Color selection scheme for digital video watermarking
First Claim
1. A method performed by an apparatus for watermarking a video signal, the method comprising the step of:
- automatically selecting a chrominance portion of a pixel of an image of a video signal to be watermarked, said video signal to be watermarked without changing its luminance, said selecting step employing a perception-based table that is independent of said image and indicates for each of at least a plurality of possible pixels in a colorspace which, if any, of the chrominance portions of said plurality of pixels in said colorspace should be selected for watermarking, said table being stored in a computer readable medium.
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0 Petitions
Accused Products
Abstract
Determining a chrominance portion to be watermarked employs a perception-based table that indicates for various pixel values which of the chrominance portions, if any, should be selected for watermarking. Only the Y, U, and V values of a pixel are needed to access the table and determine which chrominance portion should be selected. However, the table may be represented such that it may be accessed using only R, G, and B values. The table may be modified so that it may indicate which of U or V should be selected, or that neither should be selected, indicating that this pixel should not be watermarked at all. Advantageously, the table may be simplified by employing some processing, because a large section of the table may be replaced by a simple test on the pixel values, e.g., U<128, to determine the selected chrominance portion.
21 Citations
34 Claims
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1. A method performed by an apparatus for watermarking a video signal, the method comprising the step of:
automatically selecting a chrominance portion of a pixel of an image of a video signal to be watermarked, said video signal to be watermarked without changing its luminance, said selecting step employing a perception-based table that is independent of said image and indicates for each of at least a plurality of possible pixels in a colorspace which, if any, of the chrominance portions of said plurality of pixels in said colorspace should be selected for watermarking, said table being stored in a computer readable medium. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16)
- 17. Apparatus for supplying an indication as to which chrominance portion of a pixel an image of a video signal, if any, is better suited to be altered so as to carry additional watermark information without changing said pixel'"'"'s luminance, said apparatus comprising a perception-based table in a computer readable media for at least a portion of the possible pixel colorspace, said table being independent of said image, said table specifying for pixels that are within said portion of said colorspace the chrominance portion to be indicated by said apparatus.
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20. A method for that is performed by an apparatus for detecting watermark data that was added to a video signal, the method comprising the step of:
automatically selecting a chrominance portion of a pixel of an image of a video signal, said video signal having been watermarked without changing its luminance, said selecting step employing a perception-based table that is independent of said image and which indicates for each of at least a plurality of possible pixels in a colorspace which, if any, of the chrominance portions most likely had watermark data added thereto, said table being stored in a computer readable medium.
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21. Apparatus for selecting a chrominance portion of a pixel of an image of a video signal to be watermarked, said apparatus comprising a perception-based table in a computer readable medium that indicates for each of at least a plurality of possible pixels in at least a portion of a colorspace which if any, of the chrominance portions would be least likely to introduce a visible artifact should watermark data be added thereto, said video signal to be watermarked without changing its luminance.
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22. Apparatus for selecting a chrominance portion of a pixel of an image of a video signal to be watermarked so that there are effectively no changes to a luminance of said video signal, said apparatus comprising:
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a computer readable store containing a perception-based table that is independent of said image and which indicates for each of at least a plurality of possible pixels in at least a portion of a colorspace which, if any, of the chrominance portions should be selected for watermarking; and means for accessing said store to determine which chrominance portion, if any, to select, when said pixel of said image to be watermarked is one of said pixels in said portion of said colorspace. - View Dependent Claims (23)
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24. Apparatus for selecting a chrominance portion of a pixel of an image of a video signal, said video signal having been watermarked without changing its luminance, said apparatus comprising:
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a computer readable store containing a perception-based table that is independent of said image and which indicates for each of at least a plurality of possible pixels in at least a portion of a colorspace which, if any, of the chrominance portions most likely had watermarking data added thereto; and means for accessing said store to determine which chrominance portion, if any, to select, when said pixel is one of said pixels in said portion of said colorspace.
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25. Apparatus in a receiver for selecting a chrominance portion of a pixel of an image of a video signal that may have been watermarked in a transmitter, said video signal having been watermarked so as not to change its luminance, the apparatus comprising:
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a computer readable store containing a perception-based table that is independent of said image and which indicates for each of at least a plurality of possible pixels in at least a portion of a colorspace which, if any, of the chrominance portions was most likely selected to be watermarked; and means for accessing said store to determine which chrominance portion, if any, to select, when said pixel of said image is within said portion of said colorspace.
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26. A method performed by an apparatus for watermarking a video signal, the method comprising the step of:
automatically selecting at most one chrominance portion of a pixel of an image of a video signal to be watermarked by adding thereto additional information, said selecting step employing a perception-based table that is independent of (i) said image and (ii) said additional information, said table indicating for each of at least a plurality of possible pixels in a colorspace which one, if any, of the chrominance portions of said plurality of pixels in said colorspace should be selected to have said additional information added thereto, said table being stored in a computer readable medium.
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27. Apparatus for supplying an indication as to which chrominance portion of a pixel an image of a video signal, if any, is better suited to be altered so as to carry additional watermark information, said apparatus comprising a perception-based table in a computer readable media for at least a portion of the possible pixel colorspace, said table being independent of (i) said image and (ii) said additional watermark information, said table specifying for pixels that are within said portion of said colorspace the chrominance portion to be indicated by said apparatus.
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28. A method that is performed by an apparatus for detecting watermark information that was added to a video signal, the method comprising the step of:
automatically selecting a chrominance pardon of a pixel of an image of a video signal, said video signal having been watermarked with watermark information, said selecting step employing a perception-based table that is independent of (i) said image and (ii) said watermark information and which indicates for each of at least a plurality of possible pixels in a colorspace which, if any, of the chrominance portions most likely had watermark information added thereto, said table being stored in a computer readable medium.
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29. Apparatus for selecting a chrominance portion of a pixel of an image of a video signal to be watermarked by adding thereto additional information, said apparatus comprising a perception-based table in a computer readable medium that is independent of (i) said image and (ii) said additional information and which indicates for each of at least a plurality of possible pixels in at least a portion of a colorspace which, if any, of the chrominance portions would be least likely to introduce a visible artifact should watermark data be added thereto.
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30. A method that is performed by an apparatus for detecting watermark data that was added to a video signal, the method comprising the step of:
automatically selecting a chrominance portion of a pixel of an image of a video signal that had watermark data added thereto, said selecting step employing a perception-based table that is independent of (i) said image and (ii) said watermark data and which indicates for each of at least a plurality of possible pixels in a colorspace which, if any, of the chrominance portions most likely had watermark data added thereto, said table being stored in a computer readable medium.
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31. A method performed by an apparatus for watermarking a video signal, the method comprising the step of:
automatically selecting no more than one chrominance portion of a pixel of an image of a video signal to be watermarked, said selecting step employing a perception-based table that is independent of said image and indicates for each of at least a plurality of possible pixels in a colorspace which, if any, of the chrominance portions of said plurality of pixels in said colorspace should be selected for watermarking, said table being stored in a computer readable medium.
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32. Apparatus for supplying an indication as to only one of which, if any, chrominance portion of a pixel an image of a video signal, is better suited to be altered so as to carry additional watermark information, said apparatus comprising a perception-based table in a computer readable media for at least a portion of the possible pixel colorspace, said table being independent of said image, said table specifying for pixels that are within said portion of said colorspace the particular no more than one chrominance portion to be indicated by said apparatus.
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33. A method for that is performed by an apparatus for detecting watermark data that was added to a video signal, the method comprising the step of:
automatically selecting no more than one of a chrominance portion of a pixel of an image of a video signal, said video signal having been watermarked, said selecting step employing a perception-based table that is independent of said image and which indicates for each of at least a plurality of possible pixels in a colorspace which, if any, of the chrominance portions most likely had said watermark data added thereto, said table being stored in a computer readable medium.
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34. Apparatus for selecting no more than one chrominance portion of a pixel of an image of a video signal to be watermarked, said apparatus comprising a perception-based table in a computer readable medium that indicates for each of at least a plurality of possible pixels in at least a portion of a colorspace which, if any, of the chrominance portions would be least likely to introduce a visible artifact should watermark data be added thereto.
Specification