摘要:
An HDTV system wherein the HDTV signals may have the same frequency band as that of the conventional color television signals and be transmitted through a unoccupied channel of the conventional color television system, is disclosed. The HDTV system includes a ITLC circuit for compressing on time-base the digital signals; a band separation circuit for separating the output signal of the ITLC circuit into low and high frequency band signal; a motion vector detector for detecting motion vector from the low frequency band signals; a high frequency band signal processor for processing the high frequency band signals according to the output of motion vector detector; a first LPF for filtering the high frequency analog signal; a second LPF for filtering the low frequency analog signal; and a quadrature modulator for multiplying the output of the first and second LPF, respectively, by Cos .omega.t signal and Sin .omega.t signal, and thereafter adding the multiplied signals to each other to produce therefrom a transmission signal.
摘要:
A method which can be used to enhance an outline of an image displayed in an image display apparatus such as a television receiver, and a circuit performing the method. The circuit includes a peaking signal generation circuit which generates a first peaking signal and a second peaking signal corresponding to an amplitude transition of a video signal. A first peaked video signal generation circuit generates a first peaked video signal by adding the first peaking signal to the video signal. A control signal generation circuit generates a first control signal based on a result of comparing a first-order differential signal developed by differentiating the video signal with a reference signal, and a second control signal by delaying the first control signal for the predetermined period. A first selection circuit selects either the video signal or the first peaked videos signal according to the first control signal. A second peaked video signal generation circuit generates a second peaked video signal by adding the second peaking signal to the first selected signal. And, a second selection circuit selects either the first selected signal or the second peaked signal to develop a second selected signal, and outputs the second selected signal as an enhanced video signal. Therefore, the circuit can enhance an outline of an image formed by a video signal without modifying an amplitude transition time of the video signal and introducing the preshoot and overshoot into the video signal.
摘要:
A method for receiving a high definition television signal has been used by the band-splitting and sub-sampling method. The concrete embodiment for the method can be accomplished by converting the received radio frequency signal into a first intermediate frequency signal, and by splitting a second intermediate frequency signal and a narrow band intermediate frequency signal therefrom. The narrow band intermediate frequency signal is lacked a given fixed frequency to demodulate the second intermediate frequency signal in a quadrature phase-shift technique. The demodulated signal is low-pass filtered and converted into a digital signal to separate into a synchronizing, an audio signal, a control signal therefrom. The digital signal is processed at high frequency band according to the control signal, and delayed a given time. The delayed signal is added to the signal processed at high frequency band. The added signal is separated into a luminance and chrominance signals to convert into an analog signals.