JPH02250468A - Image pickup device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a television camera that can reduce image shaking caused by camera shake when photographing television images.

[Conventional technology]

Currently, zoom operations on TV cameras are performed using a zoom lens (TV Society Technical Report Vol. 1.12.Nα41゜P
7 (TEBS″88-27)).

However, lenses that provide a large zoom ratio are large and heavy, making them difficult to handle and prone to camera shake.

Furthermore, when the image is enlarged, even the slightest vibration is greatly magnified, so the projected image tends to move up and down significantly, resulting in a poor-quality image that is very difficult to see.

[Problem to be solved by the invention]

The present invention provides an imaging device that can reduce shaking due to camera shake, etc., not only in the enlarged image but also in the same size or reduced size image.

[Means to solve the problem]

In order to achieve the above object, in the present invention, a part of the zoom operation is performed electrically, that is, a signal from a specified range of area (hereinafter referred to as specified area) on the light receiving surface of the image sensor is used for image output. The video signal is reconfigured and output. On the other hand, the movement of an image within a certain area of the captured video (which does not need to be within the specified area) is detected, and the specified area is Make the position move.

[Effect]

In the present invention, the position of the area to be imaged on the light-receiving surface moves in accordance with the movement of the target image, such as the image portion to be imaged. Therefore, the position of the output image can be almost fixed on the screen, and a good output video signal with less image shaking can be obtained.

〔Example〕

A first embodiment of the present invention using a solid-state image sensor as the image sensor is shown in FIG.

FIG. 2(a) schematically shows the structure of a normal CCDC solid-state image sensor, in which numeral 10 is a photodiode that converts incident light into an electrical signal, and numeral 11 is a photodiode that converts the signal charge converted by the photodiode 10 into an electrical signal in a vertical direction. vertical CCL), 1
Reference numeral 2 denotes a horizontal CCL which further carries the signal charge carried by the vertical ccLJ to the output circuit 13.

By the way, in television signals (N'rSC system, etc.), interlace operation is generally performed, and even-numbered lines out of all the horizontal scanning lines (hereinafter simply referred to as lines) scanned in the Saturday frame period are scanned in the first field period. , and the odd numbered line as the second
Scan the field period. In a solid-state image sensor such as a CCD type, normally the image sensor shown in Fig. 3 (
As schematically shown in a), two consecutive lines of signal charges whose combinations are changed for each field are combined into one, and the sum signal is output.

On the other hand, the circuit shown in Figure 1 has a structure that allows all the signals of all pixels to be read out independently for each field, as shown in Figure 3 (b), in order to reduce resolution deterioration due to image enlargement processing, which will be described later. A solid-state image sensor is used. Such a solid-state image sensor, for example, doubles the number of CCDs 11 in the vertical direction of the normal CCD type image sensor shown in FIG. 2(a), as shown in FIG. Improvements have been made such as the provision of two lines, 12 and 12', so that twice the number of signals that can be read out in one field period can be read out (the signals of all pixels can be read out independently). obtained by doing.

In the circuit shown in FIG. 1, an optical signal passing through an optical lens is converted into an electrical signal at each pixel of the solid-state image sensor l. Even in an enlarged video signal in which the signals of all pixels are sequentially and independently read out during one field, signals of the same number of horizontal lines as the television signal is required. However, if you enlarge the image taken with the circumferential image sensor, the distance between the horizontal lines where light is detected will also be enlarged, so the fourth
As shown in the figure, the line position of the output signal deviates from the horizontal line position required for the enlarged image and the number of lines decreases. Therefore, the signal level at the line position required for the TV signal for the enlarged image It is necessary to find it by interpolation.

Therefore, the signal read from the solid-state image sensor 1 is first stored in the auxiliary memory 3 in the video storage circuit 2, and then stored in the interpolation circuit 4.
Enter. Then, a video signal at a required line position is obtained by interpolation using the signals of M×N pixels in the vicinity (signals in the auxiliary memory 3), and an enlarged one-field video signal is constructed.

For example, in the case of doubling magnification, in the first field, the signals of each line read from the image sensor are made to correspond to the video signals of one horizontal period as shown in the fifth field on the left, and
Configure the field video signal. - In the 2-field power cylinder, for interlacing operation, the signals of two consecutive lines are averaged as shown in the 5th figure on the right, and each of the average signals is made to correspond to the video signal of one horizontal period to generate the video signal of one field. Configure. The video signal thus configured is then manually converted into a television signal by the signal processing circuit 5, and output as an enlarged television signal.

On the other hand, the field memory 6, motion amount detection circuit 7, and enlargement position designation circuit 8 in the video storage circuit 2 shown in FIG. 1 are circuits provided to reduce the movement of the enlarged image. That is, part of the signal outputted by the solid-state image sensor 1 is sequentially stored in the field memory 6 in preparation for the following signal processing to be performed in the next field. At the same time, motion amount detection [! ! The circuit 7 compares the signal from the previous field, which is already stored in the field memory 6, with the signal output from the solid-state image sensor 1, and generates an image of a part of the image (a specified area specified by the enlargement position specifying circuit). For example, the amount and direction of movement of the image near the center of the specified area are detected. Then, so that the movement of the image within the specified area is small,
The position d of the specified area specified by the enlarged position specifying circuit 8 is moved in accordance with the detected movement foot and direction.

In this way, in this imaging device, the position of the area to be enlarged can be moved in accordance with the movement of the image within the specified area, and the movement of the image within the specified area can be reduced. Therefore, the position of the enlarged image can be kept almost stationary on the screen, and a good enlarged image with less image shaking can be obtained. Furthermore, the conventional method of adjusting the zoom ratio using the mechanical mechanism of the lens allows the zoom ratio to be changed only at a relatively slow speed. As a result, it was not possible to meet the demands of photographers who wanted to zoom in on parts of the footage all at once. In contrast, in this method, the enlargement or reduction operation is performed electrically, making it possible to meet the severe demands of photographers.

Also, for example, in the finder of a handy camera, etc., the first
As exemplified in image 9 in the figure, the unenlarged image and the enlarged image can be output simultaneously or in chronological order by switching with a switch or the like, or the specified area position or motion detection position can be further aligned with the unenlarged image. By adding functions such as displaying images, it is possible to easily take pictures when zooming up.

Alternatively, a detection circuit for the zoom ratio of the zoom lens is newly provided in the imaging apparatus according to the present embodiment, and the zoom ratio of the lens and the electrical magnification for the designated area are changed in conjunction with each other based on this detection signal.

Furthermore, a magnification control circuit is provided so that, for example, even if the zoom ratio of a zoom lens is changed, the magnification of the output television signal does not change. If you add new functions like this and increase the zoom ratio of the lens.

Conversely, since the electrical magnification becomes smaller, the resolution of the enlarged image can be increased. By utilizing this function and adjusting the zoom ratio of the zoom lens in accordance with the resolution of the enlarged image and the amount of image shaking due to camera shake, etc., a good enlarged image can be obtained. Needless to say, it is desirable to adjust the zoom ratio automatically at this time.

FIG. 6 shows a second embodiment of the present invention. In this embodiment,
Processing is almost the same as in the first embodiment, except that the conventional solid-state image sensor 1' shown in FIG. If the image is enlarged using only one field of signals, the number of pixel signals used will be smaller than that of the first embodiment, and the image quality will be reduced by about half. In order to compensate for this shortage in the number of signals, a new field memory 6' is provided. Then, from the signal of the current field in the auxiliary memory 3 and the signal of the previous field in the field memory 6', signals of M×N pixels near the line position necessary for the enlarged image are extracted, and the signal is sent to the interpolation circuit 4' at the line position. Find it by interpolating the video signal level at . After constructing an expanded one-field video signal using the signal obtained by interpolation, the signal processing circuit 5 converts it into a television signal and outputs it as an expanded television signal.

On the other hand, the amount of movement of an image within a certain area of the image obtained by the image sensor (which does not need to be within the specified area) is expressed as a video signal delayed by one frame period using two field memories (51, 51). The motion amount detection circuit 7 compares and detects the signals of this field. Then, the position of the specified area specified by the enlargement position specifying circuit 8 is moved so that the relative movement of the specified area with respect to the position of the image within the part of the area where this motion detection is performed becomes small.

In this way, in the present imaging device as well, as in the first embodiment, the position of the area to be enlarged can be moved in accordance with the movement of the image within the area to be enlarged, and the movement of the image within the specified area can be reduced. Therefore, the position of the enlarged image can be almost fixed on the screen, and a good enlarged image with less image shaking can be obtained.

In addition, in Fig. 6, we have described the case in which image movement is detected from two signals separated by two field periods (one frame period), but it is also possible to detect image motion using signals of two consecutive fields. Needless to say, it's a good thing.

Furthermore, although we have only described the case of detecting image movement from captured images, it is also possible to move a designated area based on signals obtained from a camera vibration amount detection circuit installed separately within the camera. is clear.

Furthermore, signals may be read out from the image pickup device by reading out only the signals necessary for detecting image movement and configuring a television signal for an enlarged image.

Moreover, although only the case where a solid-state image sensor is used has been described above, it is clear that similar effects can be obtained when an image sensor such as an image pickup tube is used.

When using an image pickup tube, instead of using an interpolation circuit to obtain a television signal for an enlarged image or moving a specified area, the scanning position or area of the electron beam of the image pickup tube may be directly changed.

Furthermore, in the above embodiment, the case where the image is enlarged has been described, but it goes without saying that the same effect can be achieved even when the image is not enlarged or rather reduced. However, in this case, it is necessary to obtain the television signal in advance. It is necessary to use an image sensor having a number of pixels greater than the number of pixels required for this purpose.

〔Effect of the invention〕

As described above, according to the present invention, the position of the designated area to be imaged can be moved in accordance with the movement of the image within the designated area, and the movement of the image within the designated area can be reduced. Therefore, the position of the output image can be almost fixed on the screen, and a good image with little image shaking can be obtained. Furthermore, the conventional method of adjusting the zoom ratio using the mechanical mechanism of the lens allows the zoom ratio to be changed only at a relatively slow speed. On the other hand, in this method, the scaling operation is performed electrically, so
It will be possible to meet the harsh demands of photographers, such as wanting to enlarge and display a portion of a video all at once. For example, the unreconstructed image and the reconstructed image can be output to the viewfinder of a handy camera, etc., at the same time or in chronological order by switching with a switch, as shown in image 9 in Figure 1, or further reproduced. By displaying the designated area position and the motion detection position together in the image before composition, it is possible to facilitate photographing when zooming up or the like.

[Brief explanation of drawings]

1 is a block diagram of an imaging device according to an embodiment of the present invention; FIG. 2 is a plan view of an imaging device; FIGS. 3 and 5 are explanatory diagrams of pixel signal processing; and FIG. is an explanatory diagram of the relationship between an image and a scanning line. 1.1'... Solid image sensor, 2... Image storage circuit,
3...Auxiliary memory, 4,4'...Interpolation circuit, 5...
・Signal processing circuit, 6~6″...Field memory, 7
. . . Motion amount detection circuit, 8 . . . Enlargement position specification circuit, 1
0...Photodiode, 11...Vertical COD,
12...Horizontal CCO. No. 3 Closing traction force No. 3 Kasumi (α) Mouth/'''1゜mouth 12 0 Muro 14 0 ノ5 0 Tamekazu No. 1-74-IL-"k"'j42"74-1j'

Claims (1)

[Claims] 1. An optical lens and an imaging device (such as an imaging tube or solid-state imaging device) that converts the light passing through the optical lens into an electrical signal.
In an imaging device having an image sensor, reconstructing and outputting a video signal for image output from a video signal obtained in a specified area (hereinafter referred to as a designated area) on the light receiving surface of the image sensor, or further The position of the specified area is determined based on the magnitude of the motion vector signal and other signals obtained by motion detection of an image within a certain area of the image obtained by the image sensor (which does not need to be within the specified area). or further, the movement of the position of the specified area is performed such that the relative movement of the specified area with respect to the position of the image within the part of the area where the motion detection is performed is small. Imaging device. 2. In the imaging device according to claim 1, the imaging element includes:
A signal with the same number of lines as the number of horizontal lines of two consecutive fields of signals read during interlace operation,
It has a structure in which all fields can be read out independently, and the image pickup device is driven so that signals of the same number of lines as the horizontal lines of the two consecutive fields are read out all independently for each field. and a means for reconstructing the video signal for image output from the signals of M×N (M and N are integers) mutually adjacent pixels among the signals output from the pixel array constituting the image sensor. means to interpolate and obtain the signal level for the horizontal line position required for the image pickup device, or when further enlarging the image of the designated area by two times, the horizontal line signal independently read out from the image sensor is directly read out from the output. The average signal of the signals of two consecutive lines among the horizontal lines read independently from the image sensor is used as the signal of the horizontal line of the first field of the video signal for the image,
An imaging device comprising means for use as a horizontal line signal of a second field. 3. In the imaging device according to claim 1, when at least the image of the specified area is enlarged or reduced and outputted, at least on the screen of an image outputting device such as a finder of a television camera, which confirms the imaging position of the imaging device. In addition, means for outputting the image before enlargement or reduction and the enlarged image or reduced image simultaneously or in chronological order by switching with a switch or the like, or further detecting the position or movement of the specified area in the image before enlargement or reduction. An imaging device characterized by being provided with means for displaying a position. 4. In the imaging device according to claim 1, when the optical lens has a zoom function, a detection circuit for the zoom ratio of the optical lens is provided, and the zoom ratio of the zoom function is determined based on the detected zoom ratio; An imaging device characterized in that the magnification for enlarging or reducing the specified area is changed in conjunction with the magnification. 5. In the imaging device according to claim 1, among the array elements of two fields of signals continuously output from the imaging device, corresponding positions on the light receiving surface are adjacent to each other M×N (M
.