Motion detection circuit for high definition television based on muse

A motion detection circuit in a MUSE decoder for reproducing a high definition television picture signal from a MUSE signal, comprising:

• a two-dimensional filter including a vertical filter means for obtaining one-interframe differential signal from an interframe interpolation signal, the interframe interpolation signal being determined solely from present field transmitted data and data transmitted one frame earlier interpolated therein, said vertical filter means attenuating frequency components in a neighborhood of a predetermined vertical frequency in a slantwise direction, and a horizontal filter means for separating an output signal of said vertical filter means into a high frequency component signal above a predetermined horizontal frequency and a low frequency component signal below said predetermined horizontal frequency;
• first peak detector means coupled to said horizontal filter means for obtaining and outputting a peak value of said low frequency component signal below said predetermined horizontal frequency;
• horizontal width extender means, coupled to said first peak detector means and said horizontal filter means, for holding said peak value output from said first peak detector means for a tap length of said horizontal filter means, said horizontal width extender means outputting a peak value nearest to a current level of said low frequency component signal below said predetermined horizontal frequency;
• and
• non-linear circuit means coupled to said horizontal filter means, for effecting a non-linear conversion to said low frequency component signal below said predetermined horizontal frequency, thereby effecting an adjustment for an attenuation of high frequency components in said low frequency component signal.

A motion detection circuit in MUSE decoder for reproducing a high definition television picture signal from a MUSE signal comprising:

• interpolator means, receiving current field transmission data for interpolating data transmitted one frame earlier into said current field transmission data;
• first field memory means, operatively connected to said interpolator means, for delaying an output signal of said interpolator means by 560 horizontal scanning periods;
• second field memory means, operatively connected to said first field memory means, for delaying an output signal of said first field memory by 565 horizontal scanning periods, said second field memory means effecting vertical motion correction to the output signal of said first field memory in response to a vertical motion vector;
• first horizontal motion corrector means operatively connected to said second field memory means, for effecting first horizontal motion correction to an output signal of said second field memory in response to horizontal motion vector;
• and
• second horizontal motion corrector means, operatively connected to said first field memory means, for effecting second horizontal motion correction to the output signal of said first field memory in response to a horizontal motion vector.

A motion detection circuit in MUSE decoder for reproducing a high definition television picture signal from a MUSE signal, comprising:

• one-interframe differential calculator means coupled to an input terminal receiving an interframe interpolation signal consisting of present transmitted data and data transmitted one frame earlier interpolated therein, said one-interframe differential calculator means calculating one-interframe differential signal from said interframe interpolation signal;
• horizontal filter means coupled to said one-interframe differential calculator means, for extracting a low frequency component signal of said one-interframe differential signal output from said one-interframe differential calculator means;
• two-value signal generator means coupled to said one-interframe differential calculator means, for converting said one-interframe differential signal into a two-value signal on the basis of a predetermined threshold level;
• frame memory means coupled to said two-value signal generator means, for delaying said two-value signal by one frame;
• switcher circuit means having an input receiving two-interframe differential signal obtained by subtracting a signal transmitted two frames earlier from the present transmitted signal, said switcher circuit means having another input terminal coupled to an output of said frame memory means, said switcher circuit means limiting two-dimensional picture region of said two-interframe differential signal by means of the output signal of said frame memory means;
• wherein said motion detection circuit provides motion detection information contained in said low frequency component signal output from said horizontal filter means and the two-interframe differential signal output from said switcher circuit means.

A motion detection circuit in MUSE decoder for reproducing a high definition television picture comprising:

• interpolator means having an input terminal receiving current field transmission data, for interpolating data transmitted one frame earlier into a current field transmission;
• interframe differential signal extractor means coupled to said interpolator means, for extracting one-interframe differential signal from an output signal of said interpolator means;
• interfield differential signal extractor means coupled to said interpolator means, for extracting one-interfield differential signal from an output signal of said interpolator means;
• first two-dimensional filter means coupled to said interframe differential signal extractor means, for attenuating frequency components of said one-interframe differential signal near vertical frequency 1125/4 cycles/height (c/h) in a slantwise direction;
• second two-dimensional filter means coupled to said interfield differential signal extractor means, for attenuating frequency components of said one-interfield differential signal near the vertical frequency 1125/4 (c/h) in the slantwise direction;
• first horizontal filter means coupled to said first two-dimensional filter means, for separating an output signal of said first two-dimensional filter means into a high frequency component signal and a low frequency component signal;
• second horizontal filter means coupled to said second two-dimensional filter means, for separating an output signal of said second two-dimensional filter means into a high frequency component signal and a low frequency component signal;
• first edge improver means coupled to said first horizontal filter means, for improving edge portions of said low frequency component signal output from said first horizontal filter means;
• second edge improver means coupled to said second horizontal filter means, for improving edge portions of said low frequency component signal output from said second horizontal filter means;
• first folding disturbance component remover means coupled to said first horizontal filter means, for removing folding disturbance components for still picture processing from said high frequency component signal output from said first filter means;
• second folding disturbance component remover means coupled to said second horizontal filter means, for removing folding disturbance components for still picture processing from said high frequency component signal output from said second filter means;
• first selector means coupled to said first edge improver means and said first folding disturbance component remover means, for selecting and reproducing one-interframe differential signal;
• second selector means coupled to said second edge improver means and said first folding disturbance component remover means, for selecting and reproducing one-interfield differential signal;
• horizontal extender means coupled to said second selector means, for obtaining a peak value among adjacent data in horizontal direction, thereby compensating for motion information drop caused by subsampling in accordance with MUSE system;
• vertical extender means coupled to said horizontal extender means, for obtaining a peak value among adjacent data in vertical direction, thereby compensating for motion information drop caused by subsampling in accordance with MUSE system;
• and
• third selector means coupled to said first selector means and said vertical extender means, for obtaining motion information in accordance with output signals of said first selector means and said vertical extender means.

A method of motion detection in a MUSE (multiple sub-Nyquist encodation) decoder comprising:

• a) detecting edges in present video signal frame information and producing an edge information signal;
• b) receiving interleaved present and previous video signal frame information as an interfield signal;
• c) obtaining a differential motion signal from the interfield signal;
• d) filtering the differential motion signal to remove high frequencies in a frequency range where folding disturbance signals may exist to produce a filtered differential motion signal;
• e) selectively adding high frequency information in the frequency range where folding disturbance components exist to the filtered differential motion signal only when the high frequency information is not due to folding disturbances in the video signal to produce a high frequency enhanced motion signal to enhance the reproduction of moving images;
• and
• f) adjusting sensitivity of said high frequency enhanced motion signal in the area of image edges in response to said edge information signal to produce motion detection data.