摘要:
A method and system for compressing television video signals for digital transmission allows full motion pictures to be transmitted. The analog signal is digitized and stored in a memory (A) in consecutive pixel value locations. The values of the color components of each pixel value are summed and stored in a memory (B). In the second frame, the sum of each pixel value is compared with the sums stored in memory (B). If the difference is greater than a filter member, then that particular pixel is transmitted by the control computer (27). The total number transmitted for each frame is compared to a maximum allowable data rate, and the filter number is adjusted accordingly.
摘要:
A visible light communication system having a transmission apparatus for modulating a transmission signal to a multiple-value number and a reception apparatus for demodulating a multiple-value modulated transmission signal is provided. The transmission apparatus includes a plurality of light emitters for emitting light in different colors, a chromaticity coordinates calculator for mapping a digital value to a chromaticity coordinates value, and a light intensity controller for controlling a light intensity of each of the light emitters based on the chromaticity coordinates value corresponding to the digital value. The reception apparatus includes a plurality of light receivers having different spectral characteristics, a chromaticity coordinates calculator for calculating a chromaticity coordinates value according to a received light intensity detected by each of the light receivers, and a demodulator for demodulating the digital value from the chromaticity coordinates value.
摘要:
Für ein Verfahren zur Übertragung von Daten von einem digitalen Farbdekoder (1), welcher ein digitales Farb-Bildsignal dekodiert, zu einer anderen Signalverarbeitungseinheit (2), ist zur Vermeidung von Bildstörungen in der Signalverarbeitungseinheit vorgesehen, daß wenigstens ein erstes und ein zweites Digitalsignal von dem Dekoder (1) zu der Signalverarbeitungseinheit (2) seriell übertragen werden, daß das erste Digitalsignal vom Momentanwert einer im Dekoder (1) verwendeten Taktfrequenz abhängig ist, mit der das Digitalsignal in dem Dekoder (1) verarbeitet wird, und daß das zweite Digitalsignal vom Momentanwert einer im Dekoder (1) erzeugten Farb-Hilfsträgerfrequenz abhängig ist, die zur Farb-Dekodierung eingesetzt wird.
摘要:
A voltage controlled reference oscillator (20) with a high Q and narrow tunability bandwidth produces an output oscillator frequency which is frequency divided (18) by four alternative constants to produce four different clock frequencies for four different digital video standards, D1 component at 270 MHz, NTSC D2 composite at 143 MHz, PAL D2 composite at 177 MHz, and a proposed new composite video standard that is to operate at a 360 MHz clock rate. Automatic identification of which serial digital video is present is accomplished by having the clock generator (20,18) produce a clock signal at the frequency required by one of the video formats while a phase lock loop (90,26) attempts to lock onto the incoming signals at that frequency. If no lock occurs within a predetermined time interval, the clock generator (20,18) is made to produce a clock signal at the frequency required by a different one of the video formats and the phase lock (90,26) is attempted again. This is repeated until a lock is attained. Optionally, when a lock occurs, the video is tested (80) for validity within the format that is consistent with the clock frequency that produced the lock.
摘要:
La présente invention concerne un procédé de traitement d'un signal vidéo codé sous forme de blocs de k mots, ce signal étant écrit dans ou lu à partir de deux mémoires de trame (FM1,FM2) comportant chacune un port d'entrée, un port de sortie à vitesse rapide et un port de sortie à vitesse lente. D'après ce procédé, le signal vidéo numérique en entrée est formé par des ensembles de M′ blocs avec N′ blocs contenant des données de luminance (Y1, Y2,... ) et M′-N′ blocs contenant des données de chrominance (C1, C2,...), les blocs contenant les données de chrominance (C1) étant inscrits dans la première mémoire (FM1) et les blocs contenant les données de luminance (Y1) étant inscrits dans la deuxième mémoire (FM2), les mémoires étant inversées à chaque trame. Ensuite les blocs contenant les données de luminance et les blocs contenant les données de chrominance sont lus simultanément sur le port de sortie à vitesse rapide de chaque mémoire, les mémoires étant inversées à chaque trame, et les données sont éventuellement traitées de manière à obtenir en sortie des données vidéo présentant un rapport de compression de M/N avec M > N. Application à la télévision.
摘要:
A colour video signal processing apparatus supplied with luminance data (Y) and first and second colour difference data (I, Q), each being digitized at a first sampling frequency and formed by matrix calculations (4), wherein at least one of the first and second colour difference data (I, Q) is sampled (61, 6Q) at a second sampling frequency which is equal to the first sampling frequency divided by an integer, the band of the sampled output is limited to be a predetermined band by a digital filter (71, 7Q), and the luminance data (Y) and said first and second colour difference data (I, Q) whose bands have been limited are transmitted as recorded (10).
摘要:
A decoder-recoder arrangement (1) for decoding a composite digital television signal for recording on a digital video recorder (8) and for subsequently recoding the reproduced signal, the arrangement comprising a decoder (6) including filters (11, 15 and 16) for separating two chrominance components from the composite digital television signal, demodulators (17 and 18) for demodulating the chrominance components, sample rate reducers (19 and 24) for reducing the sample rates of the demodulated chrominance components, interpolators (21 and 26) for interpolating samples into the sample-reduced demodulated chrominance components to restore the sample rate to the original value,modulators (22 and 27) for remodulating the interpolated chrominance components an adder (23) for adding together the modulated interpolated chrominance components, and a subtractor (13) for subtracting the output of the adder (23) from the input composite digital television signal; and a recoder (7) including interpolators (32 and 35) for interpolating samples into said sample-reduced demodulated chrominance components to restore the sample rate to the original sample value, modulators (33 and 36) for modulating the interpolated chrominance components obtained from the interpolators (32 and 35), an adder (34) for adding together the outputs of the modulators (33 and 36), and an adder (30) for adding the output of the adder (34) to the output of the subtractor (13) to derive the original composite digital television signal.
摘要:
In a cable television system, a specific carrier is assigned to deliver programming content of a program channel to a service area for a period, defined as a function of viewership of the program channel during that period. For example, the program channel is assigned the specific carrier during the time when it has a generally strong viewership. Otherwise, the program channel is assigned a carrier on an as needed basis, i.e., only when one or more subscribers in the service area request such a program channel. Viewing statistics are generated to identify viewership patterns or viewing habits of the subscribers in the service area with respect to a given program channel. In another embodiment, based on the viewing statistics, popular and unpopular programs, program elements, program lineups, program channels are identified on a temporal and/or regional basis.