Samsung Electronics Co., Ltd.

Jung W Ko

Christopher H Strolle

Allen LeRoy Limberg

Alvin R Balaban

Hermann J Weckenbrock

Werner F Wedam

Raymond A Schnitzler

Jong Kyung Yun

A magnetic tape recording with a new signal encoding format, apparatus for recording this format and reproducing apparatus for reproducing signals from this format. A standard VHS signal is recorded as a first set of parallel slant tracks having a predetermined spacing between each slant track. A high definition television signal is recorded in pairs of slant tracks of a second type that flank a slant track of the first type and are narrower in width than the slant track of the first type they flank. Additionally, the azimuth angle of the tracks of the first type alternates between different predetermined values for successive tracks, and the azimuth angle of the tracks of the second type differ both from the azimuth angle of the tracks of the first type which they flank, and from the azimuth angle of the tracks of the second type which are positioned next to them in the space between tracks of the first type. This format allows one tape to record both a high definition television signal and a standard VHS signal, which standard VHS signal can be played back using ordinary tape machines. Accordingly, this format provides a way to avoid the problem of having to carry a dual inventory of tapes in a tape sales or rental business.

Backward compatible HDTV recording/reproducing system

A high-resolution video tape recorder system is disclosed which is compatible with a conventional VHS format VTR and obtains an image signal for a high quality picture by double sampling a luminance signal component of the composite video signal and then separating those samples into first and second sub-Nyquist sampled luminance signal components interleaved in spatial phasing. These separated luminance signal components are respectively frequency-multiplexed together with opposite phases of color-under signal to be recorded on and played back from first and second parallel subtracks formed on the video tape within a standard track width.

High-resolution video tape recorder systems and methods for recording

A system for reproducing a luminance signal from a medium containing a previously recorded luminance signal with a high-frequency portion thereof compressed in dynamic range includes a circuit for recovering that luminance signal from the medium. Filtering is done to separate the low-frequency and compressed-in-dynamic-range high-frequency portions of the recovered luminance signal from each other. A corer responds to the separated compressed-in-dynamic-range high-frequency portion of the recovered luminance signal to provide a cored high-frequency portion with expanded dynamic range and reduced noise. The level of the cored high-frequency portion with expanded dynamic range and reduced noise is then boosted by a predetermined amount to compensate for energy losses during the compression of the dynamic range and added back to the low-frequency portion of the recovered luminance signal to reproduce a full-band luminance signal with at least partially restored dynamic range for high-frequencies and without readily visible high-frequency noise.

Deemphasis & Subsequent reemphasis of high-energy reversed-spectrum

A magnetic tape recording with a new signal-encoding format, apparatus for recording this format and reproducing apparatus for reproducing signals from this format. A standard VHS signal is recorded as a first set of parallel slant tracks having a predetermined space between each slant track. A high definition television signal is recorded in pairs of slant tracks of a second type that flank a slant track of first type and are narrower in width than the slant track of first type they flank. Additionally, the azimuth angle of the tracks of first type alternates between different predetermined values for successive tracks, and the azimuth angle of the tracks of second type differ both from the azimuth angle of the track of the first type they flank and from the azimuth angle of the tracks of second type which are positioned next to them in the space between the tracks of first type. This format allows one tape to record both a high-definition television signal and a standard VHS signal, which standard VHS signal can be played back using ordinary VHS tape machines. Accordingly, this format provides a way to avoid the problem of having to carry a dual inventory of tapes in a tape sales or rental business.

Deemphasis and subsequent reemphasis of high-energy reversed-spectrum

Horizontal and vertical peaking signals are separated from a video signal by combining variously delayed responses to the video signal. A cross-fader combines the separated horizontal and vertical peaking signals in proportions determined by a cross-fader control signal. A correlator responds to ones of the variously delayed responses to the video signal for generating an output signal representative of the relative degrees of vertical and horizontal correlation in the video signal. The correlator output signal addresses a read-only memory that supplies the cross-fader control signal. The adaptively generated peaking signal is suitable for adjustably peaking a luminance component extracted from the video signal, where that video signal is a composite signal also including a chrominance component. The extraction of the luminance component is preferably done on an adaptive basis, generating horizontal and vertical comb filter responses by suitably combining the variously delayed responses to the video signal and, with a further cross-fader, combining the horizontal and vertical comb filter responses in proportions determined by the cross-fader control signal.

Adaptive video peaking circuitry using cross-faders

A video recording/playback system includes in its recording electronics time-base correctors both for luma signal and for color-under signal, the time-base corrector for luma signal being used to facilitate comb filtering and the time-base corrector for chroma signal being used to maintain luma/chroma tracking during recording. The video recording/playback system includes in its playback electronics time-base correctors both for played-back luma signal and for played-back color-under signal, the time-base corrector for played-back luma signal being used to facilitate comb filtering and the time-base corrector for played-back chroma signal being used to maintain luma/chroma tracking during playback. With appropriate switching, the same pair of time-base correctors can be used in both the recording and the playback electronics of a video recording/playback system. A detector in the recording electronics determines when there is substantial time-base error in the video signal received for recording and conditions the comb filtering of the luma signal during recording to be carried out in just the spatial domain and not in the frame-to-frame time domain. The recording electronics includes circuitry for signaling the playback electronics, via a recorded signal, that the comb filtering of the luma signal during recording was carried out in just the spatial domain and not in the frame-to-frame time domain. The playback electronics responds to such signaling to adapt the comb filtering of the played-back luma signal to suit.

Time-base correction in a video recording/playback system

In each of various motion detectors operative on composite video signal comprising chrominance component signals as well as a luminance component signal, the chrominance component signals are suppressed with a filter that removes only diagonal high frequencies in the spatial-frequency domain. These diagonal high frequencies in the spatial-frequency domain include the chrominance signal components of the composite video signal if it is in accordance with an appropriate standard, such as that employed by broadcasters in the United States of America. Motion detection is improved by reason of including more of the spatial high-frequency components.

Video motion detector with full-band response except for diagonal

An apparatus and a method for reproducing television images from recordings of folded-spectrum video signals uses a zero-crossing detector to convert an FM signal encoding folded-spectrum luminance signal to a PPM signal having the folded-spectrum luminance signal in its baseband, accompanied by the harmonics of the FM carrier and their respective sidebands. The PPM signal is digitized by an analog-to-digital converter, after passage through an anti-aliasing filter that is used to suppress only higher frequencies that would otherwise be sampled at less than Nyquist rate during digitization. Except for this anti-aliasing filtering, the suppression of the harmonics of the FM carrier and their respective sidebands is deferred until after digitization. Linear-phase digital filtering is then used to suppress the harmonics of the FM carrier and their respective sidebands, and the folded-spectrum luminance signal supplied in response to this digital filtering is unfolded to restore it to its original full bandwidth. This procedure permits the group delay characteristic below the folding-carrier frequency to be kept constant, thereby avoiding phase error as would interfere with the unfolding of the folded signal into the original full bandwidth.

Linear-phase filtering for playback of recorded folded-spectrum video

A motion signal detection circuit adapted to a video recording/reproducing apparatus having a frequency unfolding circuit for unfolding a luminance signal of a high frequency component included in the luminance signal of a low frequency component into an original frequency band, comprising a prefilter for eliminating the folding carrier and sidebands thereof included in the video signal unfolded by the frequency unfolding circuit, a comb filter for filtering the output of the prefilter to detect a motion signal, an error compensation circuit for compensating the errors included in the motion signal output from the comb filter.

Motion signal detecting circuit

A video recorder for recording composite video signals includes an analog to digital converter for digitizing samples of the composite video signal being recorded. A sync separator separates horizontal synchronizing information from the composite video signal being recorded. Filtering separates the chrominance information portion of the composite video signal being recorded, and a down-converter mixes that separated chrominance information with a nervous carrier signal thereby to generate a color-under signal. A controlled oscillator generates a succession of pixel clock signals at a rate the frequency and phase of which are determined in accordance with an oscillator control signal, the rate being more than twice the frequency of the nervous carrier signal and setting the rate of the sampling by the analog to digital converter. A counter counts the number of pixel clock signals supplied by the controlled oscillator, and a frequency divider divides the count by a prescribed factor. A discriminator determines when the resulting submultiple of the count differs in frequency or phase from the horizontal synchronization separated from the composite video signal being recorded, to develop an error signal that is low-pass filtered to generate the oscillator control signal. This completes a phase-lock loop connection including the controlled oscillator, the counter, the frequency divider, the discriminator and the low-pass filter, which loop governs sampling during the analog to digital conversion of the composite video signal being recorded. The nervous carrier signal is derived from this same phase-lock loop.

Growing community of inventors

Lawrenceville, NJ, United States of America

Jung W Ko