JP2001086525A - Image signal processor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To further improve image quality by providing a first selection means and a second selection means for alternately selecting a second luminance signal outputted from a matrix circuit and a synthetic signal from a fourth synthesis means for each field, etc. SOLUTION: This processor is provided with a changeover switch 31 for alternately selecting a first luminance signal outputted from the matrix circuit 51 and a synthetic signal from a third synthesis means for each field and the changeover switch 33 for alternately selecting the second luminance signal outputted from the matrix circuit 51 and the synthetic signal from the fourth synthesis means for each field. By this constitution, even when the characteristic difference of third and fourth solid-state image pickup elements and the difference of gain and linearity in an analog signal processing part are present, the image quality is further improved since the DC difference of the high-vision type image signals of every other line due to the differences is averaged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image signal processing apparatus, and more particularly to a high definition image signal such as a high vision system using a solid-state image pickup device for a standard television system image signal such as an NTSC system or a PAL system. The present invention relates to an image signal processing device for obtaining

[0002]

2. Description of the Related Art As an imaging device for obtaining a high-definition Hi-Vision image signal compared to a standard television image signal such as the NTSC system or the PAL system, a dedicated imaging device requires a high signal processing speed. Also, peripheral devices to be used have high power consumption, require high precision, and are extremely expensive. For this reason, the present applicant has previously proposed an image signal processing apparatus for obtaining a high-definition image signal of a high-vision system or the like using a solid-state imaging device for a standard television image signal (for example, see Japanese Patent Application Laid-Open No. -327233, JP-A-9-74571, etc.).

For example, an image signal processing apparatus proposed by the present applicant described in Japanese Patent Application Laid-Open No. 9-74571 has a color separation optical system as shown in FIG. 4 as an example, and a solid-state image sensor as shown in FIG. And a signal processing circuit as shown in FIG.

As shown in FIG. 4, the color separation optical system of this image pickup apparatus includes a B prism 10 for extracting a blue (B) light component from incident light, and a light transmitted from the B prism 10 through a dichroic film 10a. An R prism 12 for extracting a red (R) light component, and a G prism 14 for extracting a green (G) light component from light transmitted through the R prism 12.
And a half mirror 16 provided on the G prism, and blue solid light reflected and extracted from the B prism 10 by the dichroic film 10a and the incident surface of the B prism 10, respectively, through the B trimming filter 13. The red light reflected and extracted from the element 19B and the dichroic film 12a of the R prism 12 and the incident surface of the R prism 12, respectively,
The first solid-state image sensor 1R for green which is reflected by the half mirror 16 and which receives the green light through the G trimming filter 17
9G1 and a second green solid-state imaging device 19G2 to which green light transmitted through the half mirror 16 and the G trimming filter 18 is incident.

The solid-state imaging devices 19B, 19R, 19G1 and 19G2 are each constituted by a charge-coupled device (CCD), and have an aspect ratio of 1 in a high-vision system.
For example, each pixel is composed of 804 × 516 pixels corresponding to 6: 9 and included in the area of the PAL image sensor.

The solid-state image sensors 19G1 and 19G2 for green color
Are arranged so as to be shifted by one pixel pitch in the vertical direction and by 画素 pixel pitch in the horizontal direction, and to be shifted by ピ ッ チ pitch in the vertical direction with respect to one of the green solid-state image sensors. 19B and 19R are arranged respectively. As a result, a pixel position on the high-definition screen as shown in FIG. 5 is obtained. In the figure, capital letters G, B,
R is an odd field, small letters g, b, and r are pixels read out in even fields, respectively, and "G" and "g" are green signals (hereinafter also referred to as G signals), "R" and "r". Indicates a pixel of a red signal (hereinafter also referred to as an R signal), and "B" and "b" indicate pixels of a blue signal (hereinafter also referred to as a B signal), respectively. Further, "rb" and "R
“B” is a pixel from which the R signal and the B signal are simultaneously and separately read from the respective solid-state imaging devices 19R and 19B.

[0007] These four solid-state imaging devices 19B, 19B
Since R, 19G1, and 19G2 are driven simultaneously, the same pixels in the horizontal direction, m pixels, and the vertical direction, n lines, are read out simultaneously. For example, G1m, n, G2m, n, RB
Four of m, n (= Rm, n, Bm, n) are read simultaneously in odd-numbered fields. Focusing on the positions of R, r, B, and b pixels, pairs of these pixels are arranged in both odd and even fields. This is because the R solid-state image sensor 19R and the B solid-state image sensor 19B
Are arranged at the same pitch without shifting in the vertical direction.

Next, these four solid-state imaging devices 19B,
A processing device for the imaging signals output from 19R, 19G1, and 19G2 will be described with reference to the block diagram of FIG.
In the figure, B pixel data DB and R pixel data DR taken out from B and R solid-state imaging devices and obtained through an A / D converter (not shown) are stored in field memories 21 and 22 and a frame synthesis circuit 23. , 24 and are input to the corresponding vertical high-pass filters 25 and 26. The vertical high-pass components extracted from the vertical high-pass filters 25 and 26 are supplied to adders 27 and 28, respectively, and are subjected to an addition operation by the following equation to generate vertical high-pass frequency signals VH1 and VH2.

[0009]

(Equation 1) On the other hand, input digital signals (pixel data) DB, DR, DG1 and DG2 of 10 bits each are
The luminance signal Y1, Y2, y1, and y2 of 8 bits are generated by the matrix operation of the following equations (3) to (6).

Y1m, n = 0.701G1m, n + {0.212 (Rm, n + Rm + 1, n) / 2} +0.087 (Bm, n + Bm + 1, n) / 2 (3) Y2m, n = 0.701 G2m, n + 0.212Rm, n + 0.087Bm, n (4) y1m, n = 0.701g1m, n + {0.212 (rm, n + rm + 1, n) / 2} +0.087 (bm, n + bm + 1 , n) / 2 (5) y2m, n = 0.701g2m, n + 0.212rm, n + 0.087bm, n (6) Further, the matrix circuit 29 uses the following equations (7) to (10) to calculate the color difference signal ( (RY), (BY), (ry) and (by) are generated and output.

(RY) m + 1, n = Rm + 1, n−Ym + 1, n (7) (BY) m, n = Bm, n−Ym, n (8) (r− y) m + 1, n = rm + 1, n-ym + 1, n (9) (by) m, n = bm, n-ym, n (10) Luminance signal output from matrix circuit 29 Y1 and y
1 is supplied to the adder 30 and added to the vertical high-frequency signal VH1 from the adder 27, thereby obtaining a wideband high-frequency additional signal Y1 ^* represented by the following equation.

Y1 ^* m, n = Y1m, n + VH1m, n (11) The luminance signal Y2 output from the matrix circuit 29
, And y2 are supplied to the adder 31 and added to the vertical high frequency signal VH2 from the adder 28, thereby obtaining a wideband high-frequency additional signal Y2 ^* represented by the following equation.

Y2 ^* m, n = Y2m, n + VH2m, n (12) The change-over switch 32 selects the high-frequency additional signal Y1 ^* for the odd field based on the field pulse, and the 8-bit of the matrix circuit 29 for the even field. The output signal y1 is selected as it is. Similarly, the changeover switch 33 selects the high-frequency additional signal Y2 ^* for odd fields and the matrix circuit 29 for even fields based on the field pulse.
Is selected as it is.

The double speed conversion circuit 34 is provided with these changeover switches 3
Based on the output signals 2 and 3 and the color difference signal output from the matrix circuit 29, a luminance signal Y and color difference signals RY and BY of the Hi-Vision system are generated and output, respectively. The double speed conversion circuit 34 is configured by a line memory and a switch circuit.

According to the imaging apparatus proposed by the present applicant, the 8-bit luminance signal Y 1 (y 1) extracted from the matrix circuit 29 is output by the adder 27 to the output vertical high frequency signal and the adder 30. Addition and matrix circuit 2
9-bit luminance signal Y2 (y2) extracted from 9
With the output vertical high frequency signal of the adder 28 and the adder 31
Since the addition is added by the
Adders 30, 3 rather than a device for adding bit signals
1 can be simplified.

In the image signal processing device proposed by the present applicant, the vertical high-frequency components VH1 and VH1 are obtained by using the field memories 21 and 22 and the vertical high-pass filters 25 and 26.
Since H2 is obtained, there is a possibility that a correct vertical high frequency component cannot be obtained in the moving region. This problem is caused by a difference in image information between fields in a moving region. Therefore, the problem can be solved by determining the moving region and preventing the vertical high frequency component from being added to the final output luminance signal in that case. That is, in order to solve the above-mentioned problem, a determination circuit for determining a moving region and a selection means for selecting one of a signal to which a vertical high-frequency component is added and a signal not to be added based on the moving region determination signal are provided. The problem can be solved by providing it in the signal processing device.

The image signal processing apparatus proposed by the applicant of the present invention proposes, for example, a configuration shown in a block diagram of FIG. 7 as a moving area determination circuit. In the figure, a first low-pass filter (LPF) 41 for removing a high frequency component from a first input signal is provided, and a second low-pass filter (LPF) 41 is provided.
To remove the high frequency component from the output signal of the field memory 42, which delays the input signal of FIG.
, A low-pass filter (LPF) 43 is provided.
The subtracter 44 subtracts the output signals ID1 ″ and ID2 ″ of 1, 43 to obtain a difference. Since the LPFs 41 and 43 have a delay time, they also have the effect of horizontal interpolation, so that their frequency characteristics and their positions on the image can be matched.

The difference value extracted by the subtractor 44 is compared with a predetermined threshold value after its absolute value is calculated by a threshold circuit 45, and the comparison result is supplied to an area enlarging circuit 46. Is larger than the threshold value and is determined to be a moving area, a signal is obtained by expanding the area by a set width in the horizontal direction and the vertical direction, and this signal is a moving area determination signal M
It is output to the output terminal 47 as VD.

[0019]

However, in the image signal processing device proposed by the present applicant, the first luminance signals Y1 and y1 output from the matrix circuit 29 are:
As can be seen from equations (3) and (5), the R signal and the B signal
Two G signals are used as G signals to be matrix-operated together with the signals.
Solid-state imaging device 19G for one of the solid-state imaging devices for G
1, only the output G signals G1 and g1 are used. Similarly, the second luminance signals Y2 and y2 output from the matrix circuit 29 are R as shown in the equations (4) and (6). Since only the output G signals G2 and g2 of the other G solid-state imaging device 19G2 are used as a G signal to be matrix-operated together with the signal and the B signal, the characteristic difference between the G solid-state imaging devices 19G1 and 19G2, Due to the difference in gain and linearity of the output G signal in the analog signal processing unit, a direct current difference (DC difference) is generated in every other line of the HDTV image signal, and the image quality may be degraded.

In the image signal processing apparatus proposed by the present applicant, a moving area discriminating circuit as shown in FIG. 7 for discriminating a moving area is provided, and based on the moving area discriminating signal,
By providing a selection means for selecting one of a signal to which the vertical high frequency component is added and a signal not to be added in the image signal processing device, it is possible to solve a problem that a correct vertical high frequency component cannot be obtained in a moving region. However, even when the still region includes a slight vertical high-frequency component, the moving region determination signal is erroneously output, and image quality may be degraded due to erroneous detection of a still image.

That is, the solid-state imaging devices 19G1 and 19G1 shown in FIG.
9G2 is, for example, G1 (m, n), G2 (m,
n) or g1 (m, n) and g2 (m, n), they should be arranged at positions shifted by half a pixel in the vertical and horizontal directions. By
The arrangement of the solid-state imaging devices 19G1 and 19G2 is exactly 1 /
This is different from the position shifted by two pixels. Due to the error of the bonding position, the output of the subtractor 44 in FIG. 7 and the output of the subtractor 59 in FIG. 2 described later can be erroneously detected as a moving image region in the vertical high frequency region even in the case of a still image. There is.

The present invention has been made in view of the above points,
It is an object of the present invention to provide an image signal processing device capable of further improving image quality.

Another object of the present invention is to reduce adverse effects on image quality due to differences in characteristics between two G solid-state imaging devices and differences in gain and linearity of the output G signals in an analog signal processing unit. It is an object of the present invention to provide an image signal processing device capable of performing the above.

Still another object of the present invention is to provide an image signal processing device capable of preventing an adverse effect on image quality due to erroneous detection of a still image.

[0025]

In order to achieve the above-mentioned object, the present invention relates to a method for converting incident light into a first light consisting of blue light, a second light consisting of red light, and a third light consisting of green light. A color separation optical system for performing color separation on the fourth light, a first solid-state imaging device for blue light, into which the first light is incident, and outputs a blue light imaging signal, having a resolution of a standard television system; Second
A second solid-state image sensor for red light, which outputs a red light image signal upon incidence of light, has a standard television resolution, and a green light, on which third light is incident, outputs a green light image signal. A third solid-state imaging device for light, which has a resolution of a standard television system, and a fourth light is incident to output a green light imaging signal, and the pixel position of the third solid-state imaging device is the first solid-state imaging device. For green light, which is disposed so as to be displaced in the vertical direction relatively to the pixel position, and is displaced in at least one of the vertical direction and the horizontal direction with respect to the pixel position of the third solid-state imaging device. A first and second synthesizing means for synthesizing frames of output imaging signals of the first and second solid-state imaging devices, and a first and a second synthesizing means. 2 from the output frame composite signal of the composite means Extracting means for extracting first and second high-frequency signals of different directions, and a color difference signal and first and second luminance signals based on imaging signals respectively taken out of the first to fourth solid-state imaging devices. The first and second luminance signals are generated, and a matrix circuit is generated by performing a matrix operation using all of the imaging signals extracted from the first to fourth solid-state imaging devices. A third synthesizing unit for synthesizing the first high frequency signal from the extracting unit with the obtained first luminance signal, and a second synthesizing signal output from the matrix circuit,
Fourth combining means for combining the second high frequency signal from the extracting means, and the first luminance signal output from the matrix circuit and the combined signal from the third combining means alternately for each field. A configuration including first selecting means for selecting, and second selecting means for alternately selecting, on a field-by-field basis, the second luminance signal output from the matrix circuit and the synthesized signal from the fourth synthesizing means; It was done.

In the present invention, each of the first and second luminance signals generated by the matrix circuit is generated by a matrix operation using all of the image pickup signals respectively extracted from the first to fourth solid-state image pickup devices. Because
Even if there are differences in the characteristics of the third and fourth solid-state imaging devices and differences in the gain and linearity of the output imaging signals in the analog signal processing unit, the difference between the Hi-Vision image signals of every other line caused by these differences. The DC difference can be averaged.

According to another aspect of the present invention, there is provided a delay unit that sets output image signals of the third and fourth solid-state image sensors to image signals different from each other by one field, and a delay unit. First and second filter means for separately removing a horizontal high frequency component and a vertical high frequency component for two image signals different from each other by one field, and two image signals different from each other by one field obtained by a delay means Third filter means for removing a horizontal high frequency component and a vertical low frequency component from one of the imaging signals of the signal, and difference means for obtaining a difference value of each signal extracted from the first and second filter means A first comparison means for comparing the output difference value of the difference means with a first threshold value to obtain a first comparison result, and an output signal of the third filter means as a second threshold value. A second comparison means for obtaining a second comparison result by performing a small comparison, and a logical operation of output signals of the first and second comparison means to obtain an imaging signal in a moving area and a vertical low-frequency area. And a logic circuit for generating a moving area discrimination signal having a logical value different from that of the other area, and activating the synthesizing operation of the first high frequency signal to the first luminance signal by the third synthesizing means. First limiting means for restricting a moving area on the basis of the area determining signal and at the time of vertical low-frequency area determination, and a synthesizing operation of the second high frequency signal to the second luminance signal by the fourth synthesizing means. And a second restricting means for restricting at the time of vertical low frequency region determination based on the moving region determination signal.

According to the present invention, the difference value of the two-dimensional low-pass filter is extracted from the difference means, and the first comparison means can obtain a first comparison result indicating whether the imaging signal is a moving area or a stationary area. , The second comparison means can obtain a second comparison result indicating whether the imaging signal is a signal in the vertical high-frequency area or a signal in the vertical low-frequency area, and obtain a moving area discrimination signal based on both of the comparison results. be able to.

[0029]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of a main part of an image signal processing apparatus according to the present invention. 6, the same components as those of FIG. 6 are denoted by the same reference numerals, and the description thereof will be omitted. This embodiment has a color separation optical system as shown in FIG. 4, and the pixel position on the high-vision screen of the solid-state imaging device as shown in FIG. 5 is different from the image signal proposed by the present applicant. This is the same as the processing device, except that the image signal processing circuit has a configuration as shown in FIG. Here, the image signal processing circuit of this embodiment has a circuit configuration substantially similar to that of the image signal processing circuit shown in FIG.

That is, the matrix circuit 51 outputs input digital signals (pixel data) DB, DR, DG1 of 10 bits each output from the color separation optical system shown in FIG. 4 and obtained by A / D conversion. DG2 is received as an input signal, and 8-bit luminance signals Y1, Y2, y1 and y2 are generated by a matrix operation of the following equations (13) to (16). 8-bit color difference signals (RY), (BY), (ry) and (b)
-Y). Here, as described above, uppercase letters are signals in odd fields, and lowercase letters are signals in even fields.

Y1m, n = 0.701 {(G1m, n) / 2 + (G2m, n + G2m + 1, n) / 4} + {0.212 (Rm, n + Rm + 1, n) / 2} +0.087 (Bm, n + Bm + 1, n) / 2 (13) Y2m, n = 0.701 {(G2m, n) / 2 + (G1m-1, n + Gm, n) / 4} + 0.212Rm, n + 0.087Bm, n (14) y1m, n = 0.701 {(g1m, n) / 2 + (g2m, n + g2m + 1, n) / 4} + {0.212 (rm, n + rm + 1, n) / 2} +0.087 (bm, n + bm + 1, n) / 2 (15) y2m, n = 0.701 {(g2m, n) / 2 + (g1m-1, n + g1m, n) / 4} +0.212 rm, n + 0.087bm, n (16) (RY) m, n = Rm, n-Y2m, n (17) (BY) m, n = Bm, n-Y2m, n (18) ( (ry) m, n = rm, ny2m, n (19) (by) m, n = bm, ny2m, n (20) As shown in equation (13), n of the odd field The first luminance signal Y1m, n in the m pixels of the line is a G signal used in the matrix operation together with the R signal and the signal, and the pixel value G1m, n of the G solid-state imaging device 19G1 of the target pixel (m, n). To 1 / A value obtained by adding 1/4 times the sum of the pixel value G2m, n of the G solid-state imaging device 19G2 of the target pixel (m, n) and the value G2m + 1, n of the adjacent pixel is added to the doubled value. And a signal multiplied by a predetermined coefficient.

That is, the pixel values G1m, n and G2m, n of the target pixel (m, n) of the G solid-state imaging devices 19G1 and 19G2 driven at the same time, and one of these pixels is horizontally adjacent to the pixel. A matrix operation is performed using the value G2m + 1, n or G1m-1, n of one pixel to generate Y1m, n, Y2m, n. The same applies to the other luminance signals Y2m, n, y1m, n, y2m, n.

As described above, in this embodiment, the first luminance signals Y1 and y1 and the second luminance signals Y2 and y which are obtained by performing a matrix operation from the matrix circuit 51 are taken out.
2 is a G signal to be matrix-processed together with the R signal and the B signal, as can be seen from Expressions (13) to (16).
Output image data G1 (g1) and G2 (g2) of both the two G solid-state imaging devices 19G1 and 19G2 are used. Therefore, the G solid-state imaging devices 19G1 and 19G2
Even if there is a difference in the characteristics of the above or a difference in the gain or linearity of the output G signal in the analog signal processing unit, the DC difference of the Hi-Vision image signal of every other line caused by these differences is averaged, The image quality can be improved as compared with the image signal processing device proposed by the present applicant.

Next, another embodiment of the present invention will be described. FIG. 2 is a circuit diagram of another embodiment of the image signal processing apparatus according to the present invention. In the embodiment shown in FIG. 1, similarly to the image signal processing apparatus proposed by the present applicant, the vertical high-frequency component VH is used by using the field memories 21 and 22 and the vertical high-pass filters 25 and 26.
1, since VH2 is obtained, there is a possibility that a correct vertical high-frequency component cannot be obtained in the moving region as described above. In order to solve this problem, a moving region discriminating circuit for discriminating a moving region and a selecting means for selecting one of a signal to which a vertical high frequency component is added and a signal not to be added based on the moving region discriminating signal are provided by an image signal. The problem can be solved by providing it in the processing device.

FIG. 2 is a circuit diagram of an embodiment of the above-mentioned moving region discriminating circuit according to the present invention, in which the output green signals of the G solid-state image pickup devices 19G1 and 19G2 are A / D-converted.
One of the G pixel data DG1 and DG2 obtained by the conversion is supplied to a horizontal low-pass filter (LPF) 53 as a first input signal, and a horizontal low-frequency component is filtered. The vertical LPF 54 and the vertical high-pass filter (HPF) 55 are supplied to the vertical LPF 54 and the vertical high-pass filter 55, respectively.

After the other of the G pixel data DG1 and DG2 is supplied to the field memory 56 and is delayed by almost one field, the horizontal LPF 57
And the high frequency components in the horizontal and vertical directions are removed through the vertical LPF 58 and the vertical LPF 58, respectively. The subtractor 59 has a vertical L
One of the G pixel data from which the horizontal and vertical high frequency components from the PF 54 have been removed, and the horizontal and vertical high frequency components from the vertical LPF 58 have been removed, and the signal has been delayed by almost one field. A difference value from the other G pixel data is calculated.

The difference value extracted from the subtractor 59 is compared with a predetermined threshold value after an absolute value is obtained by a threshold circuit 60. If the difference value is larger than the threshold value, it is determined that the region is a moving area. Then, the result of the determination is supplied to the area enlargement circuit 61. In the case of a moving area, a signal of logic "1" obtained by expanding the area by a set width in the horizontal direction and the vertical direction, respectively, Is done. When the absolute value of the difference value is equal to or smaller than the threshold value, it is determined that the area is a static area, and a signal of logic “0” is output from the area enlarging circuit 61.

However, since the output signal of the area enlargement circuit 61 (hereinafter referred to as a) is based on the result of comparing the difference between the signals passed through the vertical LPFs 54 and 58 and the threshold value, the input signal DG1 , DG2 indicate whether the vertical low-frequency region is a moving region or a stationary region.

On the other hand, the signal extracted from the vertical HPF 55 is a signal in the vertical high-frequency region, and after its absolute value is calculated by the threshold circuit 62, is compared with a predetermined threshold value. When the signal is determined to be a signal in the vertical high frequency region and is set to logic "1", when the signal is equal to or less than the threshold value, it is determined to be a signal in the vertical low frequency region and is set to a signal of logic "0". After being inverted at 63, the signal is supplied to the area enlarging circuit 64. Here, in the case of the vertical high frequency area, the signal is a logical "0" signal obtained by expanding the area in the horizontal and vertical directions by the set width.

Here, the output signal of the area enlarging circuit 64 (referred to as b) is based on the result of the magnitude comparison between the signal passing through the vertical HPF 55 and the threshold, and therefore the vertical height of the input signal DG1 or DG2 is obtained. It indicates whether the signal is a signal in the band region or a signal in the vertical low band region. Therefore, in the case of a signal having many vertical high frequency components, the logic of the output signal b of the area enlarging circuit 64 becomes “0”.

The output signal a of the above-described area enlargement circuit 61 and the output signal b of the area enlargement circuit 64 are each a two-input AND
The signal c, which is supplied to the circuit 65 and obtained by performing a logical product operation, is output to the output terminal 66 as the moving area determination signal MVD. The following table summarizes the relationship among the output signals a, b, and c.

[0042]

[Table 1] Therefore, in the case of a signal having many vertical high-frequency components even in a stationary area, in this embodiment, the output signal b becomes logic “0”, so that the output signal c of the AND circuit 65 (the moving area determination signal MVD) becomes logic "0", which can prevent the conventional erroneous detection. Since the horizontal LPFs 53 and 57 have a delay time, they also have the effect of horizontal interpolation, so that their frequency characteristics and their positions on the image can be matched.

A luminance signal processing circuit for selecting one of a signal to which the vertical high frequency component is added and a signal not to be added based on the output moving region discriminating signal c (MVD) of the moving region discriminating circuit,
The same luminance signal processing circuit as that used in the image signal processing device proposed by the present applicant, for example, shown in the block diagram of FIG. 3, can be used.

In the figure, input terminals 70 and 71 are luminance signal or image signal input terminals, and when applied to the embodiment of FIG. 1, the output luminance signal Y of the matrix circuit 29 is used.
1 (y1) and Y2 (y2). Also, input terminals 72 and 73 in FIG. 3 are vertical high frequency signal VH1 and VH2 input terminals, and output vertical high frequency signals VH1 and VH2 of the adders 27 and 28 in FIG. The input terminal 74 in FIG. 3 receives the field pulse input terminal, and the input terminal 75 receives the moving region discrimination signal MVD output from the moving region discriminating circuit shown in FIG. Further, the adders 76 and 77 in FIG.
Correspond to the adders 30 and 31 in FIG. 1, and the changeover switches 80 and 81 in FIG. 3 correspond to the changeover switches 32 and 33 in FIG. As described above, the embodiment of FIG. 3 is provided with the changeover switches 78 and 79 in the embodiment of FIG.

In this embodiment, the moving area discrimination signal MVD input to the input terminal 75 is supplied to the changeover switches 78 and 7
9 is applied as a switching signal. Normally, the changeover switches 78 and 79 are respectively connected to the terminals a and the vertical high frequency signal V input through the input terminals 72 and 73 is input.
H1 and VH2 are selected and supplied to the adders 76 and 77. When the moving area discrimination signal MVD is the moving area and the logical value "1" indicating the vertical low band area, the changeover switches 78 and 79 are set. The terminals are switched to the terminal b side, and the supply of the vertical high frequency signals VH1 and VH2 input through the input terminals 72 and 73 to the adders 76 and 77 is forcibly cut off.

As a result, the output terminals 82 and 83
The final output luminance signal output to the double speed conversion circuit 34 of
In the moving region, the vertical high frequency signals VH1 and VH2 can be prevented from being added, and the image quality can be prevented from deteriorating.
Further, in this embodiment, as shown in Table 1, even in the moving region, when the vertical high frequency is large, the moving region determination signal MVD (c) has the logical value “0”. In this case, the vertical high frequency signals VH1 and VH2 are selected by the changeover switches 78 and 79 and supplied to the adders 76 and 77.

The present invention is not limited to the above embodiment. For example, in the matrix operation of the matrix circuit 51 shown in FIG. 1, an operation using a higher-order pixel component in the horizontal direction may be used. Good (eg, Ym, n is G1
m, n, G2m, n, G2m + 1, n as well as G1m-1, n, G1
or using m + 1, n). The solid-state imaging device used is not a solid-state imaging device for the PAL system,
A solid-state image pickup device of another standard television system such as the SC system can also be used.

The present invention is not limited to the image pickup apparatus having the pixel arrangement shown in FIG. 5, but may be shifted by one pixel pitch in the vertical direction, for example, as in the image pickup apparatus proposed by the present applicant.
In addition, two solid-state imaging devices for G, which are shifted by a half pixel pitch in the horizontal direction, are prepared. The present invention can also be applied to an image pickup apparatus having a color separation optical system using a total of four solid state image pickup elements in which B and R solid state image pickup elements shifted by one pixel pitch in the direction are arranged.
In this case, the pixel position of the R signal in one of the odd and even fields is superimposed on the pixel position of the B signal in the other field.

[0049]

As described above, according to the present invention,
By generating each of the first and second luminance signals generated by the matrix circuit by a matrix operation using all of the imaging signals respectively taken out of the first to fourth solid-state imaging elements, the third and third luminance signals are generated. Even if there are differences in the characteristics of the solid-state imaging device of No. 4 and differences in the gain and linearity of the output imaging signal in the analog signal processing unit, the DC difference of the Hi-Vision image signal for every other line caused by these differences is averaged. Therefore, the image quality can be improved as compared with a conventional apparatus in which a DC difference occurs between the high-vision image signals of every other line.

Further, according to the present invention, the first comparison result indicating whether the imaging signal is a moving area or a stationary area, and the second comparison result indicating whether the imaging signal is a signal in a vertical high-frequency area or a signal in a vertical low-frequency area. To obtain a moving region discrimination signal based on the comparison result of
The presence of a slight vertical high-frequency component in the stationary region does not erroneously determine the moving region, and the moving region can be determined.
By preventing the vertical high frequency component from being added to the final output luminance signal when a moving area is determined based on the moving area determination signal, it is possible to achieve both prevention of image quality deterioration.

[Brief description of the drawings]

FIG. 1 is a block diagram of an embodiment of a main part of the present invention.

FIG. 2 is a circuit diagram of an embodiment of another main part of the present invention.

FIG. 3 is a block diagram of an example of a luminance signal processing circuit used in an image signal processing device proposed by the present applicant.

FIG. 4 is a diagram showing an example of a color separation optical system proposed by the present applicant and applied to an embodiment of the present invention.

FIG. 5 is a diagram illustrating an example of a pixel position on a high-definition screen of a solid-state imaging device of an image signal processing device proposed by the present applicant and applied to an embodiment of the present invention;

FIG. 6 is a block diagram showing an example of a main part of an image signal processing device proposed by the present applicant.

FIG. 7 is a block diagram illustrating an example of another main part of the image signal processing device proposed by the present applicant.

[Explanation of symbols]

19B Solid-state image sensor for blue light (first fixed image sensor) 19R Solid-state image sensor for red light (second fixed image sensor) 19G1, 19G2 Solid-state image sensor for green light (third and fourth fixed image sensors) 21, 22 field memory 23 frame combining circuit (first combining means) 24 frame combining circuit (second combining means) 25, 26 vertical high-pass filter (extracting means) 27, 28 adder 30 adder (first Combining means) 31 adder (second combining means) 32 changeover switch (first selecting means) 33 changeover switch (second selecting means) 34 double speed conversion circuit 51 matrix circuit 53 horizontal low-pass filter (LPF) (second 54, 58 vertical low-pass filter (LPF) (first, second filter means)
55 Vertical high-pass filter (HPF) (third filter means) 56 Field memory (delay means) 57 Horizontal low-pass filter (LPF) (second filter means) 59 Subtractor (difference means) 60 62 threshold circuit (first and second comparing means) 61, 64 area expanding circuit 63 inverter (second comparing means) 65 AND circuit (logic circuit) 66 moving area determination signal output terminal

Claims (4)

[Claims] 1. Incident light is a first light consisting of blue light, a second light consisting of red light, and a third and fourth light consisting of green light.
A first solid-state imaging device for blue light, into which the first light is incident and outputs an imaging signal of blue light, having a resolution of a standard television system; and A second solid-state image sensor for red light, which receives a second light and outputs a red light image signal, and has a resolution of a standard television system; and a green light image signal to which the third light is incident. A third solid-state imaging device for green light to be output and having a resolution of a standard television system, and the fourth light is incident thereon to output an imaging signal of green light, and the pixel position is set to the first and second pixels. Is arranged so as to be shifted in the vertical direction relatively to the pixel position of the solid-state imaging device, and is shifted at least in one direction in the vertical direction and the horizontal direction with respect to the pixel position of the third solid-state imaging device. Standard TV with placed green light A fourth solid-state imaging device having a resolution of a John system, first and second combining means for combining frames of output imaging signals of the first and second solid-state imaging devices, and the first and second combining devices. Extracting means for extracting first and second high-frequency signals in the vertical direction from an output frame synthesized signal of the synthesizing means; and Signal and first and second luminance signals, and each of the first and second luminance signals is a matrix using all of the imaging signals extracted from the first to fourth solid-state imaging devices. A matrix circuit generated by calculation, and a first luminance signal output from the matrix circuit,
A third synthesizing unit for synthesizing a first high frequency signal from the extracting unit, and a second luminance signal output from the matrix circuit,
A fourth synthesizing unit for synthesizing the second high frequency signal from the extracting unit, and a first luminance signal output from the matrix circuit and a synthesized signal from the third synthesizing unit for each field. First selecting means for alternately selecting the second luminance signal output from the matrix circuit and the synthesized signal from the fourth synthesizing means alternately for each field. An image signal processing device comprising: 2. A pixel position of the third solid-state imaging device,
The pixel positions of the fourth solid-state image sensor are vertically shifted by one pixel pitch in the vertical direction, and are shifted by 1/2 pixel pitch in the horizontal direction.
The pixel position of the solid-state imaging device is shifted by a half pixel pitch in the vertical direction relative to one of the pixel positions of the third and fourth solid-state imaging devices. 2. The image signal processing device according to 1. 3. The matrix circuit comprises: a first pixel and a second pixel which are each one pixel driven by the third and fourth solid-state imaging devices at the same time; And a matrix operation between the imaging signals of one or more pixels horizontally adjacent to at least one of the second pixels and the output imaging signals of the first and second solid-state imaging devices, 3. The image signal processing apparatus according to claim 1, wherein each of the first and second luminance signals is generated. 4. A delay means for setting each output image signal of the third and fourth solid-state image sensors to an image signal different from each other by one field, and two image signals different from each other by one field obtained by the delay means. And first and second filter means for separately removing the horizontal high frequency component and the vertical high frequency component, and the horizontal height of one of the two image signals obtained by the delay means and which differs from each other by one field. Third filter means for removing a band frequency component and a vertical low frequency component, difference means for obtaining a difference value of each signal extracted from the first and second filter means, and output difference of the difference means A first comparing means for comparing the value with a first threshold to obtain a first comparison result, and a second comparing means for comparing the output signal of the third filter with a second threshold to obtain a second comparison result. Second comparing means for obtaining a comparison result;
A logical operation is performed on the output signals of the first and second comparing means, and a dynamic region having a different logical value between the case where the imaging signal is a dynamic region and a vertical low-frequency region and the other region. A logic circuit for generating a discrimination signal, and synthesizing the first high frequency signal to the first luminance signal by the third synthesizing unit in the moving area based on the moving area discrimination signal; and A first restricting means for restricting the vertical low-frequency region discrimination, and a synthesizing operation of the second high-frequency signal to the second luminance signal by the fourth synthesizing unit based on the moving-region discriminating signal. 3. The image signal processing apparatus according to claim 1, further comprising a second limiting unit that limits the moving area and the vertical low-frequency area.