Back to results
US 5,206,715 AGranted
Circuit for separating luminance and chrominance signals
AssigneeSamsung Electronics Co., Ltd.
InventorsJun-mo Jung, Jeong-sang Lee
Life of this patent
Estimating the term…
Abstract
A circuit for separating the luminance signal and chrominance signal from a composite video signal in a digital signal processing system using adaptive 2H comb filters. The circuit according to the present invention generates luminance difference signals, and chrominance difference signals from the horizontal scanning lines of a composite video signal for the purpose of detecting the correlation of the chrominance difference signals as well as the correlation of the luminance difference signals to generate a correlation coefficient. The chrominance signal is accurately separated from a composite video signal in response to the generated correlation coefficient.
Claims15
A circuit for separating the luminance and chrominance signals from a composite video signal in a color video signal processing system, comprising:
- first delay means for delaying a composite video signal over a predetermined time interval to provide a first delayed signal;
- second delay means for delaying said first delayed signal at said predetermined time interval to provide a second delayed signal;
- first subtractor means for subtracting said composite video signal from said first delayed signal to provide a first subtracted signal;
- first adder means for adding said first delayed signal to said composite video signal to provide a first added signal;
- second adder means for adding said first delayed signal to said second delayed signal to provide a second added signal;
- second subtractor means for subtracting said second delayed signal from said first delayed signal to provide a second subtracted signal;
- first filter means for filtering said first and second subtracted signals respectively over a first predetermined bandwidth to provide first and second luminance difference signals;
- second filter means for filtering said first and second added signals respectively over a second predetermined bandwidth to provide first and second chrominance difference signals;
- correlation detector means for detecting correlation of said first and second luminance difference signals and said first and second chrominance difference signals to generate a plurality of correlation control signals;
- coefficient generator means for logically combining said plurality of correlation control signals to generate a correlation coefficient;
- third filter means for filtering said first delay signal over a third predetermined bandwidth to provide an intermediate signal;
- and
- multiplexer means for receiving and for selectively transmitting one of said intermediate signal, and said first and second subtracted signals in accordance with said correlation coefficient.
10 more elements
A circuit for separating the luminance and chrominance signals from a composite video signal in a color video signal processing system, comprising:
- first delay means for providing a first delayed signal by delaying an input composite video signal by a predetermined time interval;
- second delay means for providing a second delayed signal by delaying said first delayed signal by said predetermined time interval;
- subtractor means for providing differences of said input composite video signal after each delay by subtracting each input composite video signal from a subsequent output composite video signal;
- adder means for providing summations of said input composite video signal after each delay by adding said input composite video signal and said subsequent output composite video signal;
- low-pass filter means for providing a plurality of luminance difference signals from said input composite video signal by low-pass filtering the differences of said input composite video signal after each delay;
- band-pass filter means for providing a plurality of chrominance difference signals from said input composite video signal by band-pass filtering the summations of said input composite video signal after each delay;
- means for detecting correlations of said plurality of luminance difference signals and said plurality of chrominance difference signals, and for generating a correlation coefficient;
- filter means for providing a filtered signal by filtering the output of said first delay means;
- and
- multiplexer means for receiving the filtered signal and the differences of said input composite video signal after each delay, and selectively transmitting one of said filtered signal and the differences of said input composite video signal in accordance with said correlation coefficient.
7 more elements
A method for separating the luminance and chrominance signals from a composite video signal in a color video signal processing system, comprising the steps of:
- delaying an input composite video signal by one horizontal line to provide a first delayed signal;
- delaying said first delayed signal by one horizontal line to provide a second delayed signal;
- subtracting said first delayed signal from said input composite video signal and subtracting said second delayed signal from said first delayed signal to respectively provide first and second line difference signals;
- adding said first delayed signal to said input composite video signal and adding said second delayed signal to said first delayed signal to respectively provide first and second line summation signals;
- low-pass filtering said first and second line difference signals to provide first and second luminance difference signals;
- band-pass filtering said first and second line summation signals to provide first and second chrominance difference signals;
- detecting correlations of said first and second luminance difference signals, and said first and second chrominance difference signals, to provide a plurality of correlation control signals;
- generating a correlation coefficient in response to said plurality of correlation control signals;
- band-pass filtering said first delayed signal to provide a chrominance signal;
- and
- selecting one of said chrominance signal and said first and second line difference signals in response to said correlation coefficient.
8 more elements
A method for separating the luminance and chrominance signals from a composite video signal in a color video signal processing system, comprising the steps of:
- delaying an input composite video signal by one period to provide a first delayed signal;
- delaying said first delayed signal by one period to provide a second delayed signal;
- subtracting said first delayed signal from said input composite video signal and subtracting said second delayed signal from said first delayed signal to respectively provide first and second line difference signals;
- adding said first delayed signal to said input composite video signal and adding said second delayed signal to said first delayed signal to provide first and second line summation signals;
- filtering said first and second line difference signals to provide first and second luminance difference signals;
- filtering said first and second line summation signals to provide first and second chrominance difference signals;
- detecting correlations of said first and second luminance difference signals, and said first and second chrominance difference signals, to provide a plurality of correlation control signals;
- generating a correlation coefficient in response to said plurality of correlation control signals;
- filtering said first delayed signal to provide a chrominance signal;
- and
- selecting one of said chrominance signal and said first and second line difference signals in response to said correlation coefficient.
8 more elements
Dependencies are inferred from the claim text.