JPS6451387U - - Google Patents

Description

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an adaptive luminance signal/color signal separation filter which is an embodiment of this invention, and FIG. 2 is a block diagram of a horizontal/vertical/time direction selective filter which is an embodiment of this invention. FIG. 3 is a block diagram showing an image correlation determination circuit that is an embodiment of this invention, and FIGS. 4, 5, 6, and 7 are time correlation detection circuits that are an embodiment of this invention. Circuit diagrams of the circuit, vertical correlation detection circuit, horizontal correlation detection circuit, and diagonal correlation detection circuit; FIG. 8 is a circuit diagram showing a determination circuit which is an embodiment of this invention; FIG. 9 is a circuit diagram showing another embodiment of this invention. A circuit diagram showing a determination circuit that is
Figures 10 and 11 are horizontal, vertical, horizontal-vertical,
An explanatory diagram showing the spatio-temporal arrangement of color signal phases and sample positions regarding the operating principle of a time direction selective filter. Fig. 12 is an explanatory diagram showing the arrangement of sample positions of an NTSC signal on a single field screen. Fig. 13 is horizontal
Regarding the operating principle of the vertical selection filter, FIG. 14 is an explanatory diagram showing the arrangement of color signal phases and sample positions on one field screen. 15
The figure is a block diagram of a horizontal/vertical direction selective filter in a conventional adaptive luminance/chrominance signal separation filter, and Figure 16 shows the passage of luminance signals and chrominance signals when using a conventional adaptive luminance/chrominance signal separation filter. It is an explanatory diagram showing a band. In the figure, 1 is an A/D converter, 2 is a horizontal/vertical/time direction selective filter, 3 is a delay element, and 4
is a subtracter, 5 is a horizontal/vertical direction selection filter,
6 is a delay element, 7 and 12 are 1F-1H delay devices, 8
, 11 is a 1H-2D delay device, 9 and 10 are 2D delay devices, 13 is a temporal color signal extraction filter, 14 is a vertical color signal extraction filter, 15 is a horizontal color signal extraction filter, and 16 is a horizontal/vertical color signal extraction filter. color signal extraction filter; 17; image correlation determination circuit; 18;
19, 20, and 21 are compensation delay circuits, 22 is a switch circuit, 23 is a temporal correlation detection circuit, 24 is a vertical correlation detection circuit, 25 is a horizontal correlation detection circuit, 26 is a diagonal correlation detection circuit, and 27 is a determination circuit. circuit, 28 is a subtraction circuit, 29 is an absolute value circuit, 30 is a constant generation circuit, 31 is a comparison circuit, 32 is a vertical direction LPF, 33 is a vertical direction BPF, 34 is a horizontal direction BPF, 35 is a compensation delay circuit, 36, 37 is an absolute value circuit, 38 and 40 are constant generation circuits, 39 and 41
42 is a comparison circuit, 42 is a vertical correlation determination circuit, 43 is a vertical BPF, 44 is a horizontal BPF, 45 is a horizontal LPF, 46 is a compensation delay circuit, 47, 48
is an absolute value circuit, 49 and 51 are constant generation circuits, and 50
, 52 is a comparison circuit, 53 is a horizontal correlation determination circuit, 5
4 and 55 are diagonal BPFs, 56 and 57 are absolute value circuits, 58 is a subtracter, 59 is an absolute value circuit, 60 is a constant generation circuit, 61 is a comparison circuit, 62a, 62b
, 62c, 62d are NOT circuits, 63a, 63b
, 63c, 63d, 63e, 63f, 63g are A
ND circuit, 64 is OR circuit, 65a, 65b, 6
5c, 65d, 65e are NOT circuits, 66a, 6
6b, 66c, 66d, 66e, 66f, 66g
, 66h is an AND circuit, 67 is an OR circuit, 68 is an EXOR circuit, 69 and 72 are 1H delay devices, 70,
71 and 73 are 2D delay devices, 74 and 77 are adders,
75, 76, 83, 84 are subtracters, 78, 80,
82 is a multiplier, 79 and 81 are absolute value circuits, 85 is a comparator, and 86 is a switch circuit. In addition, in the figures, the same reference numerals indicate the same or equivalent parts.

Claims (1)

[Claims for Utility Model Registration] (1) A composite video signal sampled at a predetermined frequency synchronized with the horizontal scanning frequency so that each sample point is arranged in a grid on the screen is input, and In a luminance signal/chrominance signal separation filter that digitally separates luminance signal components and chrominance signal components, the composite video signal is delayed to separate the luminance signal and chrominance signal at a sample point of interest and on the screen. a delay means for simultaneously obtaining a plurality of reference sample points that are aligned in a straight line in the time direction with the sample point of interest, and a delay means and an addition means for inputting the sample values of the sample point of interest and a predetermined reference sample point. , subtracting means, and multiplication means to perform calculations and pass either the high-frequency component or the low-frequency component of the video signal,
Using a horizontal color signal extraction filter, a vertical color signal extraction filter, a horizontal/vertical color signal extraction filter, and a temporal color signal extraction filter, and sample points adjacent in the time direction whose color subcarrier phase is inverted with respect to the sample point of interest. A time direction difference absolute value detection means for calculating the time direction difference absolute value from the neighboring sampling points for the input image, and excluding a vertical direction DC component and color subcarrier frequency component from the sample point of interest and its neighboring sample points. and vertical uncorrelated energy detection means for detecting vertical uncorrelated energy by excluding the horizontal color subcarrier frequency component and finding its absolute value; A vertical high-frequency luminance signal in which a frequency component that is a low-frequency component in the horizontal direction and corresponds to one-half of the color subcarrier frequency in the vertical direction is extracted from the frequency component, and its absolute value is determined. energy detecting means, excluding a DC component in a horizontal direction and a color subcarrier frequency component, excluding a color subcarrier frequency component in a vertical direction, and excluding a color subcarrier frequency component in a vertical direction from a sample point of interest and its neighboring sample points; horizontally uncorrelated energy detecting means for detecting the horizontally uncorrelated energy by determining its absolute value; 2 of the color subcarriers in the horizontal direction.
A horizontal high-frequency luminance signal energy detection means for extracting a frequency component corresponding to 1/200% and calculating its absolute value, and a DC component and a color subcarrier frequency component in the diagonally upward direction to the right from the sample point of interest and its neighboring sample points. diagonal upward-rightward uncorrelated energy detection means for detecting obliquely upward-rightward uncorrelated energy by excluding and finding its absolute value; a diagonal right-down direction uncorrelated energy detection means for detecting diagonally right-down direction uncorrelated energy by excluding a frequency component and finding its absolute value; and the time direction difference absolute value and a first setting value given from the outside. time correlation detection means that compares the magnitude of the difference in the time direction and determines that there is a correlation in the time direction when the absolute value of the difference in the time direction is less than or equal to the first set value; The vertical direction uncorrelated energy is smaller than the second setting value, and the horizontal direction high-frequency luminance signal energy is compared with the third setting value given from the outside. Compare the
vertical correlation detection means for determining that there is a correlation in the vertical direction when the horizontal high-frequency luminance signal energy is larger than a third set value; and the horizontal uncorrelation energy and a fourth set value given from the outside. , and the horizontal direction uncorrelated energy is smaller than the fourth set value, and the vertical direction high-frequency luminance signal energy is compared with a fifth set value given from the outside,
horizontal correlation detection means for determining that there is a correlation in the horizontal direction when the vertical high-frequency luminance signal energy is greater than the fifth set value; a determination result of the temporal correlation detection means; a determination result of the vertical correlation detection means; The judgment result of the horizontal correlation detection means, the detection result of diagonally upward-right direction uncorrelated energy, and the diagonally downward-rightward direction uncorrelated energy detection result are input, and if there is a temporal correlation, the output of the temporal direction color signal extraction filter is selected. When a signal is sent, and there is no time correlation, the absolute value of the difference between the diagonally upward-right direction uncorrelated energy detection result and the diagonally right-downward direction uncorrelated energy detection result is determined from the sixth setting value given externally. If the correlation is small and there is a correlation in the horizontal direction, a control signal is sent to select the output of the horizontal color signal extraction filter, and a control signal is sent to select the output of the horizontal color signal extraction filter, and the result of detecting the uncorrelated energy in the diagonally upward right direction and the uncorrelated energy detection result in the diagonally downward right direction is detected. If the absolute value of the difference is smaller than the sixth set value, and there is no correlation in the horizontal direction but correlation in the vertical direction, a control signal for selecting the vertical color signal extraction filter is sent, and the filter is moved diagonally upward to the right. The absolute value of the difference between the non-correlated energy detection result and the diagonally downward-sloping non-correlated energy detection result is smaller than the sixth set value, and there is no correlation in both the horizontal and vertical directions, or the absolute value of the difference is a determining means for transmitting a control signal for selecting a horizontal/vertical color signal extraction filter output when the value is larger than the sixth set value; and a switch for outputting a color signal component in accordance with the control signal transmitted by the determining means. 1. A luminance signal/chrominance signal separation filter for image correlation, comprising: a subtraction circuit that subtracts the output of the switch circuit from the composite video signal to output a luminance signal component. (2) The determination means includes the determination result of the time correlation detection means, the determination result of the vertical correlation detection means, the determination result of the horizontal correlation detection means, the detection result of diagonally upward-to-the-right direction non-correlation energy, and the result of diagonally-down-to-the-right direction non-correlation energy detection. When there is a time correlation, a control signal is sent to select the output of the time direction color signal extraction filter, and when there is no time correlation, the detection results of diagonally upward-sloping uncorrelated energy and diagonally downwards-sloping direction non-correlated energy are input. If the absolute value of the difference with the correlation energy detection result is smaller than the sixth setting value given from the outside, and there is correlation in the horizontal direction but no correlation in the vertical direction, select the output of the horizontal color signal extraction filter. The absolute value of the difference between the diagonally upward-right direction uncorrelated energy detection result and the diagonally right-downward direction uncorrelated energy detection result is determined by
is smaller than the set value, and there is no correlation in the horizontal direction, but there is correlation in the vertical direction, a control signal is sent to select the vertical color signal extraction filter output, and the diagonal upward-to-right direction uncorrelated energy detection result and diagonal The absolute value of the difference from the downward-sloping uncorrelated energy detection result is smaller than the sixth setting value, and there is or is no correlation in both the horizontal and vertical directions, or the absolute value of the difference is the sixth setting value. Image correlation compatible luminance signal color according to claim 1 of the utility model registration claim, characterized in that when the value is larger than the value, a control signal for selecting the output of the horizontal/vertical color signal extraction filter is sent out. Signal separation filter.