JPH06319145A - Color television camera equipment - Google Patents

Abstract

PURPOSE:To enhance clearly the effect of the picture element shift image pickup method even under any condition by comparing luminance information of a valid picture element of other color arranged in an interpolated position of each color with a mean value of luminance information of a valid picture element of a concerned color at both sides of the interpolated position and using the information which has a smaller level for the luminance information of the interpolated position of the concerned color. CONSTITUTION:The equipment is provided with CCD 31-33 as three color image pickup elements of red, blue and green which are arranged respectively at three position of a real image formed in an image pickup section 1. Valid picture elements of the CCD 31, 32 for two colors (red and blue) in the CCD 31-33 are located at a common position and the valid picture element of the green CCD 33 is arranged at an interpolation position where the valid picture elements of the CCD 31, 32 is not in existence. Then a picture signal interpolation circuit 5 compares luminance information of the valid picture elements of other color arranged at an interpolated position of each color with a mean value of the luminance information of a valid picture element of a concerned color at both sides of the luminance information as the luminance information of the color at the interpolated position having no valid picture element of each color to use the information which has a smaller level for the luminance information of the interpolated position.

Description

Detailed Description of the Invention

[0001]

The present invention is used in television systems. In particular, spatial pixel shift imaging method (written by Seisuke Yamanaka, 3C)
CD color camera system, Television Society Technical Report, September 28, 1978, see) Interpolation technology.

[0002]

2. Description of the Related Art Recently, CCDs have been used for television image pickup devices.
Is widely used. This is a semiconductor in which light receiving portions for generating a signal which becomes a pixel which is a minimum unit constituting a screen are arranged in a grid pattern and processed so as to obtain a necessary number of pixels as a whole. However, in some cases, the currently available C
In some cases, a higher resolution than that of a CD is required.
An imaging method considered based on such a demand is the spatial pixel shift imaging method described above.

A conventional example will be described with reference to FIGS. 4 and 5. FIG. 4 is a configuration diagram of an image pickup unit in the color television camera device. FIG. 5 is a diagram for explaining the spatial pixel shift imaging method. A color television camera device requires three primary color signals of red (R), green (G) and blue (B). In order to realize this, as shown in FIG. 4, the three CCDs 31 to 33 are fixed to the color separation prism 30 so as to be in predetermined positions. At this time, in order to obtain a resolution equal to or larger than the number of pixels possessed by the CCDs 31 to 33, a spatial shift imaging method has been proposed. Usually three CCDs as shown in FIG.
Pixels of (R, G, B) 31 to 33 respectively correspond to the same point of the image of the subject. In the spatial shift imaging method, FIG.
As shown in (b), the CCDs (R, B) 31 and 32 are arranged at standard positions, but the CCD (G) 33 is constructed by shifting the pixel pitch by ½ pitch. With this configuration, the number of pixels is equivalently doubled in the vertical direction.

When the pixels are arranged as shown in FIG. 5B, although the CCDs (R, G, B) 31 to 33 are originally arranged to express one color, the CCDs (R, B) 31, 32 are arranged. The green signal is missing in the part of the image of the subject corresponding to
The red and blue signals are missing in the portion of the image of the subject corresponding to D (G) 33. In order to interpolate these, FIG.
For the interpolation signal '(R, B) in (b), ′ = (+) / 2 is adopted, and for the interpolation signal ′ (G) in FIG. 5 (b), ′ = (+) / 2 is adopted. And interpolation is performed.

[0005]

However, the condition of the subject to which the spatially-shifted imaging method is applied is limited to an achromatic color or one having a low color saturation. In addition, even in the case of an achromatic subject, for example, when a striped pattern is imaged, the CCD red,
If there is a white part in the part sensitive to blue and a black part in the part sensitive to green, a signal is generated in all the red and blue parts, and the signal in the green part becomes zero. It becomes magenta as the sum of blue and cannot reproduce the striped pattern.

The present invention has been made against such a background, and an object of the present invention is to provide a color television camera device capable of clearly exhibiting the effect of the pixel shift imaging method under any conditions.

[0007]

SUMMARY OF THE INVENTION The present invention comprises three color image pickup devices, one for each color, at three positions where a real image is formed. The three color image pickup devices are effective for two colors. The pixels are arranged at a common position, and for the other one color, the effective pixel is arranged so as to be an interpolation position where there are no effective pixels of the two colors, and the interpolation is performed as the luminance information of the color at the interpolation position where there is no effective pixel of each color. The color television camera device is provided with means for calculating the average value of the luminance information of the effective pixels of that color on both sides of the position.

Here, the feature of the present invention is that the luminance information of effective pixels of other colors arranged at the interpolation positions of each color and the average value of the luminance information of the effective pixels of the own color on both sides of the interpolation positions. And a processing means for making the one having a smaller level the luminance information of the interpolation position of the color.

The processing means may be provided in a box separate from the optical system. Further, it may be configured to include means for performing the interpolation by designating a part of the screen.

[0010]

In addition to interpolating the signal of the part where the pixel of the image pickup device does not exist with the signal value of the pixel on the image pickup device, the signal value of the pixel of another image pickup device corresponding to the part where the image pickup device does not actually exist is also included. Interpolation. If the lower level is taken, the levels will be different from both sides and a striped pattern will appear.

As a result, the effect of the spatial pixel shift imaging method can be clearly exhibited under any condition.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a block diagram of an apparatus according to an embodiment of the present invention.

The present invention is provided with CCDs 31 to 33 as red, blue and green three-color image pickup elements arranged in three colors, respectively, at three positions where a real image of the image pickup section 1 is formed.
33 is arranged such that the effective pixels of the red and blue two-color CCDs 31 and 32 are at the common position, and the effective pixels of the green CCD 33 are at the interpolation positions where there are no effective pixels of the CCDs 31 and 32. The image signal interpolation circuit 5 is provided in the image signal processing unit 3 as a means for calculating the average value of the luminance information of the effective pixels of the color on both sides of the interpolation position as the luminance information of the color at the interpolation position having no effective pixel of It is a color TV camera device.

Here, the feature of the present invention is that the luminance information of effective pixels of other colors arranged at the interpolation positions of each color and the average value of the luminance information of the effective pixels of the own color on both sides of the interpolation positions. The image signal interpolating circuit 5 is provided with a processing means for comparing the above-mentioned values with the one having the smaller level as the luminance information of the interpolation position of the color.

Next, the operation of the embodiment of the present invention will be described with reference to FIGS. FIG. 2 is a diagram showing a state in which a striped pattern is projected on a pixel arrangement by the spatial pixel shift imaging method. FIG. 3 is a diagram for explaining the operation of the embodiment of the present invention. The striped pattern shown in FIG. 2 (a) is projected as shown in FIG. 2 (c) just on the pixel arrangement shown in FIG. 2 (b). That is, all pixels in the CCD that are sensitive to red and blue are black, and all pixels that are sensitive to green are white. If the interpolation in the above-described conventional example is applied to this, a uniform color is obtained over the entire surface, and the original black and white striped pattern cannot be expressed. Therefore,
The present invention has been devised so that a black and white striped pattern can be expressed even in such a case.

In FIG. 3, pixels surrounded by solid lines are existing pixels, and pixels surrounded by broken lines are virtual pixels obtained by interpolation. Although FIG. 3A and FIG. 3B actually overlap each other, they are shown separately on the left and right sides for the sake of clarity. Thus, a green sensitive pixel corresponds to a virtual pixel portion of a red and blue sensitive pixel, and a red and blue sensitive pixel corresponds to a virtual pixel portion of a green sensitive pixel. The interpolation signal in the present invention is adopted as follows: '= min [(+) / 2 | signal]' = min [(+) / 2 | signal] That is, the interpolated signal corresponding to the'part is the signal obtained by (+) / 2 as the average value of the pixels sensitive to red and blue described in the conventional example and the signal of the pixel sensitive to green. The one with the smaller level is adopted as the interpolation signal.
Thus, in the conventional interpolation method, red and blue are all black and green is all white, but according to the present invention, the green interpolation signal is black. Therefore, since the portion of the pixel sensitive to green shown in FIG. 3B is white, black, white, black, ..., It can be identified that the subject has a striped pattern.

With respect to the signal of the pixel sensitive to blue, since blue is a luminance signal and has little visual effect, there is no practical problem even if only the interpolation described in the conventional example is performed.

In the embodiment of the present invention, the interpolation is performed inside the color television camera device, but R, B and G are used.
It may be performed after the signal is transmitted to a remote place. Further, it is not necessary to perform it for all the areas of the screen, and it is also possible to specify a required portion.

[0019]

As described above, according to the present invention,
The effect of the pixel shift imaging method can be clearly exhibited under any conditions. According to the present invention, it is possible to avoid a phenomenon in which a striped pattern is masked and becomes uniform gray.

[Brief description of drawings]

FIG. 1 is a block configuration diagram of an apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram showing a state in which a striped pattern is projected on a pixel arrangement by a spatial pixel shift method.

FIG. 3 is a diagram for explaining the operation of the embodiment of the present invention.

FIG. 4 is a configuration diagram of an imaging unit in the color television camera device.

FIG. 5 is a diagram illustrating a spatial pixel shift imaging method.

[Explanation of symbols]

 1 Imaging Unit 3 Image Signal Processing Unit 5 Image Signal Interpolation Circuit 30 Color Separation Prism 31-33 CCD

Claims (3)

[Claims] 1. A three-color image pickup device, in which one color is arranged at each of three positions where a real image is formed, is provided, and in the three-color image pickup device, effective pixels of two colors are at a common position, and For one color, the effective pixel is arranged so as to be the interpolation position where there are no effective pixels for the two colors, and as the luminance information of that color at the interpolation position where there is no effective pixel for each color, the effective values for that color on both sides of that interpolation position are used. In a color television camera device equipped with a means for calculating an average value of luminance information of pixels, luminance information of effective pixels of other colors arranged at interpolation positions of respective colors and luminance of effective pixels of own color on both sides of the interpolation positions. A color television camera device comprising a processing means for comparing the average value of information with the one having a smaller level as luminance information of the interpolation position of the color. 2. The color television camera device according to claim 1, wherein the processing means is provided in a box separate from the optical system. 3. The color television camera device according to claim 1, further comprising means for performing the interpolation by designating a part of a screen.