摘要:
In a television transmission system, an encoding circuit in a data generator transmits (or stores) identification information relating to variable numbers of television lines or variable portions of television lines in which luminance and chrominance information occur, compressed where appropriate. The data receiver includes a simple, properly adaptable decoding circuit which comprises presettable counters for counting portions of television lines and for counting television lines, outputs of these counters being coupled to address inputs of a programmable memory which is coupled to a multiplexer which is switchable by the identification information and is followed by a logic circuit for generating control signals for a chrominance memory having the same write and read rates and for luminance and chrominance memories having said write rates and several read rates, under the control of a clock pulse source which is switchable via the logic circuit and the identification information. In the data generator the encoding circuit may be of a similar construction combined with luminance and chrominance memories having different write rates and the read rate mentioned in the foregoing.
摘要:
A picture flicker correction is desired with video disc players involving display of a stop-motion or still television picture and with television displays using field and line frequency doubling, in accordance with the so-called ABAB method. With a movement detector (51) movement or the absence of movement is detected. Two adding circuits (19, 22) are connected in parallel to delay devices (9, 9+12) having time delays substantially equal to a field period. By means of two switch-over devices (32, 37) switched by the movement detector (51), the delay devices (9, 9+12) or the adding circuits (19, 22) can be coupled with a switch-over device (45) which is switched once per field period. A further delay device (42) having a time delay substantially equal to a field period provides for information transfer during second field periods of frame periods comprising two field periods. In the absence of movement detection, the original information is transferred, and in the event of movement detection, the combined information is transferred.
摘要:
Television transmission or data storage system with time-division multiplex encoding. At least two signal sources are coupled via an encoding circuit for time-division multiplex encoding to a transmission or storage channel to which a data receiver including a decoding circuit can be connected. The signal supplied comprises two or more sub-picture signals during the line periods and the signal-compression or expansion time ratios for the different sub-picture signals are different. The decoding circuit is suitable for consecutively supplying signals during a line period of the data receiver, which signals largely correspond to the different sub-picture signals.
摘要:
By providing, in a field-frequency doubling circuit comprising a converter circuit (3) of an A, A, B, B, type, an interpolation circuit (31) which combines, in an appropriate manner, the information of two subjacent lines of a first field of a picture of the television signal to be converted and a second field of a picture of the television signal to be converted, line flicker can be prevented from occurring without it being necessary to provide a movement detector and a change-over switch for an A, B, A, B-type conversion.
摘要:
Use is made of a digitally assisted DATV to effect a bandwidth reduction encoding and bandwidth reduction decoding, in addition to MAC-coding and MAC-decoding, of at least three picture signal channels (PC) each having a different picture signal refresh period equal to, for example, 80, 40 and 20 ms which are coupled via a time-division multiplex circuit (MUX). For with the diversity of picture signal sources, it was found that distinguishing during the picture signal processing between a film mode (SW1, T40) and a non-film mode (SW1, T20) results in a significantly improved high-definition picture resolution. This distinction is expressed at the DATV by one information bit (FM'). During the non-film mode (SW1, T20) three Y-liminance channels (PC11, PC13 and PC12) of 80, 40 and 20 ms and two U and V-chrominance channels (PC21 and PC22) of 80 and 20 ms are operative. During the film mode (SW11, T40) the Y-channels (PC11 and PC13) and the U and V-channels (PC21 and PC23) of 80 and 40 ms are only operative.
摘要:
A transmitting section of the system according to the invention has transmitting section signal paths for at least three classes of motion, each with a preprocessing circuit (143, 145 and 147) which are provided with means for individually sampling. These sampling means sample in accordance with separate sampling patterns so that each preprocessing circuit (143, 145 or 147) supplies a video signal which is suitable for a display with an optimum distribution of temporal and/or spatial resolution for the associated class of motion. Dependent on the class of motion determined, one of the preprocessing circuits (143, 145 or 147) is coupled to a channel (170). The video signal to be supplied to the channel (170) is therefore a video signal suitable for a display with an optimum distribution of temporal and/or spatial resolution for the given class of motion (FIG. 1A). A high-definition receiving section of the system according to the invention also has at least three receiving section signal paths comprising a postprocessing circuit (43, 45 and 47) which decodes a received video signl in accordance with a method associated with the relevant postprocessing circuit (43, 45 or 47). The correct postprocessing circuit (43, 45 or 47) is selected in accordance with the class of motion, so that in the receiving section of the system according to the invention a display with an increasing spatial resolution can be achieved in the case of a decreasing motion (FIG. 1B).
摘要:
In a receiver for extended television signals in which a wide aspect ratio picture and at least one horizontal bar are jointly coded so as to form a standard aspect ratio picture, the at least one horizontal bar conveys vertical resolution enhancement information, and the extended television signal receiver includes an arrangement (107,111) for modifying the vertical resolution enhancement information to reduce an amount of distortions comprised therein, and an arrangement for combining the wide aspect ratio picture and the modified vertical resolution enhancement information to provide an enhanced wide aspect ratio picture.
摘要:
Motion detection is based on picture signal value comparisons between picture elements (P) in consecutive, interlaced television pictures (n-2, n-1), (n, n+1), (n+2, N+3), motion or no motion, respectively, being determined in dependence on the fact whether comparison results exceed or do not exceed a threshold value. Changes in picture information between movie pictures (MP1, MP2, MP3) can negatively influence the telecine television motion detection if they make use of a preceding and a subsequent television picture. To prevent this, an instantaneous picture element (P1) in a first field (n) of a television picture (n, n+1) is compared with a number (P4, P5, P6, P7) of surrounding picture elements in a second field (n+1) and an instantaneous picture element (P11) in the second field N+1) is compared with a number (P14, P15, P16, P17) of surrounding picture elements in the first field (n).
摘要:
A television picture memory (MEM) containing digital picture signal values associated with picture elements (PIX) is coupled via a picture signal value comparison circuit (COM1) and an absolute value circuit (ABS1) to an adaptive threshold circuit (THR) for the picture signal differences. In order to obtain a motion detection with a directional sensitivity in the horizontal and vertical direction, the threshold circuit (THR) has an adaptive horizontal and vertical threshold value - adapting circuit (ADA) which produces the adaptive threshold values (HI and VI) via maximum value passing circuits (H MAX and V MAX) which are coupled to the memory (MEM) via an absolute value circuit (ABS2), a picture signal comparison circuit (COM2) and a signal combining circuit (AVE2), and by-passing it. The comparison circuit (COM2) is operative for the horizontal threshold value (HI) with picture elements in the line direction which are more or less adjacent to an instantaneous picture element and picture element values which are derived via the signal combining circuit (AVE2) from the picture elements of one of the more or less adjacent, superjacent or underlying lines belonging to the instantaneous, preceding or subsequent field period. The comparison circuit (COM2) is operative for the vertical threshold value (VI) with picture elements in the field direction that are more or less adjacent to the instantaneous picture element and picture element values which are derived via the combining circuit (AVE2) from the picture elements of one of the more of less adjacent, superjacent or underlying lines belonging to the instantaneous, preceding or subsequent field period.
摘要:
A receiver for a high definition television signal in which the signal prior to transmission is sub-sampled on a block-by-block basis according to the movement has an input (39) which receives the sub-sampled signal which is applied to a shuffler (40) which shuffles the pixels of blocks in a manner which is the inverse to that performed prior to transmission. The correctly positioned pixels are applied to means (43,44,45) for adaptive switched interpolation filtering capable of providing spatial frequency filter responses which approximate those at the transmitter, for sub-sampling blocks of the interpolated picture are sub-sampled but where pixels adjacent but outside a block are sub-sampled with the same structure as that of the block and for non-adaptive switched interpolation filtering for providing spatial frequency filter responses which substantially correspond to those at the transmitter. An output (46) provides the reproduced high definition television signal. A digitally assisted television signal at a further input 41 is used to control the inverse shuffling and the selection of filter responses.