# The method of applying a watermark in a digital image

The invention relates to the application of a watermark in a digital image. Perform merging data sets of the base image and sets the image data of the signature to a pre-defined way of combining the aggregates so that they are linearly independent. Form the watermarked image and the key from the merged image. The image of the signature included in the merged image, is similar to the combined image from the point of view of availability and resilience to external factors. The technical result is increased reliability of separation of one data type from another. 8 C. and 27 C.p. f-crystals, 3 ill.The technical field to which the invention relatesThe present invention relates to the application of watermarking, and more specifically the method of applying a watermarking digital images.Prior artThe application of digital watermarking is a method of introducing a bit pattern, which is called signature information in a digital image or audio and video files to identify images or files in kachestvennie copyright protection. In that case, when secured by copyright material based on videomaterial, application of digital watermarks develop so that the signature information is invisible. In that case, when secured by copyright material based on audiomaterial, application of digital watermarks develop so that the signature information is inaudible. In addition, the signature information should be evenly distributed around the source file, so that it could not identify or her to manipulate users. Next, the signature information should be fairly stable, with the goal of keeping the total changes made to a source file, such as volume reduction caused by the compression algorithm.Fig.1 illustrates a conventional method of applying a watermark in a digital image. Considering Fig.1, note that by the usual method of applying a watermark in a digital image the main image and the image of the signature is converted to the Fourier coefficients by means of the fast Fourier transform (FFT), and not only the coefficients of the transformed image signatures, but also the password or key attached the image, by doing this the application of watermarks. Watermarked image is divided into the coefficients of the main image and the coefficients of image signatures using a password or key for separation. Next, the divided coefficients are subjected to inverse fast Fourier transform (OBPF) by receiving the main image and the image of the signature, respectively.In accordance with another conventional method of digital drawing watermark image signatures and the main image is also converted to wave coefficients by discrete wavelet transformation (DWT), and wave coefficients of image signatures join the wave spatial domain is transformed main image by performing the application of watermarks.However, according to the usual methods of applying watermarks, since the formation of the coefficients of image signatures embedded in the coefficients of the main image based on the arithmetic sum of the two coefficients at each point of the image element, the reliability of the formation cannot be achieved. That is, if the combined image is subjected to the MMA can vary so much, one type of data becomes impossible to separate from another data type. Similarly, if the combined image is subjected to a moderate image processing two or more times, the arithmetic sum can vary so much that one type of data cannot be separated from another data type.The inventionThe first objective of the present invention is the provision of a method of applying a watermark in a digital image to perform applying watermarks so that the image signatures, introduced in the merged image was similar to the combined image, from the point of view of its availability and resistance to external factors).The second objective of the present invention is the provision of a method of encoding a digital image, comprising the method of applying a watermark in a digital image.A third objective of the present invention is the provision of machine-readable recording media for storing program codes for performing the method of applying a watermark in a digital image.The fourth objective of the present invention is the provision of a method of decoding zienia.The fifth objective of the present invention is the provision of a processor (processing unit) applying a watermark in a digital image for execution of the application watermark so that the image signatures, introduced in the merged image was similar to the combined image in the sense of availability and stability.The sixth objective of the present invention is the provision of a device of encoding a digital image, comprising a processor applying a watermark in a digital image.The seventh objective of the present invention is the provision of a decoding device of a digital image for decoding the image encoded by the encoding method of the digital image.Accordingly, to solve the first task is provided a method of applying a watermark in a digital image, comprising the steps of combining the data sets of the base image and sets the image data of the signature to a pre-defined way of combining the aggregates, so that they are linearly independent, and the formation of the watermarked image and the key from the United sobrat phase extraction image signature from the watermarked image, using the key.In accordance with another aspect of the present invention is provided a method of applying a watermark in the digital form of the invention, comprising the steps: (a) insert (fill) of predetermined values of the picture elements between the respective data sets of the image data of the signature so that the aggregate size of the image data of the signature was the same as the size of the population data of the main image, (b) establishment of completed data sets of image signatures in the form of aggregates wave coefficients of the wave functions, (C) establish sets of data of the main image in the form of sets of scaling factors scaling functions, and (d) conversion of vibratory wave coefficients and sets of scaling factors in the form of sets of scaling factors at one level, above level, which belong to two groups, in accordance with a predetermined algorithm, wavelet transformation, in which the aggregate wave coefficients and the set of scaling factors are set with linear independence.ZAR is lenny algorithm wavelet transformation may include the step of alternating the location of the sets of coefficients of the wave coefficients and coefficients of sets of scaling factors.The method of applying a watermark in a digital image may also include the step (e) formation of the watermarked image and the key from the transformed sets of scaling factors.The method of applying a watermark in a digital image preferably includes the additional step (f) extracting image signature from the watermarked image using the key.To solve the second task is provided a method of encoding a digital image, comprising the method of applying a watermark in a digital image.To solve the third problem is provided machine-readable recording medium for storing program codes for performing the method of applying a watermark in a digital image, comprising the steps: (a) inserting predetermined values of the picture elements between the respective data sets of the image data of the signature so that the aggregate size of the image data of the signature was the same as the size of the population data of the main image, (b) establishment of completed data sets of the image signals is ESD images as sets of scaling factors scaling functions, and (d) conversion of vibratory wave coefficients and sets of scaling factors in the form of sets of scaling factors at one level, above level, which belong to two groups, in accordance with a predetermined algorithm, wavelet transformation, in which the aggregate wave coefficients and the set of scaling factors are constructed linearly independent.To solve the fourth problem is provided a method of decoding a digital image for decoding the image encoded by the encoding method of a digital image, comprising the step of the method of applying a watermark in a digital image with the purpose of combining data sets of the base image and sets the image data of the signature to a pre-defined way of Association, by which the aggregate data of the main image and the combined image data signatures are combined linearly independent manner, and to form the watermarked image and the key from the combined image, and a method of decoding a digital image includes a step of extracting depicted is the tasks provided by the processor (processing unit) applying a watermark in a digital image, includes a filling unit for inserting predetermined values of the picture elements between the respective data sets of the image data of the signature so that the aggregate size of the image data of the signature is the same as the size of data sets of the base image, the first node to setup completed data sets of image signatures in the form of aggregates wave coefficients of the wave functions, the second node installation to install the data sets of the base image in the form of sets of scaling factors scaling functions and site conversion for converting vibratory wave coefficients and sets of scaling factors in the form of sets of scaling factors at one level above the level owning two together, in accordance with a predetermined algorithm, wavelet transformation, in which the aggregate wave coefficients and the set of scaling factors are linearly independent way.To solve the sixth task is provided a device for encoding a digital image, sod is provided a decoding device of a digital image to decode the image, encoded by encoding a digital image containing the runtime of the method of applying a watermark in a digital image to perform the method of applying a watermark in a digital image with the purpose of combining data sets of the base image and sets the image data of the signature to a pre-defined way of Association, by which the aggregate data of the main image and the combined image data signatures are combined linearly independent manner, and to form the watermarked image and the key from the combined image, and the decoding device of a digital image contains a decoding device for extracting image signature from the watermarked image using the key.Brief description of drawingsThe above objectives and advantages of the present invention will become more apparent from the detailed description of a preferred option implementation with reference to the accompanying drawings, on which:Fig.1 is a diagram illustrating a conventional method of applying a watermark in a digital image;Fig.2 to depict the Cove in the form of a digital image according to the present invention; andFig.3 is a block diagram of the processor applying a watermark in a digital image corresponding to the present invention.Preferred embodiments of the inventionBelow are described the preferred embodiments of the present invention with reference to the accompanying drawings.Fig.2 represents the sequence of operations of the program, illustrating the main stages corresponding to the present invention, a method of applying a watermark in a digital image. Each of the main image and the image of the signature consists of a set of image elements. Because the values of the image elements correspond to examples of predetermined values of the color vectors of the respective picture elements representing the image element values of the main image can be generalized so that it can be called the aggregate data of the main image. Lower values of image elements for the main image and image signatures will be called the set of data of the main image and the set of image data signatures, respectively.In accordance with the method Nanase is backupnode image data signatures are filled with zeros as values of image elements, through this, making the size of the population of the image data of the signature the same as the size of data sets of the base image (step 202).For example, if n, l and m are independent predetermined positive integers, then it is assumed that the main image consists of n elements. Also, assuming that l represents the number of picture elements of one and the same direction, i.e. either horizontal or vertical, the amount of data in the aggregate data of the main image, i.e. the number of elements of the main image, n is equal to 2

^{l}. Also, when the image of the signature consists of m picture elements, it is assumed that m is equal to 0,25n.Next, the filled data image signatures are in the form of aggregates wave coefficients of the wave functions at the level l (step 204). Aggregate data of the main image are set as sets of scaling factors the scaling functions at level l (step 206).Now, using the algorithm of wavelet transformation, in which the coefficients of the totality of the wave coefficients and the coefficients of the set of scaling factors is converted in the form of sets of scaling factors at one level, above the level l, which belong to these two sets, that is at the level l+1 (step 208). The number of coefficients is equal to 2

^{l+1}. The aggregate wave coefficients and the set of scaling factors that are included in the set of scaling factors, the transformed algorithm wavelet transformation, are also linearly independent.Further, the watermarked image and formulate key from the transformed sets of scaling factors (step 210). Of the 2

^{l+1}coefficients preferably choose 2

^{1}the coefficients and are used as values of the elements of the watermarked image. The remaining coefficients are considered to be key along with the types of wave functions. For example, the coefficients alternately selected on the basis of the alternating arrangement in accordance with a conversion algorithm at step 208, can be used as a watermarked image, and the remaining coefficients can be used as keys.For a better understanding of the present invention corresponding to the present invention a method of applying a watermark over pagrobimu recovery and decomposition for functions scaling and wave.When k is a number between 1 and 2

^{1}, a j is a number representing the level scaling factors scaling functions can be represented by the value ofa wave coefficients of the wave functions can be represented by the value ofas for the steps 202-206.The transformation algorithm on the stage 208 can be represented by the following scheme (1).In the system of Haardecomposes onandfor example, in accordance with a predetermined algorithm decomposition.In the Haar system the above diagram arithmetically represented by the following equations (2) and (3).Using equations (2) and (3), the transformation algorithm can also be represented by the following equations (4) and (5).In accordance with the above conversion algorithm, for example,installed as a watermarked image, aUstawienia signature isthe converted image can also be represented by the value of, watermarked image can be represented by the expressiona key can be represented by the expression.Now you can extract the image signature from the watermarked image using the key, which is obvious to experts in the field of applying watermarks.As described above, in accordance with the method of applying a watermark according to the present invention, the aggregate data of the main image and the combined image data signatures are combined using the algorithm of wavelet transformation in order to satisfy the linear independent ratio between them. Thus, since the image input signature is orthogonal United with him the image perturbation merged image are affected equally and the components of the merged image, and components of the entered image signatures, i.e. two types of orthogonal components. As a result, the degree of distortion introduced in the image signatures and images that share similar drugs applied watermarks according to the present invention, the image signature entered in the associated image are similar to each other from the point of view of availability and stability. In addition, like the occasion when not attached an image of the signature, it is easy to restore the main image.The above-described method of applying a watermark in a digital image can be taken in the method of encoding a digital image.The image encoded by the encoding method of the digital image containing the runtime of the method of applying a watermark in a digital image to merge the data sets of the base image and sets the image data of the signature to a pre-defined way of Association, by which the aggregate data of the main image and the combined image data signatures are combined linearly independent manner, and to form the watermarked image and the key from the combined image decoding method of decoding a digital image to extract image signature from the watermarked image.Next, a method of applying a watermark in a digital image and the encoding qi is rnym computer. Software codes and code segments constituting the program can easily be logically deduced experienced in the art of computer programmers. The program can also be stored on computer-readable recording media. Examples of recording media include magnetic recording media, magneto-optical recording media, and a media recording media.The above-described method of applying a watermark in a digital image can also be implemented as a processor applying a watermark in a digital image. Fig.3 is a block diagram of the processor applying a watermark in a digital image according to the present invention. Considering Fig.3, note that the corresponding present invention, the processor applying a watermark in a digital image includes the node 302 fill the first node 304 installation, the second node 306 installation, the node 308 conversion and node 310 imaging/key. The processor applying a watermark in a digital image constructed on the basis of the method of applying a watermark in a digital image, shown in Fig.2.The processor applying a watermark in the form of a digital whom I between the corresponding data in the data set image signatures so the size of the population of the image data of the signature is equal to the aggregate data of the main image. The first node 304 installs filled with aggregate data image signatures as aggregates wave coefficients of the wave functions. The second node 306 installs the aggregate data of the main image as sets of scaling factors scaling functions. Node 308 conversion converts the aggregate wave coefficients and the set of scaling factors in the form of sets of scaling factors at one level higher than the level, which belong to two groups, in accordance with a predetermined algorithm, wavelet transformation, in which the aggregate wave coefficients and the set of scaling factors are linear independence. Then, the imaging/key node 310 generates the watermarked image and the key from the transformed sets of scaling factors, coming from node 308 conversion.The above processor applying a watermark in a digital Sobranie digital images can also be implemented by means of the decoding device of a digital image. Device (not shown) decoding the digital image includes a decoding device for decoding the image encoded by the encoding method of the digital image containing the runtime of the method of applying a watermark in a digital image to merge the data sets of the base image and sets the image data of the signature to a pre-defined way of Association, by which the aggregate data of the main image and the combined image data signatures are combined linearly independent way, and to form the watermarked image and the key from the merged image. Using the key, the decoding unit extracts the image of the signature of the watermarked image. Removing the image signature from the watermarked image using the key, can understand the specialists in the technique of watermarking. As the image signature is similar to the combined image in the sense of presence and resistance to external factors), based on the characteristics of the method of applying watermarks to be applied to the coding, ascaridoidea the location of the vibratory wave coefficients and sets of scaling factors, specialists in the art it should be clear that changes and modifications without leaving the scope of the nature and scope of the invention defined in the attached claims.As described above, according to the present invention, the image signatures included in the merged image, similarly to the combined image from the point of view of availability and stability.Industrial applicabilityThe application of digital watermarks can be used to ensure protection of copyright materials on the basis of digital formats.

Claims

1. The method of applying a watermark in a digital image, comprising stages: combine the aggregate data of the main image and the combined image data signatures in a predictable fashion with the purpose of combining the aggregates so that they are linearly independent and form a watermarked image and the key from the merged image.2. The method of applying a watermark in a digital image p. 1, additionally containing phase, according to which the extracted image of the signature of the supplied water is Eseniya watermark in a digital image under item 1.4. A method of encoding a digital image containing a method of applying a watermark in a digital image according to p. 2.5. The method of applying a watermark in a digital image, comprising stages of: (a) insert a pre-defined values of image elements between the respective data sets of the image data of the signature so that the aggregate size of the image data of the signature was the same as the size of the population data of the main image, (b) establish the filled data image signatures in the form of aggregates wave coefficients of the wave functions, (c) establish a set of data of the main image in the form of sets of scaling factors scaling functions, and (d) transform the totality of the wave coefficients and the set of scaling factors as sets of scaling factors at one level above the level, which belong to two groups, in accordance with a predetermined algorithm, wavelet transformation, in which the aggregate wave coefficients and the set of scaling factors are linearly Nezavisimoye values of image elements are zeros.7. The method of applying a watermark in a digital image under item 5, in which a pre-defined algorithm wavelet transformation includes a step, in accordance with which in turn have coefficients of vibratory wave coefficients and coefficients of sets of scaling factors.8. The method of applying a watermark in a digital image p. 6, in which a pre-defined algorithm wavelet transformation includes a step according to which in turn have coefficients of vibratory wave coefficients and coefficients of sets of scaling factors.9. The method of applying a watermark in a digital image p. 5, further containing the step (e), according to which form the watermarked image and the key from the transformed sets of scaling factors.10. The method of applying a watermark in a digital image p. 9, further containing the step (f), which extracts the image of the signature of the watermarked image using the key.11. A method of encoding a digital image containing a method of applying a watermark in the form of securities, the values of the image elements are zeros.13. A method of encoding a digital image on p. 11, in which a pre-defined algorithm wavelet transformation includes a step, in accordance with which in turn have coefficients of vibratory wave coefficients and coefficients of sets of scaling factors.14. A method of encoding a digital image on p. 12, in which a pre-defined algorithm wavelet transformation includes a step according to which in turn have coefficients of vibratory wave coefficients and coefficients of sets of scaling factors.15. A method of encoding a digital image on p. 11, further containing the step (e), according to which form the watermarked image and the key from the transformed sets of scaling factors.16. Machine-readable recording medium for storing program codes to perform the method of applying a watermark in a digital image, comprising stages; (a) insert pre-defined values of image elements between the respective data sets of the image data of the signature so that the size of the population data isopropylene aggregate data image signatures in the form of aggregates wave coefficients of the wave functions, (c) establish a set of data of the main image in the form of sets of scaling factors scaling functions, and (d) convert the aggregate wave coefficients and the set of scaling factors as sets of scaling factors at one level above the level, which belong to two groups, in accordance with a predetermined algorithm, wavelet transformation, in which the aggregate wave coefficients and the set of scaling factors are linearly independent.17. Machine-readable recording medium according to p. 16, in which predetermined values of the image elements correspond to the zeros.18. Machine-readable recording medium according to p. 16, in which a pre-defined algorithm wavelet transformation includes a step according to which in turn have coefficients of vibratory wave coefficients and coefficients of sets of scaling factors.19. Machine-readable recording medium on p. 17, in which a pre-defined algorithm wavelet transformation includes a step according to which in turn have ratios is 20. Machine-readable recording medium according to p. 16, further containing the step (e), which form the watermarked image and the key from the transformed sets of scaling factors.21. Machine-readable recording medium according to p. 20, further containing the step (f), according to which the extracted image signature from the watermarked image using the key.22. A method of decoding a digital image for decoding the image encoded by the encoding method of the digital image containing the runtime of the method of applying a watermark in a digital image to merge the data sets of the base image and sets the image data of the signature to a pre-defined way of Association, by which the aggregate data of the main image and the combined image data signatures combined linearly independent manner, and to form the watermarked image and the key from the combined image, and a method of decoding a digital image includes a step according to which the extracted image of the signature of the supplied vodjanye, containing a filling unit for inserting predetermined values of the picture elements between the respective data sets of the image data of the signature so that the aggregate size of the image data of the signature was the same as the size of the population data of the main image, the first node to setup the data sets of image signatures as aggregates wave coefficients of the wave functions, the second node installation to install the data sets of the base image as sets of scaling factors scaling functions, and site conversion for converting vibratory wave coefficients and sets of scaling factors as sets of scaling factors at one level above the level, which owns two together, in accordance with a predetermined algorithm, wavelet transformation, in which the aggregate wave coefficients and the set of scaling factors are linearly independent.24. The processor applying a watermark in a digital image p. 23, in which the pre-defined testing image by p. 23, in which a pre-defined algorithm wavelet transformation includes a step according to which in turn have coefficients of vibratory wave coefficients and coefficients of sets of scaling factors.26. The processor applying a watermark in a digital image according to p. 24, in which a pre-defined algorithm wavelet transformation includes a step according to which in turn have coefficients of vibratory wave coefficients and coefficients of sets of scaling factors.27. The processor applying a watermark in a digital image p. 23, further containing the step (e), according to which produce watermarked image and the key from the transformed set of scaling factors.28. The processor applying a watermark in a digital image according to p. 27, further containing the step (f), which extracts the image of the signature of the watermarked image using the key.29. Device for encoding a digital image that contains the processor applying a watermark in a digital image p. 23.30. The device codiovan is nothing.31. Device for encoding a digital image on p. 29, in which a pre-defined algorithm wavelet transformation includes a step according to which in turn have coefficients of vibratory wave coefficients and coefficients of sets of scaling factors.32. Device for encoding a digital image on p. 30, in which a pre-defined algorithm wavelet transformation includes a step according to which in turn have coefficients of vibratory wave coefficients and coefficients of sets of scaling factors.33. Device for encoding a digital image on p. 29, further containing the step (e), according to which produce watermarked image and the key from the transformed set of scaling factors.34. Device for encoding a digital image on p. 33, further containing the step (f), which extracts the image of the signature of the watermarked image using the key.35. The decoding device of a digital image for decoding the image encoded by the encoding method of digital image containing this what I watermark in a digital image with the purpose of combining data sets of the base image and sets the image data of the signature in a predictable fashion Association, by which the aggregate data of the main image and the combined image data signatures combined linearly independent manner, and to form the watermarked image and the key from the combined image, and the decoding device of a digital image contains a decoding device for extracting image signature from the watermarked image using the key.

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2 cl, 7 dwg

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2 cl, 7 dwg

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