Abstract: Disclosed is a watermark embedding method. The method includes receiving an original image, generating a watermark image based on the selected watermark pattern, generating an alpha blended stego image by alpha blending the original image and the watermark image, and providing the alpha blended stego image, in which the watermark image is generated by considering at least one of allowable pixel value range and alpha value ? range of the watermark pattern applied to a first pixel of the original image, wherein the at least one of allowable pixel value range and alpha value ? range are determined by the difference of pixel value of the first pixel between the original image and the stego image by embedding the watermark pattern to the first pixel.

Abstract: Disclosed is an apparatus for protecting a copyright of a 3D object model and method therefor, the apparatus including: a first module generating an original 3D object model by combining voxels in a 3D space of X, Y, and Z axes; a second module calculating voxel lengths of the axes and based on a voxel length of a longest axis among the lengths, the second module extending lengths of the remaining axes, thereby obtaining a 3D space area; a third module generating an obfuscation unique key; a fourth module generating at least one rotation axis position, rotation voxel range, and rotation frequency based on the key; and a fifth module axially rotating at least one voxel structure included in each rotation voxel range at a rotation angle by each rotation frequency to distort a shape of the model, thereby performing obfuscation. Accordingly, the copyright can be effectively protected.

Abstract: Provided are an apparatus and a method for detecting a scene cut frame. The apparatus and a method for detecting a scene cut frame includes an image selector configured to select input images by n image frames while shifting an input image at h frame intervals; a candidate frame detector configured to detect a candidate frame from the selected n image frames using at least one of a plurality of codecs and a plurality of scene cut detecting algorithms; and a final frame detector configured to detect a frame having a count value higher than a threshold value as a final scene cut frame by performing histogram analysis based on the detected candidate frame, wherein the h and the n are a real number greater than zero and the h is smaller than the n.

Abstract: A method, apparatus and system for protecting content based on an open license is disclosed. The method for protecting content based on an open license performed by a content protecting device may include receiving content from a user terminal; selecting an open license corresponding to the received content; analyzing a plurality of license authority items corresponding to the selected open license; storing license data including a value of the plurality of license authority items which is analyzed in a database with being linked with a unique identifier of the content; generating a Digital Rights Management (DRM) authority matched to the open license based on the value of the plurality of license authority items which is analyzed; and requesting to encrypt the content based on the generated DRM authority to a DRM server. Accordingly, the copyright of the content can be easily protected.

Abstract: The present invention provides a method for creating an electronic document file comprising monitoring creation and changes of an electronic document file, receiving a policy file including document level set-up information and security policy, searching for words associated with business information from the text data retrieved from the electronic document file, computing an exposure score of the electronic document file based on the number of times for words associated with business information being searched and document level set-up information, assigning a document level to the electronic document file based on the exposure score, and inserting a watermark to text of the electronic document file to be displayed on the client device based on the user's personal information received from the server. Accordingly, leakage of business documents for electronic document files including business information can be prevented by providing pre-security and post-security measures stronger than conventional measures.

Abstract: One aspect of the present invention discloses a watermark insertion method. The method includes: segmenting target text into pieces of page content; obtaining a watermark variable comprising a line alternation value indicative of a watermark mode changed for each line of the segmented page content and a watermark mode setting value; and applying a flip-flop component insertion algorithm for inserting a watermark into each of the pieces of segmented page content based on the obtained watermark variable.

Abstract: One aspect of the present invention discloses a device for content security. The device includes: an application execution unit configured to generate and control content in response to a content control command requested by a user; and a DRM agent configured to communicate with the application execution unit, to detect the content control command generated by the application execution unit, and to perform control on the content, and the DRM agent comprises a tracing module configured to insert security information into the content in order to prevent and trace content leakage.

Abstract: One aspect of the present invention discloses a client device for content security. The device includes: an application execution unit configured to control content in response to a content control command requested in a user level; a DRM agent configured to communicate with a DRM server and the application execution unit in the user level, to detect the content control command, to receive an encryption/decryption key and security policy for content from the DRM server, to provide the received encryption/decryption key and security policy to a client kernel module, and to transmit an encryption/decryption request; and the client kernel module configured to receive the encryption/decryption key and the security policy, to store the encryption/decryption key and security policy in a secure box of a kernel level, and to perform encryption or decryption on the content based on the encryption/decryption key and security policy in response to the encryption/decryption request.

Abstract: Provided are a method and apparatus for automatically splitting an object and a method, apparatus, and system for registering a file. The method for splitting an object includes receiving the data of a stereolithography (STL) file representing a 3D image, tagging vertex coordinates corresponding to objects included in the 3D image so that the vertex coordinates are classified for each object, and splitting each of the objects included in the 3D image based on the tagged vertex coordinates.

Abstract: Disclosed is a digital signature service system and method based on a hash function in which a main agent, who requires the generation of a digital signature, does not personally generate the digital signature, and wherein digital signatures may be simultaneously and stably generated for large-scale data such as multiple electronic documents and digital data using a hash function and a hash tree, which are known as a simple and secure method, to guarantee the integrity of the data in a digital signature-based structure based on a server.

Abstract: A method for transmitting contents including tracking information is described. The method comprising the steps of generating a content transmission stream relevant to an original content, determining at least part of the original content as a forensic mark (FM) target segment, generating a FM stream including the FM segment in which a particular pattern is inserted into the FM target segment and a FM stream different from the content transmission stream and transmitting the content transmission stream and the FM stream to a receiving device, wherein the FM stream is combined with the content transmission stream based on session information related to the transmitting in the receiving device.

Abstract: Disclosed is an authentication method using a TCP sync packet. The authentication method includes: generating, by a client, a Single Packet Authentication (SPA) packet (first step); sending, by the client, the SPA packet generated in the first step in a TCP sync packet to a server (second step); analyzing, by the server, the SPA packet included in the TCP sync packet to determine whether the SPA packet is valid (third step); and establishing a communication session between the server and the client by the server sending the TCP acknowledgment (ACK) packet to the client (fourth step).

Abstract: Disclosed are a system and method of a large-scale simultaneous digital signature service based on a hash function. According to the system and method, the main agent that requires the generation of a digital signature does not itself generate the digital signature, and digital signatures may be simultaneously and stably generated for large-scale data such as multiple electronic documents and digital data, using a hash function and a hash tree, which are known as a simple and secure method, to guarantee the integrity of the data in a digital signature-based structure based on multiple servers.

Abstract: Disclosed is a digital signature service system and method based on a hash function in which a main agent, who requires the generation of a digital signature, does not personally generate the digital signature, and wherein digital signatures may be simultaneously and stably generated for large-scale data such as multiple electronic documents and digital data using a hash function and a hash tree, which are known as a simple and secure method, to guarantee the integrity of the data in a digital signature-based structure based on a server.

Abstract: A content stream transmission apparatus with reverse traceability comprises a pattern insertion unit dividing the original content in units of segments and inserting at least two patterns to each segment and creating at least two pattern contents; an encryption unit encrypting the at least two pattern contents; a content selection unit selecting one of the at least two pattern contents based on user identification information; and a transmission unit transmitting the selected pattern content to a user device. Therefore, as copyright and leakage tracking information are enabled to be inserted into the contents in real-time, the present invention not only provides security-enhanced contents but also services real-time content streaming services.

Abstract: Disclosed are a method, apparatus, and system for controlling a terminal device. A method of controlling a terminal device is performed by a terminal device control unit included in the terminal device. The method may include determining whether or not to change a state of the terminal device into a terminal device control state based on range information including at least one of a control area and a control period in which the terminal device is controlled and the real-time information of the terminal device, changing the state of the terminal device into the terminal device control state based on a result of the determination, and controlling the terminal device based on the control information in the terminal device control state.

Abstract: There are disclosed a system and method for preventing the leaking of digital content. The system for preventing the leaking of digital content may include a digital content layer generation unit for generating a digital content layer displaying digital content, a security layer generation unit for generating a security layer including security information based on information about a user terminal, and an information display unit for displaying the security layer generated by the security layer generation unit and the digital content layer generated by the digital content layer generation unit in the display device of the user terminal in an overlapping form so that the security information looks like overlapping with the digital content. Accordingly, the illegal leaking of digital content through photographing or screen capture can be prevented.

Abstract: Disclosed are a method, apparatus, and system for controlling a terminal device. A method of controlling a terminal device is performed by a terminal device control unit included in the terminal device. The method may include determining whether or not to change a state of the terminal device into a terminal device control state based on range information including at least one of a control area and a control period in which the terminal device is controlled and the real-time information of the terminal device, changing the state of the terminal device into the terminal device control state based on a result of the determination, and controlling the terminal device based on the control information in the terminal device control state.

Abstract: A virtual application creating system comprises: a virtual environment library block including a plurality of modules that process native application program interfaces (APIs) of an operating system such that the native application APIs are suited to a virtual environment, finding a module capable of processing a specific native API from the plurality of modules when the specific native API is called and operating the found module; a virtual application installation block receiving position information of an application to be virtualized and information on an installation place where the application will be virtualized and installed from a user and inserting the virtual environment library block into a memory to install a virtual application in the installation place; and a virtual application execution block executing the virtual application installed in the installation place.

Abstract: Provided are a watermarking method and a watermarking apparatus for a mesh mode, which are applicable to a system which requires high precision, such as a rapid prototyping system. A reference coordinate system is set using 1-ring values of vertices of a 3D mesh model. The vertices are sorted based on the set reference coordinate system, and bit-information of the watermark consisting of bit string is, respectively, embedded into each of polygonal faces of the 3D mesh model in the sorted order. The present invention is advantageous in that the shape of the model is not deformed even when watermarked, and therefore the present invention is useful in a rapid prototyping system which requires high precision for the purpose of authenticating data integrity. The present invention can be also used for the purpose of marking contents without the need for storing, and for the purpose of information hiding.