A still/slow circuit for use in a two-head type VCR includes a digital counter for counting slow indication signals, a pulse oscillator for outputting slow drive control signals in response to outputs of the digital counter, an envelope detector for integrating playback video signals to detect envelopes therefrom, a differentiator for differentiating head-switching signals to output only positive pulse signals, a sample/hold unit for sampling and holding the output signals of the envelope detector by being triggered with the positive pulse signals of the differentiator, an OR-gate unit which allows still indication signal and slow indicating signal to pass therethrough, a comparing unit for comparing as to whether or not the output signal level of the envelope detector is same as the output signal level of the sample/hold unit and outputting an oscillation drive voltage when they do not coincide with each other, a pulse oscillator for outputting still drive control signals, and a differentiator for differentiating the frame advance indication signals to apply those signals together with the output signals of the sample/hold unit to the comparing unit, whereby the still/slow circuit carries out the still playback, slow playback, and frame advance operations.
Apparatus and methods for an electronic guide with video clips are provided. The method includes the step of providing a video cassette tape having a first length of video cassette tape having a first index mark written in the control track near the beginning of the first length and a second index mark written in the control track near the end of the first length, a guide grid to video clips on the video cassette tape written in the video track between the first and second index mark, and guide data written as tones in the audio track between the first and second index mark, the guide data associated with the guide grid including for each video clip contained on the video cassette tape a number of index marks either forward or backward on the tape from the guide data to the video clip. A plurality of video clips are provided on the video cassette tape, each video clip having a third and fourth index marks written in the control track near the beginning and end, respectively, of the video clip, video for the video clip written in the video track between the third and fourth index mark, and audio to accompany the video written in the audio track between the third and fourth index mark. In another method the electronic guide with video clips is broadcast with an initialization message and broadcast indication near the start of the broadcast.
Charges are read out from a CCD n (where n is an integer or greater) times within 1 field period, under the control of a controller. Under the control of a memory controller, a VTR records the n images as a video signal for 1 field, based on the readout charges. When playing back, under control of the memory controller, the video signal for 1 field, which is read out from the VTR and which includes n images, is temporarily stored in a memory. The memory controller reads out the n images from the memory in time sequence, and displays each image on a display m (where m is an integer 1 or greater) times during period of m fields, thereby performing slow playback at a playback speed of 1/(n.times.m). Along with a video signal for each field, the VTR records information with regard to the number n of the images and the display positions thereof.
An apparatus and a method for controlling automatically a fine-slow in a VCR comprises a servo control device for controlling an operation of a capstan motor, a control head for detecting a control pulse from a video tape and applying the detected control pulse to the servo control device, a Schmidt trigger circuit for Schmidt-wave shaping the detected control pulse from the control head, an envelope detector for receiving a playback radio frequency signal and detecting an envelope signal of DC component from the received signal, and a microcomputer for sampling the detected envelope signal from the envelope detector in intervals of a head switching signal of the front and rear of the control pulse in a slow playback interval, A/D-converting the sampled values, comparing the digital sampled values with each other and applying slow control data based on the comparison of the digital sampled values to the servo control device to control shift of the control pulse, the slow control data being data for controlling the capstan motor in a slow mode. The microcomputer compares the sampled values with each other and control shift of the control pulse in a positive (+) or negative (-) direction in accordance with the compared result until the sampled values are the same.
An apparatus and a method of controlling tracking in slow mode playback. The tracking control apparatus comprises a video head for detecting a video signal recorded on a magnetic tape, a video signal processing circuit for detecting envelopes of the detected video signal from the video head, a microcomputer for outputting servo data and a slow tracking signal in response to the detected envelopes from the video signal processing circuit, a servo device for outputting a capstan phase control signal in response to the servo data from the microcomputer, and a capstan motor for driving a capstan in response to a signal into which the capstan phase control signal from the servo device and the slow tracking signal from the microcomputer are combined.
A variable-speed regeneration compensating apparatus for a double azimuth 4-head type video tape recorder comprises first and second standard speed regenerating heads, first and second low speed regenerating heads, a standard speed regeneration head switching part, a standard speed regeneration envelope detecting part, a low speed regeneration envelope detecting part, an envelope comparing part, a standard speed recorded medium regeneration signal switching part, first and second time constant circuits, a time constant circuit switching part, and a low speed recorded medium variable speed regeneration compensating circuit. Compensation is provided not only to the case where the picture data having undergone a standard speed recording which is subjected to variable speed reproduction, but also to the medium having undergone a low speed recording, and therefore the stripe shaped optical noise is eliminated making the low speed recording/regenerating of video tapes easier.
