Abstract: A method and apparatus for preventing unauthorized use of DVDs on a DVD ROM drive. The method comprises a DVD disc that includes special data processing. When the DVD is replayed on a standard DVD ROM drive the invention causes the output of the DVD ROM drive to be erroneous, such that the computer cannot use the data. According to the invention, when encoding a disc, the error correction and/or error detection bits, check bytes, are moved into the normal or main data area. When this scrambled data is output from a standard DVD ROM drive, the data in the check byte area is lost and the information is not useable. For authorized use, this scrambling is reversed before sending video and/or audio data to the MPED decoder and AC-3 decoder respectively.

Abstract: The disclosure relates to a recording and reading apparatus constituting a kind of video reservoir in the home of the consumer. Thanks to a large-capacity storing technique with suitable technical means, broadcasters transmit numerous programs via specific channels and the consumer may control the content of his reservoir (by recording, reading and erasing programs). The invention is applicable to on-demand video in the consumer's home with a video reservoir constituting a video-library that is regularly updated by broadcasters and/or by the consumer himself.

Abstract: The invention relates to a method and device for obtaining an adaptive selection of sets of data stored in a mass memory. The method and device use administrative information stored in a administration memory and related to the data sets, and allow to obtain a classified list of data sets. The adaptive selection may reflect habits of access to the sets of data by a user as well as momentary preferences of the user.

Abstract: The invention relates to a method and a device for obtaining an adaptive selection of sets of data stored in a mass memory (30). The method and the device use administrative information stored in an administration memory (31) and related to the data sets, and allow to obtain a classified list of data sets. The adaptive selection may reflect habits of access to the sets of data by a user (35) as well as momentary preferences of this user. The data sets may for example be songs recorded on a magnetic tape (29).

Abstract: The invention relates to a method of access to data sets stored in a bulk memory. During an access time to a data set, the method provides for reading introduction data and exploiting these. This way the method overcomes the problem of long access times in a bulk memory. The method may notably be used when data sets are arranged sequentially on a sequential data carrier, which is for example the case for songs recorded on a magnetic tape. A device for implementing the method is also defined.

Abstract: An optical disc comprising two elementary discs glued to each other by a transparent glue layer. The first elementary disc comprises an information surface according to DVD standard and the second elementary disc comprises an information surface according to CD standard. The present optical disc may be read by a CD player for CD information and by a DVD player for DVD information. The problem of costs and other difficulties for ascending compatibility of DVD players is therefore solved while assuring a simple and smooth transition from CD discs to DVD discs for consumers.

Abstract: The invention relates to a method of access to data sets stored in a bulk memory. During an access time to a data set, the method provides for reading introduction data and exploiting these. This way the method overcomes the problem of long access times in a bulk memory. The method may notably be used when data sets are arranged sequentially on a sequential data carrier, which is for example the case for songs recorded on a magnetic tape. A device for implementing the method is also defined.

Abstract: The disclosure relates to a recording and reading apparatus constituting a kind of video reservoir in the home of the consumer. Thanks to a large-capacity storing technique with suitable technical means, broadcasters transmit numerous programs via specific channels and the consumer may control the content of his reservoir (by recording, reading and erasing programs). The invention is applicable to on-demand video in the consumer's home with a video reservoir constituting a video-library that is regularly updated by broadcasters and/or by the consumer himself.

Abstract: The disclosure relates to a recording and reading apparatus constituting a kind of video reservoir in the home of the consumer. Thanks to a large-capacity storing technique with suitable technical device, broadcasters transmit numerous programs via specific channels and the consumer may control the content of his reservoir (by recording, reading and erasing programs). The invention is applicable to on-demand video in the consumer's home with a video reservoir constituting a video-library that is regularly updated by broadcasters and/or by the consumer himself.

Abstract: A magnetic tape apparatus for the recording and reproduction of signals, including a magnetic tape having plural data tracks running parallel to an edge of the tape; a multi-track reading device including a multi-track playback head configured to read simultaneously plural of the tracks and output signals corresponding to data recorded on the plural tracks; and a housing in which the tape and the reading device are permanently disposed; wherein the tape is adapted for simultaneous recording of data onto plural data tracks of the tape via external recording heads upon the apparatus being connected to an external recording facility.

Abstract: A television camera and display device, in which a transmission and reception utilizes quincuncial scanning (HDQ) with sub-sampling associated with an optical filter (9) for reducing the diagonal resolution of the image. The filter (9) prevents the folding of the spectrum when subsampling is employed, and permits the simplification of the device. The device may be implemented in both solid-state and vacuum tube form. It is applicable especially to high-definition television having only a restricted pass band and low sampling frequencies, and to the acquisition of and to the visual display of images in HDQ mode.

Abstract: The obtaining of a geometrical effect, with an image, is done by a two-dimensional filter with variable characteristics controlled by a computer to compute the points of a pre-established conversion grid, superimposed on the image, as a function of neighboring points of the original image and of the desired effect. A memory contains the original image. Auxiliary images, obtained by successive reductions, in fixed proportion, of the original image, are stored and a point of the conversion grid is computed by selecting that of the memories for which the reduction factor enables the easiest computation while, at the same time, preserving the quality of the image.

Abstract: A method and a device for coding binary data to be transmitted and a device for decoding coded data dispense with the need to transmit a direct-current component and make it possible to reconstitute clock signals from coded data without any addition of a particular channel. With this objective, the input signal constituted by a sequence of groups of eight binary data is converted to a coded signal constituted by a sequence of words of sixteen binary data associated respectively with the groups and having a data repetition frequency which is double the repetition frequency of the input signal data. The words are also chosen so as to ensure that each datum of the coded signal is followed or preceded by a datum having the same logic state. Furthermore, a sequence of particular words is inserted at the beginning of the message in order to permit easy recovery of clock signals at the time of decoding.