KR20120045131A - Apparatus and method for encoding video, apparatus and method for decoding video - Google Patents

Abstract

PURPOSE: A video encoding apparatus and a method thereof are provided to insert respectively different watermark into a video and to easily extract purchaser information from a video. CONSTITUTION: A watermarking module(100) inserts a watermark into a video. A video encoding unit(110) encodes a video according to insertion of the watermark. A personal information-based video generating unit(120) selects a frame group of the video into which the watermark is inserted. The personal information-based video generating unit generates a personal information-based video.

Description

Apparatus and Method for Encoding Video, Apparatus and Method for Decoding Video}

Embodiments of the present invention relate to a video encoding apparatus and method, and a video decoding apparatus and method. More specifically, different buyers can insert different watermarks into the video, reduce the high computational cost in encoding the video, and if the video is leaked, buyer information can be extracted from the leaked video. The present invention relates to a video encoding apparatus and method, and a video decoding apparatus and method capable of extracting a watermark even after editing and recompressing a video by applying a watermarking method of directly inserting a watermark into the same.

The contents described in the following sections provide background information related to the embodiments of the present invention, but it does not constitute a prior art.

In general, in the case of video leakage through the capture of the output image, it is impossible to technically prevent the video leakage. Therefore, a watermark is detected from the leaked video after inserting an invisible signal in advance into the video image. Video watermarking is a technique for tracking the leakage path of an image.

Currently known video watermarking techniques include a method of inserting a watermark signal in a frequency region which is not sensitive to human vision, and an edge that is not sensitive to human vision even when the pixel region is changed according to the Human Visual System (HVS). There is a method of embedding a watermark signal in an area such as an edge) and a method of embedding a watermark in compressed video information.

To track the path of the leaked video, information about where the video came from must be inserted into the video as a watermark. The watermark to be inserted into the video should be inserted with different watermark information according to each buyer so that the individual who purchases the content can be distinguished.

However, the method of inserting a watermark in the video original image requires a high computation (computation) because the watermark must be inserted and compressed for each buyer.

When inserting a watermark into the compressed video information, it is very easy to insert a watermark for each buyer, but when the user edits and recompresses the video, the inserted watermark is damaged and difficult to detect.

An embodiment of the present invention is to provide a video encoding apparatus and method, a video decoding apparatus and method that can lower the operation while inserting different watermark information for each buyer.

According to an aspect of the present invention, there is provided a video encoding apparatus comprising: a watermarking module for generating and outputting a watermark embedded video by inserting a watermark into a video; A video encoding unit for dividing and encoding the video without the watermark into an arbitrary frame group, receiving the watermark embedded video, and dividing and encoding the watermark embedded video in the same manner as the arbitrary frame group; And generating a personal information-based video by selecting one of an arbitrary frame group of the non-watermarked video and an arbitrary frame group of the watermark-embedded video according to buyer information to generate and output a personal information-based video. It is characterized by including a wealth.

In addition, the video decoding apparatus according to an embodiment of the present invention receives a personal information-based video formed by combining a watermark-inserted frame group and the watermark-uninserted frame group, and randomly receives the received personal information-based video. A frame divider for dividing and outputting the frame into groups; A decoding unit for decoding the divided arbitrary frame group; A watermark detector for determining whether a watermark is detected in each of the decoded arbitrary frame groups, and outputting different detection signals according to whether the watermark is detected; And a purchaser information generation unit for comparing the purchaser information stored in the memory with the purchaser identification signal formed by combining the detection signal to identify the purchaser and outputting information on the confirmed purchaser.

A video encoding method according to an embodiment of the present invention includes the steps of: generating and outputting a watermark embedded video by embedding a watermark in the video; Dividing and encoding the video having no watermark embedded into an arbitrary frame group, receiving the watermark embedded video, and encoding the watermark embedded video by dividing the watermark embedded video in the same manner as the arbitrary frame group; And generating and outputting a personal information-based video by selecting one of an arbitrary frame group of the non-watermark embedded video and an arbitrary frame group of the watermark embedded video according to the purchaser information. It is done.

In addition, the video decoding method according to an embodiment of the present invention receives a personal information-based video formed by combining a frame group with a watermark and a frame group without the watermark, and randomly receives the received personal information-based video. Dividing into a frame group of the output; Decoding the video in the divided group of frames; Determining whether a watermark is detected in each of the decoded arbitrary frame groups, and outputting different detection signals according to whether the watermark is detected; And comparing the buyer information stored in the memory with the buyer identification signal formed by combining the detection signal to identify the buyer and outputting information on the confirmed buyer.

According to an exemplary embodiment of the present invention, buyer information can be easily extracted from the leaked video while eliminating a high calculation amount generated in the process of inserting and encoding different watermarks into an image for each buyer.

In addition, the watermarking method of inserting a watermark directly on the original image can be applied to extract the watermark even after editing and recompressing the video.

1 is a block diagram of a video encoding apparatus according to an embodiment of the present invention;
2 is a block diagram of a video decoding apparatus according to an embodiment of the present invention;
3 is a diagram illustrating an encoding method of the video encoding apparatus of FIG. 1;
4 is a diagram illustrating a decoding method of the video decoding apparatus of FIG. 2.

Hereinafter, some embodiments of the present invention will be described in detail through exemplary drawings. In adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are assigned to the same components as much as possible even though they are shown in different drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

In addition, in describing the component of this invention, terms, such as 1st, 2nd, A, B, (a), (b), can be used. These terms are only for distinguishing the components from other components, and the nature, order or order of the components are not limited by the terms. If a component is described as being "connected", "coupled" or "connected" to another component, that component may be directly connected to or connected to that other component, but there may be another configuration between each component. It is to be understood that the elements may be "connected", "coupled" or "connected".

1 is a block diagram of an encoding apparatus according to an embodiment of the present invention.

As shown in FIG. 1, a video encoding apparatus according to an embodiment of the present invention includes a watermarking module 100, a video encoding unit 110, and a purchaser video generating unit 120.

The watermarking module 100 receives a video of unit content and inserts a watermark signal into each frame of the input video. Here, the frame represents an information unit capable of forming a unit screen. At this time, a watermark is not inserted into a frame to be compressed with I or P, which can be used as a motion prediction reference image of another frame. In other words, a watermark is inserted into a P or B frame which is not used as a reference image of motion prediction, and provided to the second encoder 113. Here, I means Intra, and means the method of using the information in the frame, P means the method of using the information of the previous frame among the Inter, B is the frame before and after among the Inter This method uses all of the information. I and P frames used as reference images for motion prediction are not inserted into watermarks, so that I and P frames are used as reference images for motion estimation in video encoded before watermark and encoded video after watermark insertion. Are encoded equally. Therefore, video decoding is possible even if a new video is formed by recombining two videos after dividing the video with the watermark and the non-inserted video into frame groups based on I and P frames used as reference images for motion prediction. . However, the recombination video at this time means that one video is randomly selected from two frame groups in which time information coincides with two videos.

The video encoding unit 110 includes first and second encoding units 111 and 113, the first encoding unit 111 encodes a video without a watermark inserted, and the second encoding unit 113 The watermarking module 100 encodes the provided video by inserting a watermark into frames P and B which are not used for motion prediction more precisely. The first and second encoders 111 and 113 may include a transformer, a quantizer, and an encoder, and may further include a predictor and a decoder. The transform unit is, for example, a process of transforming a residual block of input video into a frequency domain as a DCT unit, a quantizer is a process of integerizing information converted into a frequency domain, and an encoder is a process of generating a bit stream by entropy coding, for example. In this case, the first and second encoding units 111 and 113 of the video encoding unit 110 are compressed in the form of “IBBPBBPBB …… BP” in the GOP layer during encoding. In the embodiment of the present invention, I and P are compressed. Random groups are set by dividing groups between frames and between P and P frames and used when generating a buyer video.

The buyer video generator 120 includes a personal information-based video generator 121 and a buyer information DB 123.

Here, the personal information-based video generating unit 121 is a video that does not have a watermark inserted by the first encoding unit 111, a watermark embedded video provided by the second encoding unit 113 and the buyer information DB In step 123, key information representing buyer information is provided, and a new video is generated by combining a video having a watermark and a non-watermarked video for each frame according to the key information.

The buyer information DB 123 stores key information and may provide key information stored in the buyer information DB 123 at the request of the personal information-based video generation unit 121. Here, the key information is a buyer signal formed by combining "0" and "1" as, for example, "10100100100" as a distinguishing signal for distinguishing each buyer.

2 is a block diagram of a decoding apparatus according to an embodiment of the present invention.

As shown in FIG. 2, the video decoding apparatus according to an embodiment of the present invention includes a frame splitter 200, a decoder 210, a watermark detector 220, a buyer information generator 230, and a buyer information DB. 240.

Here, the frame dividing unit 200 receives the watermarked personal information-based video provided by the encoding apparatus of FIG. 1 and divides it into frame groups. In this case, the number of frame groups will be equal to the number of buyer information, that is, the number of buyers.

The decoder 210 decodes the frames divided by the frame divider 200, that is, the watermark embedded video and the workmark non-inserted video. Since the decoder 210 may include a decoder, an inverse quantizer, an inverse transformer, and the like, the decoder 210 may reconstruct the original video through decoding, inverse quantization, and inverse transformation of the partitioned watermarked personal information-based video. Can be.

The watermark detection unit 220 determines whether a watermark is detected in the reconstructed group-specific frame, and extracts "1" if it is detected and "0" if it is not detected, and generates a buyer discrimination signal.

The buyer information generation unit 230 compares the purchaser identification signal provided by the watermark detection unit 220 with the buyer information stored in the buyer information DB 240 to confirm who the buyer is and output relevant buyer information.

In addition, since the watermark signal is repeatedly inserted, the buyer information generation unit 230 may detect the buyer distinction signal repeatedly, obtain the average value thereof, and compare the result with a predetermined value. Accordingly, the buyer information generator 230 may further include an average value calculator.

The buyer information DB 240 stores the buyer identification signal and the buyer information corresponding to the buyer identification signal, and provides them at the request of the buyer information generation unit 230. In addition, the buyer information DB 240 may further store information about a specific value.

3 is a diagram illustrating an encoding method of the encoding apparatus of FIG. 1.

Referring to FIG. 3 together with FIG. 1, in order to insert user information for each temporal frame, the encoding apparatus generates and then encodes a watermark embedded video and an uninserted video with respect to the input video at step S301.

When encoding, the encoding device selects a group of watermark embedded video or non-inserted video grouped into I ~ P, P ~ P frame units according to the buyer information according to the buyer information. A personal information-based video is generated by inserting key information into a video having N frame groups (S303).

For example, if the compression is performed in the form of "IBBPBBPBB …… BP" during encoding, the first "IBB" becomes a first group, and the next "PBB" becomes a second group. When the kth bit of the buyer information key is "1", the privacy-based video selects a specific frame of the kth framegroup corresponding to each other among the encoded watermark uninserted videos, and "0". Is generated by selecting a k-th frame group corresponding to each other among encoded watermark embedded videos.

While generating the privacy-based video in this manner, the encoding apparatus determines whether the generated privacy-based video is the N last frame group (S305).

If the number N of the frame groups is greater than the length K of the buyer information key rather than the last frame group, a bit of the n% K th buyer information key is inserted into the n th frame group (S307). Where n% K is the remainder of n divided by K.

4 is a diagram illustrating a decoding method of the decoding apparatus of FIG. 2.

As shown in FIG. 4, the decoding apparatus receives a watermarked personal information-based video provided by the encoding apparatus of FIG. 1 (S401). In this case, the watermarked personal information-based video may include a video without a watermark inserted.

Subsequently, the decoding apparatus divides the received watermarked personal information-based video into frame groups (S403). In other words, since the compression is performed in the form of "IBBPBBPBB …… BP" during encoding, the first "IBB" is divided into a first group, and the next "PBB" is divided into a second group. Split a group of frames.

As the standard for dividing the frame group is divided based on the time between I and P frames or the time between P and P frames when encoding, not the I and P frames, the interval between I and P frames is changed by editing and re-encoding the video. Can be avoided.

The decoding device decodes the video (S405). In this case, the decoding process may go through a process such as decoding, inverse quantization, and inverse transformation.

Subsequently, the watermark is detected from the video of the decoded frame group, and different detection signals are output according to detection (S407). For example, if a watermark is detected, a watermark is detected as a signal of "0". If a watermark is not detected, a watermark is detected as a signal of "1" to generate and output a buyer identification signal. If N is greater than K, the detection signal is repeatedly detected, and thus a signal detected by repeatedly detecting more of "0" and "1" for a specific bit of a key representing personal information is selected as the detection value.

The decoding apparatus compares the buyer discrimination signal with the buyer information stored in the buyer information DB 240 to identify who the buyer is and provides information about the buyer (S409).

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention but to describe the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

In addition, the terms "comprise", "comprise" or "having" described in the specification mean that a corresponding component may be included unless otherwise stated, and thus, other components are excluded. It should be construed that it may further include other components. All terms, including technical and scientific terms, have the same meanings as commonly understood by one of ordinary skill in the art unless otherwise defined. Terms used generally, such as terms defined in a dictionary, should be interpreted to coincide with the contextual meaning of the related art, and shall not be interpreted in an ideal or excessively formal sense unless explicitly defined in the present invention.

An embodiment of the present invention is applicable to an encoding apparatus, a driving method thereof, a decoding apparatus, and a driving method thereof. At the same time, buyer information can be extracted from the leaked video while eliminating high computational load. In addition, the watermarking method of inserting a watermark directly on the original image can be applied to extract the watermark even after editing and recompressing the video.

100: watermarking module 110: video encoding unit
111: first encoding unit 113: second encoding unit
120: buyer video generation unit 121: personal information-based video generation unit
123 and 240: buyer information DB 200: frame division
210: decoding unit 220: watermark detection unit
230: buyer information generating unit

Claims (10)

A watermarking module for generating and outputting a watermark embedded video by embedding the watermark in the video;
A video encoding unit for dividing and encoding the video without the watermark into an arbitrary frame group, receiving the watermark embedded video, and dividing and encoding the watermark embedded video in the same manner as the arbitrary frame group; And
A personal information-based video generation unit for generating and outputting a personal information based video by selecting one of an arbitrary frame group of the video without the watermark and an arbitrary frame group of the watermark embedded video according to the purchaser information.
And a video encoding device. The method of claim 1,
The arbitrary group is characterized in that when the video encoding unit is compressed in the order of "IBBPBBPBBPBB ... ... P", the video encoding apparatus, characterized in that I and P, or between P and P frame is divided into one frame group . The method of claim 1,
And the number of the arbitrary frame groups and the purchaser information is the same. The method of claim 1,
The personal information-based video generation unit is linked to the buyer information DB,
The buyer information DB stores the buyer information and provides the buyer information according to a request of the personal information-based video generation unit. The method of claim 1,
The personal information-based video generation unit selects one frame group from any frame group of the watermark embedded video when the buyer information is "0".
And when the purchaser information is "1", selecting one frame group from any frame group of the input video to generate the privacy-based video. A frame dividing unit for receiving a personal information-based video formed by combining a watermark-inserted frame group and the watermark-uninserted frame group, and dividing the received personal information-based video into an arbitrary frame group;
A decoding unit for decoding the divided arbitrary frame group;
A watermark detector for determining whether a watermark is detected in each of the decoded arbitrary frame groups, and outputting different detection signals according to whether the watermark is detected; And
Buyer information generation unit for comparing the buyer information stored in the memory and the buyer identification signal formed by combining the detection signal to confirm the buyer, and outputs the information on the confirmed buyer
Video decoding apparatus comprising a. The method of claim 6,
The watermark detection unit outputs a detection signal of "0" when the watermark is detected in each of the arbitrary frames, and outputs a detection signal of "1" when the watermark is not detected. . The method of claim 6,
The buyer information generation unit is linked to the buyer information DB,
The buyer information DB stores the buyer information and provides the same according to a request of the buyer information generator. Embedding a watermark in the video to generate and output a watermark embedded video;
Dividing and encoding the video having no watermark embedded into an arbitrary frame group, receiving the watermark embedded video, and encoding the watermark embedded video by dividing the watermark embedded video in the same manner as the arbitrary frame group;
Generating and outputting a privacy-based video by selecting one of an arbitrary frame group of the non-watermark embedded video and an arbitrary frame group of the watermark embedded video according to the purchaser information;
And a video encoding method. Receiving a personal information based video formed by combining a watermark-inserted frame group and the watermark-uninserted frame group and dividing the received personal information-based video into an arbitrary frame group;
Decoding the video in the divided group of frames;
Determining whether a watermark is detected in each of the decoded arbitrary frame groups, and outputting different detection signals according to whether the watermark is detected; And
Comparing buyer information stored in a memory with buyer identification signals formed by combining the detection signal to identify the buyer and outputting information on the confirmed buyer;
Video decoding method comprising a.

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