阅读说明：本技术 水印嵌入和水印提取方法、装置及设备 (Watermark embedding method, watermark extracting method, watermark embedding device, watermark extracting device and equipment ) 是由 刘永亮 田冬 陆哲明 于 2018-09-07 设计创作，主要内容包括：本申请公开了一种水印嵌入方法,包括：根据预先设定的至少一个参考图像分辨率,确定第一图像对应的参考图像分辨率；所述第一图像为待嵌入水印信息的图像；根据所述第一图像对应的参考图像分辨率,对第一图像进行缩放处理,得到第二图像；所述第二图像的分辨率与所述第一图像对应的参考图像分辨率相同；将水印信息嵌入到所述第二图像的频率域系数；对所述第二图像的频率域系数进行逆变换处理,得到嵌入水印信息的第二图像；将嵌入水印信息的第二图像进行缩放处理,得到与第一图像分辨率相同的图像。采用上述方法,提高水印的抗缩放攻击能力。(The application discloses a watermark embedding method, which comprises the following steps: determining a reference image resolution corresponding to the first image according to at least one preset reference image resolution; the first image is an image to be embedded with watermark information; according to the resolution of the reference image corresponding to the first image, carrying out scaling processing on the first image to obtain a second image; the resolution of the second image is the same as the resolution of the reference image corresponding to the first image; embedding watermark information into frequency domain coefficients of the second image; carrying out inverse transformation processing on the frequency domain coefficient of the second image to obtain a second image embedded with watermark information; and carrying out scaling processing on the second image embedded with the watermark information to obtain an image with the same resolution as the first image. By adopting the method, the scaling attack resistance of the watermark is improved.)

1. A watermark embedding method, comprising:

determining a reference image resolution corresponding to the first image according to at least one preset reference image resolution; the first image is an image to be embedded with watermark information;

according to the resolution of a reference image corresponding to the first image, carrying out scaling processing on the first image to obtain a second image; the resolution of the second image is the same as the resolution of the reference image corresponding to the first image;

embedding watermark information into frequency domain coefficients of the second image;

carrying out inverse transformation processing on the frequency domain coefficient of the second image to obtain a second image embedded with watermark information;

and carrying out scaling processing on the second image embedded with the watermark information to obtain an image with the same resolution as the first image.

2. The method of claim 1, wherein embedding watermark information into frequency domain coefficients of the second image comprises:

carrying out blocking processing on the second image to obtain an image block of the second image;

transforming the image block of the second image from a space domain to a frequency domain to obtain a frequency domain coefficient of the image block of the second image;

quantizing the frequency domain coefficients of the image blocks of the second image to obtain quantized frequency domain coefficients;

embedding the watermark information into the quantized frequency domain coefficients.

3. The method of claim 2, wherein embedding watermark information into the quantized frequency domain coefficients comprises:

converting the watermark information into a first watermark information image;

converting the first watermark information image into a watermark bit sequence;

embedding the watermark bit sequence in the quantized frequency domain coefficients.

4. The method of claim 3, wherein converting the first watermark information image into a watermark bit sequence comprises:

scrambling the first watermark information image to obtain a second watermark information image; the second watermark information image is the scrambled first watermark information image;

and converting the second watermark information image into a watermark bit sequence.

5. The method according to claim 4, wherein the scrambling the first watermark information image to obtain a second watermark information image comprises:

and scrambling the first watermark information image by using a scrambling code to obtain a second watermark information image.

6. The method of claim 5, further comprising:

and providing the reference image resolution and the scrambling code corresponding to the first image as a key to a watermark information extraction end.

7. The method according to claim 1, wherein the determining the reference picture resolution corresponding to the first picture according to at least one preset reference picture resolution comprises:

and selecting a reference image resolution which is the smallest difference with the resolution of the first image from at least one preset reference image resolution as the reference image resolution corresponding to the first image.

8. The method of claim 1, further comprising:

and providing the reference image resolution corresponding to the first image to a watermark information extraction end.

9. A watermark extraction method, comprising:

obtaining a first image of watermark information to be extracted;

determining a reference image resolution used when embedding watermark information;

scaling the first image to obtain a second image with the resolution same as that of the reference image;

watermark information is extracted from the frequency domain coefficients of the second image.

10. The method of claim 9, wherein determining the reference picture resolution for embedding the watermark information comprises:

determining the resolution of the reference image used when the watermark information is embedded according to the key containing the resolution of the reference image provided by the watermark information embedding end; alternatively, the first and second electrodes may be,

and determining the resolution of the reference image used when the watermark information is embedded according to the resolution of the reference image provided by the watermark information embedding end.

11. The method of claim 9, further comprising:

carrying out blocking processing on the second image to obtain an image block of the second image;

transforming the image block of the second image from a space domain to a frequency domain to obtain a frequency domain coefficient of the image block of the second image;

quantizing the frequency domain coefficients of the image blocks of the second image to obtain quantized frequency domain coefficients;

the extracting of the embedded watermark information from the frequency domain coefficient of the second image includes:

extracting embedded watermark information from the quantized frequency domain coefficients.

12. The method of claim 9, wherein extracting the embedded watermark information from the frequency domain coefficients of the second image comprises:

extracting an embedded watermark bit sequence from the frequency domain coefficients of the second image;

obtaining a first watermark information image according to the watermark bit sequence;

and obtaining the watermark information according to the first watermark information image.

13. The method of claim 12, wherein obtaining a first watermark information image from the watermark bit sequence comprises:

obtaining a second watermark information image according to the watermark bit sequence;

and performing anti-scrambling processing on the second watermark information image to obtain the first watermark information image.

14. The method of claim 13, wherein unscrambling the second watermark information image to obtain the first watermark information image comprises:

and performing anti-scrambling processing on the second watermark information image by using a scrambling code to obtain a first watermark information image.

15. The method of claim 14, further comprising:

obtaining the scrambling code from a key containing the scrambling code provided by a watermark information embedding end; alternatively, the first and second electrodes may be,

the scrambled password is obtained from a pre-agreed key containing the scrambled password.

16. A watermark embedding apparatus, comprising:

the reference image resolution determining unit is used for determining the resolution of a reference image corresponding to the first image according to at least one preset reference image resolution; the first image is an image to be embedded with a watermark;

the second image obtaining unit is used for carrying out scaling processing on the first image according to the resolution of the reference image corresponding to the first image to obtain a second image; the resolution of the second image is the same as the resolution of the reference image corresponding to the first image;

a watermark information embedding unit configured to embed watermark information into a frequency domain coefficient of the second image;

the second image inverse transformation processing unit is used for carrying out inverse transformation processing on the frequency domain coefficient of the second image to obtain the second image embedded with the watermark information;

and the second image scaling processing unit is used for scaling the second image embedded with the watermark information to obtain an image with the same resolution as the first image.

17. An electronic device, comprising:

a processor; and

a memory for storing a program of a watermark embedding method, the apparatus performing the following steps after being powered on and running the program of the watermark embedding method by the processor:

determining a reference image resolution corresponding to the first image according to at least one preset reference image resolution; the first image is an image to be embedded with watermark information;

according to the resolution of a reference image corresponding to the first image, carrying out scaling processing on the first image to obtain a second image; the resolution of the second image is the same as the resolution of the reference image corresponding to the first image;

embedding watermark information into frequency domain coefficients of the second image;

carrying out inverse transformation processing on the frequency domain coefficient of the second image to obtain a second image embedded with watermark information;

and carrying out scaling processing on the second image embedded with the watermark information to obtain an image with the same resolution as the first image.

18. A storage device, characterized in that,

a program storing a watermark embedding method, the program being executed by a processor to perform the steps of:

determining a reference image resolution corresponding to the first image according to at least one preset reference image resolution; the first image is an image to be embedded with watermark information;

according to the resolution of a reference image corresponding to the first image, carrying out scaling processing on the first image to obtain a second image; the resolution of the second image is the same as the resolution of the reference image corresponding to the first image;

embedding watermark information into frequency domain coefficients of the second image;

carrying out inverse transformation processing on the frequency domain coefficient of the second image to obtain a second image embedded with watermark information;

and carrying out scaling processing on the second image embedded with the watermark information to obtain an image with the same resolution as the first image.

19. A watermark extraction apparatus, comprising:

the first image acquisition unit is used for acquiring a first image of watermark information to be extracted;

a reference image resolution determining unit configured to determine a reference image resolution used when watermark information is embedded;

a second image obtaining unit, configured to perform scaling processing on the first image to obtain a second image with a resolution that is the same as the resolution of the reference image;

and the watermark information extraction unit is used for extracting watermark information from the frequency domain coefficient of the second image.

20. An electronic device, comprising:

a processor; and

a memory for storing a program of a watermark extraction method, the apparatus performing the following steps after being powered on and running the program of the watermark extraction method by the processor:

obtaining a first image of watermark information to be extracted;

determining a reference image resolution used when embedding watermark information;

scaling the first image to obtain a second image with the resolution same as that of the reference image;

watermark information is extracted from the frequency domain coefficients of the second image.

21. A storage device, characterized in that,

a program storing a watermark extraction method, the program being executed by a processor to perform the steps of:

obtaining a first image of watermark information to be extracted;

determining a reference image resolution used when embedding watermark information;

scaling the first image to obtain a second image with the resolution same as that of the reference image;

watermark information is extracted from the frequency domain coefficients of the second image.

22. A watermark embedding method, comprising:

acquiring a target resolution and a first image to be embedded with watermark information;

according to the target resolution, performing first scaling processing on the first image to obtain a second image, wherein the resolution of the second image and the target resolution meet a first preset error range;

embedding the watermark information into the second image;

and carrying out second scaling processing on the second image embedded with the watermark information to obtain a third image, wherein the resolution of the third image and the resolution of the first image meet a second preset error range.

23. The method of claim 22, wherein said embedding the watermark into the second image comprises:

embedding the watermark into frequency domain coefficients of the second image;

and carrying out inverse transformation processing on the frequency domain coefficient of the second image to obtain the second image embedded with the watermark information.

24. The method of claim 22, wherein said obtaining a target resolution comprises:

acquiring a resolution sample library;

and retrieving a resolution sample meeting a preset condition with the resolution of the first image from the resolution sample library as a target resolution.

25. The method of claim 22, wherein said obtaining a target resolution comprises:

a target resolution input by a client is received.

26. The method of claim 22, wherein said obtaining a target resolution comprises:

acquiring a target application;

and setting the target resolution according to the resolution corresponding to the target application.

27. The method of claim 22, wherein the first predetermined error range is the same as the second predetermined error range.

Technical Field

The present application relates to digital watermarking technologies, and in particular, to a watermark embedding method and apparatus, an electronic device, and a storage device. The application also relates to a watermark extraction method, a watermark extraction device, electronic equipment and storage equipment.

Background

At present, people can conveniently transmit digital information to all parts of the world by means of electronic equipment such as computers, scanners and the like. But the following side effect is that the data file is transmitted through the network, so that a malicious person can copy and spread the copyrighted content without permission of the owner of the work, and therefore, how to implement effective copyright protection, traceability and information security means in the network environment becomes an urgent practical problem. Watermarking is an effective technical solution to the above problems. The anti-attack characteristic of the watermarking technology is an important measure for the quality of the watermarking technology or whether the watermarking technology can be practically applied.

For digital images, the existing image watermarking technology can basically resist signal noise attack well. However, once the image is subjected to scaling attack, the existing image watermarking technology cannot be effectively applied to a real service scene. The main reason is that the existing image watermarking technology for scaling attack has extremely insufficient embedding capacity or small scaling resistance.

Therefore, in order to ensure the security of the watermark, the scaling attack resistance of the watermark needs to be improved.

Disclosure of Invention

The application provides a watermark embedding method, a watermark embedding device, electronic equipment and storage equipment, so that the scaling attack resistance of the watermark is improved.

The application provides a watermark embedding method, which comprises the following steps:

determining a reference image resolution corresponding to the first image according to at least one preset reference image resolution; the first image is an image to be embedded with watermark information;

according to the resolution of a reference image corresponding to the first image, carrying out scaling processing on the first image to obtain a second image; the resolution of the second image is the same as the resolution of the reference image corresponding to the first image;

embedding watermark information into frequency domain coefficients of the second image;

carrying out inverse transformation processing on the frequency domain coefficient of the second image to obtain a second image embedded with watermark information;

and carrying out scaling processing on the second image embedded with the watermark information to obtain an image with the same resolution as the first image.

Optionally, the embedding the watermark information into the frequency domain coefficient of the second image includes:

carrying out blocking processing on the second image to obtain an image block of the second image;

transforming the image block of the second image from a space domain to a frequency domain to obtain a frequency domain coefficient of the image block of the second image;

quantizing the frequency domain coefficients of the image blocks of the second image to obtain quantized frequency domain coefficients;

embedding the watermark information into the quantized frequency domain coefficients.

Optionally, the embedding the watermark information into the quantized frequency domain coefficients includes:

converting the watermark information into a first watermark information image;

converting the first watermark information image into a watermark bit sequence;

embedding the watermark bit sequence in the quantized frequency domain coefficients.

Optionally, the converting the first watermark information image into a watermark bit sequence includes:

scrambling the first watermark information image to obtain a second watermark information image; the second watermark information image is the scrambled first watermark information image;

and converting the second watermark information image into a watermark bit sequence.

Optionally, the scrambling the first watermark information image to obtain a second watermark information image includes:

and scrambling the first watermark information image by using a scrambling code to obtain a second watermark information image.

Optionally, the method further includes:

and providing the reference image resolution and the scrambling code corresponding to the first image as a key to a watermark information extraction end.

Optionally, the determining, according to at least one preset reference image resolution, a reference image resolution corresponding to the first image includes:

and selecting a reference image resolution which is the smallest difference with the resolution of the first image from at least one preset reference image resolution as the reference image resolution corresponding to the first image.

Optionally, the method further includes:

and providing the reference image resolution corresponding to the first image to a watermark information extraction end.

The application also provides a watermark extraction method, which comprises the following steps:

obtaining a first image of watermark information to be extracted;

determining a reference image resolution used when embedding watermark information;

scaling the first image to obtain a second image with the resolution same as that of the reference image;

watermark information is extracted from the frequency domain coefficients of the second image.

Optionally, the determining a resolution of a reference image used when embedding the watermark information includes:

determining the resolution of the reference image used when the watermark information is embedded according to the key containing the resolution of the reference image provided by the watermark information embedding end; alternatively, the first and second electrodes may be,

and determining the resolution of the reference image used when the watermark information is embedded according to the resolution of the reference image provided by the watermark information embedding end.

Optionally, the method further includes:

carrying out blocking processing on the second image to obtain an image block of the second image;

transforming the image block of the second image from a space domain to a frequency domain to obtain a frequency domain coefficient of the image block of the second image;

quantizing the frequency domain coefficients of the image blocks of the second image to obtain quantized frequency domain coefficients;

the extracting of the embedded watermark information from the frequency domain coefficient of the second image includes:

extracting embedded watermark information from the quantized frequency domain coefficients.

Optionally, the extracting the embedded watermark information from the frequency domain coefficient of the second image includes:

extracting an embedded watermark bit sequence from the frequency domain coefficients of the second image;

obtaining a first watermark information image according to the watermark bit sequence;

and obtaining the watermark information according to the first watermark information image.

Optionally, the obtaining a first watermark information image according to the watermark bit sequence includes:

obtaining a second watermark information image according to the watermark bit sequence;

and performing anti-scrambling processing on the second watermark information image to obtain the first watermark information image.

Optionally, the performing descrambling processing on the second watermark information image to obtain a first watermark information image includes:

and performing anti-scrambling processing on the second watermark information image by using a scrambling code to obtain a first watermark information image.

Optionally, the method further includes:

obtaining the scrambling code from a key containing the scrambling code provided by a watermark information embedding end; alternatively, the first and second electrodes may be,

the scrambled password is obtained from a pre-agreed key containing the scrambled password.

The present application further provides a watermark embedding apparatus, comprising:

the reference image resolution determining unit is used for determining the resolution of a reference image corresponding to the first image according to at least one preset reference image resolution; the first image is an image to be embedded with a watermark;

the second image obtaining unit is used for carrying out scaling processing on the first image according to the resolution of the reference image corresponding to the first image to obtain a second image; the resolution of the second image is the same as the resolution of the reference image corresponding to the first image;

a watermark information embedding unit configured to embed watermark information into a frequency domain coefficient of the second image;

the second image inverse transformation processing unit is used for carrying out inverse transformation processing on the frequency domain coefficient of the second image to obtain the second image embedded with the watermark information;

and the second image scaling processing unit is used for scaling the second image embedded with the watermark information to obtain an image with the same resolution as the first image.

The present application additionally provides an electronic device comprising:

a processor; and

a memory for storing a program of a watermark embedding method, the apparatus performing the following steps after being powered on and running the program of the watermark embedding method by the processor:

determining a reference image resolution corresponding to the first image according to at least one preset reference image resolution; the first image is an image to be embedded with watermark information;

according to the resolution of a reference image corresponding to the first image, carrying out scaling processing on the first image to obtain a second image; the resolution of the second image is the same as the resolution of the reference image corresponding to the first image;

embedding watermark information into frequency domain coefficients of the second image;

carrying out inverse transformation processing on the frequency domain coefficient of the second image to obtain a second image embedded with watermark information;

and carrying out scaling processing on the second image embedded with the watermark information to obtain an image with the same resolution as the first image.

The present application further provides a storage device,

a program storing a watermark extraction method, the program being executed by a processor to perform the steps of:

determining a reference image resolution corresponding to the first image according to at least one preset reference image resolution; the first image is an image to be embedded with watermark information;

according to the resolution of a reference image corresponding to the first image, carrying out scaling processing on the first image to obtain a second image; the resolution of the second image is the same as the resolution of the reference image corresponding to the first image;

embedding watermark information into frequency domain coefficients of the second image;

carrying out inverse transformation processing on the frequency domain coefficient of the second image to obtain a second image embedded with watermark information;

and carrying out scaling processing on the second image embedded with the watermark information to obtain an image with the same resolution as the first image.

The present application further provides a watermark extraction apparatus, including:

the first image acquisition unit is used for acquiring a first image of watermark information to be extracted;

a reference image resolution determining unit configured to determine a reference image resolution used when watermark information is embedded;

a second image obtaining unit, configured to perform scaling processing on the first image to obtain a second image with a resolution that is the same as the resolution of the reference image;

and the watermark information extraction unit is used for extracting watermark information from the frequency domain coefficient of the second image.

The present application additionally provides an electronic device comprising:

a processor; and

a memory for storing a program of a watermark extraction method, the apparatus performing the following steps after being powered on and running the program of the watermark extraction method by the processor:

obtaining a first image of watermark information to be extracted;

determining a reference image resolution used when embedding watermark information;

scaling the first image to obtain a second image with the resolution same as that of the reference image;

watermark information is extracted from the frequency domain coefficients of the second image.

The present application also provides a storage device that,

a program storing a watermark extraction method, the program being executed by a processor to perform the steps of:

obtaining a first image of watermark information to be extracted;

determining a reference image resolution used when embedding watermark information;

scaling the first image to obtain a second image with the resolution same as that of the reference image;

watermark information is extracted from the frequency domain coefficients of the second image.

The application also provides a watermark embedding method, which comprises the following steps:

acquiring a target resolution and a first image to be embedded with watermark information;

according to the target resolution, performing first scaling processing on the first image to obtain a second image, wherein the resolution of the second image and the target resolution meet a first preset error range;

embedding the watermark information into the second image;

and carrying out second scaling processing on the second image embedded with the watermark information to obtain a third image, wherein the resolution of the third image and the resolution of the first image meet a second preset error range.

Optionally, embedding the watermark into the second image includes:

embedding the watermark into frequency domain coefficients of the second image;

and carrying out inverse transformation processing on the frequency domain coefficient of the second image to obtain the second image embedded with the watermark information.

Optionally, obtaining the target resolution includes:

acquiring a resolution sample library;

and retrieving a resolution sample meeting a preset condition with the resolution of the first image from the resolution sample library as a target resolution.

Optionally, obtaining the target resolution includes:

a target resolution input by a client is received.

Optionally, obtaining the target resolution includes:

acquiring a target application;

and setting the target resolution according to the resolution corresponding to the target application.

Optionally, the first preset error range is the same as the second preset error range.

Compared with the prior art, the method has the following advantages:

the application provides a watermark embedding method, a watermark embedding device, electronic equipment and storage equipment, wherein a first image is converted into a second image with the resolution identical to that of a corresponding reference image, and watermark information is embedded into the frequency domain of the second image.

Drawings

Fig. 1 is a flowchart of a watermark embedding method according to a first embodiment of the present application.

Fig. 2 is a schematic diagram of a first watermark information image provided in the first embodiment of the present application.

Fig. 3 is a flowchart of a watermark extraction method according to a second embodiment of the present application.

Fig. 4 is a schematic diagram of a watermark embedding apparatus according to a third embodiment of the present application.

Fig. 5 is a schematic diagram of an electronic device according to a fourth embodiment of the present application.

Fig. 6 is a schematic diagram of a watermark extraction apparatus according to a sixth embodiment of the present application.

Fig. 7 is a schematic diagram of an electronic device according to a seventh embodiment of the present application.

Fig. 8 is a flowchart of a watermark embedding method according to a ninth embodiment of the present application.

Fig. 9 is a schematic diagram of a scene of watermark embedding according to a ninth embodiment of the present application.

Fig. 10 is a schematic view of a scene of watermark extraction according to a ninth embodiment of the present application.

Detailed Description

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. This application is capable of implementation in many different ways than those herein set forth and of similar import by those skilled in the art without departing from the spirit of this application and is therefore not limited to the specific implementations disclosed below.

A first embodiment of the present application provides a watermark embedding method, which is described below with reference to fig. 1 and 2.

As shown in fig. 1, in step S101, a reference image resolution corresponding to a first image is determined according to at least one preset reference image resolution; the first image is an image to be embedded with watermark information.

The watermark information refers to identification information to be embedded into the first image. The watermark information can be hidden and embedded into the first image, the use value of the original first image cannot be influenced, and the watermark information cannot be easily detected and modified again. But the watermark information can be identified and recognized by the producer. The watermark information embedded in the first image can achieve the purposes of confirming content creators and purchasers, transmitting secret information, judging whether the first image is tampered or not, and the like. The watermark information may be a company name of a certain company, or may be an employee number or other identification information of a certain employee.

The reference image resolution refers to the image resolution which needs to be referred to when the first image is converted into the second image; a plurality of reference image resolutions may be set in advance, for example, 4 reference image resolutions may be set, which are: 128*128,256*256,512*512,1024*1024. The resolution of the reference image is defined without any special requirement, for example, 125 × 124, 125 × 100.

It should be noted that, the more kinds of reference image resolutions are set, the less distortion may be caused by scaling. For example: if the reference image resolution is only 128 × 128 or 256 × 256, if the first image resolution is 800 × 800, only the reference image resolution of 256 × 256 may be selected, and if the reference image resolution includes 128 × 128,256 × 256 or 600 × 600, then the reference image resolution of 600 × 600 may be selected, where the distortion caused by scaling is smaller than the distortion caused by selecting the reference image resolution of 256 × 256.

The reference image resolution corresponding to the first image refers to a reference image resolution selected from a plurality of reference image resolutions, and is used for performing scaling processing on the first image to obtain a second image. For example, 256 × 256 may be selected as the reference image resolution corresponding to the first image.

Specifically, when determining the resolution of the reference image corresponding to the first image, in order to make the difference between the resolutions of the second image and the first image smaller, the resolution of the reference image which is the smallest difference from the resolution of the first image may be selected from at least one preset resolution of the reference images as the resolution of the reference image corresponding to the first image. For example, if the first image resolution is 200 × 300, 256 × 256 may be selected from the above 4 reference image resolutions as the reference image resolution corresponding to the first image.

In order that the watermark information extraction end can obtain the reference image resolution corresponding to the first image, the reference image resolution corresponding to the first image can be provided for the watermark information extraction end. The reference image resolution corresponding to the first image is provided to the watermark information extraction end, and two ways can be adopted: one way is that: sending the reference image resolution corresponding to the first image to a watermark extraction end in a form of a single message; the other mode is as follows: and providing the reference image resolution corresponding to the first image to the watermark information extraction end in a mode predetermined by the watermark information extraction end and the watermark information embedding end.

As shown in fig. 1, in step S102, a scaling process is performed on a first image according to a reference image resolution corresponding to the first image to obtain a second image; the resolution of the second image is the same as the resolution of the reference image corresponding to the first image.

And carrying out scaling processing on the first image according to the resolution of the reference image corresponding to the first image to obtain a second image with the same resolution as the reference image corresponding to the first image. Still using the above example, the first image is scaled according to the reference image resolution 256 × 256 corresponding to the first image, so as to obtain the second image, where the resolution of the second image is 256 × 256.

As shown in fig. 1, in step S103, watermark information is embedded into frequency domain coefficients of the second image.

The frequency domain comprising: DCT domain, DWT domain, DFT domain, etc.

Embedding watermark information into frequency domain coefficients of said second image, comprising the steps of:

carrying out blocking processing on the second image to obtain an image block of the second image;

transforming the image block of the second image from a space domain to a frequency domain to obtain a frequency domain coefficient of the image block of the second image;

quantizing the frequency domain coefficients of the image blocks of the second image to obtain quantized frequency domain coefficients;

embedding the watermark information into the quantized frequency domain coefficients.

And performing block processing on the second image to obtain image blocks of the second image, wherein the resolution of the image blocks of the second image can be 16 × 16, 8 × 8 and the like. When the resolution of the image block is greater than 8 × 8, the transform efficiency from the spatial domain to the frequency domain of the image block is not increased much, but the complexity is increased greatly, so it is preferable to perform the blocking processing on the second image to obtain the image block with the resolution of 8 × 8 of the second image, and calculate the frequency domain coefficient for each image block with the resolution of 8 × 8. The process of embedding the watermark information into the frequency domain coefficients of the image block with the resolution of 8 × 8 of the second image is as follows: firstly, two-dimensional data of each image block with the resolution of 8 × 8 is converted into a frequency domain from a space domain to obtain 8 × 8 frequency domain coefficients, then the frequency domain coefficients of each image block of a second image are quantized to obtain quantized frequency domain coefficients, and finally watermark information is embedded into the quantized frequency domain coefficients.

Said embedding watermark information into said quantized frequency domain coefficients comprises:

converting the watermark information into a first watermark information image; converting the image into a first watermark information image;

converting the first watermark information image into a watermark bit sequence;

embedding the watermark bit sequence in the quantized frequency domain coefficients.

When embedding the watermark information into the quantized frequency domain coefficients, the watermark information may be first converted into a first watermark information image; then converting the first watermark information image into a watermark bit sequence; finally, the watermark bit sequence is embedded into the quantized frequency domain coefficients. Wherein, the bit sequence may refer to a 0, 1 sequence in binary representation. As shown in fig. 2, it is a first watermark information image into which the character string watermark information "123" is converted. The watermark information is converted into a first watermark information image, so that the robustness can be improved, for example, a character with the work number of 12345678 is embedded, if the character is firstly converted into 0/1-bit sequence information, 64 bits in total of 8 x 8 are embedded for ASCAII, and a character extraction error can be caused if the information extraction of one bit is wrong; if 12345678 is converted into an image, for example, the resolution of the image is 80 × 20, and 1600 bits are used, the amount of information embedded when watermark information is embedded in the form of a picture is significantly increased, and thus robustness is improved.

Further, in order to improve the security of watermark embedding, after the watermark information is converted into the first watermark information image; scrambling processing can be performed on the first watermark information image to obtain a second watermark information image; the second watermark information image is the scrambled first watermark information image; and converting the second watermark information image into a watermark bit sequence and embedding the watermark bit sequence into the quantized frequency domain coefficients.

When the first watermark information image is scrambled to obtain the second watermark information image, the scrambling code can be used for assisting in scrambling the first watermark information image to obtain the second watermark information image.

Further, if the scrambling code is used, the reference image resolution and the scrambling code corresponding to the first image can be provided to the watermark information extraction end as a key, so that the watermark information extraction end can accurately obtain the reference image resolution used when the first image is converted into the second image and the adopted scrambling code when extracting the watermark information. And providing the reference image resolution and the scrambling code corresponding to the first image as a key to a watermark information extraction end, wherein two modes can be adopted: one way is that: sending the key to a watermark information extraction end in a form of a single message; the other mode is as follows: and determining the key in a mode predetermined by the watermark information extraction end and the watermark information embedding end.

The watermark information is embedded into the frequency domain coefficient of the second image through the step.

As shown in fig. 1, in step S104, the frequency domain coefficients of the second image are subjected to inverse transform processing, so as to obtain a second image with embedded watermark information.

After embedding the watermark information into the frequency domain coefficients of the second image, it is necessary to perform inverse transform processing on the frequency domain coefficients of the second image to convert the second image from the frequency domain into the spatial domain, where the second image is the second image with the watermark information embedded therein.

As shown in fig. 1, in step S105, the second image with the embedded watermark information is subjected to scaling processing, so as to obtain an image with the same resolution as the first image.

This step is the reverse of step S102, and step S102 performs scaling processing on the first image to generate the second image, and after embedding the watermark information in the second image, it is necessary to perform scaling processing on the second image in the reverse direction, that is, if the first image is subjected to scaling processing in step S102, this step performs scaling processing on the second image, and if the first image is subjected to scaling processing in step S102, this step performs scaling processing on the second image. Still using the example of step S102, the second image with the embedded watermark information is scaled to obtain an image with the same resolution as the first image, that is, the second image with the embedded watermark information with a resolution of 256 × 256 is scaled to obtain an image with a resolution of 200 × 300.

Now, a detailed description is given of an implementation of the watermark embedding method provided in the first embodiment of the present application. In the first embodiment of the application, a first image is converted into a second image with the resolution same as that of a corresponding reference image, watermark information is embedded into a frequency domain of the second image, the second image with the embedded watermark information is converted into a spatial domain from the frequency domain, and the resolution of the second image with the embedded watermark information is converted into the resolution of the first image to obtain an image with the resolution same as that of the first image; compared with the first image, although a large part of pixel values of the obtained image with the same resolution as the first image are changed, the frequency domain coefficient is not changed too much, so that watermark information can be extracted correctly even if the image is subjected to scaling attack, and the scaling attack resistance of the watermark is improved. In addition, the first embodiment of the application also has the advantages of large capacity of embedding watermark information and strong robustness. For example, the resolution of the reference image corresponding to the first image is 512 × 512, the second image is divided into 8 × 8 image blocks, the two-dimensional data of each image block with the resolution of 8 × 8 is transformed from the spatial domain to the frequency domain by using DCT transform, and 512 × 64 × 8bit information, that is, 32768bit information can be embedded by taking the example that 8 bits of intermediate frequency coefficients are embedded in each image block. As can be seen, the first embodiment of the application ensures that the capacity of the embedded watermark information is large and the robustness is extremely strong; meanwhile, the scaling attack resistance is strong, 70% JPEG compression can be resisted, and 3-4 times of amplification attack and 2-3 times of reduction attack can be resisted.

A second embodiment of the present application provides a watermark extraction method, which is described below with reference to fig. 3.

As shown in fig. 3, in step S301, a first image from which watermark information is to be extracted is obtained.

The first image from which the watermark information is to be extracted refers to an image in which the watermark information is embedded by the watermark embedding method provided in the first embodiment of the present application. The first image of the watermark information to be extracted may be an original image embedded with the watermark, or may be a screenshot of the original image embedded with the watermark, for example, an interface is formed by performing layout design and adding images and characters in a small white background image (for example, with a resolution of 100 × 480) embedded with the watermark information, and the screenshot may be the first image of the watermark information to be extracted when a user captures the interface at a mobile phone terminal. Due to the fact that the resolutions of mobile phones of users are different, zooming attack is conducted on the interface during screenshot, and watermarks in the screenshot can be successfully extracted.

As shown in fig. 3, in step S302, the reference image resolution used when embedding watermark information is determined.

The determining of the resolution of the reference image used when embedding the watermark information includes:

determining the resolution of the reference image used when the watermark information is embedded according to the key containing the resolution of the reference image provided by the watermark information embedding end; alternatively, the first and second electrodes may be,

and determining the resolution of the reference image used when the watermark information is embedded according to the resolution of the reference image provided by the watermark information embedding end.

If the watermark information embedding end provides the key containing the resolution of the reference image to the watermark information extracting end, the resolution of the reference image used when the watermark information is embedded can be obtained from the key; if the watermark information embedding terminal provides the reference image resolution to the watermark information extracting terminal, the provided reference image resolution is the reference image resolution used when the watermark information is embedded.

As shown in fig. 3, in step S303, the first image is scaled to obtain a second image having the same resolution as the reference image.

The step ensures that the watermark information embedding and the watermark information extraction are carried out at the same reference image resolution, thereby recovering the synchronous information.

The synchronization information means that for a given watermark algorithm, the watermark extraction end must obtain the exact location where the watermark is embedded, which is also referred to as synchronization information. So that the correct embedded information can be presented at a specific location accordingly. If the position information of the embedded watermark information is lost, the embedded watermark information cannot be correctly extracted even if the embedded watermark information is still in the image, which is called loss of synchronization information.

As shown in fig. 3, in step S304, watermark information is extracted from the frequency domain coefficients of the second image.

If the image is subjected to blocking processing when the watermark information is embedded, the second image also needs to be subjected to blocking processing when the watermark information is extracted, so that an image block of the second image is obtained; then, the image blocks of the second image are transformed from a space domain to a frequency domain to obtain frequency domain coefficients of the image blocks of the second image; and then, carrying out quantization processing on the frequency domain coefficients of the image blocks of the second image to obtain quantized frequency domain coefficients. The extracting of the embedded watermark information from the frequency domain coefficient of the second image includes: extracting embedded watermark information from the quantized frequency domain coefficients.

The extracting of the embedded watermark information from the frequency domain coefficient of the second image includes:

extracting an embedded watermark bit sequence from the frequency domain coefficients of the second image;

obtaining a first watermark information image according to the watermark bit sequence;

and obtaining the watermark information according to the first watermark information image.

If the watermark information image is scrambled when the watermark information is embedded, the obtaining of the first watermark information image according to the watermark bit sequence includes:

obtaining a second watermark information image according to the watermark bit sequence;

and performing anti-scrambling processing on the second watermark information image to obtain the first watermark information image.

Performing anti-scrambling processing on the second watermark information image to obtain a first watermark information image, including:

if the scrambling code is used during watermark information embedding, the scrambling code is required to be used to perform the anti-scrambling processing on the second watermark information image during watermark information extraction, so as to obtain the first watermark information image before scrambling.

The scrambling code can be obtained from a key containing the scrambling code provided by the watermark information embedding end; or from a pre-agreed key containing the scrambled password.

Now, a detailed description is given of an implementation of the watermark extraction method provided in the second embodiment of the present application. The watermark extraction method provided by the second embodiment of the application ensures that watermark information embedding and watermark information extraction are performed at the same reference image resolution, so that no matter what kind of scaling attack is performed on the image embedded with the watermark information, the extraction of the watermark information cannot be influenced, and the embedded watermark information can still be correctly extracted when the image embedded with the watermark information is subjected to the scaling attack.

Corresponding to the above-mentioned watermark embedding method, a third embodiment of the present application further provides a watermark embedding apparatus.

As shown in fig. 4, the watermark embedding apparatus includes:

a reference image resolution determining unit 401, configured to determine, according to at least one preset reference image resolution, a reference image resolution corresponding to the first image; the first image is an image to be embedded with a watermark;

a second image obtaining unit 402, configured to perform scaling processing on the first image according to a reference image resolution corresponding to the first image to obtain a second image; the resolution of the second image is the same as the resolution of the reference image corresponding to the first image;

a watermark information embedding unit 403 for embedding watermark information into frequency domain coefficients of the second image;

a second image inverse transformation processing unit 404, configured to perform inverse transformation processing on the frequency domain coefficient of the second image to obtain a second image embedded with watermark information;

a second image scaling unit 405, configured to scale the second image with the embedded watermark information to obtain an image with the same resolution as the first image.

Optionally, the watermark information embedding unit is specifically configured to:

carrying out blocking processing on the second image to obtain an image block of the second image;

transforming the image block of the second image from a space domain to a frequency domain to obtain a frequency domain coefficient of the image block of the second image;

quantizing the frequency domain coefficients of the image blocks of the second image to obtain quantized frequency domain coefficients;

embedding the watermark information into the quantized frequency domain coefficients.

Optionally, the embedding the watermark information into the quantized frequency domain coefficients includes:

the first watermark information image conversion subunit is used for converting the watermark information into a first watermark information image;

a watermark bit sequence conversion unit, configured to convert the first watermark information image into a watermark bit sequence;

a bit sequence embedding subunit for embedding the watermark bit sequence into the quantized frequency domain coefficients.

Optionally, the watermark bit sequence transformation subunit is specifically configured to:

scrambling the first watermark information image to obtain a second watermark information image; the second watermark information image is the scrambled first watermark information image;

and converting the second watermark information image into a watermark bit sequence.

Optionally, the scrambling the first watermark information image to obtain a second watermark information image includes:

and scrambling the first watermark information image by using a scrambling code to obtain a second watermark information image.

Optionally, the apparatus further comprises:

and the key providing unit is used for providing the reference image resolution and the scrambled password corresponding to the first image as keys to a watermark information extraction end.

Optionally, the determining, according to at least one preset reference image resolution, a reference image resolution corresponding to the first image includes:

and selecting a reference image resolution which is the smallest difference with the resolution of the first image from at least one preset reference image resolution as the reference image resolution corresponding to the first image.

Optionally, the apparatus further comprises:

and the reference image resolution providing unit is used for providing the reference image resolution corresponding to the first image to the watermark information extraction end.

It should be noted that, for the detailed description of the watermark embedding apparatus provided in the third embodiment of the present application, reference may be made to the related description of the first embodiment of the present application, and details are not described here again.

Corresponding to the watermark embedding method provided above, a fourth embodiment of the present application further provides an electronic device.

As shown in fig. 5, the electronic apparatus includes:

a processor 501; and

a memory 502 for storing a program of a watermark embedding method, the apparatus being powered on and executing the program of the watermark embedding method by the processor, and performing the steps of:

determining a reference image resolution corresponding to the first image according to at least one preset reference image resolution; the first image is an image to be embedded with watermark information;

according to the resolution of a reference image corresponding to the first image, carrying out scaling processing on the first image to obtain a second image; the resolution of the second image is the same as the resolution of the reference image corresponding to the first image;

embedding watermark information into frequency domain coefficients of the second image;

carrying out inverse transformation processing on the frequency domain coefficient of the second image to obtain a second image embedded with watermark information;

and carrying out scaling processing on the second image embedded with the watermark information to obtain an image with the same resolution as the first image.

Optionally, the embedding the watermark information into the frequency domain coefficient of the second image includes:

carrying out blocking processing on the second image to obtain an image block of the second image;

transforming the image block of the second image from a space domain to a frequency domain to obtain a frequency domain coefficient of the image block of the second image;

quantizing the frequency domain coefficients of the image blocks of the second image to obtain quantized frequency domain coefficients;

embedding the watermark information into the quantized frequency domain coefficients.

Optionally, the embedding the watermark information into the quantized frequency domain coefficients includes:

converting the watermark information into a first watermark information image;

converting the first watermark information image into a watermark bit sequence;

embedding the watermark bit sequence in the quantized frequency domain coefficients.

Optionally, the converting the first watermark information image into a watermark bit sequence includes:

scrambling the first watermark information image to obtain a second watermark information image; the second watermark information image is the scrambled first watermark information image;

and converting the second watermark information image into a watermark bit sequence.

Optionally, the scrambling the first watermark information image to obtain a second watermark information image includes:

and scrambling the first watermark information image by using a scrambling code to obtain a second watermark information image.

Optionally, the electronic device further performs the following steps:

and providing the reference image resolution and the scrambling code corresponding to the first image as a key to a watermark information extraction end.

Optionally, the determining, according to at least one preset reference image resolution, a reference image resolution corresponding to the first image includes:

and selecting a reference image resolution which is the smallest difference with the resolution of the first image from at least one preset reference image resolution as the reference image resolution corresponding to the first image.

Optionally, the electronic device further performs the following steps:

and providing the reference image resolution corresponding to the first image to a watermark information extraction end.

It should be noted that, for the detailed description of the electronic device provided in the fourth embodiment of the present application, reference may be made to the related description of the first embodiment of the present application, and details are not repeated here.

In accordance with the foregoing watermark embedding method, a fifth embodiment of the present application further provides a storage device storing a program of the watermark embedding method, where the program is executed by a processor to perform the following steps:

determining a reference image resolution corresponding to the first image according to at least one preset reference image resolution; the first image is an image to be embedded with watermark information;

according to the resolution of a reference image corresponding to the first image, carrying out scaling processing on the first image to obtain a second image; the resolution of the second image is the same as the resolution of the reference image corresponding to the first image;

embedding watermark information into frequency domain coefficients of the second image;

carrying out inverse transformation processing on the frequency domain coefficient of the second image to obtain a second image embedded with watermark information;

and carrying out scaling processing on the second image embedded with the watermark information to obtain an image with the same resolution as the first image.

It should be noted that, for the detailed description of the storage device provided in the fifth embodiment of the present application, reference may be made to the related description of the first embodiment of the present application, and details are not described here again.

Corresponding to the above-mentioned watermark extraction method, a sixth embodiment of the present application further provides a watermark extraction apparatus.

As shown in fig. 6, the watermark extraction apparatus includes:

a first image obtaining unit 601, configured to obtain a first image from which watermark information is to be extracted;

a reference image resolution determination unit 602 for determining a reference image resolution used when watermark information is embedded;

a second image obtaining unit 603, configured to perform scaling processing on the first image to obtain a second image with a resolution that is the same as the resolution of the reference image;

a watermark information extraction unit 604, configured to extract watermark information from the frequency domain coefficients of the second image.

Optionally, the reference image resolution determining unit is specifically configured to:

determining the resolution of the reference image used when the watermark information is embedded according to the key containing the resolution of the reference image provided by the watermark information embedding end; alternatively, the first and second electrodes may be,

and determining the resolution of the reference image used when the watermark information is embedded according to the resolution of the reference image provided by the watermark information embedding end.

Optionally, the apparatus further comprises:

the image block obtaining unit is used for carrying out blocking processing on the second image to obtain an image block of the second image;

a frequency domain coefficient obtaining unit, configured to perform spatial domain-to-frequency domain transformation on the image block of the second image to obtain a frequency domain coefficient of the image block of the second image;

a quantized frequency domain coefficient obtaining unit, configured to perform quantization processing on the frequency domain coefficients of the image blocks of the second image to obtain quantized frequency domain coefficients;

the watermark information extraction unit is specifically configured to:

extracting embedded watermark information from the quantized frequency domain coefficients.

Optionally, the watermark information extracting unit includes:

a watermark bit sequence extraction subunit, configured to extract an embedded watermark bit sequence from the frequency domain coefficients of the second image;

a first watermark information image obtaining subunit, configured to obtain a first watermark information image according to the watermark bit sequence;

and the watermark information obtaining subunit is used for obtaining the watermark information according to the first watermark information image.

Optionally, the watermark information obtaining subunit is specifically configured to:

obtaining a second watermark information image according to the watermark bit sequence;

and performing anti-scrambling processing on the second watermark information image to obtain the first watermark information image.

Optionally, the performing descrambling processing on the second watermark information image to obtain a first watermark information image includes:

and performing anti-scrambling processing on the second watermark information image by using a scrambling code to obtain a first watermark information image.

Optionally, the apparatus further comprises:

a scrambled password obtaining unit configured to obtain a scrambled password from a key including the scrambled password provided from a watermark information embedding terminal; alternatively, the scrambled password is obtained from a pre-agreed key containing the scrambled password.

It should be noted that, for the detailed description of the watermark extraction apparatus provided in the sixth embodiment of the present application, reference may be made to the related description of the second embodiment of the present application, and details are not described here again.

A seventh embodiment of the present application further provides an electronic device corresponding to the above-mentioned watermark extraction method.

As shown in fig. 7, the electronic apparatus includes:

a processor 701; and

a memory 702 for storing a program of a watermark extraction method, the apparatus being powered on and executing the program of the watermark extraction method by the processor, and performing the following steps:

obtaining a first image of watermark information to be extracted;

determining a reference image resolution used when embedding watermark information;

scaling the first image to obtain a second image with the resolution same as that of the reference image;

watermark information is extracted from the frequency domain coefficients of the second image.

Optionally, the determining a resolution of a reference image used when embedding the watermark information includes:

determining the resolution of the reference image used when the watermark information is embedded according to the key containing the resolution of the reference image provided by the watermark information embedding end; alternatively, the first and second electrodes may be,

and determining the resolution of the reference image used when the watermark information is embedded according to the resolution of the reference image provided by the watermark information embedding end.

Optionally, the electronic device further performs the following steps:

carrying out blocking processing on the second image to obtain an image block of the second image;

transforming the image block of the second image from a space domain to a frequency domain to obtain a frequency domain coefficient of the image block of the second image;

quantizing the frequency domain coefficients of the image blocks of the second image to obtain quantized frequency domain coefficients;

the extracting of the embedded watermark information from the frequency domain coefficient of the second image includes:

extracting embedded watermark information from the quantized frequency domain coefficients.

Optionally, the extracting the embedded watermark information from the frequency domain coefficient of the second image includes:

extracting an embedded watermark bit sequence from the frequency domain coefficients of the second image;

obtaining a first watermark information image according to the watermark bit sequence;

and obtaining the watermark information according to the first watermark information image.

Optionally, the obtaining a first watermark information image according to the watermark bit sequence includes:

obtaining a second watermark information image according to the watermark bit sequence;

and performing anti-scrambling processing on the second watermark information image to obtain the first watermark information image.

Optionally, the performing descrambling processing on the second watermark information image to obtain a first watermark information image includes:

and performing anti-scrambling processing on the second watermark information image by using a scrambling code to obtain a first watermark information image.

Optionally, the electronic device further performs the following steps:

obtaining the scrambling code from a key containing the scrambling code provided by a watermark information embedding end; alternatively, the first and second electrodes may be,

the scrambled password is obtained from a pre-agreed key containing the scrambled password.

It should be noted that, for the detailed description of the electronic device provided in the seventh embodiment of the present application, reference may be made to the related description of the second embodiment of the present application, and details are not described here again.

Corresponding to the above-mentioned watermark extraction method, an eighth embodiment of the present application further provides a storage device, in which a program of the watermark extraction method is stored, where the program is executed by a processor to perform the following steps:

obtaining a first image of watermark information to be extracted;

determining a reference image resolution used when embedding watermark information;

scaling the first image to obtain a second image with the resolution same as that of the reference image;

watermark information is extracted from the frequency domain coefficients of the second image.

It should be noted that, for the detailed description of the storage device provided in the eighth embodiment of the present application, reference may be made to the related description of the second embodiment of the present application, and details are not described here again.

A ninth embodiment of the present application provides a watermark embedding method, which is described below with reference to fig. 8.

As shown in fig. 8, in step 801, a target resolution and a first image in which watermark information is to be embedded are acquired.

The target resolution can be obtained in various ways, one of which is: acquiring a resolution sample library; and retrieving a resolution sample meeting a preset condition with the resolution of the first image from the resolution sample library as a target resolution. The preset condition may be to retrieve a resolution sample that is the smallest difference from the resolution of the first image. The other mode is as follows: receiving a target resolution input by a client, wherein the target resolution can be set by a user of the client according to various scaling attacks expected to be experienced by the first image; the other mode is as follows: and acquiring the target application, and setting the target resolution according to the resolution corresponding to the target application.

As shown in fig. 8, in step 802, a first scaling process is performed on the first image according to the target resolution to obtain a second image, where the resolution of the second image and the target resolution meet a first preset error range.

As shown in fig. 8, in step 803, the watermark information is embedded into the second image.

Embedding the watermark into the second image, including: embedding the watermark into frequency domain coefficients of the second image; and carrying out inverse transformation processing on the frequency domain coefficient of the second image to obtain the second image embedded with the watermark information.

The specific content of the second image with the embedded watermark information obtained by embedding the watermark into the frequency domain coefficient of the second image and performing inverse transformation on the frequency domain coefficient of the second image may refer to the related content in the first embodiment of the present application, and will not be described herein again.

As shown in fig. 8, in step 804, a second scaling process is performed on the second image embedded with the watermark information to obtain a third image, where the resolution of the third image and the resolution of the first image satisfy a second preset error range.

The first predetermined error range and the second predetermined error range may be the same.

The following describes the watermark embedding and extraction scenario in conjunction with fig. 9 and 10.

As shown in fig. 9, the interface of the watermark embedding end is a web page, the web page displays a first image selection button 9-1, the first image to be embedded with the watermark can be selected by inputting the path of the first image to be embedded with the watermark through the first image selection button, the web page also displays a watermark selection button 9-2, the watermark to be embedded can be selected through the watermark selection button, the target application can be selected according to the target application list 9-3, the target resolution is determined according to the selected target application, and after the first image, the embedded watermark and the target application are selected, the watermark embedding button 9-4 is pressed to generate a third image 9-5 embedded with the watermark.

As shown in fig. 10, a watermark extraction end (which may be an application provided in an instant messaging application) first obtains a third image of a watermark to be extracted through a third image selection button 10-1; obtaining a scrambling code according to the watermark code obtaining button 10-2; selecting a target application from the target application selection list 10-3, determining a target resolution according to the selected target application, extracting a watermark by pressing a watermark extraction button 10-4, extracting an embedded watermark, and finally performing copyright authentication 10-5 according to the extracted watermark.

Although the present invention has been described with reference to the preferred embodiments, it should be understood that the scope of the present invention is not limited to the embodiments described above, and that various changes and modifications may be made by one skilled in the art without departing from the spirit and scope of the present invention.

In a typical configuration, a computing device includes one or more processors (CPUs), input/output interfaces, network interfaces, and memory.

The memory may include forms of volatile memory in a computer readable medium, Random Access Memory (RAM) and/or non-volatile memory, such as Read Only Memory (ROM) or flash memory (flash RAM). Memory is an example of a computer-readable medium.

Computer-readable media, including both non-transitory and non-transitory, removable and non-removable media, may implement information storage by any method or technology. The information may be computer readable instructions, data structures, modules of a program, or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), Static Random Access Memory (SRAM), Dynamic Random Access Memory (DRAM), other types of Random Access Memory (RAM), Read Only Memory (ROM), Electrically Erasable Programmable Read Only Memory (EEPROM), flash memory or other memory technology, compact disc read only memory (CD-ROM), Digital Versatile Discs (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices, or any other non-transmission medium that can be used to store information that can be accessed by a computing device. As defined herein, computer readable media does not include non-transitory computer readable media (transient media), such as modulated data signals and carrier waves.

As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.