Spectrum distribution luminance/color signal separating device

A luminance/color signal separating device comprising:

• a means for receiving a composite video signal;
• a band-pass filter means for detecting a composite video signal existing in a predetermined frequency band having a centered chrominance subcarrier frequency from said composite video signal;
• a band-rejection filter means for removing a composite video signal existing in a predetermined frequency band having a centered chrominance subcarrier frequency from said composite video signal;
• a first line comb filter means for separating a luminance signal and a color signal from an output signal of said band-pass filter means by a correlation between three lines;
• a second line comb filter means for separating a luminance signal and a color signal from an output signal of said band-pass filter means by a correlation between five lines;
• a frame comb filter means for separating a luminance signal and a color signal from an output signal of said band-pass filter means by a correlation between frames;
• a vertical variation detecting means for detecting a variation component of picture in a vertical axis from an output signal of said band-pass filter means;
• a temporal variation detecting means for detecting a variation component of picture in a temporal axis from an output signal of said band-pass filter means;
• a horizontal variation detecting means for detecting a variation of picture in a horizontal axis from said composite video signal;
• a first mixing means for mixing color signals separated by said first and second line comb filter means, and said frame comb filter means, and an output signal of said band-pass filter means, according to detected results of said horizontal, vertical and temporal variation detecting means;
• a second mixing means for mixing luminance signals separated by said first and second line comb filter means and said frame comb filter means, and an output signal of said band-rejection filter means, according to detected results of said vertical, temporal variation detecting means;
• wherein said vertical variation detecting means further comprises;
• a second band-pass filter means for extracting a composite video signal distributed in a band having principal frequencies of 1/4(n+1) Fn and 3/4(n+1)Fn from an output signal of said band-pass filter means;
• a first demultiplying means for dividing an output signal of said band-pass filter means by an output signal of said second band-pass filter means;
• and
• a first threshold comparator for comparing an output signal of said first demultiplying means with a threshold of predetermined level to generate a control signal of logic signal type and supplying a generated control signal to said first mixing means.

A luminance/color signal separating device comprising:

• a means for receiving a composite video signal;
• a band-pass filter means for detecting a composite video signal existing in a predetermined frequency band having a centered chrominance subcarrier frequency from said composite video signal;
• a band-rejection filter means for removing a composite video signal existing in a predetermined frequency band having a centered chrominance subcarrier frequency from said composite video signal;
• a first line comb filter means for separating a luminance signal and a color signal from an output signal of said band-pass filter means by a correlation between three lines;
• a second line comb filter means for separating a luminance signal and a color signal from an output signal of said band-pass filter means by a correlation between five lines;
• a frame comb filter means for separating a luminance signal and a color signal from an output signal of said band-pass filter means by a correlation between frames;
• a vertical variation detecting means for detecting a variation component of picture in a vertical axis from an output signal of said band-pass filter means;
• a temporal variation detecting means for detecting a variation component of picture in a temporal axis from an output signal of said band-pass filter means;
• a horizontal variation detecting means for detecting a variation of picture in a horizontal axis from said composite video signal;
• a first mixing means for mixing color signals separated by said first and second line comb filter means, and said frame comb filter means, and an output signal of said band-pass filter means, according to detected results of said horizontal, vertical and temporal variation detecting means;
• a second mixing means for mixing luminance signals separated by said first and second line comb filter means and said frame comb filter means, and an output signal of said band-rejection filter means, according to detected results of said vertical, temporal variation detecting means;
• wherein said horizontal variation detecting means further comprises;
• a third band-pass filter means for extracting a composite video signal existing in a predetermined frequency band having a centered chrominance subcarrier frequency from said composite video signal supplied from said input means;
• a fourth band-pass filter means for extracting a composite video signal existing in a predetermined frequency band having a centered 1/2-chrominance subcarrier frequency from said composite video signal supplied from said input means;
• a second demultiplying means for dividing an output signal of said third band-pass filter means by an output signal of said fourth band-pass filter means;
• and
• a second threshold comparing means for comparing an output signal of said second demultiplying means with a threshold of predetermined level to generate a control signal of logic signal type, and supplying a generated control signal to said first and second mixing means.