Abstract: A digital video tape recorder ("VTR") that selects data useful for generating images during trick playback operation and records the data in trick play tape segments arranged on a tape to form fast scan tracks and multi-speed playback tracks. Each fast scan track comprises trick play tape segments located on a diagonal, relative to the length of the tape, of the same angle as the angle at which the heads of a VTR are expected to pass over the tape during trick play operation at a specific speed and direction of operation. Each multi-speed playback track comprises a plurality of trick play tape segments arranged parallel to the length of the tape. Data which is used for at least one mode of trick play operation is recorded in each trick play tape segment. Each fast scan track and multi-speed track crosses multiple normal play tracks.

Abstract: Methods of operating a digital video recording and playback device, such as a video tape recorder, to arrange trick play data into one or more groups, to generate error correction bits for each group of trick play data, e.g., a group of trick play data blocks, and to correct the data after being read back using the error correction bits is disclosed. The trick play data blocks are made to be smaller than normal play data blocks with multiple trick play data blocks being equal in size to a single normal play data block. By making a group of trick play data blocks equal in size to a single normal play data block, the group of trick play data blocks may be processed as a unit by the same error correction circuitry and in the same manner used to process individual normal play data blocks. In accordance with one embodiment, the error correction bits for a group of trick play data blocks are calculated treating the data in the group of trick play data blocks as a single unit.

Abstract: Digital video tape recorder apparatus that generates commands to instruct a television receiver to perform special processing, e.g., processing designed to enhance image quality, on video data received from the digital video tape recorder during trick play operation is disclosed. The commands from the video tape recorder inform the television receiver that the video tape recorder is operating in trick play mode and that video processing not performed on normal play video data output by the video tape recorder during normal play operation should be performed on the trick play video data which is output during trick play operation. The video data output during trick play operation is a subset of the normal play video data. The video processing commands output during trick play operation instruct a receiver to perform video processing intended to compensate for normal play data intentionally omitted by the video tape recorder from the trick play video data because of, e.g.

Abstract: A video recorder compatible receiver for receiving video data from a video recorder such as a video tape recorder ("VTR"). The receiver includes an error concealment circuit, a digital VTR port adapted for coupling to a VTR and/or a tuner module. The receiver receives digital video data from the VTR by either the digital VTR port or the tuner module. VTR commands may also be received from a VTR. Upon receiving a VTR command indicating that the VTR is operating in trick play mode or upon detecting video data that is indicative of VTR trick play operation, the error concealment circuit of the receiver disables normal play error concealment and enables trick play error concealment. The error concealment circuit may perform temporal and spatial filtering on the video data received from the VTR when trick play error concealment is enabled.

Abstract: In a television signal processing system of the type which encodes an auxiliary carrier modulated with auxiliary image information in line format, which carrier is placed within the spectral band of standard television signal components, and wherein the modulated auxiliary carrier tends to interfere with the standard television signal, the interference is minimized by spatially variably attenuating the auxiliary image information. The attenuation function is selected to apply greater attenuation to the auxiliary image information at the extremities of the lines than toward the center of the lines.

Abstract: Apparatus is disclosed for reducing unwanted jagged diagonal artifacts in a video signal. At an encoder, moving image information is intraframe averaged over a given frequency range, e.g., above 1.5 MHz, while still image information is subjected to a field repeat process over a given frequency range. At a decoder, still image information is subjected to a frame repeat process over the given field repeat frequency range, while moving image information is left unchanged.

Abstract: In a widescreen signal encoding system for a television-type signal, side panel chrominance information is conveyed in double sideband form on an auxiliary subcarrier having a field inverting phase relative to the phase of a standard chrominance subcarrier. Side panel high frequency luminance information exclusive of low frequency information also is conveyed on the auxiliary subcarrier, but in single sideband form. Illustratively the auxiliary subcarrier is at the 3.58 MHz frequency of the standard chrominance subcarrier.

Abstract: A television system for generating video signals for reception by a receiver having adaptive processing circuitry susceptible of errors includes circuitry for emulating portions of the receiver and detecting the occurrences of such errors. A signal representing the occurrences of the errors is generated and combined with the transmitted video signal. At the receiver the error signal is separated from the video signal and utilized by the adaptive processing circuitry to ameliorate the effects of such errors.

Abstract: A system for expanding/compressing a video signal includes a dual-port memory having read and write address inputs and a video signal input. A pixel counter provides a pixel location signal to the write address input of the dual-port memory, and to a programmed memory device (e.g., a PROM) including a look-up table. The memory device is programmed to provide a time expanded/compressed version of the pixel location signal in accordance with a programmed time expansion/compression factor, which is applied to the read address input of the dual-port memory. A time expanded/compressed video signal is developed at the output of the dual-port memory.

Abstract: A system for transmitting and receiving signals representing a high-definition television (HDTV) image is disclosed. The signals are sent over two conventional 6 MHz NTSC channels. A first signal, the main signal, is developed by encoding circuitry from HDTV source signals to be compatible with existing NTSC receivers in that it produces a display on those receivers which is not significantly distorted. The main signal includes psychophysically hidden video information which may be used by an extended definition receiver to produce a widescreen image having a higher level of detail than a conventional video image. A second signal, the auxiliary signal, is developed at the transmitter by decoding the main signal and subtracting the decoded main signal from the original HDTV source signals. The auxiliary signal, which includes frequency components from 0 Hz to 20 MHz is split into three bands, A (0 Hz-6MHz), B (6 MHz-12 MHz) and C (12 MHz-18 MHz).

Abstract: In a video signal expanding/compressing system including a video signal interpolator, video signals are peaked prior to interpolation. The amount of peaking is controlled in response to a signal representative of the distance between a pixel of an expanded/compressed video signal and a corresponding pixel of an original video signal.

Abstract: An NTSC compatible, single channel widescreen EDTV system encodes and decodes a television signal comprising (1) a main, standard format NTSC signal wth auxiliary low frequency side panel image information compressed into an overscan region thereof; (2) auxiliary high frequency side panel image information; and (3) auxiliary high frequency horizontal luminance information. High frequency components 2 and 3 are subjected to non-linear amplitude companding, with large amplitude compression at an encoder and inverse amplitude expansion at a decoder.

Abstract: Apparatus for controlling various functions of a television receiver such as the picture and audio responses includes a keyboard with numbered keys which are normally used for selecting channels and a program key. When the program key is pressed, an on-screen character generator is caused to display a numbered list or menu of the various functions to be controlled. Thereafter, a particular function can be selected for control by pressing the correspondingly numbered key. This causes the numbered list or menu of the characteristics of the selected function, e.g., the brightness, contrast, sharpness, color level and color tint of the picture, to be displayed. Thereafter a particular characteristic can be selected for control by pressing the correspondingly numbered key.

Abstract: The present invention provides for the generation of digitally dithered digital signals which can have an apparent quantizing resolution unaffected by truncation of the least significant bit. The truncated digital signal is dithered in an ordered fashion by adding thereto a bit developed in response to one condition of the truncated bit and is not dithered in response to another condition thereof. The original digital signal can be reconstructed by combining successive samples of the truncated digital signals. One feature of the present invention provides a truncation of digital signals.

Abstract: The contrast of an image reproduced by a television receiver is manually adjustable by means of a picture control potentiometer, and automatically adjustable by means of an ambient light responsive circuit. Automatic picture control is accomplished selectively, independent of the manual control setting, in accordance with a predetermined combination of ambient light and image brightness levels such that the contrast of bright images, rather than the contrast of all images, is automatically reduced in low ambient light. In a preferred embodiment such automatic picture control is accomplished by using the light responsive circuit to control the threshold operating level of an automatic kinescope beam current limiter of the receiver.

Abstract: A defect compensation circuit of the type that substitutes a portion of delayed signal information for a real-time signal defect including circuitry for correcting chrominance phase reversal. The delayed signal is sampled at 1/2 the period of the chrominance before and after a 1H delay. The signal samples are summed and proportioned to provide a substitution signal having its chrominance signal in phase with the real time signal, and an average luminance signal exhibiting non-observable distortion.

Abstract: In a color television receiver including a comb filter for separating luminance and chrominance components of a color television signal, a network is included for selectively restoring, enhancing and paring vertical image detail to preserve and enhance vertical resolution in the luminance content of a displayed image. The comb filter provides a combed luminance signal output from which vertical detail signal information has been unavoidably deleted, and a combed chrominance signal output including signal frequency components representative of the deleted detail signal, which are selectively extracted from the combed chrominance signal. Low level detail signals are restored to the combed luminance signal via a first signal processing network which exhibits a prescribed signal restoration gain.

Abstract: A defect compensation circuit which substitutes a portion of delayed signal information for a real-time signal defect. A capacitor passes the a-c component of the delayed signal and stores the d-c component of the real-time signal to preclude the occurrence of d-c shifts upon effecting the substitution of signal.

Abstract: In a color television receiver including a comb filter for separating luminance and chrominance components of a color television signal, a network is included for selectively restoring and enhancing vertical image detail to preserve and enhance vertical resolution in the luminance content of a displayed image. The comb filter provides a combed luminance signal output from which vertical detail signal information has been unavoidably deleted, and a combed chrominance signal output including signal frequency components representative of the deleted signal, which are selectively extracted from the combed chrominance signal. Low level detail signals are restored to the combed luminance signal via a first signal processing network with a prescribed restoration gain.

Abstract: A novel pickup stylus adapted for playing back prerecorded signals from a video disc has an arrowhead-shape cross-section in the region of its tip. The pickup stylus includes a dielectric support element which has a prow defining the apex of the arrowhead-shape cross-section and a substantially flat rear surface remote from the prow defining the base of the arrowhead-shape cross-section. The entire rear surface is covered with conductive material to form a narrowed-electrode in the region of its tip.