KR20060034677A - Method for protecting scalable video coding contents and its apparatus - Google Patents

Abstract

The present invention encrypts scalable video encoded content by only encrypting data for each encoding layer in terms of temporal scalability, spatial scalability, and image quality scalability in order to serve protected scalable video encoded content. In order to reduce the amount of computation required for encryption, and to protect the content by generating and distributing encryption keys required for encryption and de-encryption according to the usage level of the content consumer, the present invention for this purpose is to scale required from the scalable video user terminal A scalable video content protection method in a scalable video encoding content providing system that encrypts and provides flexible video content, the method comprising: acquiring the requested scalable video content and scaling the received scalable video content Storing the video content in the archive and controlling to generate an encryption key for authentication and delivery to the user, performing authentication and generating an encryption key, capturing scalable video on request, and capturing the scalable video content. Encrypting the encoded video, encrypting the encoded scalable video content using an encryption key generated, generating encrypted scalable video code and encryption information metadata about the content, and encrypting the encrypted scale. And transmitting the flexible video encoded content and the generated encryption information metadata to the scalable video user terminal through a network.

In addition, a scalable video content protection method in a scalable video user terminal for de-encrypting and decrypting encrypted scalable video encoded content and encryption information metadata received from a scalable video encoded content providing system, the received encrypted information metadata Interpreting the encryption information metadata from the data to obtain encryption keys and encryption information, deciphering using the received encrypted scalable video encoded content and the encryption key and encryption information, and inversely encrypted scalable video content. Decoding and playing. Therefore, a large amount of computation is not required in the process of de-encrypting the encrypted compressed video content, and in the case of the scalable video encoded content as in the past, the encryption of the data of each layer is performed as a whole, resulting in an inefficient amount of computation. There is an effect that can solve the problems coming.

Scalable, video, content, encryption, encoding, decryption

Description

METHOD FOR PROTECTING SCALABLE VIDEO CODING CONTENTS AND ITS APPARATUS}

1 is a temporal decomposition and synthesis diagram of a scalable video frame according to the present invention;

2 is a block diagram for MPEG-4 scalable video encoding;

3 is a structural diagram of temporal and spatial scalability for protecting scalable video encoded content according to the present invention;

4 is a block diagram of a fine granular scalability (GFS) block in a device for protecting MPEG-4 scalable video encoded content according to the present invention;

5 is a block diagram illustrating an apparatus for protecting scalable video encoded content according to the present invention;

<Description of Symbols for Main Parts of Drawings>

100: scalable video encoding content providing system

101: camera 102: video acquisition block

103: scalable video coding block

104: scalable video content service management block

105: user authentication and encryption key management block

106: scalable video encoded data encryption block

107: encryption information metadata generation block

108: encryption information metadata archive

109: Scalable Video Content Archive

110: content acquisition block

111: encryption scalable video encoding content and encryption information metadata transport block

112: Block receiving user content request information

200: scalable video user terminal

201: Encryption scalable video encoding content and encryption information metadata receiving block

202: Encryption scalable video metadata analysis block

203: scalable crypto video de-encryption block

204 scalable video decoding block

205: scalable decoded video rendering block

206: user interface block

207: Scalable video request and response reception block

The present invention relates to a method and a device for protecting scalable video encoded content, and more particularly, to provide scalable scalable video encoded content to service scalable video encoded content, respectively, in terms of temporal scalability and spatial scalability. In terms of reliability and quality scalability, only the data is encrypted for each coding layer, thereby reducing the amount of computation required for encryption and de-encryption, and generating and distributing the encryption key required for encryption and de-encryption according to the usage level of the content consumer. It relates to a method and an apparatus capable of protecting the.

As is well known, conventional compressed video content protection mainly uses a scheme of protecting a content by applying encryption at the time of packetizing the target video or encrypting and protecting the stored compressed video content itself.

However, the above encryption protection scheme has a disadvantage in that a large amount of computation is required in the process of de-encrypting the encrypted compressed video content. Also, in the case of scalable video encoded content, encryption of data of each layer is performed as a whole. There is a problem that leads to an inefficient calculation increase.

Accordingly, an object of the present invention is to solve the above-described problems, and an object thereof is to provide scalable temporal scalability, spatial scalability, and image quality of scalable video encoded content in order to serve protected scalable video encoded content. In terms of scalability, only data is encrypted for each encoding layer, thereby reducing the amount of computation required for encryption and de-encryption, and generating and distributing encryption keys required for encryption and de-encryption according to the level of use of content consumers to protect contents. The present invention provides a method and apparatus for protecting scalable video encoded content.

A scalable video content protection method in a scalable video encoded content providing system for encrypting and providing scalable video content requested from a scalable video user terminal in order to achieve the above object, the requested scalable method Obtaining video content, storing the received scalable video content in a scalable video content archive, controlling to perform authentication and generating an encryption key for delivery to the user, performing authentication and generating an encryption key, and Photographing scalable video according to a request, encoding the captured scalable video content, encrypting the encoded scalable video content using an encryption key generated for the encoded scalable video content, and encrypting the scalable video. Generating encrypted information metadata about the code and the content, and transmitting the encrypted scalable video encoded content and the generated encrypted information metadata to the scalable video user terminal through a network.

In another aspect of the present invention for achieving this object, a scalable video in a scalable video user terminal that de-encrypts and decrypts encrypted scalable video encoded content and encrypted information metadata received from a scalable video encoded content providing system. A content protection method comprising the steps of: obtaining encryption key and encryption information by interpreting encryption information metadata from received encryption information metadata, and performing reverse encryption using the received encrypted scalable video encoded content and encryption key and encryption information. And decrypting and playing back de-encrypted scalable video content.

In another aspect of the present invention for achieving the above object, a scalable video encoding content providing system for protecting a scalable video content from a scalable video user terminal, the user content request for receiving the requested scalable video content Scalable video content service management means for controlling information receiving means, storing received scalable video content in a scalable video content archive, and generating an encryption key for performing authentication and delivering to a user, performing authentication and generating an encryption key User authentication and encryption key management means, imaging means for capturing scalable video upon request, scalable video encoding means for encoding the captured scalable video content, and an encoded scalable video cone. Scalable video encoded data encryption means for encrypting using an encryption key generated for the content, encryption information metadata generating means for generating encrypted information metadata for encrypted scalable video code and content, and encrypted scalable And a means for transmitting the encrypted scalable video encoded content and the encrypted information metadata for transmitting the video encoded content and the generated encrypted information metadata to the scalable video user terminal through a network.

In another aspect of the present invention for achieving the above object, a scalable video user terminal for de-encrypting, decrypting and protecting encrypted scalable video encoded content and encrypted information metadata, the encrypted information in the received encrypted information metadata Encryption scalable video metadata analyzing means for analyzing the metadata to obtain an encryption key and encryption information, and scalable encryption video de-encryption means for inversely encrypting the received encrypted scalable video encoded content and the encryption key and encryption information. And scalable video decoding means for decoding the inversely encrypted scalable video content, and scalable decoded video rendering means for rendering and decoding the decrypted scalable video content.

Hereinafter, a plurality of embodiments of the present invention may exist, and a preferred embodiment will be described in detail with reference to the accompanying drawings. Those skilled in the art will appreciate the objects, features and advantages of the present invention through this embodiment.

1 is a temporal decomposition and synthesis diagram of a scalable video frame according to the present invention, FIG. 1A is a temporal decomposition diagram of a scalable video frame, and FIG. 1B is a temporal synthesis diagram of a scalable video frame.

First, referring to FIG. 1A, successive video frames are divided into each frame (picture) group, and each picture group is temporally filtered, and a low-pass filtered picture and a high-pass filtered picture each have a 1/2 time resolution and have one layer. The low pass filtering picture and the high pass filtering picture each having 1/2 time resolution are formed into lower layers. In other words, the temporal decomposition process continues until only one low pass filtering picture remains in the lowest layer.

Next, referring to FIG. 1B, the temporal synthesis process of the scalable video frame is an inverse process of the decomposition process, and the low pass of the same layer is obtained by using the high pass filtering picture of the lower layer from the low pass filtering picture of the lowest layer obtained in the decomposition process. Obtain the filtered picture. This process proceeds until the resolution of the original image is obtained.

In other words, in terms of transmitting temporally decomposed scalable video content, high-pass filtered pictures of the next higher layer are sequentially provided, starting with the lowest low-pass filtered picture. Here, in terms of scalable video protection, only the lowest low-pass filtered picture is encrypted to protect the synthesis of all the low-pass filtered pictures of the upper layer, and the high-pass filtered picture of the upper layer according to the allowed time resolution By encrypting, it is possible to allow temporal resolution of pictures only down to the corresponding layer.

FIG. 2 is a block diagram for MPEG-4 scalable video coding (AVC), in which original picture pictures are reduced in spatial resolution through downsampling or filtering, and pictures of reduced spatial resolution are assigned to encoding in a corresponding layer. Is entered. The lowest layer where the minimum spatial resolution pictures are encoded is encoded by MPEG-4 AVC or H.264 video encoding, and the higher layers are self-contained using motion, texture, and residual signals used when encoded in their very lower layer. Encode the input pictures of the layer. This coding structure is called coarse granular scalability. On the other hand, each encoding layer can be encoded with fine granular scalability, which can be encoded by dividing the picture quality into finer grades.

3 illustrates a temporal / spatial scalability structure diagram for protecting scalable video encoded content according to the present invention.

That is, referring to FIG. 3, the picture ◎ to the picture ④ represents a lower (n) hierarchical picture, and the picture ⑤ to the picture ⑨ represents a higher (n + 1) hierarchical picture. Here, lower (n) layer pictures are encoded by temporal decomposition, and upper (n + 1) layer pictures are encoded with the same temporal decomposition structure as pictures of lower (n) layer, and higher (n + 1) encoding ) Hierarchical pictures are encoded using motion vectors, textures, residual signals, and the like from pictures of their respective corresponding lower layer.

For example, picture (7) of the upper layer (n + 1) is encoded using motion, texture, residual signal, etc. used in encoding picture (2) of the lower layer (n), and pictures ⑤ and ⑨. Therefore, from the standpoint of scalable video content protection, when pictures ◎ and ④ are encrypted, they cannot be reproduced from pictures ①, ②, ③, and pictures ⑤ through ⑨ without reverse encryption. This is to protect scalable video content in a very effective way in terms of content protection.

4 shows a block diagram of a fine granular scalability (GFS) block in an apparatus for protecting MPEG-4 scalable video encoded content according to the present invention.

That is, the base layer of the FGS encodes the input image through transform, scaling, and quantization, decodes it through an inverse process, and obtains a residual signal from the original image. The residual signal is input and transformed and scaled, and finer quantization is performed than the quantization of the base layer of the FGS, and the result is entropy encoded.

On the other hand, the image decoded in this enhancement layer is obtained from the image decoded in the previous base layer and the residual signal is obtained again, and the result is used as the input of the next enhancement layer. This process is performed continuously up to the desired FGS layer. Here, in terms of content protection for FGS content, if a residual signal obtained from a lower layer is encrypted, subsequent decryption of the subsequent enhancement layers cannot be performed without inversely encrypting the residual signal.

1, 2, 3, and 4 described above will be described below with reference to FIG. 1A to protect scalable video encoded content considering temporal, spatial, and image quality scalability.

That is, in Fig. 1a L ₃ lowpass filtering the picture in the lowest layer in the base layer is the most when an underlying picture encoding the L ₃ picture successfully station is one of a picture group without encrypting L ₃ pictures (GoP: Group of pictures), and since all of the picture groups of the base layer cannot be decoded, all of the pictures of the upper layer can also be decoded.

Thus, if only the L ₃ picture is encrypted in the base layer and only the remaining H ₃ high band filtering pictures are encrypted, only one L ₃ picture in the picture group can be decrypted. L _3, only the picture of the lowest layer corresponding to a lowest layer L _3-picture of the base layer in the enhancement layer thus can be decoded. In addition, when only the L ₃ picture of the base layer is allowed to be decoded and the corresponding L ₃ pictures of the enhancement layers are to be protected, only the L ₃ picture coded data of the enhancement layer is protected so that the L ₃ picture decoding of the higher enhancement layers is decoded. It is impossible to do without precedence.

Similarly, to protect a higher resolution picture without protecting the L ₂ picture, only the H ₂ highband filtered picture is encrypted. To protect a higher resolution picture without protecting the L ₁ picture, the H ₁ highband filtered picture You only need to encrypt them.

In addition, the L ₃ low-band filtering picture and the H ₃ , in the temporal resolution layer of the base layer. H ₂ and By encrypting H ₁ high-bandwidth filtered pictures with different encryption keys and restricting the disclosure of encryption keys to different groups of users according to their business model, groups of users can choose content at different scalability levels for the same scalable video content. There is an advantage that can be controlled to consume.

5 is a block diagram illustrating an apparatus for protecting scalable video encoded content according to the present invention.

That is, the scalable video encoding content providing system 100 includes a camera 101 which is a video acquisition device, a video acquisition block 102, a scalable video encoding block 103, a scalable video content service management block 104, and a user. Authentication and encryption key management block 105, scalable video encoded data encryption block 106, encryption information metadata generation block 107, encryption information metadata archive 108, scalable video content archive 109, content An acquiring block 110, an encrypted scalable video encoded content, an encrypted information metadata transmission block 111, and a user content request information receiving block 112.

The scalable video user terminal 200 may be a wired terminal (eg, a computer having network connection means, etc.) or a wireless terminal (eg, cellular phone, PCS, PDA, IMT-2000, PDA phone, smart phone, etc.) Encrypted scalable video encoded content and encrypted information metadata receiving block 201, encrypted scalable video metadata parsing block 202, scalable encrypted video de-encrypting block 203, scalable video decrypting block 204, scale A flexible decoded video rendering block 205, a user interface block 206, a scalable video request and response receiving block 207.

Based on the above-described configuration, a process of operating the apparatus for protecting scalable video encoded content according to the present invention will be described in more detail.

Referring to FIG. 5, the user interface block 206 in the scalable video user terminal 200 requests the scalable video encoded content providing system 100 through the network 300 for scalable video content.

Then, the scalable video encoding content providing system 100 receives scalable video content according to a user's request through the user content request information receiving block 112 and inputs the scalable video content to the scalable video content service management block 104.

The scalable video content service management block 104 receives the scalable video content and stores it in the scalable video content archive 109 while controlling the user authentication and encryption key management block 105 to perform authentication and encryption to be delivered to the user. Generate a key.

At this time, the camera 101 captures a video for generating the requested scalable video content under the control of the scalable video content service management block 104. Then, the scalable video content generated in the video stroke blocks 102 is obtained and provided to the scalable video coding block 103.

The scalable video encoding block 103 performs an encoding process on the provided scalable video content and provides it to the scalable video code data encryption block 106.

The scalable video code data encryption block 106 encrypts the encoded scalable video content using an encryption key received from the user authentication and encryption key management block 105 to encrypt the scalable video encoded content and the encryption information. The metadata transport block 111 and the encryption information metadata generation block 107.

In this case, the encryption information metadata generation block 107 generates encryption information metadata for the encrypted scalable video code and the content provided from the scalable video code data encryption block 106 to encrypt the encryption information metadata archive 108. The data is stored at the same time and input to the encrypted scalable video encoded content and the encrypted information metadata transport block 111.

Then, the encrypted scalable video encoded content and encrypted information metadata transport block 111 receives the encrypted scalable video encoded content from the scalable video coded data encryption block 106, and encrypts the generated encrypted information metadata. The data is input from the information metadata generation block 107 and transmitted to the scalable video user terminal 200 through the network 300.

Meanwhile, referring to FIG. 5, the scalable scalable video encoded content and encryption information metadata receiving block 201 in the scalable video user terminal 200 may be encrypted scalable video encoded content and encrypted information through the network 300. Receive metadata. At this time, the encryption scalable video metadata analysis block 202 interprets the encryption information metadata to obtain an encryption key and related encryption information and transmits the encryption key and related encryption information to the scalable encryption video de-encryption block 203.

The scalable encrypted video de-encryption block 203 is the encrypted scalable video encoded content fetched from the encrypted scalable video encoded content and the encrypted information metadata receiving block 201, and the encrypted scalable video metadata analyzing block 202. An inverse encryption process is performed using the encryption key and the related encryption information provided from the N-S 1, and provided to the scalable video decryption block 204.

The scalable video decryption block 204 decrypts the scalable video content subjected to the inverse encryption process and provides the decrypted video content to the scalable decoded video rendering block 205.

The scalable decoded video rendering block 205 renders the decoded scalable video content and reproduces it through an output means (not shown) via the user interface 206.

Accordingly, the present invention encrypts scalable video encoded content by only encrypting data for each encoding layer in terms of temporal scalability, spatial scalability, and quality scalability in order to serve protected scalable video encoded content. And the amount of computation in the process of de-encrypting encrypted compressed video content by reducing the amount of computation required for de-encryption and protecting the content by generating and distributing the encryption keys required for encryption and de-encryption according to the usage level of the content consumer. In addition, in the case of the scalable video encoded content as in the past, the problem that an inefficient calculation amount is increased may be solved as the encryption of the data of each layer is performed as a whole.

In addition, since the present invention is disclosed as a right within the spirit and claims of the present invention, the present invention may include any modification, use and / or adaptation using general principles, and the present invention as a matter deviating from the description of the present specification. It includes everything that falls within the scope of known or customary practice in the art to which it belongs and falls within the scope of the appended claims.

As described above, the present invention encrypts the scalable video encoded content only for each coding layer in terms of temporal scalability, spatial scalability, and quality scalability in order to serve the protected scalable video encoded content. This reduces the amount of computation required for encryption and de-encryption, and protects the content by generating and distributing the encryption keys required for encryption and de-encryption according to the content consumer's usage level. There is no need for a calculation amount, and in the case of the scalable video encoding content as in the past, the encryption that is performed on the data of each layer as a whole has an effect of solving the problem of an inefficient calculation increase.

Claims (24)

A scalable video content protection method in a scalable video encoding content providing system for encrypting and providing scalable video content requested from a scalable video user terminal, Acquiring the requested scalable video content; Storing the received scalable video content in a scalable video content archive and simultaneously performing authentication and generating an encryption key for delivery to a user; Performing the authentication and generating an encryption key; Capturing scalable video according to the request, and encoding the captured scalable video content; Encrypting the encoded scalable video content using the generated encryption key; Generating encryption information metadata on the encrypted scalable video code and content; Transmitting the encrypted scalable video encoded content and the generated encrypted information metadata to the scalable video user terminal through a network or a storage medium. A method of protecting scalable video encoding content comprising a. The method of claim 1, And the encryption selectively performs encryption on a low pass filtering picture decomposed in a lower layer or a high pass filtering picture in an upper layer with respect to an input video temporal decomposition picture of a base layer. The method of claim 1, And the encryption encrypts a base layer or an enhancement layer with respect to the encoded data of the FGS layer encoded to have image quality scalability. The method of claim 1, The encryption information metadata includes an encryption parameter and an encryption key. A method of protecting scalable video content in a scalable video user terminal for de-encrypting and decrypting encrypted scalable video encoded content and encrypted information metadata received from a scalable video encoded content providing system, Analyzing encryption information metadata from the received encryption information metadata to obtain an encryption key and encryption information; Inversely encrypting the received encrypted scalable video encoded content and the encryption key and encryption information; Decrypting and playing the inversely encoded scalable video content A method of protecting scalable video encoding content comprising a. The method of claim 5, wherein The encryption information metadata includes an encryption parameter and an encryption key. The method of claim 5, wherein And a method for acquiring, installing, and using the inverse encryption tool through a storage medium or a network when the inverse encryption tool does not exist in the inverse encryption process. The method of claim 5, wherein If there is no encryption metadata for reverse encryption in the reverse encryption process, request encryption metadata required for reverse encryption through a network, and receive and obtain encryption metadata corresponding to the request to obtain a scalable scalable ratio. A method of protecting scalable video encoded content, characterized in that it is applied to a process of inverse encryption of video data. A scalable video encoding content providing system for protecting scalable video content requested from a scalable video user terminal, User content request information receiving means for receiving the requested scalable video content; Scalable video content service management means for storing the received scalable video content in a scalable video content archive and controlling to perform authentication and to generate an encryption key for delivery to a user; User authentication and encryption key management means for performing the authentication and generating an encryption key; Imaging means for capturing scalable video according to the request; Scalable video encoding means for encoding the captured scalable video content; Scalable video encoded data encryption means for encrypting the encoded scalable video content using the generated encryption key; Encryption information metadata generating means for generating encryption information metadata for the encrypted scalable video code and content; Means for transmitting the encrypted scalable video encoded content and the encrypted information metadata to transmit the encrypted scalable video encoded content and the generated encrypted information metadata to the scalable video user terminal through a network. Apparatus for protecting scalable video encoding content comprising a. The method of claim 9, The scalable video encoded data encryption means for encrypting the encoded scalable video content using the generated encryption key performs encryption on the encoded data of temporal, spatial, and image quality scalability layers, respectively. A device for protecting scalable video encoded content, characterized in that encryption is performed on any combination of spatial and image quality scalability layers. The method of claim 10, The scalable video encoding data encryption means selectively encrypts a low pass filtering picture decomposed in a lower layer or a high pass filtering picture of a higher layer with respect to an input video temporal decomposition picture of a base layer. Device for protecting encoded content. The method of claim 10, And the scalable video encoded data encryption means encrypts a base layer or an enhancement layer for encoded data of an FGS layer encoded to have image quality scalability. The method of claim 9, And the encryption information metadata includes an encryption parameter and an encryption key. A scalable video user terminal for inversely encrypting, decrypting, and protecting encrypted scalable video encoded content and encrypted information metadata, wherein: Encryption scalable video metadata analyzing means for analyzing encryption information metadata from the received encryption information metadata to obtain an encryption key and encryption information; Scalable encrypted video de-encryption means for inverse encryption using the received encrypted scalable video encoded content and the encryption key and encryption information; Scalable video decrypting means for decrypting the inversely encoded scalable video content; Scalable decoded video rendering means for rendering and decoding the decoded scalable video content Apparatus for protecting scalable video encoding content comprising a. The method of claim 14, And the encryption information metadata includes an encryption parameter and an encryption key. The method of claim 14, The scalable encrypted video deciphering means obtains, installs and uses a deciphering tool through a storage medium or a network when the deciphering tool does not exist when performing reverse encryption. Protection device. The method of claim 14, The scalable encrypted video de-encryption means requests encryption metadata for de-encryption through a storage medium or a network when there is no encryption metadata for de-encryption when performing reverse encryption, and corresponds to the request. A device for protecting scalable video encoded content, characterized by receiving and acquiring encrypted metadata and applying it to de-encryption of encrypted scalable video data. An apparatus for protecting scalable video encoded content, Input means for inputting input video data obtained by a request of a video user terminal into one or more temporal, spatial and image quality scalability layers; Encoding means for encoding the input video data of the input temporal, spatial and image quality scalability layer; Encryption means for encrypting the video data of the encoded temporal, spatial and image quality scalability layers; Generating means for generating metadata for video data of the encrypted temporal, spatial and quality scalability layers; Storage means for storing the encoded data of the encrypted temporal, spatial and image quality scalability layers in combination with the generated metadata; Apparatus for protecting scalable video encoding content comprising a. The method of claim 18, And the encryption means selectively encrypts a low pass filtering picture decomposed in a lower layer or a high pass filtering picture of an upper layer with respect to an input video temporal decomposition picture of a base layer. . The method of claim 18, And said encryption means encrypts a base layer or an enhancement layer with respect to coded data of an FGS layer encoded to have image quality scalability. The method of claim 18, And the metadata includes an encryption parameter and an encryption key. The method of claim 18, The encryption means for encrypting the video data of the encoded temporal, spatial and quality scalability layers performs encryption on the encoded data of the temporal, spatial and quality scalability layers, respectively, or the temporal, spatial and quality scales. A device for protecting scalable video encoded content, characterized in that encryption is performed on any combination of security layers. A method of protecting scalable video encoded content, Inputting the input video data obtained at the request of the video user terminal into one or more temporal, spatial and image quality scalability layers; Encoding the input video data of the input temporal, spatial and image quality scalability layer; Encrypting video data of the encoded temporal, spatial and image quality scalability layers; Generating metadata for video data of the encrypted temporal, spatial and quality scalability layers; Storing the encoded data of the encrypted temporal, spatial and image quality scalability layers in combination with the generated metadata; A method of protecting scalable video encoding content comprising a. The method of claim 23, Encrypting the encoded video data of the temporal, spatial and quality scalability layer encodes the encoded data of the temporal, spatial and quality scalability layer, respectively, or temporally, spatial and quality scalability. A method of protecting scalable video encoded content, characterized in that encryption is performed on any combination of roughness layers.

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