KR102050882B1 - Method, server and computer-readable recording media for video security using zero-watermarking based on stream cipher - Google Patents

Abstract

The present invention relates to a method, a server, and computer-readable recording media for video security using zero-watermarking based on stream cipher. According to an embodiment of the present invention, the method for video security using zero-watermarking based on stream cipher comprises: a step of acquiring information about a video including first to N^th (N is natural numbers which is one or higher) video frames; a step of generating encrypted video frames corresponding to each of the first to N^th video frames based on a counter mode of a block cipher; and a step of generating a watermark key corresponding to each of the first to N^th image frames. An i^th encrypted video frame corresponding to the i^th video frame (i is a natural number less than or equal to N) of the first to N^th video frames is generated based on the i^th video frame and a counter value corresponding to the i^th video frame. The watermark key corresponding to the i^th video frame is generated based on a feature point of the i^th video frame and the counter value corresponding to the i^th video frame. Accordingly, the present invention prevents tampering with the video while streaming the video in real time.

Description

TECHNICAL SERVER, COMPUTER-READABLE RECORDING MEDIA FOR VIDEO SECURITY USING ZERO-WATERMARKING BASED ON STREAM CIPHER}

The present invention relates to a video security method using a stream cipher based zero-watermarking, a server and a computer-readable recording medium.

Recently, as the misuse, abuse and invasion of privacy of personal image information increases, it is a trend to stipulate the principle of protection of personal image information and standards for each step and strengthen the damage relief system.

In this trend, technology-based countermeasures for security of images are needed. That is, systems capable of acquiring an image and distributing the acquired image should be equipped with a function for preventing modulation on the image as an essential function.

Republic of Korea Patent Publication No. 10-2014-0140928

The object of the present invention is to solve all the above-mentioned problems.

In addition, the problem to be solved by the present invention is to apply a zero watermark technique with a high-speed operation, to prevent the image, the modulation and the modulation while streaming the image in real time.

Specifically, the problem to be solved by the present invention is to increase the confidentiality and integrity of the security by applying the encryption operation and the watermark insertion operation to the image frame at the same time, encrypting the image frame and inserting the watermark in the image frame Is performed at the same time, so that the video can be secured in real time in a streaming environment.

Representative configuration of the present invention for achieving the above object is as follows.

According to an embodiment of the present invention, a video security method using stream cipher-based zero-watermarking may include obtaining information about an image including first to Nth (N is one or more natural numbers) th image frames. ; Generating encrypted image frames corresponding to each of the first through N th image frames based on a counter mode of a block cipher; And generating a watermark key corresponding to each of the first to Nth image frames, and corresponding to an i (i is a natural number of N or less) image frame among the first to Nth image frames. The i-th encrypted video frame is generated based on the i-th video frame and the counter value corresponding to the i-th video frame, and the watermark key corresponding to the i-th video frame includes: The image may be generated based on a feature point of the i-th image frame and the counter value corresponding to the i-th image frame.

In addition, according to an embodiment of the present invention, the video security server using stream cipher-based zero-watermarking acquires information on an image including first to Nth (N is a natural number of 1 or more) th frame. An image acquisition unit; And an image processor configured to generate encrypted image frames corresponding to each of the first to Nth image frames and to generate a watermark key corresponding to each of the first to Nth image frames. The i th encrypted image frame corresponding to the i th image frame (i is a natural number less than or equal to N) among 1 to N th image frames corresponds to the i th image frame and the i th image frame. The watermark key is generated based on a counter value, and the watermark key corresponding to the i-th image frame is generated based on a feature point of the i-th image frame and the counter value corresponding to the i-th image frame. It may be characterized by.

In addition, there is further provided a computer readable recording medium for recording another method for implementing the present invention, another system, and a computer program for executing the method.

According to the present invention, by applying a zero watermark technique with a high-speed operation, it is possible to prevent the modulation and the like to the image while streaming the image in real time.

In addition, according to the present invention, by applying the encryption operation and the watermark insertion operation to the image frame at the same time to increase the confidentiality and integrity of the security, the step of encrypting the image frame and the step of inserting the watermarking on the image frame to be performed at the same time In addition, it can ensure video security in real time in a streaming environment.

1 is a view showing a schematic configuration of an entire system for encrypting an image according to an embodiment of the present invention.
2 is a diagram illustrating in detail the internal configuration of the server according to an embodiment of the present invention.
3 is a diagram for explaining a block cipher.
4 and 5 are diagrams for explaining the counter mode of the block cipher mode.
6 is a diagram schematically illustrating an image processing algorithm according to an embodiment of the present invention.
7 is a flowchart illustrating an image processing method according to an embodiment of the present invention.
8 illustrates a computing device, in accordance with an embodiment of the invention.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and like reference numerals designate like parts throughout the specification.

In this specification, duplicate descriptions of the same components are omitted.

Also, in the present specification, when a component is referred to as being 'connected' or 'connected' to another component, the component may be directly connected to or connected to the other component, but in between It will be understood that may exist. On the other hand, in the present specification, when a component is referred to as 'directly connected' or 'directly connected' to another component, it should be understood that there is no other component in between.

Also, the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

Also, in this specification, the singular forms may include the plural forms unless the context clearly indicates otherwise.

Also, as used herein, the term 'comprises' or 'having' is only intended to designate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more. It is to be understood that it does not exclude in advance the possibility of the presence or addition of other features, numbers, steps, actions, components, parts or combinations thereof.

Also in this specification, the term 'and / or' includes any combination of the plurality of listed items or any of the plurality of listed items. In the present specification, 'A or B' may include 'A', 'B', or 'both A and B'.

Also, in the present specification, detailed descriptions of well-known functions and configurations that may blur the gist of the present invention will be omitted.

1 is a view showing a schematic configuration of an entire system for encrypting an image according to an embodiment of the present invention.

As shown in FIG. 1, the entire system according to an embodiment of the present invention may include a communication network 100, a server 200, and a user's terminal device 300.

First, the communication network 100 according to an embodiment of the present invention may be a high-speed network of a large communication network capable of data transmission / reception services, and provides Wi-Fi for providing an Internet or high-speed multimedia service. It may be a next generation wireless network including WiGig, Wireless Broadband Internet (Wibro), and WiMAX (World Interoperability for Microwave Access, Wimax).

The Internet includes various services existing in the TCP / IP protocol and its upper layers, namely, Hyper Text Transfer Protocol (HTTP), Telnet, File Transfer Protocol (FTP), Domain Name System (DNS), Simple Mail Transfer Protocol (SMTP), It may refer to a global open computer network structure that provides a simple network management protocol (SNMP), a network file service (NFS), a network information service (NIS), and the like, and the user terminal device 300 is connected to the server 200. It can provide an environment that makes it possible.

The Internet may be a wired or wireless internet, or may be a core network integrated with a wired public network, a wireless mobile communication network, or a portable internet.

If the communication network 100 is a mobile communication network, it may be a synchronous mobile communication network or an asynchronous mobile communication network. As an example of the asynchronous mobile communication network, a communication network of a wideband code division multiple access (WCDMA) scheme may be used. In this case, although not shown in the figure, the mobile communication network may include, for example, a Radio Network Controller (RNC). Meanwhile, although the WCDMA network is taken as an example, it may be an IP network based on a next generation communication network such as 3G LTE network, 4G network, 5G network, or other IP.

Next, the server 200 according to an embodiment of the present invention may receive an image from the outside through the communication network 100 and perform a function of inserting a watermark while encrypting the received image.

The configuration and function of the server 200 according to the present invention will be described in detail through the following detailed description.

On the other hand, the user terminal device 300 according to an embodiment of the present invention is a digital device including a function that can communicate after connecting to the server 200, desktop computer, notebook computer, workstation, PDA, Web pad For example, any digital device having a memory means such as a mobile phone and a microprocessor can be adopted as the user terminal device 300 according to the present invention.

Hereinafter, the internal structure of the server according to the present invention and the function of each component will be described.

2 is a diagram illustrating in detail the internal configuration of the server according to an embodiment of the present invention.

As shown in FIG. 2, the server 200 according to an embodiment of the present invention includes an image acquisition unit 210, an image processing unit 220, a database 230, a communication unit 240, and a control unit 250. Can be configured. According to an embodiment of the present invention, at least some of the image acquisition unit 210, the image processing unit 220, the database 230, the communication unit 240, and the control unit 250 communicate with the user terminal device 300. It may be a program module. Such program modules may be included in the server 200 in the form of operating systems, application modules or other program modules, and may be physically stored in various known storage devices. In addition, such a program module may be stored in a remote storage device that can communicate with the server 200. On the other hand, such program modules include, but are not limited to, routines, subroutines, programs, objects, components, data structures, etc. that perform particular tasks or execute particular abstract data types, described below, in accordance with the present invention.

The image acquisition unit 210 according to an embodiment of the present invention may receive information about an image to be encrypted from the outside. When the captured image is formed of the first to Nth (N is one or more natural numbers) image frames, the image acquirer 210 generates information on each of the first to Nth image frames to generate an image processor 220. ) Can be delivered.

The image processor 220 may encrypt the image and generate a watermark key for the image by using the zero watermark. In the present invention, an image encryption operation and a watermark key generation operation may be performed in image frame units.

More specifically, the image processing unit 220 encrypts an image frame using a CTR (CounTeR, Counter) mode among block cipher modes, and acquires an encrypted image frame by using feature values and watermark images of the image frame. A watermark key can be generated.

Hereinafter, the meaning of the counter mode of the block cipher will be described in detail with reference to FIGS. 3 to 5.

3 is a diagram for explaining a block cipher.

A block cipher may refer to a cryptographic algorithm that processes a 'set' of a specific number of bits at a time, where 'set' may be referred to as a block. Referring to FIG. 3, in a block cipher algorithm, a ciphertext block in which a plaintext block is encrypted may be generated by using a plaintext block and a key to be encrypted, and conversely, a ciphertext block is decrypted using a ciphertext block and a key. You can create a block.

4 and 5 are diagrams for explaining the counter mode of the block cipher mode.

In the present specification, the counter mode may refer to a technique of generating a key stream by encrypting a counter that increases by 1 each time a block is encrypted.

The initial value of the counter can be created based on a different value (nonnce, non-table) for each encryption. If the block length is 128 bits (16 bytes), the initial value of the counter can be as shown in FIG. The first 8 bytes may indicate non-marking, the last 8 bytes may indicate a block number, and the number corresponding to the block number may be counted and incremented by one.

Referring to FIG. 5, a ciphertext block may be generated as a result of performing an XOR (exclusive OR) between a bit string encoding a counter and a plaintext block. In this case, the initialization counter value for the plain text block 1, the counter value for the plain text block 2, the counter value for the plain text block 3, and the counter value for the plain text block 4 may be as shown in FIG. 4 (b).

Hereinafter, a detailed method of encrypting an image frame and generating a watermark key in the image processor 220 according to an embodiment of the present invention will be described with reference to FIGS. 6 and 7.

6 is a diagram schematically illustrating an image processing algorithm according to an embodiment of the present invention.

Referring to FIG. 6, in the present invention, one image frame may correspond to a plain text block, and the image frame in which the image frame is encrypted may correspond to an encryption block.

In FIG. 6, 'IV' may mean an initialization vector, and for example, may have a length of 128 bits. In this case, the initialization vector may mean the initialization counter value described above with reference to FIGS. 4 and 5. In addition, 'K' may mean an encryption key, and for example, may have a length of 128 bits. 'Counteri' (i is a natural number greater than or equal to 1 and less than or equal to N) may mean a value increased by i from a value of 'IV' and may be the counter value described above with reference to FIGS. 4 and 5. 'E' may mean a 128-bit block cipher Lightweight Encryption Algorithm (LEA) function. 'Ii' may mean information about the i th image frame, that is, the i th plaintext block. 'I'i' may mean information on the i-th encrypted image frame, that is, the i-th encryption block. 'W' may mean a watermark image, and 'Si' may mean a watermark key corresponding to the i-th image image.

The image processor 220 applies the i-th encrypted by applying a round key value (encrypted counter value) generated by using the initialization vector IV, the encryption key K, and the LEA function to the i-th image frame Ii. An image frame I'i may be generated.

The LEA function is an algorithm for encrypting a 128-bit data block. The LEA function may include a key schedule function for generating a round key value and a round function for generating a ciphertext block from a plaintext block using the round key value.

The image processor 220 may generate an encrypted i-th image frame I'i by taking an XOR of the round key value and the i-th image frame Ii.

In addition, the image processor 220 extracts a feature point of the i-th image frame Ii and applies an initialization vector IV and a watermark image W to the extracted feature point, and then applies the i-th watermark key Si. ) Can be created. Feature points extracted through the features from accelerated segment test (FAST) algorithm may be used for coordinate information to hide the watermark.

The generated watermark keys S1 to SN may be registered with a trusted authority, and then downloaded if necessary and compared with those extracted from the image requiring verification, thereby forging or tampering with the image.

In general, in an environment where an image is streamed, it is not easy to insert a watermark in real time to prevent image forgery and / or modulation. However, according to the embodiment of the present invention, since each image frame is processed in parallel quickly (for example, encryption and zero watermark insertion of the image frame), the image is forged and / or modulated while streaming the image in real time. Can be prevented.

7 is a flowchart illustrating an image processing method according to an embodiment of the present invention.

Referring to FIG. 7, first, image frame information of an image to be encrypted may be obtained from the outside (S100). Here, the image frame information may correspond to the plain text block in the block cipher technique.

When the image frame information is obtained, the step of encrypting the image (S210, S220) and the step of generating a watermark key (S310, S320) may be performed together.

In detail, in order to obtain an encrypted image, a round key may be generated based on an initialization vector and an encryption key (S210). The round key can be generated using the LEA function. When the round key is generated, an encrypted image frame may be generated using the generated round key and image frame information (S220).

Meanwhile, in addition to the step of encrypting the image, a step of extracting feature points of the obtained image frame may be performed to insert a zero watermark in the image (S310). The feature point of the image frame may be used for coordinate information to hide the watermark. When the feature point of the image frame is extracted, a watermark key may be generated by applying an initialization vector and a watermark image to the image frame (S320). The watermark key may be used later to detect whether the image is forged and / or modulated.

Next, in the database 230 according to an embodiment of the present invention, information about an image frame, an encrypted image, a watermark key, etc. constituting an image to be encrypted may be stored. Although the database 230 is illustrated as being included in the server 200 in FIG. 2, the database 230 may be configured separately from the server 200 according to the needs of those skilled in the art for implementing the present invention. . In addition, although only one database 230 is illustrated in FIG. 2, the present invention is not limited thereto, and a plurality of databases 230 may be provided according to the needs of those skilled in the art for implementing the present invention. On the other hand, the database 230 in the present invention is a concept that includes a computer-readable recording medium, and may be a broad database including not only a negotiated database but also a file system based on a file system. If the set can be retrieved to extract data, it can be the database 230 of the present invention.

Next, the communication unit 240 according to an embodiment of the present invention may perform a function of enabling data transmission / reception from / to the image acquisition unit 210, the image processing unit 220, and the database 230. . In addition, the communication unit 240 may perform a function to enable data transmission and reception between the server 200 and the user terminal device 300.

Finally, the controller 250 according to an embodiment of the present invention performs a function of controlling the flow of data between the image acquisition unit 210, the image processing unit 220, the database 230, and the communication unit 240. Can be. That is, the controller 250 according to the present invention controls the data flow from / to the outside of the server 200 or the data flow between components of the server, thereby obtaining the image acquirer 210, the image processor 220, and the database. 230, and the communicator 240 may control to perform a unique function.

8 illustrates a computing device, in accordance with an embodiment of the invention. The computing device TN100 of FIG. 6 may be a device (eg, server 200, etc.) described herein.

In the embodiment of FIG. 8, the computing device TN100 may include at least one processor TN110, a transceiver device TN120, and a memory TN130. In addition, the computing device TN100 may further include a storage device TN140, an input interface device TN150, an output interface device TN160, and the like. Components included in the computing device TN100 may be connected by a bus TN170 to communicate with each other.

The processor TN110 may execute a program command stored in at least one of the memory TN130 and the storage device TN140. The processor TN110 may refer to a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor on which methods according to an embodiment of the present invention are performed. The processor TN110 may be configured to implement the procedures, functions, methods, and the like described in connection with an embodiment of the present invention. The processor TN110 may control each component of the computing device TN100.

Each of the memory TN130 and the storage device TN140 may store various information related to an operation of the processor TN110. Each of the memory TN130 and the storage device TN140 may be configured of at least one of a volatile storage medium and a nonvolatile storage medium. For example, the memory TN130 may be configured as at least one of a read only memory (ROM) and a random access memory (RAM).

The transceiver TN120 may transmit or receive a wired signal or a wireless signal. The transceiver TN120 may be connected to a network to perform communication.

Embodiments according to the present invention described above may be implemented in the form of program instructions that may be executed by various computer components, and may be recorded in a computer-readable recording medium. The computer-readable recording medium may include program instructions, data files, data structures, etc. alone or in combination. Program instructions recorded on the computer-readable recording medium may be those specially designed and configured for the present invention, or may be known and available to those skilled in the computer software arts. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks and magnetic tape, optical recording media such as CD-ROMs, DVDs, and magneto-optical media such as floptical disks. media), and hardware devices specifically configured to store and execute program instructions, such as ROM, RAM, flash memory, and the like. Examples of program instructions include not only machine code generated by a compiler, but also high-level language code that can be executed by a computer using an interpreter or the like. The hardware device may be configured to operate as one or more software modules to perform the process according to the invention, and vice versa.

On the other hand, the embodiment of the present invention is not implemented only through the apparatus and / or method described so far, but may be implemented through a program or a recording medium on which the program is recorded to realize a function corresponding to the configuration of the embodiment of the present invention. Such implementations can be readily implemented by those skilled in the art from the description of the above-described embodiments.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It belongs to the scope of the invention.

100: network 200: server
210: image acquisition unit 220: image processing unit
230: database `240: communication unit
250: control unit

Claims (13)

In the video security method using a stream cipher-based zero-watermarking,
Acquiring information about an image including first to N th (N is at least one natural numbers) image frames; And
Receiving i th image frame information, i.e., a feature point of the i th image frame, and a counter value corresponding to the i th image frame among the first to N th image frames, Generating an encrypted image frame corresponding to the i-th image frame and a watermark key corresponding to the i-th image frame;
The encrypted video frame is generated based on the i-th video frame information and a value obtained by encrypting the counter value.
The watermark key corresponding to the i th image frame is generated based on a feature point of the i th image frame and the counter value corresponding to the i th image frame.

The counter value, the value of which is incremented by one each time the image frame is encrypted, is used for generation of the encrypted image frame and also for generation of the watermark key.
The watermark key is generated through an XOR (exclusive OR) operation between a plurality of factors,
And the counter value is used as a factor of the XOR operation for generating the watermark key as it is. The method of claim 1,
The generating of the i th encrypted image frame includes:
Encrypting the counter value using an encryption key; And
Generating the i-th encrypted video frame by using the i-th video frame and the encrypted counter value. The method of claim 2,
The generating of the i th encrypted image frame is performed based on a Lightweight Encryption Algorithm (LEA) function. The method of claim 1,
Generating a watermark key corresponding to the i-th image frame includes:
Extracting feature points of the i-th image frame; And
And generating the watermark key using the feature point, the counter value, and a preset watermark image. The method of claim 4, wherein
The feature point of the i-th image frame is extracted using a fast (features from accelerated segment test) algorithm. The method of claim 1,
Generating the i-th encrypted image frame and generating a watermark key corresponding to the i-th image frame at the same time. A video security server using stream cipher based zero watermarking,
An image obtaining unit obtaining information about an image including first to N th (N is one or more natural numbers) th image frames; And
Receiving i th image frame information, i.e., a feature point of the i th image frame, and a counter value corresponding to the i th image frame among the first to N th image frames, And an image processor configured to generate an encrypted image frame corresponding to the i th image frame and a watermark key corresponding to the i th image frame.
The encrypted video frame is generated based on the i th video frame information and a counter value corresponding to the i th video frame.
The watermark key corresponding to the i th image frame is generated based on a feature point of the i th image frame and the counter value corresponding to the i th image frame.

The image processor is used to generate the encrypted image frame and to generate the watermark key using the counter value, the value of which increases by one each time the image frame is encrypted.
The watermark key is generated through an XOR (exclusive OR) operation between a plurality of factors,
And the counter value is used as a factor of the XOR operation for generating the watermark key as it is. The method of claim 7, wherein
The image processor,
And encrypting the counter value by using an encryption key and generating the i-th encrypted video frame by using the i-th image frame and the encrypted counter value. The method of claim 8,
The image processing unit, the server characterized in that for generating the i-th encrypted image frame using a Lightweight Encryption Algorithm (LEA) function. The method of claim 7, wherein
The image processor,
And generating the watermark key using the feature point, the counter value, and a preset watermark image. The method of claim 10,
The image processor,
And a feature point of the i th image frame is extracted using a fast (features from accelerated segment test) algorithm. The method of claim 7, wherein
The image processor,
And simultaneously generating a watermark key corresponding to the i-th encrypted image frame and the i-th image frame. A computer readable medium for recording a computer program for executing the method according to any one of claims 1 to 6.

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