Nippon Electric Co., Ltd.

Nec Corporation

Tokyo Broadcasting System, Inc.

Kazuo Kashigi

Masao Inaba

Akihiro Takahashi

Toshitake Kouyama

Mikio Shimizu

Masashi Onosato

Atsumi Sugimoto

Keiichi Hirayama

Takaya Morita

Hideo Makita

Shigeru Miyahara

Toshitake Koyama

Tomoo Tama

Takashi Tachibana

Transmitting and receiving apparatus, for transmitting an input video signal having 525 lines/field progressive scanning by converting the input video signal into a signal compatible with the NTSC system, and for reproducing from that NTSC-compatible signal a video signal having 525 lines/field progressive scanning. The transmitting apparatus has a first separating system for separating vertical high frequency components in a three-dimensional horizontal-vertical-temporal domain from the input video signal; a modulating system for modulating the separated components from the first separating system by .mu.-modulation; a system for filtering a modulation output from the modulating system to remove a lower sideband component from the modulation output, the filtering system having a Nyquist characteristic; and a system for multiplexing a filtered output from the filtering system to form the NTSC-compatible signal. The receiving apparatus has a second separating system for separating the multiplexed filtered output from the NTSC-compatible signal; and a system for reproducing a video signal having 525 lines/field progressive scanning in response to the filtered output from the second separating system. More particularly, the vertical high-frequency components have a vertical spatial frequency of 515/4 cph, and the filtered output from the filtering system has a frequency band of 2.2 MHz to 4.2 MHz.

Apparatus for transmitting an extended definition TV signal having

A circuit for processing television signals to produce special effects includes a special effects circuit and a key signal generating circuit. Instead of generating the key signal separately and tailoring it for the desired special effects by using complicated circuits, the key signal is superimposed onto a video signal to produce a composite video signal which signal is processed to conform to the desired special effects. After the processing, the key signal is separated from the composite video signal to be used as it is intended. Thus, complicated and dedicated circuits solely for use for processing the key signal are eliminated.

Special video effect system

On achieving a special effect on a television screen, a succession of picture elements is supplied to a video memory device comprising a plurality of memory units which are periodically and successively loaded with the picture elements by a write-in controller during a write-in operation and which are simultaneously accessed by a read-out controller to concurrently read a plurality of the picture elements out of the memory units, respectively. The write-in controller indicates a memory address numbered in common to the memory units until consecutive ones of the picture elements are delivered to all of the memory units and, thereafter, changes the address to another one. The read-out controller simultaneously delivers either a set of common-numbered memory addresses to the respective memory units or a set of the common-numbered memory addresses and adjacent memory addresses to the common-numbered addresses.

Video memory device capable of simultaneously reading a plurality of

A television video signal storage apparatus for storing an NTSC digital chrominance signal so as to facilitate further processing thereof. The signal is sampled at a sampling frequency 2n times the subcarrier frequency, whereby it contains 2n data for each cycle of the subcarrier, of which n data are a first polarity portion and n data are an opposite polarity portion. The apparatus includes a first inverter for inverting the polarity of n successive data corresponding to the opposite polarity portion of the digital chrominance signal, such that all of said 2n data have the same polarity; a memory for storing the modified signal; and a second polarity inverter for inverting the polarity of the n successive data corresponding to the opposite polarity portion of the modified signal as it is read out of the memory. Thus, the signal read out of the memory corresponds to the input digital chrominance signal. The digital chrominance signal may be provided by a Y/C separator which also provides a luminance signal, the latter being stored in a separate memory. In this case, the two memories may be controlled commonly by a single address generator or may be commonly controlled by separate writing address and reading address generators. The first and second polarity inverters may be controlled for reading data into and out of the chrominance signal memory with the same phase or with different phase.

Video signal storage apparatus for NTSC system

A scrambling apparatus which scrambles a television signal prior to its transmission to prevent interception of the signal by means other than a counterpart descrambler apparatus. The television signal is scrambled by dividing each scan line (a scan line includes its leading sync portion) into first and second portions which are divided by an intermediate picture element. Each line is transmitted as follows: first the intermediate picture element is transmitted followed by the second scan line portion, followed by the first portion which begins with the sync signal and is terminated by retransmission of the intermediate picture element. The position of the intermediate picture element is randomly changed in each successive scan line so that reconstruction of the original television signal becomes exceedingly difficult. In the descrambler (receiver), a random address generator which includes a read only memory which contains the sequence of the position of the intermediate picture element in successive scan lines is used for receiving the scrambled television signal and descrambling the signal and restoring it to its original form for use in standard television receivers.

Television signal scrambling apparatus

A PAL digital video signal processing arrangement includes converter circuitry for sampling a system video signal in response to sampling pulses having sampling points associated with .+-.U and .+-.V modulation axes on a color vector plane to convert an analog composite video signal containing a luminance signal and a color subcarrier into a digital video signal, and a modulation axis inverting configuration for inverting the polarity of the digitized color subcarrier at the sampling points associated with the .+-.V axis.

PAL digital video signal processing arrangement

A tracking system for producing special effects in a television picture by inserting a second television picture into a first television picture. The first and second pictures are represented by first and second video signals. A key signal representing a key frame to be positioned on the first picture is produced and the electrical noise is removed from the key signal. A position signal having two horizontal position signal values and two vertical position signal values is produced and represents the position of a circumscribed frame of the key frame. A compressed second video signal representing a compressed second picture is produced in response to the second video signal and the position signals. The horizontal and vertical position signals produce a frame signal, and the frame signal is applied to the noise removing circuitry. In response to the key signal the first video signal and the second video signal are combined to produce the special effects.

Digital video effects system employing a chroma-key tracking technique

A digital television video signal storage system wherein the required memory capacity is reduced and memory utilization efficiency increased by reducing the number of bits in an imaginary vertical memory address without effectively increasing the number of bits in an imaginary horizontal address.

Digital television video signal storage system

In a digital video effect system, only one one-frame RAM (30) produces a mixed and phase-locked signal (14) for n individually synchronized input television signals (11, 12) when read by horizontal and vertical address signals (48, 49) derived from a reference timing signal (15) in synchronism with horizontal and vertical synchronizing pulses included therein. Digital video signals (39') and vertical address signals (29') derived from n or (n-1) input television signal or signals are written in n or (n-1) four-line RAM (80) by horizontal address signals (28') derived also therefrom and read by horizontal address signals (48 or 28) derived either from the timing signal or one of the n input television signals. Thus horizontally phase-locked digital video signals (39, 83) are written in the one-frame RAM by the last-mentioned horizontal address signals and likewise horizontally phase-locked vertical address signals (29, 84).

Digital video effect system comprising only one memory of a conventional

Luminance/chrominance separating apparatus in which a luminance signal and chrominance signal are extracted from a composite color television signal by a comb filter. A low frequency signal component is extracted from the chrominance signal and passed through a variable attenuator. The low frequency signal component from the variable attenuator is added to the luminance signal to produce a compensated luminance signal.

Luminance/chrominance separating apparatus having a spatial filtering

In an electronic special video effect device, first and second digital video signals (D.sub.F and D.sub.S) derived during a keying interval of time from two television signals (VA and VB) between the beginning and a switching instant of each predetermined period and between the switching instant and the end of the period, respectively, are written in a memory (35) in addresses corresponding to the respective periods starting at an initial address corresponding to the switching instant. Each period may be a horizontal or a vertical scanning period. The memory addresses are merely cyclically read out to provide an output signal (VD) that enables a scene represented by one of the television signals to be pushed away from a television screen by another scene represented by the other, leftwards, rightwards, downwards, or upwards. Read-out may be started at the initial address with write-in carried out merely cyclically. Both may start at the initial address.

Special effect device for electronically accomplishing a gradual scene

A chroma-key tracking system for electronically compressing a television picture to predetermined dimensions and for moving the compressed picture to a specified area on the television screen where the compressed picture is inserted into a second picture present on the screen. The chroma-key tracking system advantageously operates in the presence of electrical noise associated with the chroma-key tracking signal.

A chroma-key insertion technique by which a part of a second television picture, designated by a chroma-key signal produced from a first television picture, is inserted into the first television picture. The second television picture is displayed on a television monitor which is inserted into the chroma-key frame advantageously allowing a television announcer to always face or direct his eyes toward the chroma-key screen in which a picture from a remote video source is to be inserted on a resultant picture.

A chroma-key tracking system for electronically compressing a television picture to predetermined dimensions and for moving the compressed picture to a specified area on the television screen where the compressed picture is inserted into a second picture present on the screen. The invention advantageously monitors the aspect ratio (the ratio of width to height of a picture frame) of the compressed picture and ensures that the compressed and inserted picture maintains a prescribed standard aspect ratio.

A phase locking system locks at least one incoming composite video signal to the synchronizing signals of a second, reference wave. The incoming signal is strobed at a rate dependent upon the incoming color subcarrier into a memory, essentially on a field-by-field basis. Circuitry is provided by grouping the fields on a repeating field-tagged basis (groups of four for the NTSC signal format) to maintain signal integrity.

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Tokyo, Japan

Kazuo Kashigi