TW580656B - Protection and verification method for digital image copyright - Google Patents

Abstract

The invention relates to a protection and verification method for digital image copyright, which use discrete cosine transform (DCT) technique to acquire the discrete cosine value of each intended protection image as characteristic value; further use the characteristic value of the image and watermark image contents to mutually combine using exclusive-or (XOR) operation and generate a secret gold key. Legal user can hold the secret gold key to abstract the watermark image of the protected image, and after registering the secret gold key to equitable third party to generate secret gold key with timestamp to approve the time sequence of ownership by the image. The invention integrates algorithm method in generation of secret gold key to calculate the secret gold key of original image and the algorithm method for abstracting watermark used to abstract watermark image from protected image based on the secret gold key.

Description

Nine, Ming age out (looking: inverting two tear Chou, sickle surface, with, face city fibrillated single description) a technical field relevant to the invention is based the present invention on the protection and authentication method for a digital image copyright 'especially a growing number of digital watermarking method with the notary's verification of the bit image based on copyright. Second, the prior art by 'the technological development of information rapidly, and Internet popularization' There are more and more commercially valuable multimedia information in, week Coloane & propagation, such as a picture (graph), image (image ), music (audio), and video (vide〇), etc., issued by the user can simply and easily download an instruction in a network. However, there are some users after conventional after downloading the multimedia information, which is claimed to be tampered with their own data 'to make profit their business practices, this has seriously violated the raw data of the owner of intellectual property rights, and therefore , dissemination of information on the Internet must have measures to protect intellectual property rights, in order to make the ownership of the people get perfect protection. In order to solve the problem of valuable multimedia information theft and tampering with, the conventional system for cryptography (crypt〇graphy), hidden information (data hiding), digital image copyright protection (image copyright protection), and digital watermark (digital watermarking) to study technology, with a view to identify effective protection measures. In the fork code technology, it includes encryption, digital signature, and timestamp. It can be used to provide security protection of intellectual property rights, but it is not suitable for processing multimedia 580656 data. 'Because of multimedia data The broadcast size is usually much larger than the text, and it takes a lot of time to encrypt or sign with ordinary cryptographic techniques. In addition, the general encryption and signature methods do not allow distortion, but as long as the distortion of multimedia data is acceptable, In the following, distortion situations can be allowed. Therefore, the most widely used method is the use of digital watermarking technology and digital image copyright protection technology. Digital watermarking technology refers to adding a totem (such as a registered trademark, a uniform number of a for-profit business, a personal portrait, etc.) representing a legal owner to the protected valuable media to indicate and prove the legal ownership of the media. And after the watermark embedded media is processed and destroyed by some common digital signals, and the quality is within acceptable range, the watermark can still be displayed, so it can prove the copyright ownership of this media to find out Theft or counterfeiting by illegal users. The conventional digital watermarking technology must have the following characteristics: Transparency, so that there is no obvious change between the watermarked media and the original media, that is, people do not notice the existence of the watermark in the media. ; 5 ⑽ustness): When the watermarked media undergoes digital signal processing (such as blurring, sharpening, distortion shrinking, adding noise to image cutting, zooming, or rotating processing, etc.), the quality is acceptable watermark still be within the scope of the show ... clarity of the two b Γ • Γ ii) digital watermarking technology in a variety of possible attacks condition: broken pounds out of the ocean watermark image must be able to clearly identify itself as the commercial value == ; Security (security): hidden == Yin algorithm is an open algorithm; the original data (bnndness) when removing floating water: usually digital media requires COS204 7 580656 storage, in order to save space, so remove the watermark when, 3 can be completed by the secondary of the original media, i.e. without the need to float while the original storage medium, - and a practical method :: 7 different impressions must have performed better efficiency In order to achieve high availability. 2 'In the conventional digital watermarking technology, if someone is engraved with the m! Watermarking algorithm to attack, the digital watermark hidden in the body is reversed; if it is destroyed in the same media = person plural watermark, it is difficult to rhyme real rightful owners: also, conventional data amount occupied by the larger technology, but also the processing costs: Thus also proposed another conventional practice for the media feed ΓΓ more important as the characteristic value 'using - dedicated resources stored in the characteristic value to match the image 2 and f _ wherein the feed medium' to check this media is d book 'However, this feature can only identify whether the information has not registered as part = number of material watermarking technology - y proofs can be visually identify out, it is equally difficult to prove the real owner of intellectual property rights. Digital video protection technology is still missing and there are many necessary improvements have to be made known to be 4%. Third, the present invention SUMMARY ▲ tt you "line out of the main object to provide - kind of copyrighted digital image s ,: security authentication method, to ensure Bineng protected media robustness to withstand a variety of attack conditions. Another β present invention - to provide object-based digital image species _ copyright protection af test method to enabling the protected media quality of the original media and the same product quality. vGS265 8 further - provide object-based - kind of digital image copyright protection = verification method based legitimacy by a fair third party to register to produce a time stamp signature in accordance with a secret when Kingland chapter = 'to judge the body of the . , The above-mentioned object, a digital image of the present invention proposed copyright protection ^ stay and verification method mainly comprises the first - and second program procedure. the first

System for generating a sequence ^ - Secret painted, it is first captured - and an original image: image watermark, wherein the original image is multiplied by the picture element Ming 'V 〇w picture element of the image, a watermark image is Wh FIG. Multiply the image by ^ pixels, and 0H is the height of the original material, 0w is the width of the original image, Wh is the south of the floating 7-shirt image 'WwA the width of the watermark image; then the original image < is WHxWw blocks; n and discrete cosine conversion techniques to

Each one of the values into - a frequency-domain coefficient blocks Shu scrambled random number and then to the frequency domain coefficient blocks; then, taken out operation of the DCT coefficient value block in the frequency domain after the above-mentioned upset to the WWW discrete cosine value formed - the discrete cosine series; and after the discrete cosine series sorted - generating preset the threshold - temporary gold I; Finally, the temporary key and with the feed printing image exclusive OR operation to produce - secret catalog 'to convert the original image - an image embedded with a protective apart secret. The second procedure is to extract the watermark image from the protective image towel, which first captures-protects the image; cuts the protected image into WWW blocks; and then makes Han Sanling forward to pure technology to convert the value of each block is - a frequency-domain coefficient blocks; Next, random number scrambled blocks of frequency domain coefficients; _ and frequency-domain coefficient blocks of discrete cosine values ± out of said spin to the discrete cosine WhXWw formed a form

C526S 9 a discrete cosine series; after sorting discrete cosine value series; and retrieved from the secret key out a threshold, then after deducting the threshold secret key is stored as a first temporary key; then according to the ranking The subsequent discrete cosine value sequence and threshold value are used to generate a second temporary key; finally, the first temporary key and the second temporary key are mutually exclusive to extract a watermark image to be tested. Fourth, implementation mode In order to allow your review committee to better understand the technical content of the present invention, a preferred embodiment is described below. Use of the present embodiment based discrete cosine transform (Discrete Cosine Transform, DCT) technique of n discrete cosine conversion (Forward DCT) method to get the discrete cosine value of each image to be protected (Discrete Cosine, DC) as a characteristic value, then The feature value of the image and the content of the watermark are combined to generate a secret key, so the legitimate owner of the image can hold the secret key to extract the watermark, and can transfer the secret gold to a fair third registration, resulting signature stamp of when a key has to pass through it when the secret key and a key with a signature stamp to prove ownership of the copyright of the image. See Figure 1 for the process of generating a secret key in the original image. In this embodiment, the original image 0 is composed of a grayscale image with cold bits per pixel, and the watermark image W is shown in FIG. 2, which is a binary image and the original The definitions of image 0 and watermark image W are: 0 = {〇Μ | 0 < 〇Μ < 2β ~ ΐ} ^ 580656

Among them, each 〇i, j is a pixel, 0 O Oh-j, 〇sjs〇w -1, and 〇H is the height of the original image 0, which is the width of the original image 0; w = {wijlwij ^ M} Among them, each wu is a pixel kbWh-i, ten, and WH is the height of the watermark image W, and ww is the width of the watermark image W. Therefore, after (step S101) retrieve the original watermark image and a square image W, the original image is cut into square blocks Bmn WHxWw a proportional watermark image according to the aspect ratio of the boundary (step S102), and each block size

Determinant: The above-mentioned proportional block Bm n is recorded as follows

Square, l.J + W-l 〇iJ ° i, j + l ®i + l, j + w-l

m, n " " • · · «« _ ° i + h-l, j ... among 11. It should be noted that, in this embodiment, the original image is preferably cut into equal-scale blocks, and of course, it can also be cut into blocks of different proportions, as long as the number of cut-out blocks is equal to WHxWw. Again, the rear cut WHxWw block Bm, n, from the digital data of a spatial domain through discrete cosine conversion timing (the FDCT) technology to convert into frequency domain coefficients Cm, n (step S103), thereby obtaining the mother 'special The eigenvalues of the proportional block Bm n, among which 〇 幺 mSWH-1, 〇SnSWw-1; then use the random seed number to disturb the arrangement order of the frequency domain blocks (step S104); and take out each frequency-domain coefficient blocks C 'm, n discrete cosine (DC) value (step S105), the total can be obtained WHxWw discrete cosine Λ ·, Q 〇Aw Ο 〇11 580656

Value 'thus a discrete cosine values Dm n columns are formed; WhX after the discrete cosine value series Dm, n becomes the descending order of the sorted column discrete cosine values DSm, n (step si〇6). Next '^^ columns according to the number of the discrete cosine sorted ,. And of a predetermined threshold (hereinafter referred to as TH) of FIG generating temporary key T (step S107) shown in FIG. 3: Τ = Κ, η I tm, n ^ {}} 〇5l wherein KmSWH-1,? (^ N: iWwM, and when the number before DSmn (the total number of THx blocks) is set to 1 on the relative block of Dm, n, tm n is 丨; after DSm, n (the total number of blocks is one (ΤΗχ when the number of the total number of blocks)) is set to the square on the opposite block, 〖_ 0. Further, the threshold value TH by the legitimate users control over and to follow a characteristic of each image to set different thresholds TH, in order to determine the number of temporary key D with 1 billion by the threshold TH, but for security reasons, so it is not advisable to set the threshold 711 too low or the south 'preferred system to between 1.2 billion After the temporary key is obtained from the original image 0, it can be used for the exclusive_〇R operation with the temporary 2 key τ and the watermark image w to generate as shown in Figure 4. the secret key foot (step sl〇8), where: K = (T0W) || TH Further, the original image points in time to declare billion arising, will thus: the secret The key K is registered with a fair third party to generate a key 1 with a time stamp signature (step S109), which can solve the problem of who adds the watermark image w first, and the above-mentioned key core with a time stamp signature It is secured by a fair third party. From this, it can be seen that the method of this embodiment does not directly embed the watermark image W in the original image when it is hidden in the watermark image W Temple. CS2G9 12 580656 is generated separately. a secret key κ, they are able to ensure the protection of: ⑽ like the quality and the original image 〇_ kind of good, and by having a better jab early sign of heart when the key to prove that the order to eliminate the controversy, in fact, Great progress. Therefore, when you want to extract the watermark image in the protected image, please refer to the process in Figure 5. After extracting the protected image s (watermarked_㈨) (step S501), the protected image 8 is also based on the watermark image. aspect ratio w is cut into a proportional WHxWw blocks Bm n (step S5〇2), wherein 〇SmSWH -1 'square < nsww-1, the size of each block of the soil, to protect and WH Ww SH high image s, Sw s broad to protect the image. Next _ 'in step S502 of FIG. 5 The flow of step S506 is the same as that of steps S102 to S106 in FIG. 1, so it will not be repeated, except that in FIG. 5, the target is the protection image S, and the target in FIG. 1 is the original image. in step S507, the original image from the original extraction according to the square of the calculated secret key K, which corresponds to the threshold of τη, and the secret key K to obtain deducting the threshold value TH as shown in FIG. 6 of the first Temporary key T1 (step S508); Then, according to the sorted discrete cosine value sequence Dsmn and a preset threshold value (hereinafter referred to as TQ), a second temporary key T2 as shown in FIG. 7 (step 8509): Τ2 = {νηΙΐΜ〇, ι}}, where, 0 < mSWH-1, 〇SnSWw-l, and the number (ΤΗχ total number of blocks) is set on the opposite block of Dm, n before the DSm, n When it is 1, tm, n is i; when the number after DSm, n (DSm, n — (THx block total)) is set to 0 on the relative block of Dm, ni, tm, n is 0. ,, r.

13. In the last two, the first temporary key T1 and the second temporary key D2 are interoperated ^ P to extract the watermark image W to be tested as shown in FIG. 8 (step 510). The calculation method is: ψ, = (τΐφτ Magic. If the protection image $ is not broken, W will be equal to w; otherwise there may be a slight difference between the two. It is calculated using the bit correct ratio (BCR) method similarity between the two: xioo% »_ Σ, Γ Σ ^ Γ wcijJewYi, j) where 'W (i, j) in the original watermark image boundary ⑽ bit values of the coordinates, w' (i, j)! The bit value of the watermark image w 'at the coordinates (^) to be measured. According to the above description, it is shown that the digital image copyright protection and verification method proposed by the present invention can affect the premise of the original image quality:' according to the original image to produce than gold secrets; and are able to generate keys have time to kill signature by registering impartial third party, in order for the legal system earlier than those who registered for the prevent abuses such as Du imitation f ; and if the attacker claimed that he has the legal copyright owner of the image, you can not extract a clear float attacker Watermarking shows that the method of the present invention can ensure the robustness of the protected media 'to withstand various attack conditions; moreover, it is not necessary to use the original data in the process of extracting the watermark image, and save outside, others can not _ the possession of this video watermark 'penetration is a big step forward. The above embodiments are merely examples for the convenience of explanation. The scope of the claims of the present invention shall be subject to the scope of the patent application, and is limited to the above embodiments. V. Brief Description of the drawings Figure 1 is an embodiment 580656 a flow chart of the secret key is generated according to the present invention. FIG. 2 is a schematic diagram of a watermark image according to an embodiment of the present invention. Figure 3 is a schematic diagram of a temporary key according to an embodiment of the present invention. FIG. 4 is a schematic diagram of a secret key according to an embodiment of the present invention. Figure 5 is a flow chart an embodiment of the present invention the extraction of the watermark image. A schematic view of the first temporary key based embodiment of FIG. 6 embodiment of the present invention. FIG 7 schematic view showing a second embodiment of a temporary key embodiment of the present invention. FIG. 8 is a schematic diagram of a watermark image to be measured according to an embodiment of the present invention. Drawing number description

Original image 〇 Watermark image W

Temporary key Secret key K T S first temporary protection key image T1 T2 second temporary key test watermark image W '·

15

Claims (1)

Pick, patent range comprising: Species digital image copyright protection and authentication method, the main program package t, to generate - Secret recorded, comprising the steps of: taking - the original image and - an image watermark, wherein, the "Γ !: Is an image of 0h pixels multiplied by 0w pixels, and the starting image of the watermark: :: H pixels multiplied by pixels, where 0h is the original seal: de z degrees' ^ is the original the width of the image, ^ for the dimension of the float, ww for the width of the watermark image; (A2) the original image is cut into blocks WhxW~; (A3) n discrete cosine transformation, the each zone The value of the block is converted into a frequency domain block coefficient; (A4) The order of the frequency domain block coefficients is disturbed with random numbers; (A5) #The member takes out the frequency of the block coefficients after the disruption, such as Yanhai. Discrete, 5-valued to form a discrete cosine sequence from WHxWw discrete cosine values; '(A6) sort the discrete cosine value sequence; (A7) generate the discrete cosine value sequence after the sorting and a preset threshold value to generate a temporary key; and (A8) the temporary key and the watermark image with Repel operation to generate a secret key to convert the original image into a protected image embedded with the secret key; and a second procedure for extracting a Wh pixel by a Ww pixel from a protected image the watermark image, wherein the image protection system having a Ki > i U 580656 secret key, for the height wH watermark image, the image of the watermark of width Ww, comprising the steps of: (B1) to retrieve A protected image; (B2) cut the protected image into wHxWw blocks; (B3) use discrete cosine transform technology to convert the value of each block into a frequency domain block coefficient; (B4) use random numbers Shuffle the order of the block coefficients in the frequency domain; (B5) Extract the dispersion of the block coefficients in the frequency domain after scrambling Cosine to the WHxWw discrete cosine values to form a form a discrete cosine series; (B6) sorting the discrete cosine series; (B7) retrieving a threshold value from a secret key, and the deduction of the rocker The secret golden coin after the value is stored as a first temporary key; (B8) A second temporary key is generated according to the sorted sequence of discrete cosine values and the threshold value; and a repel operation is used to extract a test object. watermark images. The method described in item 1 of the patent scope of Rushen Beta Month, the original image of the basin is called Ojlo "^ 2p_1}, and each Olj system is a voxel, t — the pixel system has a record, and the In the method described in item 2, the original image is a grayscale image. The method described in item 2 of the floating range is a binary image W + A, where j '' pixels, . Bu 〇SjsW .C3274 hoot and method of w 17 580656, wherein, in, and each block 5. the range of the patent application step (A2), the first item Shu, the size of each block is & square i, j ° ij + i 0 is called 〇i + l, j + l O .. l.J + Wl Ο. f. I + 1, J + W-1 'among ο Ο i + h-1, j + w ~ l 〇 < n < Ww- 6. The method of application of paragraph 1 patentable scope, Ju in step ⑽, the balance being gold temporarily seven Shu T ,, which bone dagger 'square as Ww], and when the prior DSMN (multicast gate value X when the number of the total number of blocks) is set to i in the block on the opposite Dni, n ,, when the DSm, n (total number of blocks - the number (total number of blocks threshold χ "of the ^ provided on the opposite block ^ is called, tm ^ G, and the DSm, 々 rear of the ranking discrete cosine series, Dm, n number of columns for a discrete cosine value. 7. the application method according to the item 1 patentable scope, wherein, in step ( A8), the secret more than for κ = (Τφ · τΗ, which, as Ding β temporary key, w for the video watermark, ΤΗ values for Tan door. 8. The method according to item 1 of the scope of patent application, wherein in step (B8), the second temporary key is called. ',}}, Among them, 0 plus Ww-1, and when the number before DSm, n (threshold value counterfeit ghost ^ heart number) is set to i on the relative block of Dm n, u ^ is 1' When DSm, n (DSmn— (threshold value ※ total number of blocks) is set to 0 on the relative block of 0_, 'is 0, and the team ’s sequence of discrete cosine values after the order, Dm, ” the discrete cosine series * f 'square | 18 580656 9 · Fangbu as the application of paragraph 8 patentable scope _), the test image is watermark ^ ⑽: L T1 is 6 in the first temporary Hai key, _ [tau] 2 is the second provisional patent application as to the range of the first item after the step (iv)〗 still comprises a step (the A9), its density; impartial third party registered in two, to produce - with - time. 1 to a range of the patent application as in item i, I ° correct bit rate than the original method ,, ^ floating system using the image similarity. "image and the watermark test &Amp; The application of the method according to item patentable scope u, wherein, the correct bit rate = the law, w (i, j) for the original watermark image here, the test for the watermark image at coordinates (i , Janus-faced Department: ,, wherein the step 14. the two patented range : G_S 19