Varying segment sizes to increase security
First Claim
1. A watermarking system comprising:
- a watermark encoder that is configured to apply a watermark to each of a plurality of segments of content material to form a plurality of watermarked segments, anda size generator that is configured to control a size of the watermark that is applied to each of the plurality of segments, based on a random process, so that at least two watermarked segments of the plurality of watermarked segments have different watermark sizes in order for authorization of at least one of the plurality of watermarked segments be determined based on the watermark and based on the size of the watermark.
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Accused Products
Abstract
A security system is configured to use a variable length encoding of a security identifier for segments of protected content material. In this system, a distinction is made between a “zero” information bit, and the “absence” of the information bit in a shorter information item. A conventional N-bit information encoding is encoded as a variable bit encoding, wherein the information encoding ranges from N−k bits to N+k bits. By distinguishing “zero” bits from “absent” bits, this variable bit encoding allows for 2N−k+2N−(k−1) . . . +2N . . . +2N+(k−1)+2N+k possible unique information values. Preferably, the number of bits used for each encoding of a segment of a data set is a random value, further adding to the complexity of creating a dictionary mapping for protected content material.
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Citations
15 Claims
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1. A watermarking system comprising:
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a watermark encoder that is configured to apply a watermark to each of a plurality of segments of content material to form a plurality of watermarked segments, and a size generator that is configured to control a size of the watermark that is applied to each of the plurality of segments, based on a random process, so that at least two watermarked segments of the plurality of watermarked segments have different watermark sizes in order for authorization of at least one of the plurality of watermarked segments be determined based on the watermark and based on the size of the watermark. - View Dependent Claims (2, 3, 4, 5, 6, 7)
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8. An encoding system comprising:
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a segmenter that is configured to segment content material into a plurality of segments, and a size generator, operably coupled to the segmenter, that is configured to control a size of each of the plurality of segments, based on a random process, so that at least two segments of the plurality of segments have different sizes in order for authorization of at least one of the plurality of segments be determined based on the content material of said at least one of the plurality of segments and based on the size of said at least one of the plurality of segments. - View Dependent Claims (9, 10, 11, 12)
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13. A security system comprising:
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a watermark detector that is configured to determine an information item from a watermarked segment of watermarked content material and to determine a size of the information item, and an authorization device, operably coupled to the watermark detector, that is configured to determine an authorization of the watermarked segment, based on the information item and based on the size of the information item. - View Dependent Claims (14, 15)
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Specification