Abstract: The invention principally relates to a device and to a method for writing in a storage device of the stack type. The invention relates to the use of stacks (1) of the first-in, first-out (FIFO) type for the unscrambling of television images. In order to be able to write in such a stack (1) starting from a desired address, the procedure begins with writing non-pertinent information in order to increment the stack's internal counter to which there is no access. Then, starting from the desired value of the counter, pertinent information is written. It is possible to rewrite pertinent information over the non-pertinent information placed for example at the start of the stack. The present invention applies in particular to the use of special memories for uses which have not been foreseen by the manufacturer. It applies more particularly to the use of stacks (1) of the first-in, first-out type for the unscrambling of television images.

Abstract: The device of the invention for a pay-television system comprises an emitter and several receivers using "smart cards". In addition to the unscrambling control signals, the emitter sends encrypted authentication messages to which a correct response can be given only by the receivers where valid cards are used.

Abstract: The present invention concerns a processing method for a video signal coded in the form of blocks of K words, this signal being written to or read from two frame memories (FM1, FM2) each including an input port, a high speed output port and a low speed output port. According to this method, the input digital video signal is formed by sets of M' blocks with N' block containing luminance data (Y1, Y2 . . . ) and M'-N' blocks containing chrominance data (C1, C2 . . . ), the blocks containing the chrominance data (C1) are written in the first memory (FM1) and the blocks containing luminance data (Y1) are written in the second memory (FM2). Then the blocks containing the luminance data and the blocks containing the chrominance data are read simultaneously on the high speed output port of each memory, the memories being inverted at each frame, and the data eventually being processed to obtain video data in output that presents a compression ratio M/N with M>N.

Abstract: A home computer system having a single input-output which is modified by a identifying circuit to identify a joystick or a mouse the identifying circuit utilizes potentiometers from the joystick which are connected to monostable circuits. The computer automatically recognizes that a joystick is present due to the triggering of the monostable circuits and the reading of the outputs from those monostable circuits.

Abstract: To counter illicit prevention of the invalidation of a smart card in a pay television network, for example when the period of validity for the card has expired, a verification of the card reader's ability to write to the card's memory is made. This verification consists in periodically sending a data item to be stored in the card. A counter on the card is reset by the writing voltage of the card's storage. In the event the writing voltage does not reach the counter, the counter's overflow output is connected to a read inhibition circuit which blocks functions of the card.

Abstract: In order to know, for the purpose of a response, the route taken by a message packet flowing in a transmission system having several different transmission channels, several fields (RA0 to RA2) are reserved in this message in which fields are entered the identities of the interfaces passed through by the message passing from one channel to another.

Abstract: In a network in which conflicts may arise because of simultaneous requests from several interlocutors, the invention provides for immediate granting of access to the network to a caller if, in a specified period of time prior to the request from the caller, no other request has been transmitted. If not, the controller of the network monitors the occupation of the network and, once it is no longer occupied, it verifies that no other request has been transmitted for a randomly specified period of time. If it is the case, it sends a verification message to the caller and, if it receives an acknowledgement of reception before a specified time, it grants him access to the network.

Abstract: A method for displaying a supplementary video image outside a main image. For example, the main image has a 4/3 aspect ratio and the tube has a 16/9 aspect ratio. The method includes steps of processing a supplementary video image at the time of the line return of the main image to provide a video signal of the desired format. Then, multiplexing the components of the main video signal with the components of the supplementary video signal; and then separately processing the components of the multiplexed signal to produce the components of the display signal for a display on the tube. The displayed image has the main 4/3 aspect ratio image in 4/3 aspect ratio occupying approximately 12/9 of the screen and supplementary video images occupying the remaining 4/9 of the screen.

Abstract: A device and to a method for generating control signals is set forth. The device according to the present invention allows the generation, from a single time reference, of the write control (WE) and read control (RE) signals for the information relating to a video line in a storage device (7, 8, 17, 18, 20). In this way, possible shifts between the synchronization of two successive lines due in particular to the transmission are overcome. The device according to the present invention is applied in particular to the generation, from a common time reference, of write signals and of read signals for a storage device (7, 8, 17, 18, 20) intended for storing a video image line.The invention applies principally to the production of devices for unscrambling scrambled television transmissions, particularly pay television transmissions.

Abstract: A method for linking data for recording on a recordable type of optical disk with data encoded according to a specific encoding using a CIRC type error correction system. The pieces of data are organized in frames, in blocks of p frames and in groups of n blocks. The frames of data and frames of sub-codes are synchronized by using pieces of information pre-recorded on the disk. During encoding, each group of n blocks receives and is preceded by three redundant blocks, namely a run-in block (RIN) itself preceded by a first dummy block (DMI) and second dummy block (DM2); and is follwed by two redundant blocks, namely a run-out block (ROUT) which is followed by a third dummy block (DM3). During writing on the disk, the length of the three redundant blocks is sufficient. They effectively set-up the record and reading of the data and its interleaving and error correction code. The disclosed method can be applied particularly to recordable optical compact disks.

Abstract: According to the disclosed method, a reference line is caused to be transmitted during the non-visible part of the image, the transmissions are received with a calibrated receiver, this reference line is sampled, an error signal is produced from the difference between this line and its theoretical value, a correction coefficient is deduced therefrom for each of the samples of the line, and this correction coefficient is applied to the lines of the following frames.

Abstract: The method of the invention consists, during the transmission of composite video signals, in the inclusion therein of series of access messages (ECM1, ECM2) and, during the unscrambling, carried out using a chip card reader whose chip card comprises encoded digital data, in using an interactive method of identification of a digital signature.

Abstract: According to the disclosed method, decoys which are the reproduction of the corresponding interpolated sequence are inserted into the scrambled line, at the end of the first section and at the start of the second section.

Abstract: The process of the invention concerns pay television networks with reinforced scrambling. To attract potential subscribers, the invention consists in cyclically transmitting non-scrambled images for brief periods, so that the type of program can be seen.

Abstract: Disclosed is a method for the processing of digital control data associated with an HD-MAC type video signal as well as a device for the implementation of the method. In this method, during one processing period, the digital control data associated with the video signal of the following processing period is decoded. The digital control data corresponding to n successing processing periods (n.gtoreq.2) is stored and then the data thus stored is decoded on a time sharing basis so as to achieve the output, in parallel, of the desired pieces of digital control data with their specific delay. Application to high-definition television.

Abstract: The disclosure pertains chiefly to an interface including an electrical supply. The disclosure concerns an interface capable of providing an external supply from the amplification of one of the signals. For example, the amplified DTR is used to give a supply voltage to a MIDI interface from an RS 232 serial interface using a nine-pin SUB D9M connector. The disclosure can be applied to the making of interfaces capable of giving an electrical supply to an external device as well as to computers including such interfaces. The disclosure can be applied chiefly to the making of computers capable of working under the MS-DOS operating system and capable of providing a supply voltage to the MIDI interface by means of an RS 232 serial interface and a SUB D9M connector.

Abstract: The method of the invention consists in shifting (a) the start of the scrambled section of a composite video line of a television image with respect to the start of the useful part of that line.

Abstract: To allow teleshopping to be performed quickly and reliably via the television network, receivers (3) are equipped with smart card readers (4), and the transmitter (2) sends information which is processed in the smart cards by means of the viewers' control devices (6). The result of this process is displayed on the screen and communicated later to the transmitter. This result allows the viewers' reactions to be authenticated.

Abstract: In order to register items of equipment brought into service in an apartment equipped with an HF transmission channel home-automation network, it is first verified that no other item of equipment from a foreign network is requesting registration (18), then a registration request standby signal (20) is transmitted and, following reception of the identity request signal (26) before the completion of a specified temporization (27), the requested identity is communicated to the item of equipment, else the procedure is aborted and subsequently recommenced.

Abstract: To prevent a person having found or stolen a card of a pay-television subscriber from using it fraudulently, the identity of the subscriber is recorded in a zone protected from reading and writing. At the beginning of the period of use of a new card, the new card compares the identity of the new card with that of the old one, and delivers the password only if the two identities are the same.