US6504941B2
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for digital watermarking of images
Assignee: Hewlett Packard Development Co LP
•
Filing: 1998-04-30
•
Granted: 2003-01-07
•
Expires: 2018-04-30
Abstract
Abstract The present invention provides an invisible digital watermarking technique that can serve the two purposes of ownership verification and authentication, that can detect changes in pixel values as well as image size, and that may be used in public key or alternatively, secret key watermarking systems. The watermark insertion procedure computes a hash function and then combines the output of the hashed function of a modified image block, a key and various image parameters with a block of the watermark bitmap, resulting in a combined image block. As a final step to create a watermarked image block, the combined image block is inserted into the LSB of the modified image. The watermark extraction procedure takes the watermarked image block and creates two different image blocks: a first image,block with the LSB's of the watermarked image block set to zero, and a second image block with the LSB's of the watermarked image block extracted. The watermark extraction procedure uses the hash function to calculate a digest of values, resulting in a hashed output. The hashed output is combined with the second image block, preferably using an exclusive OR function. The result of the combined hashed output with the second image block is a block of the extracted watermark.
Inventors
- 👤 Ping Wah Wong
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 12:42
CPC Classifications
G; G06; G06T; G06T1/00; G06T1/0021; G06T1/0028; G06T1/0035; H; H04; H04N; H04N1/00; H04N1/32; H04N1/32101; H04N1/32144; H04N1/32149; H04N1/32203; H04N1/32208; H04N1/32213; H04N1/32267; H04N1/32283; G06T2201/00; G06T2201/005; G06T2201/0061; H04N2201/00; H04N2201/32; H04N2201/3201; H04N2201/3225; H04N2201/3233; H04N2201/3236; H04N2201/3269; H04N2201/327
Claims Analysis
Total Claims: 41
Claim 1
Independent Claim
234 words
An electronic system for inserting a watermark into a digital image, comprising: means for modifying at least one predetermined bit within an image block X r to a predetermined value, wherein the modified image block is X r ; means for calculating a digest of values using a cryptographic hash function, wherein a user key, an image width, an image height and the modified image block are inputs to the means for calculating a digest of values, wherein the output of the means for calculating a digest of values is a hashed output, wherein the means for modifying at least one predetermined bit of the image block is electrically coupled to the means for calculating a digest of values; means for combining the hashed output with a watermark, wherein the means for combining uses a pixel by pixel exclusive OR logic operation, wherein the means for combining the hashed output with a watermark is electrically coupled to the output of the means for calculating a digest of values, wherein the output of the means for combining is a combined image block C r ; and means for inserting a first image block into the modified image block X r , wherein the means for inserting the first image block into the modified image block X r , is electrically coupled to the means for modifying at least one predetermined it of the image block.
Claim 2
Dependent Claim
234 words
An electronic system for inserting a watermark into a digital image, comprising: means for modifying at least one predetermined bit within an image block X r to a predetermined value, wherein the modified image block is X r ; means for calculating a digest of values using a cryptographic hash function, wherein a user key, an image width, an image height and the modified image block are inputs to the means for calculating a digest of values, wherein the output of the means for calculating a digest of values is a hashed output, wherein the means for modifying at least one predetermined bit of the image block is electrically coupled to the means for calculating a digest of values; means for combining the hashed output with a watermark, wherein the means for combining uses a pixel by pixel exclusive OR logic operation, wherein the means for combining the hashed output with a watermark is electrically coupled to the output of the means for calculating a digest of values, wherein the output of the means for combining is a combined image block C r ; and means for inserting a first image block into the modified image block X r , wherein the means for inserting the first image block into the modified image block X r , is electrically coupled to the means for modifying at least one predetermined it of the image block.
Claim 3
Dependent Claim
20 words
The electronic system recited in claim 1 wherein the first image block is the combined image block C r .
Claim 4
Dependent Claim
38 words
The electronic system recited in claim 2 wherein the means for combining the hashed output with a watermark is electrically coupled to the means for inserting the first image block into the modified image block X r .
Claim 5
Dependent Claim
20 words
The electronic system recited in claim 1 wherein the first image block is an encrypted image block W r .
Claim 6
Dependent Claim
48 words
The electronic system recited in claim 4 further including an encryption means, wherein the encryption means is electrically coupled to both the means for combining the hashed output with a watermark and the means for inserting a first image block into the modified image block X r .
Claim 7
Dependent Claim
37 words
The electronic system recited in claim 1 wherein the means for modifying at least a predetermined bit to a predetermined value modifies the at least one predetermined bit independently for each color plane of the image block.
Claim 8
Dependent Claim
244 words
An electronic system for inserting a watermark into a digital image, comprising: means for modifying at least one predetermined bit within an image block X 1 , to a predetermined value, wherein the modified image block is X r ; means for calculating a digest of values using a cryptographic hash function, wherein a user key, an image width, an image height and the modified image block are inputs to the means for calculating a digest of values, wherein the means for calculating a digest of values is a hashed output, wherein the means for modifying at least one predetermined bit of the image block is electrically coupled to the means for calculating a digest of values wherein the means for modifying at least one predetermined bit modifies the LSB within the image block X r ; means for combining the bashed output with a watermark, wherein the means for combining uses a pixel by pixel XOR logic block, wherein the means for combining the hashed output with a watermark is electrically coupled to the means for calculating a digest of values, wherein the output of the means for combining is a combined image block; and means for inserting a first image block into the modified image block X r , wherein the means for inserting the first image block into the modified image block X r is electrically coupled to the means for modifying at least one predetermined bit of the image block.
Claim 9
Dependent Claim
244 words
An electronic system for inserting a watermark into a digital image, comprising: means for modifying at least one predetermined bit within an image block X 1 , to a predetermined value, wherein the modified image block is X r ; means for calculating a digest of values using a cryptographic hash function, wherein a user key, an image width, an image height and the modified image block are inputs to the means for calculating a digest of values, wherein the means for calculating a digest of values is a hashed output, wherein the means for modifying at least one predetermined bit of the image block is electrically coupled to the means for calculating a digest of values wherein the means for modifying at least one predetermined bit modifies the LSB within the image block X r ; means for combining the bashed output with a watermark, wherein the means for combining uses a pixel by pixel XOR logic block, wherein the means for combining the hashed output with a watermark is electrically coupled to the means for calculating a digest of values, wherein the output of the means for combining is a combined image block; and means for inserting a first image block into the modified image block X r , wherein the means for inserting the first image block into the modified image block X r is electrically coupled to the means for modifying at least one predetermined bit of the image block.
Claim 10
Dependent Claim
167 words
An electronic system for extracting a watermark from a digital watermarked image comprising means for modifying at least a predetermined bit within an image block of the watermarked image to a predetermined value; means for extracting at least a predetermined from the watermarked image block; means for calculating a digest of values using a cryptographic hash function, wherein a user key, an image width, an image height and the modified image block are inputs to the means for calculating a digest of values, wherein the output of the means for calculating a digest of values using a cryptographic hash function is a hashed output, wherein the means for modifying at least a predetermined bit of the watermarked image is electrically coupled to the mans for calculating a digest of values; means for combining, wherein the means for combining is electrically coupled to the output of the means for calculating a digest of values, wherein the means for combining uses a pixel by pixel exclusive OR logic operation.
Claim 11
Dependent Claim
167 words
An electronic system for extracting a watermark from a digital watermarked image comprising means for modifying at least a predetermined bit within an image block of the watermarked image to a predetermined value; means for extracting at least a predetermined from the watermarked image block; means for calculating a digest of values using a cryptographic hash function, wherein a user key, an image width, an image height and the modified image block are inputs to the means for calculating a digest of values, wherein the output of the means for calculating a digest of values using a cryptographic hash function is a hashed output, wherein the means for modifying at least a predetermined bit of the watermarked image is electrically coupled to the mans for calculating a digest of values; means for combining, wherein the means for combining is electrically coupled to the output of the means for calculating a digest of values, wherein the means for combining uses a pixel by pixel exclusive OR logic operation.
Claim 12
Dependent Claim
30 words
The electronic system recited in claim 8 wherein the means for combining is electrically coupled to the means for extracting at least a predetermined bit from the watermarked image block.
Claim 13
Dependent Claim
39 words
The electronic system recited in claim 8 further including a decryption means, wherein the decryption means is electrically coupled to the means for extracting at least a predetermined bit from the watermarked image block and the means for combining.
Claim 14
Dependent Claim
195 words
An electronic system for extracting a watermark from a digital watermarked image comprising: means for modifying at least a predetermined bit within an image block of the watermarked image to a predetermined value; means for extracting at least a predetermined bit from the watermarked image block; means for calculating a digest of values using a cryptographic hash function, wherein a user key, an image width, an image height and the modified image block are inputs tot he means for calculating a digest of values, wherein the output of the means for calculating a digest of values using a cryptographic hash function is a hashed output, wherein the means for modifying at least a predetermined bit of the watermarked image is electrically coupled to the means for calculating a digest of values wherein the means for modifying at least a predetermined bit to a predetermined value modifies the least significant bit of the selected group of pixels within the image block; and means for combining, wherein the means for combining is electrically coupled to the means for calculating a digest of values, wherein the means for combining uses a pixel by pixel exclusive OR logic operation.
Claim 15
Dependent Claim
195 words
An electronic system for extracting a watermark from a digital watermarked image comprising: means for modifying at least a predetermined bit within an image block of the watermarked image to a predetermined value; means for extracting at least a predetermined bit from the watermarked image block; means for calculating a digest of values using a cryptographic hash function, wherein a user key, an image width, an image height and the modified image block are inputs tot he means for calculating a digest of values, wherein the output of the means for calculating a digest of values using a cryptographic hash function is a hashed output, wherein the means for modifying at least a predetermined bit of the watermarked image is electrically coupled to the means for calculating a digest of values wherein the means for modifying at least a predetermined bit to a predetermined value modifies the least significant bit of the selected group of pixels within the image block; and means for combining, wherein the means for combining is electrically coupled to the means for calculating a digest of values, wherein the means for combining uses a pixel by pixel exclusive OR logic operation.
Claim 16
Independent Claim
154 words
A method for inserting a watermark into a digital image including the steps of: partitioning an image block X r into at least one non-overlapping I×J block: for each I×J block, modifying at least a predetermined bit of each I×J block to a predetermined value, wherein the modified image block is X r ; calculating a digest of the values using a cryptographic hash function wherein a user key, an image width, an image height and the modified image block are inputs to the means it, for calculating a digest of values; combining the hashed output calculated in the previous step with a watermark bitmap B r , using a pixel by pixel exclusive or logic operation, wherein the output of the step of combining the hashed output with a watermark B r is a combined image block C r ; and inserting a first image block into the modified image X r .
Claim 17
Independent Claim
154 words
A method for inserting a watermark into a digital image including the steps of: partitioning an image block X r into at least one non-overlapping I×J block: for each I×J block, modifying at least a predetermined bit of each I×J block to a predetermined value, wherein the modified image block is X r ; calculating a digest of the values using a cryptographic hash function wherein a user key, an image width, an image height and the modified image block are inputs to the means it, for calculating a digest of values; combining the hashed output calculated in the previous step with a watermark bitmap B r , using a pixel by pixel exclusive or logic operation, wherein the output of the step of combining the hashed output with a watermark B r is a combined image block C r ; and inserting a first image block into the modified image X r .
Claim 18
Dependent Claim
19 words
The method recited in claim 12 wherein the first image block is the combined image block C r .
Claim 19
Dependent Claim
19 words
The method recited in claim 12 wherein the first image block is an encrypted image block W r .
Claim 20
Dependent Claim
33 words
The method recited in claim 12 further including the step of encrypting the combined image block, wherein the result of encrypting the combined image block is the encrypted image block W r .
Claim 21
Dependent Claim
26 words
The method recited in claim 12 wherein the at least one predetermined bit of the image block X r is modified by discarding the predetermined bit.
Claim 22
Dependent Claim
38 words
The method recited in claim 12 wherein for the step of modifying at least one predetermined bit of the image block X r a plurality of bits are modified by setting the plurality of bits to predetermined values.
Claim 23
Dependent Claim
20 words
The method recited in claim 12 wherein the predetermined bit modified is the LSB within image block X r .
Claim 24
Independent Claim
143 words
A method for extracting a watermark into a digital image including the steps of: for each partitioned non-overlapping I×J block of a watermarked image X r , modifying at least a predetermined bit of each I×J block to a predetermined value, wherein the modified image block is Z r ; calculating a digest of the values using a cryptographic hash function, including providing a user key, an image width, an image height and the modified image block input to the means for calculating a digest of values; for each I×J block, extracting at least a predetermined bit from the watermarked image X r ; decrypting the output of the previous step using a public key decryption function, combining the output of the cryptographic hash function with the decrypted image of the previous step, including using a pixel by pixel exclusive OR logic operation.
Claim 25
Independent Claim
143 words
A method for extracting a watermark into a digital image including the steps of: for each partitioned non-overlapping I×J block of a watermarked image X r , modifying at least a predetermined bit of each I×J block to a predetermined value, wherein the modified image block is Z r ; calculating a digest of the values using a cryptographic hash function, including providing a user key, an image width, an image height and the modified image block input to the means for calculating a digest of values; for each I×J block, extracting at least a predetermined bit from the watermarked image X r ; decrypting the output of the previous step using a public key decryption function, combining the output of the cryptographic hash function with the decrypted image of the previous step, including using a pixel by pixel exclusive OR logic operation.
Claim 26
Dependent Claim
20 words
The method recited in claim 19 wherein the predetermined bit modified is the LSB within image block X r .
Claim 27
Dependent Claim
238 words
An electronic system for inserting a watermark into a digital image, comprising: a system for modifying at least one predetermined bit within an image block X r to a predetermined value, wherein the modified image block is X r ; a system for calculating a digest of values using a cryptographic hash function, wherein a user key, an image width, an image height and the modified image block are inputs to the means for calculating a digest of values, wherein the output of the system for calculating a digest of values is a hashed output, wherein the system for modifying at least one predetermined bit of the image block is electrically coupled to the system for calculating a digest of values; a system for combining the hashed output with a watermark, wherein the system for combining uses a pixel by pixel exclusive OR logic operation, wherein the system for combining the hashed output with a watermark is electrically coupled to the output of the system for calculating a digest of values, wherein the output of the system for combining is a combined image block C r ; and a system for inserting a first image block into the modified image block X r , wherein the system for inserting the first image block into the modified image block X r , is electrically coupled to the system for modifying at least one predetermined bit of the image block.
Claim 28
Dependent Claim
238 words
An electronic system for inserting a watermark into a digital image, comprising: a system for modifying at least one predetermined bit within an image block X r to a predetermined value, wherein the modified image block is X r ; a system for calculating a digest of values using a cryptographic hash function, wherein a user key, an image width, an image height and the modified image block are inputs to the means for calculating a digest of values, wherein the output of the system for calculating a digest of values is a hashed output, wherein the system for modifying at least one predetermined bit of the image block is electrically coupled to the system for calculating a digest of values; a system for combining the hashed output with a watermark, wherein the system for combining uses a pixel by pixel exclusive OR logic operation, wherein the system for combining the hashed output with a watermark is electrically coupled to the output of the system for calculating a digest of values, wherein the output of the system for combining is a combined image block C r ; and a system for inserting a first image block into the modified image block X r , wherein the system for inserting the first image block into the modified image block X r , is electrically coupled to the system for modifying at least one predetermined bit of the image block.
Claim 29
Dependent Claim
21 words
The electronic system recited in claim 21 , wherein the first image block is the combined image block C r .
Claim 30
Dependent Claim
21 words
The electronic system recited in claim 21 , wherein the first image block is an encrypted image block W r .
Claim 31
Dependent Claim
39 words
The electronic system recited in claim 21 , wherein the system for combining the hashed output with a watermark is electrically coupled to the system for inserting the first image block into the modified image block X r .
Claim 32
Dependent Claim
247 words
An electronic system for inserting a watermark into a digital image, comprising; a system for modifying at least one predetermined bit within an image block X r to a predetermined value, wherein the modified image block is X r ; a system for calculating a digest of values using a cryptographic hash function, wherein a user key, an image width, an image height and the modified image block are inputs to the system for calculating a digest of values, wherein the system for calculating a digest of values is a hashed output, wherein the system for modifying at least one predetermined bit of the image block is electrically coupled to the system for calculating a digest of values wherein the system for modifying at least one predetermined bit modifies the LSB within the image block X r ; a system for combining the hashed output with a watermark, wherein the system for combining uses a pixel by pixel XOR logic block, wherein the system for combining the hashed output with a watermark is electrically coupled to the system for calculating a digest of values, wherein the output of the system for combining is a combined image block; and a system for inserting a first image block into the modified image block X r , wherein the system for inserting the first image block into the modified image block X r is electrically coupled to the system for modifying at least one predetermined bit of the image block.
Claim 33
Dependent Claim
247 words
An electronic system for inserting a watermark into a digital image, comprising; a system for modifying at least one predetermined bit within an image block X r to a predetermined value, wherein the modified image block is X r ; a system for calculating a digest of values using a cryptographic hash function, wherein a user key, an image width, an image height and the modified image block are inputs to the system for calculating a digest of values, wherein the system for calculating a digest of values is a hashed output, wherein the system for modifying at least one predetermined bit of the image block is electrically coupled to the system for calculating a digest of values wherein the system for modifying at least one predetermined bit modifies the LSB within the image block X r ; a system for combining the hashed output with a watermark, wherein the system for combining uses a pixel by pixel XOR logic block, wherein the system for combining the hashed output with a watermark is electrically coupled to the system for calculating a digest of values, wherein the output of the system for combining is a combined image block; and a system for inserting a first image block into the modified image block X r , wherein the system for inserting the first image block into the modified image block X r is electrically coupled to the system for modifying at least one predetermined bit of the image block.
Claim 34
Dependent Claim
38 words
The electronic system recited in claim 25 , wherein the system for modifying at least a predetermined bit to a predetermined value modifies the at least one predetermined bit independently for each color plane of the image block.
Claim 35
Dependent Claim
49 words
The electronic system recited in claim 25 , further including an encryption system, wherein the encryption system is electrically coupled to both the system for combining the hashed output with a watermark and the system for inserting a first image block into the modified image block X r .
Claim 36
Dependent Claim
173 words
An electronic system for extracting a watermark from a digital watermarked image comprising: a system for modifying at least a predetermined bit within an image block of the watermarked image to a predetermined value; a system for extracting at least a predetermined bit from the watermarked image block, a system for calculating a digest of values using a cryptographic hash function, wherein a user key, an image width, an image height and the modified image block are inputs to the system for calculating a digest of values, wherein the output of the system for calculating a digest of values using a cryptographic hash function is a hashed output, wherein the system for modifying at least a predetermined bit of the watermarked image is electrically coupled to the system for calculating a digest of values; and a system for combining, wherein the system for combining uses a pixel by pixel exclusive OR logic operation, wherein the system for combining is electrically coupled to the output of the system for calculating a digest of values.
Claim 37
Dependent Claim
173 words
An electronic system for extracting a watermark from a digital watermarked image comprising: a system for modifying at least a predetermined bit within an image block of the watermarked image to a predetermined value; a system for extracting at least a predetermined bit from the watermarked image block, a system for calculating a digest of values using a cryptographic hash function, wherein a user key, an image width, an image height and the modified image block are inputs to the system for calculating a digest of values, wherein the output of the system for calculating a digest of values using a cryptographic hash function is a hashed output, wherein the system for modifying at least a predetermined bit of the watermarked image is electrically coupled to the system for calculating a digest of values; and a system for combining, wherein the system for combining uses a pixel by pixel exclusive OR logic operation, wherein the system for combining is electrically coupled to the output of the system for calculating a digest of values.
Claim 38
Dependent Claim
31 words
The electronic system recited in claim 28 , wherein the system for combining is electrically coupled to the system for extracting at least a predetermined bit from the watermarked image block.
Claim 39
Dependent Claim
40 words
The electronic system recited in claim 28 , further including a decryption system, wherein the decryption system is electrically coupled to the system for extracting at least a predetermined bit from the watermarked image block and the system for combining.
Claim 40
Dependent Claim
193 words
An electronic system for extracting a watermark from a digital watermarked image comprising: a system for modifying at least a predetermined bit within an image block of the watermarked image to a predetermined value; a system for extracting at least a predetermined bit from the watermarked image block; a system for calculating a digest of values using a cryptographic hash function, wherein a user key, an image width, an image height and the modified image block are inputs to the system for calculating a digest of values, wherein the output of the system for calculating a digest of values using a cryptographic hash function is a hashed output, wherein the system for modifying at least a predetermined bit of the watermarked image is electrically coupled to the system for calculating a digest of values, wherein the system for modifying at least a predetermined bit to a predetermined value modifies the least significant bit within the image block; and a system for combining, wherein the system for combining uses a pixel by pixel exclusive OR logic operation, wherein the system for combining is electrically coupled to the system for calculating a digest of values.
Claim 41
Dependent Claim
193 words
An electronic system for extracting a watermark from a digital watermarked image comprising: a system for modifying at least a predetermined bit within an image block of the watermarked image to a predetermined value; a system for extracting at least a predetermined bit from the watermarked image block; a system for calculating a digest of values using a cryptographic hash function, wherein a user key, an image width, an image height and the modified image block are inputs to the system for calculating a digest of values, wherein the output of the system for calculating a digest of values using a cryptographic hash function is a hashed output, wherein the system for modifying at least a predetermined bit of the watermarked image is electrically coupled to the system for calculating a digest of values, wherein the system for modifying at least a predetermined bit to a predetermined value modifies the least significant bit within the image block; and a system for combining, wherein the system for combining uses a pixel by pixel exclusive OR logic operation, wherein the system for combining is electrically coupled to the system for calculating a digest of values.
References Cited (Backward Citations)
US5231668A
Cited
US5651069A
Cited
US5530759A
Cited
US5613004A
Cited
US5664016A
Cited
US5608801A
Cited
US5870470A
Cited
US5949885A
Cited
US5915027A
Cited
US6009176A
Cited
US5995625A
Cited
US6064764A
Cited
US6256736B1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2006-01-06 | 2006-07-08 | 2007-01-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2010-01-06 | 2010-07-08 | 2011-01-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2014-01-06 | 2014-07-08 | 2015-01-07 | $7700.00 | Window Closed / Lapsed |