Victor Company of Japan, Limited

Naomichi Nishimoto

Yutaka Ichinoi

Akira Hirota

Tomoaki Suzuki

Takeo Murayama

Masahiro Hirasawa

Hiroshi Horii

Yoshihiko Ota

Takuya Tsushima

Takashi Uchimi

Yoshiteru Kosaka

Takeshi Okauchi

Koichi Kido

Susumu Kakuta

In a video signal recording apparatus, a first video signal is compressed into a second video signal in response to a controllable quantization factor which determines a degree of the compression. The quantization factor is controlled to maintain a data rate of the second video signal at substantially a constant rate. A detection is made as to a magnitude of the quantization factor. A decision is made as to whether or not the detected magnitude is greater than a predetermined reference magnitude. The second video signal is recorded on a recording medium when the detected magnitude is greater than the predetermined reference magnitude.

Video signal recording apparatus

A multi-cassette recording and reproducing apparatus includes at least one rack for storing a stack of tape cassettes and disk cassettes, the tape cassettes containing magnetic tapes, the disk cassettes containing disks; a tape drive unit for subjecting a magnetic tape of a tape cassette to information recording and reproducing processes; a disk drive unit for subjecting a disk of a disk cassette to information recording and reproducing processes; and a common cassette selecting and carrying mechanism for selecting one of the tape cassettes in the rack, for carrying the selected tape cassette between the rack and the tape drive unit, for selecting one of the disk cassettes in the rack, and for carrying the selected disk cassette between the rack and the disk drive unit.

Multi-cassette recording and reproducing apparatus

A magnetic tape is wound on a rotary drum through a predetermined angular range greater than a standard tape winding angle. The predetermined angular range has a first portion corresponding to the standard tape winding angle and a second portion extending outward of the first portion. A main information signal is recorded into a main information recording track on the magnetic tape which extends in a region corresponding to the first portion of the predetermined angular range. A sub information signal is recorded into a sub information recording track on the magnetic tape which extends along an extension line of the main information recording track and which extnds in a region corresponding to the second portion of the predetermined angular range. A plurality of magnetic heads have different track widths respectively and are mounted on the rotary drum. The magnetic heads form respective different tracks which together constitute the sub information recording track.

Magnetic video tape recording and reproducing apparatus

A control pulse recording circuit for a magnetic recording and reproducing apparatus comprises a control head, a circuit for detecting leading edges of control pulses reproduced by the control head, a circuit for generating a recording voltage having a polarity which changes at a time in accordance with recording data to be recorded in a re-write operation, and a switching circuit for blocking supply of the recording voltage to the control head at a time which is after a predetermined time from a time when the re-writing operation is ended and is immediately before a next leading edge of the control pulses.

Control pulse recording circuit for magnetic recording and reproducing

In an apparatus for time-compression video recording and time-expansion reproduction, first and second memory address counters are initialized in response to there being a simultaneous presence of vertical and horizontal sync pulses. Until the next vertical blanking period the counters are continuously incremented at different rates during mutually exclusive times for successively writing and reading the luminance component of a composite color television signal. A third memory address counter operable in recyclically variable count modes is provided for writing and reading the color-difference components at sequentially varying rates during a count cycle and generating an output pulse at the end of the count cycle. A phase comparator detects the phase difference between the horizontal sync pulse and the output pulse of the third address counter. A variable frequency oscillator is responsive to the phase difference for incrementing the third address counter at a rate corresponding to the phase difference.

Jitter-immune time expansion for time-compressed line-sequential video

A synchronizing signal separating circuit comprises an input terminal for receiving a composite color video signal to be recorded at the time of a recording, and for receiving a time-division-multiplexed signal at the time of a reproduction, a measuring circuit for measuring a time interval between a time when a horizontal synchronizing signal within an input signal received through the input terminal assumes a first predetermined value and a time when the horizontal synchronizing signal assumes a second predetermined value, a memory circuit having various correcting data pre-stored therein, for producing one correcting data in accordance with the time interval measured by the measuring circuit, and a signal generating circuit for generating the separated horizontal synchronizing signal at a time position in accordance with the one correcting data which is produced from the memory circuit. The various correcting data are pre-stored in the memory circuit for each of various time intervals required for the horizontal synchronizing signal to reach the second predetermined value from the first predetermined value, and contain data for constantly generating a separated horizontal synchronizing signal at a time position which is approximately constant in each of the various time intervals.

Synchronized signal separating circuit for a recording and reproducing

A video signal recording and reproducing apparatus comprises a circuit for generating a first signal having a sampling frequency f.sub.s which is approximately a natural number multiple of a horizontal scanning frequency f.sub.H of an input composite video signal and satisfies f.sub.s .apprxeq.f.sub.L +f.sub.U and having a phase which differs by 180.degree. for every one field, where f.sub.L represents a constant frequency in the range of 0.5 to 1 MHz and f.sub.U represents an upper limit frequency of a band required for a reproduced composite video signal, a circuit for sampling a signal part of the input composite video signal at least excluding synchronizing signal intervals thereof by the first signal, a circuit for recording and reproducing the sampled signal on and from a recording medium, a circuit for obtaining from the reproduced signal first and second reproduced sampled signals having a mutual time difference of one field, a circuit for generating from the reproduced signal a second signal having the frequency f.sub.s and having a phase which differs by 180.degree. for every one field, and a circuit supplied with the second signal for alternately and selectively passing the first and second reproduced sampled signals for every 1/2 period of the second signal so as to obtain a reproduced composite video signal which has been re-sampled.

Video signal recording and reproducing apparatus

A color video signal transmitting apparatus comprises first and second input terminals supplied in parallel with a time base compressed luminance signal and a first time base compressed line-sequential color difference signal which are obtained from one or a plurality of pickup elements of a television camera by changing an effective horizontal scanning period of the one or a plurality of pickup elements to a predetermined short period, a circuit for producing a second time base compressed line-sequential color difference signal by time base compressing the signal from the second input terminal, a circuit for obtaining a multiplexed signal of a second synchronizing signal having a predetermined width and being in phase with a first synchronizing signal from a third input terminal and a discriminating signal of every two regular horizontal scanning periods which is used to discriminate either one of two kinds of time base compressed color difference signals which make up the second time base compressed line-sequential color difference signal, to produce a multiplexed signal in which the second synchronizing signal and the discriminating signal are multiplexed, a circuit for obtaining a time-division-multiplexed signal by time-division-multiplexing the time base compressed color difference signals, the time base compressed luminance signal, and the multiplexed signal, and a circuit for transmitting the time-division-multiplexed signal to a transmitting path.

Color video signal transmitting apparatus

A recording signal generation system for a color video signal which is suitable for high density recording in a magnetic recording and playback apparatus. In each horizontal scan period which includes an effective horizontal scan period and a horizontal blanking period arranged serially on the time axis, a luminance signal is positioned in the effective horizontal scan period while, in the horizontal blanking period, compressed color signals generated by time-axis compressing color signals having a duration equal to the effective horizontal scan period by a predetermined ratio are disposed. The luminance signal and compressed color signals are time-division multiplexed. Special burst pilot signals are superposed on the multiplex signal each of which is separable from the compressed color signals and alternate with the other at an interval of one horizontal scan period, thereby discriminating the color signals from each other while indicating a position of horizontal blanking period. A carrier having a suitable frequency is frequency modulated by the superposed signal and the modulated output is used as a recording signal.

Recording signal generation system for color video signal

A video signal dropout compensation circuit is provided in a reproducing apparatus which reproduces a recorded signal from a recording medium recorded with a time-division-multiplexed signal which has been frequency modulated. The apparatus frequency-demodulates a reproduced frequency modulated time-division-multiplexed signal in a demodulator, and time base expands a time base compressed line-sequential color difference signal and a time base compressed luminance signal within a reproduced time-division-mulitplexed signal back to an original time base to obtain a reproduced line-sequential color difference signal and a reproduced luminance signal. The compensation circuit comprises a detecting circuit for producing a dropout detection signal when the reproduced frequency modulated time-division-multiplexed signal assumes a level smaller than a preset level, a switching circuit controlled in response to an output signal of the detecting circuit, and a delay circuit for delaying an output signal of the switching circuit by a delay time of two horizontal scanning periods. The switching circuit selectively supplies to the demodulator and the delay circuit the reproduced frequency modulated time-division-multiplexed signal while the dropout detection signal is not produced from the detecting circuit, and the output signal of the delay circuit while the detecting circuit produces the dropout detection signal.

Video signal dropout compensation circuit

A color video signal recording and reproducing apparatus comprises a circuit for separating a luminance signal and a carrier chrominance signal from a color video signal, a first compressing circuit for time base compressing the luminance signal by use of a RAM, a second compressing circuit for time base compressing a line-sequential color difference signal obtained from the carrier chrominance signal by use of a RAM, a circuit for producing a discriminating signal, a circuit for time-division-multiplexing signals obtained by subjecting output digital signals of the first and second compressing circuits to a digital-to-analog conversion and the discriminating signal to produce a time-division-multiplexed signal, a circuit for recording the time-division-multiplexed signal on a recording medium and reproducing the recorded signal to obtain a reproduced time-division-multiplexed signal, first expanding circuit for obtaining a digital luminance signal in an original time base by use of a RAM from the reproduced time-division-multiplexed signal, a second expanding circuit for obtaining a digital line-sequential color difference signal in an original time base by use of a RAM from the reproduced time-division-multiplexed signal, and a circuit for obtaining a reproduced luminance signal and a reproduced line-sequential color difference signal by subjecting the output digital signals of the first and second expanding circuits to a digital-to-analog conversion.

Color video signal recording and reproducing apparatus

Synchronizing signal separating circuit for a recording and reproducing

A clock pulse generating circuit in a color video signal reproducing apparatus comprises a first PLL supplied with a horizontal synchronizing signal within a time-division-multiplexed signal reproduced from a recording medium and having a response characteristic such that the first PLL can sufficiently follow a time base deviation in the horizontal synchronizing signal, a second PLL supplied with the horizontal synchronizing signal and having a response characteristic such that the second PLL substantially does not follow a time base deviation or noise in the horizontal synchronizing signal, a circuit for resetting a variable frequency oscillator within the first PLL by a reset signal, where the reset signal is obtained by tapping a signal which is subjected to a phase comparison with the horizontal synchronizing signal in a phase comparator within the second PLL, and a switching circuit for producing a write-in clock pulse from a pulse which is obtained from the first PLL during a write-in operation of memory circuits within first and second time base expanding circuit of the reproducing apparatus and for producing a read-out clock pulse from a pulse which is obtained from the second PLL during a read-out operation of the memory circuits within the first and second time base expanding circuit.

Growing community of inventors

Tokyo, Japan

Naomichi Nishimoto