JPH0678198A - Image pickup device - Google Patents

Abstract

PURPOSE:To improve the operation convenience of an electronic zoom. CONSTITUTION:A photographed image obtained by an image pickup element 12 is temporarily stored in an image memory 18. An electronic zoom frame position selecting key 30 is a key for indicating the up/down and right/left movement of an electronic zoom frame in a photographed picture and a system control circuit 34 controls an image expanding circuit 20 in accordance with the state of the key 30. Namely the circuit 20 reads out an image at a position in the electronic zoom frame selected by the key 30 from the memory 18 and expands the read image to the extent of a prescribed field angle.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image pickup apparatus, and more particularly to an image pickup apparatus having an electronic zoom function.

[0002]

2. Description of the Related Art An image can be electronically enlarged by storing an image signal in an image memory having a storage capacity for at least one screen and reading out a part of image data of one screen. This is a function called electronic zoom. For example,
A part of the image shown in FIG. 2 can be enlarged as shown in FIG. 3 by performing some kind of coordinate transformation.

An image pickup apparatus having such an electronic zoom function is already known. In the conventional example, the image in the electronic zoom frame set at the center of the screen is enlarged and output according to the turn-on of the electronic zoom switch.

[0004]

As described above, in the conventional example, the subject to be electronically zoomed needs to be within the electronic zoom frame at the center of the screen, and the movement that is considered to be highly useful for the electronic zoom is performed. Not very effective for subjects with This is because the entire imaging device must be moved so that the subject always enters the electronic zoom frame in accordance with the movement of the subject. A camera shake easily occurs due to the movement of the entire imaging device.

An object of the present invention is to provide an image pickup apparatus which eliminates such inconvenience.

[0006]

An image pickup apparatus according to the present invention includes an electronic zoom frame position designating means for designating a position of an electronic zoom frame for designating a range of electronic zooming within a captured image, and the electronic zoom frame for the captured image. And an image enlarging means for electronically enlarging the image in the zoom frame to a predetermined angle of view.

[0007]

With the above means, it becomes possible to select the position for electronic zooming within the photographing screen. As a result, for example, a moving subject can be dealt with by moving the electronic zoom frame without moving the imaging device itself in many cases. It is less susceptible to external disturbances such as camera shake, making it easier to use the electronic zoom and improving usability.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a schematic block diagram of an embodiment of the present invention. 10 is a taking lens, 12 is a taking lens 1
An image sensor for converting an optical image by 0 into an electric signal, 14
Is a camera signal processing circuit that performs camera signal processing such as gamma correction and color adjustment on the output of the image pickup device 12 and outputs a luminance / color difference signal (or RGB format). 16 is an analog output of the camera signal processing circuit 14. It is an A / D converter for converting into a digital signal.

Reference numeral 18 denotes an image memory having a storage capacity for at least one screen, which temporarily stores the output image data of the A / D converter 16, and 20 denotes a predetermined range of the image stored in the image memory 18. It is an image enlarging circuit that performs coordinate conversion to electronically and enlarges electronically. When the designated range is the size of the screen, the image enlarging circuit 20 outputs the same size.

Reference numeral 22 denotes a D / A converter for converting the output data of the image enlarging circuit 20 into an analog signal, and 24 denotes an image signal output from the D / A converter 22 in a predetermined video format, for example, an NTSC format video signal. It is a video encoder to convert to. The output of the video encoder 24 is applied to an output terminal 26 and an electronic viewfinder (EVF) 28. A video recording device such as a video tape recorder or a video cassette recorder is connected to the output terminal 26.

Reference numeral 30 denotes an electronic zoom frame position selection key for selecting the position of the electronic zoom frame within the photographing screen, and is composed of, for example, a key switch for instructing movement up, down, left or right. Reference numeral 32 is an electronic zoom switch for instructing on / off of the electronic zoom. Reference numeral 34 is a system control circuit for controlling the whole, and specifically, controls the electronic zoom by the image memory 18 and the image enlarging circuit 20 according to the electronic zoom frame position selection key 30 and the electronic zoom switch 32.

In this embodiment, five areas A, B, C, D and E are set in the photographing screen, and the electronic zoom frame is moved to any of the five areas A, B, C, D and E. I made it possible. The electronic zoom frame position selection key 30 is used to select which region to move to. The areas A, B, C, D and E may have the same size or different sizes. Of course, the reason why the electronic zoom frame is moved to such a fixed position is because the control system becomes easy, and it goes without saying that the electronic zoom frame may be moved continuously. In this case, the key
The switch 30 may be an operation member such as a cross lever that is easier to operate.

Further, it goes without saying that the characteristics of the subject may be recognized or stored and the electronic zoom frame may be automatically moved so as to track a specific subject.

The operation of this embodiment will be described with reference to FIG. When the power is turned on, the image pickup device 12 converts the optical image from the taking lens 10 into an electric signal (S1, 2), and the camera signal processing circuit 14 processes the output of the image pickup device 12 by the camera signal (S3). The output of the camera signal processing circuit 14 is A / D
It is converted into a digital signal by the converter 16 (S4),
The image data is temporarily stored in the image memory 18 in screen units (S5).

When the electronic zoom switch 32 is on,
The system control circuit 34 uses the electronic zoom frame position selection key 3
From the state of 0, it is judged which one of the areas A, B, C, D or E is to be electronically zoomed, and the image enlarging circuit 20 stores the image data of the electronic zoom frame at the designated position in the image memory 1.
Read from 8 and expand to the full angle of view (S7,
8). When the electronic zoom switch 32 is off, the image enlarging circuit 20 reads the image data in the entire screen from the image memory 18 and outputs it as it is (S9).

The D / A converter 22 converts the digital output of the image enlarging circuit 20 into an analog signal (S10), and the encoder 24 converts the output of the D / A converter 22 into a video signal of a predetermined format (S11). . The output of the encoder 24 is applied to the electronic viewfinder 28, and the output terminal 26
Is output to the outside (S12). The output video signal of the encoder 24 is a signal representing an enlarged image of the image in the electronic zoom frame at the designated position when the electronic zoom is turned on.

For example, when the electronic zoom frame is moved to the area C, an enlarged image as shown in FIG. 6 can be obtained from the photographed image shown in FIG.

When the electronic zoom switch 32 is off, the output of the camera signal processing circuit 14 is directly supplied to the video encoder 24, and the electronic zoom switch 32 is supplied.
Is turned on, the output of the camera signal processing circuit 14
6 to 22 may be passed.

In the above embodiment, when the electronic zoom is in operation, the display screen of the electronic viewfinder 28,
Alternatively, the information outside the electronic zoom frame cannot be obtained from the output signal of the output terminal 26. Information outside the electronic zoom frame is used as a material for determining whether to turn off the electronic zoom.
Sometimes needed.

An embodiment satisfying such a demand will be described below. FIG. 7 shows a block diagram of the configuration. Reference numeral 40 is a taking lens, 42 is an image sensor, 44 is a camera signal processing circuit, 46 is an A / D converter for converting the analog output of the camera signal processing circuit 44 into a digital signal, and 48 is an image memory. These are the same as elements 10-18 in FIG.

Reference numeral 50 denotes an image enlarging circuit for coordinate-converting a designated range of the image stored in the image memory 18 into a predetermined size and electronically enlarging the image. Reference numeral 52 designates the image stored in the image memory 18 to a predetermined size. This is an image reduction circuit for reducing. Similarly to the image enlarging circuit 20, the image enlarging circuit 50 outputs the same size when the designated range is the size of the screen. An image combining circuit 54 combines (and selects) the outputs of the image enlarging circuit 50 and the image reducing circuit 52.

Reference numeral 56 is a D / A converter for converting the output data of the image synthesizing circuit 54 into an analog signal, and 58 is an image signal output from the D / A converter 56, which is a video signal of a predetermined video format, for example, NTSC format. It is a video encoder to convert to. The output of video encoder 58 is applied to output terminal 60 and electronic view finder (EVF) 62.

Reference numeral 64 is an electronic zoom frame position selection key similar to the electronic zoom frame position selection key 30, and 66 is an electronic zoom
Electronic zoom switch similar to switch 32, 68 is
This is a sub-screen display switch for designating whether or not to display the captured image on the sub-screen. Reference numeral 70 denotes a system control circuit for controlling the whole, and more specifically, an electronic zoom frame position selection key 64
The electronic zoom is controlled according to the electronic zoom switch 64, and the small screen display of the captured image is controlled according to the small screen display switch 68.

To explain the characteristic part of this embodiment, the image enlarging circuit 50, when the electronic zoom switch 66 is on, is the area designated by the electronic zoom frame position selection key 64 as in the embodiment of FIG. Electronically enlarge the image of.
The image reduction circuit 50 reduces the entire captured image stored in the image memory 48 to a predetermined size.

When the small screen display switch 68 is on, the image synthesizing circuit 54 synthesizes and outputs the reduced image output from the image reducing circuit 52 at a predetermined position of the enlarged image output from the image enlarging circuit 50. . Sub screen display switch 68
When is off, the image composition circuit 54 causes the image enlargement circuit 50 to
The output image of is output as it is.

When the electronic zoom switch 66 and the small screen display switch 68 are both turned on by the image enlarging circuit 50, the image reducing circuit 52 and the image synthesizing circuit 54, the output image of the image synthesizing circuit 54 is, for example, as shown in FIG. Like An image outside the electronic zoom range can be known from the small screen.

When it is desired that the video signal output from the output terminal 60 to the outside is only the video after the electronic zoom, the output of the image enlarging circuit 50 is sent by another video encoder to NTSC.
Convert the format etc. and output it and video encoder 58
It suffices that the output of 1 can be selectively supplied to the output terminal 60.

When a frame line corresponding to the set electronic zoom frame is displayed in the sub-screen, the degree of utilization of the electronic zoom is increased. For this purpose, the frame line data may be written in the image memory 48 at the electronic zoom frame position selected by the electronic zoom frame position selection key 64.

Although the position of the electronic zoom frame is freely changeable in the above embodiment, the size of the electronic zoom frame may be changeable by providing means for setting the size of the electronic zoom frame.

[0031]

As can be easily understood from the above description, according to the present invention, the electronic zoom frame can be moved, so that the electronic zoom frame can be moved according to the movement of the object instead of the image pickup device. As a result, camera shake of the image pickup apparatus is reduced. Therefore, the electronic zoom can be used more effectively.

[Brief description of drawings]

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

FIG. 2 is an example of a captured image.

FIG. 3 is an image example in which a central portion of the image in FIG. 2 is electronically enlarged.

FIG. 4 is an example of a moving destination of the electronic zoom frame in the present embodiment.

FIG. 5 is an operation flowchart of the present embodiment.

6 is an image after electronic zoom when the electronic zoom frame is moved to a region C in FIG.

FIG. 7 is a configuration block diagram of another embodiment of the present invention.

FIG. 8 is a composite image according to the present embodiment.

[Explanation of symbols]

10: Photographic lens 12: Image sensor 14: Camera signal processing circuit 16: A / D converter 18: Image memory 2
0: Image enlargement circuit 22: D / A converter 24: Video encoder 26: Output terminal 28: Electronic view finder (EVF) 30: Electronic zoom frame position selection key 32: Electronic zoom switch 34: System control circuit 40 : Photographing lens 42: Image sensor 44: Camera signal processing circuit 46: A / D converter 48: Image memory 50: Image enlarging circuit 52: Image reducing circuit 54: Image synthesizing circuit 56: D / A converter 58: Video Encoder 60: Output terminal 62: Electronic view finder (EVF) 64: Electronic zoom frame position selection key 6
6: Electronic zoom switch 68: Sub-screen display switch 70: System control circuit

Claims (4)

[Claims] 1. An electronic zoom frame position designating unit for designating a position of an electronic zoom frame for designating a range to be electronically zoomed in a captured image, and an image within the electronic zoom frame of the captured image is electronically set at a predetermined angle of view. And an image enlarging means for enlarging the image. 2. The image pickup apparatus according to claim 1, further comprising image reducing means for reducing the picked-up image and image synthesizing means for synthesizing the output of the image reducing means with the output of the image enlarging means. 3. An image pickup apparatus comprising an electronic zoom means, characterized in that an electronic zoom frame for designating a range to be electronically zoomed in a picked-up image is changeable. 4. The image pickup apparatus according to claim 3, further comprising image reducing means for reducing the picked-up image, and image synthesizing means for synthesizing the output of the image zooming means with the output of the electronic zooming means.