Abstract: Systems and methods for authenticating a digital file are provided. The systems and methods may operate independently or supplement existing copy protection systems, such as CSS, and help make them more robust. The digital file may be stored on a computer readable medium such as a physical disc, digital content downloaded from the Internet, or any other suitable digital content. In some aspects, the systems and methods described herein include identifying media content stored in a digital file that needs to be authenticated, and subsequently reading suitably chosen media blocks in encrypted (and unencrypted) form from the digital file for comparison with corresponding blocks (e.g., stored in a database) obtained from a genuine copy. The digital file will be authenticated only in the case of a successful match.

Abstract: Recording data has content data and navigation control data to enable a legitimate player to navigate the content data. The recording data has a content data set and a spurious data set that is difficult to distinguish from the content data set but will ignored by a legitimate player. The content data is associated with the content data set and the spurious data set. The spurious data set may be associated with control data that inhibit playing or correct playing of the content data. A ghost structure such as a ghost video title set my be provided by causing information in at least one of the video title set information, video manager information and the volume information file structure to reference a non-existent video title set or not reference an existing video title set. The recording medium may be an optical disc such as a DVD or its precursors.

Abstract: Systems and methods for authenticating a digital file are provided. The systems and methods may operate independently or supplement existing copy protection systems, such as CSS, and help make them more robust. The digital file may be stored on a computer readable medium such as a physical disc, digital content downloaded from the Internet, or any other suitable digital content. In some aspects, the systems and methods described herein include identifying media content stored in a digital file that needs to be authenticated, and subsequently reading suitably chosen media blocks in encrypted (and unencrypted) form from the digital file for comparison with corresponding blocks (e.g., stored in a database) obtained from a genuine copy. The digital file will be authenticated only in the case of a successful match.

Abstract: Copying apparatus has a reader operable to access locations of a recording medium to read both content data and navigational command data that determines the order in which a player of the recording medium will access the content data. A navigator executes a navigation command in accordance with navigation data read by the reader. A controller controls the location of the recording medium accessed by the reader in accordance with the result of the execution of a navigation command executed by the navigator so as to cause the reader to follow a navigation path through the content data defined by the navigation data and to cause a presentation data storer to store data for enabling recording of the content data for the navigational path.

Abstract: Generally the more effective is the copy protection provided on an optical disc, such as a DVD, the greater is the likelihood that the copy protection will adversely interfere with legitimate uses of the optical disc. It is therefore proposed to include at least one region of subversive data within the content in the data area of an optical disc, and then to prevent access to each such region of subversive data during normal playback of the disc. For a DVD, the subversive data may be incorporated within video objects and/or may be in gaps between files in the DVD_Video zone. It is arranged that there are no navigable paths to the regions of subversive data.

Abstract: Generally the more effective is the copy protection provided on an optical disc, such as a DVD, the greater is the likelihood that the copy protection will adversely interfere with legitimate uses of the optical disc. It is therefore proposed to include at least one region of subversive data within the content in the data area of an optical disc, and then to prevent access to each such region of subversive data during normal playback of the disc. For a DVD, the subversive data may be incorporated within video objects and/or may be in gaps between files in the DVD_Video zone. It is arranged that there are no navigable paths to the regions of subversive data.

Abstract: Subversive DSV (SDSV) sequences of data symbols having a large absolute value of DSV are extremely valuable in the copy protection of optical discs as they can induce uncorrectable read errors. However, very few SDSV sequences of data symbols can be found in multimodal codes such as Eight-to-Sixteen Modulation (ESM) utilised in DVDs. It is required to select data symbols, for encoding using a multimodal code, which are capable of forcing an encoder to produce at least one subversive sequence of code words. A possible code word for a data symbol is selected if the code word has a large absolute value of DSV and there are no alternative code words, or all alternative code words are equivalent, or all alternatives except one are ruled out by RLL rules.

Abstract: The invention provides a device driver for monitoring and controlling access to data on a computer readable medium. The device driver comprises an interface for access to a device-driver stack for a media drive, a detector for detecting the insertion of a computer readable medium in said media drive, and a monitor for monitoring data transfer from said computer readable medium. The monitor evaluates a behavior characteristic of an application accessing data on said computer readable medium, and indicates when said behavior characteristic fulfills predetermined criteria. A control system is responsive to said monitor for issuing at least one control output when said behavior characteristic fulfills said predetermined criteria. The invention also provides a method of monitoring and controlling access to data on a computer readable medium by means of the device driver.

Abstract: The more effective is the copy protection provided on a DVD, the greater is the likelihood that the copy protection will adversely interfere with legitimate uses of the disc. In a disc where the content is arranged in physical sectors, it is now proposed to provide subversive regions on the disc having a similar structure to genuine regions. A subversive region and a genuine region will each extend over one or more physical sectors. The subversive region will be provided with physical sector addresses which coincide with addresses of the genuine region. Navigational data will ensure that it is the genuine, rather than the subversive, region which will be accessed during normal play, but the subversive region will effectively hide the genuine region during copying.

Abstract: Subservive data has been incorporated in the content of an optical disc, such as a DVD, to prevent copying of the disc. To defeat such copy protection, devices to copy optical discs are now being controlled to only copy data referred to by selected program paths. Accordingly, it is proposed to provide copy protection for optical discs by introducing errors into redundant control data to frustrate access to content on the disc. For example, the errors may be inconsistencies in a Video Manage Information Table (VMGI) or in a Video Title Set Information Table (VTSI).

Abstract: To copy protect an optical disc, such as a DVD, program chains additional to the main program chain are provided. These program chains may lead to the genuine data but in an incomplete or incorrect order or to false data. Sufficient additional program chains are provided to make it difficult to identify the main program chain amongst all of the program chains provided on the disc. The structure of the further program chains ape that of the main program, again to hide the main program chain. The navigation path which leads to the main program chain, and hence to the content on the DVD, is dynamically generated and at least some of the information required to generate the navigational path arises by setting parameters associated with a player or with a user. Thus a search of all of the navigation information on the disc will fail to reveal the navigation path to the content.

Abstract: Recording data to be recorded on an optical disc such as a DVD has at least one video title set having content data files having a video object data set, a video title set information file for the video title set and video manager information. The recording data also has a volume file system information having data relating to file identification for enabling location of content data files. In order to inhibit copying by a file-by-file copying apparatus data relating to file identification in the volume information for at least one of the content data files is caused to be incorrect, for example altered The incorrect information may be at least one of a file start address, a file length, incorrect error detection data, a pointer to a corrupt video title set information file rather than the correct video title set information file.

Abstract: The more effective is the copy protection provided on a DVD, the greater is the likelihood that the copy protection will adversely interfere with legitimate uses of the disc. In a disc where the content is arranged in physical sectors, it is now proposed to provide subversive regions on the disc having a similar structure to genuine regions. A subversive region and a genuine region will each extend over one or more physical sectors. The subversive region will be provided with physical sector addresses which coincide with addresses of the genuine region. Navigational data will ensure that it is the genuine, rather than the subversive, region which will be accessed during normal play, but the subversive region will effectively hide the genuine region during copying.

Abstract: Recording data has content data and navigation control data to enable a legitimate player to navigate the content data. The recording data has a content data set and a spurious data set that is difficult to distinguish from the content data set but will ignored by a legitimate player. The content data is associated with the content data set and the spurious data set. The spurious data set may be associated with control data that inhibit playing or correct playing of the content data. A ghost structure such as a ghost video title set my be provided by causing information in at least one of the video title set information, video manager information and the volume information file structure to reference a non-existent video title set or not reference an existing video title set. The recording medium may be an optical disc such as a DVD or its precursors.

Abstract: Copying apparatus has a reader operable to access locations of a recording medium to read both content data and navigational command data that determines the order in which a player of the recording medium will access the content data. A navigator executes a navigation command in accordance with navigation data read by the reader. A controller controls the location of the recording medium accessed by the reader in accordance with the result of the execution of a navigation command executed by the navigator so as to cause the reader to follow a navigation path through the content data defined by the navigation data and to cause a presentation data storer to store data for enabling recording of the content data for the navigational path.

Abstract: To copy protect an optical disc, such as a DVD, program chains additional to the main program chain are provided. These program chains may lead to the genuine data but in an incomplete or incorrect order or to false data. Sufficient additional program chains are provided to make it difficult to identify the main program chain amongst all of the program chains provided on the disc. The structure of the further program chains ape that of the main program, again to hide the main program chain. The navigation path which leads to the main program chain, and hence to the content on the DVD, is dynamically generated and at least some of the information required to generate the navigational path arises by setting parameters associated with a player or with a user. Thus a search of all of the navigation information on the disc will fail to reveal the navigation path to the content.