 , wherein the watermark is embedded in one or more middle frequency sub-bands resulting from the spatial wavelet transformation.
39. The apparatus of claim 36 , wherein the features are selected using a polyphase-based feature selection.
40. The apparatus of claim 36 , wherein the watermark is detected from the selected features by means of a comparison of energy in polyphase transform components of the selected feature.
41. The apparatus of claim 36 , wherein the features are selected using a local block-based feature selection.
42. The apparatus of claim 41 , wherein the watermark is detected from the selected features by means of a change in value of blocked wavelet coefficients of the selected feature.
43. The apparatus of claim 36 , wherein the watermark is cast across all frames in a scene.
44. The apparatus of claim 36 , further comprising means for iteratively performing the means (a)-(e) until all bits of the watermark in the static frames have been detected.