JP4119533B2 - Electronic camera and control method thereof - Google Patents

Description

[0001]
【Technical field】
The present invention relates to an electronic camera that images a subject and outputs image data representing the subject image, and a control method thereof.
[0002]
BACKGROUND OF THE INVENTION
Some so-called silver halide cameras that record a subject image on a photographic film have an imaging lens held at the tip of the bellows. In such a camera, the user moves the bellows by hand and shifts the optical axis on the image plane of the photographic film and the optical axis of the imaging lens (tilting correction) to focus multiple subjects at different distances. Can do.
[0003]
Some electronic cameras that use a solid-state electronic image sensor to image a subject are tilted while tilting the image sensor (Japanese Patent Application Laid-Open No. 9-331476). I can't.
[0004]
In addition, when tilt correction is performed in the electronic camera, it may be difficult to confirm which part is in focus within the imaging range.
[0005]
In addition, there is a demand for obtaining the same effect as a mechanical tilt (so-called electronic tilt correction) in consideration of the characteristics of an electronic camera that digital image data representing a subject image can be obtained. Yes.
[0006]
DISCLOSURE OF THE INVENTION
An object of the present invention is to provide an electronic camera capable of correcting tilting in an arbitrary direction.
[0007]
Another object of the present invention is to make it possible to confirm a focusing range within an imaging range when tilt correction is performed.
[0008]
Another object of the present invention is to enable so-called electronic tilt correction.
[0009]
An electronic camera according to a first aspect of the present invention is a solid-state electronic image pickup device that outputs image data representing a subject image by forming a subject image on the light-receiving surface, and the solid-state electronic image pickup device so that the light-receiving surface can be tilted. A solid-state electronic image sensor support mechanism for supporting the tilt angle, a tilt detection means for detecting a tilt angle and a tilt direction, and a control mechanism for the solid-state electronic image sensor support mechanism based on the tilt angle and the tilt direction detected by the tilt detection means. And a tilt control means.
[0010]
The first invention also provides a method suitable for the electronic camera. In other words, the solid-state electronic image pickup device is supported so that the light-receiving surface of the solid-state electronic image pickup device that outputs image data representing the subject image by forming a subject image on the light-receiving surface is tiltable. The angle and the tilt direction are detected, respectively, and the support of the solid-state electronic image sensor is controlled based on the detected tilt angle and tilt direction.
[0011]
According to the first invention, the solid-state electronic image pickup device is supported so that the light receiving surface of the solid-state electronic image pickup device can be tilted. When the tilt angle and the tilt direction are detected by the tilt detection means, the support of the solid-state electronic image sensor is controlled based on the detected tilt angle and tilt direction (for example, the same angle as the tilt angle or a larger angle or The support of the solid-state electronic image sensor is controlled so that it tilts in the same direction as the tilt direction by a small angle).
[0012]
The light receiving surface of the solid-state electronic image pickup device is arranged to have an arbitrary inclination.
[0013]
When the electronic camera further includes a bellows unit including an imaging lens that forms an image of a subject on the light receiving surface of the solid-state electronic imaging device, the user operates the tilt unit. The tilt angle and tilt direction are detected based on this operation. Further, input means for inputting the tilt angle and the tilt direction is provided, and the solid-state electronic image sensor is supported so that the light receiving surface of the solid-state electronic image sensor has an arbitrary inclination based on the input tilt angle and tilt direction. It may be controlled.
[0014]
In an electronic camera further comprising a strobe light emitting device and a strobe capacitor for charging a driving voltage for causing the strobe light emitting device to emit light, the drive voltage of the tilt control means is supplied from the strobe capacitor. May be.
[0015]
It is not necessary to newly provide a driving power source for the tilt control means.
[0016]
Since the electronic camera body is required to be downsized, the size of the monitor display device provided in the electronic camera is naturally limited. For this reason, the resolution of the monitor display device is often low. Even if the tilt correction is performed and the subject is imaged, it is difficult to check whether the subject is in focus.
[0017]
For this reason, a display device for displaying a subject image represented by image data output from the solid-state electronic image sensor, a tilt confirmation command input means for inputting a tilt confirmation command, and a tilt input from the tilt confirmation command input means. In response to the confirmation command, the display device may further include display control means for controlling the display device so that a part of the subject image displayed on the display device is enlarged and displayed.
[0018]
Since a part of the subject image can be enlarged, it is easy to check whether the enlarged part is in focus.
[0019]
An electronic camera according to a second aspect of the invention is an image pickup means for picking up the same subject at a plurality of different focal lengths and outputting image data representing a plurality of frames of the subject image, and a plurality of images represented by the image data output from the image pickup means. Partial region image data extraction that divides each subject image of a frame into each of the plurality of partial regions and extracts partial region image data representing a partial region that is in focus among the partial regions in the subject image of each frame And image synthesizing means for generating and outputting synthesized image data representing a subject image by combining the partial areas represented by the partial area image data extracted by the partial area image data extracting means. It is characterized by.
[0020]
The second invention also provides a method suitable for the electronic camera. That is, the same subject is imaged multiple times at different focal lengths to obtain image data representing a subject image of a plurality of frames, and each of the subject images of the plurality of frames represented by the obtained image data is each part of the number of the plurality of frames. Dividing into regions, extracting partial region image data representing the partial region in focus among the partial regions in the subject image of each frame, combining the partial regions represented by the extracted partial region image data, This generates and outputs composite image data representing a single subject image.
[0021]
According to the second invention, a composite image of one frame is obtained by using the plurality of partial areas in focus. In the obtained composite image of one frame, all the areas are in focus. Electronic tilt can be realized without mechanical tilt correction.
[0022]
According to a third aspect of the present invention, there is provided an electronic camera that detects a tilt angle and a tilt direction, an image capturing unit that captures an image of a subject and outputs image data representing a subject image, and a tilt angle detected by the tilt detection unit. Edge enhancement amount calculation means for calculating an edge enhancement amount for each region of the subject image based on the tilt direction, and an image output from the imaging means based on the edge enhancement amount calculated by the edge enhancement amount calculation means The image processing apparatus is characterized by comprising edge enhancement means for edge enhancement of a subject image represented by data.
[0023]
The third invention also provides a method suitable for the electronic camera. That is, the tilt angle and tilt direction are detected, the subject is imaged, image data representing the subject image is obtained, and the edge enhancement amount for each region of the subject image is calculated based on the detected tilt angle and tilt direction. Based on the calculated edge enhancement amount, the subject image represented by the image data obtained by imaging is edge-enhanced.
[0024]
According to the third invention, the tilt angle and the tilt direction are detected by the tilt detection means. An edge enhancement amount for each region of the subject image is calculated based on the detected tilt angle and tilt direction. Image data representing the subject image is edge-enhanced based on the calculated edge enhancement amount.
[0025]
Since the edge is emphasized, even if the subject image is blurred without being focused, it appears as a focused subject image.
[0026]
[Explanation of Examples]
FIG. 1 is a block diagram showing the electrical configuration of the electronic camera according to this embodiment. The overall operation of the electronic camera is controlled by the control CPU 10.
[0027]
When imaging multiple subjects at different distances, it is difficult to focus on all subjects. Correction is performed to obtain an image in which all subjects are in focus. The electronic camera is provided with a retractable bellows 3 for correcting tilt.
[0028]
An imaging lens 1 is held on the distal end surface 2 of the bellows 3. The user sets the tilt angle and the tilt direction by moving the rear end surface 4 of the bellows 3 up and down, left and right. The tilt correction is performed based on the set tilt angle and direction. The tilt angle and the tilt direction may be set by moving the front end surface 2 of the bellows 3 up and down and left and right.
[0029]
The moving angle and the moving direction (tilting angle and tilting direction) of the rear end surface 4 of the bellows 3 are detected by the displacement sensor 5. Data representing the tilt angle and tilt direction detected by the displacement sensor 5 is input to the control CPU 10.
[0030]
The displacement sensor 5 can be a sensor that detects the tilt angle and tilt direction of a joystick. The tilt angle and tilt direction of the rear end surface 4 of the bellows 3 are detected in the same manner as when detecting the tilt angle and tilt direction of the joystick.
[0031]
A subject image is formed on the light receiving surface of the CCD 6 by the imaging lens 1. A video signal representing the subject image is output from the CCD 6 and input to the imaging circuit 8. The video signal is converted into digital image data by the imaging circuit 8 and output. The electronic camera includes a first image memory 11A to a fourth image memory 11D, each of which can store image data representing an image of one frame. Therefore, the electronic camera can temporarily store image data representing four frames.
[0032]
Image data output from the imaging circuit 8 is temporarily stored in the first image memory 11A. However, other image memories 11B to 11D may be stored. The image data stored in the first image memory 11A is read from the first image memory 11A and input to the image reproduction device 13. The image data is subjected to reproduction processing in the image reproduction device 13 and input to the display device 20. The captured subject image is displayed on the display screen of the display device 20.
[0033]
The image data temporarily stored in the first image memory 11A is also input to the external storage device 12. Image data representing the subject image is stored in a storage medium (memory card, floppy disk, etc.) by the external storage device 12.
[0034]
Electronic cameras are capable of strobe imaging. A strobe light emitting device 15 is provided for strobe imaging. The strobe control circuit 14 is controlled by the control CPU 10. The electric charge charged in the strobe capacitor 16 is discharged by the strobe control circuit 14, and the strobe light emitting device 15 emits light. The electric charge accumulated in the strobe capacitor 16 is also used to drive the piezoelectric element 7.
[0035]
The four corners of the CCD 6 are supported by the piezoelectric element 7 so as to be tiltable. The piezoelectric element 7 is controlled by a piezoelectric element control circuit 9.
[0036]
When the rear end face 4 of the bellows 3 is moved by the user, the tilt angle and the tilt direction are detected by the displacement sensor 5. Data representing the detected tilt angle and tilt direction is input from the displacement sensor 5 to the control CPU 10. The piezoelectric element control circuit 9 is controlled by the control CPU 10, and the piezoelectric elements 7 supporting the four corners of the CCD 6 are controlled by the piezoelectric element control circuit 9. The CCD 6 is tilted by the piezoelectric element 7 and tilt correction is executed.
[0037]
The degree of inclination of the CCD 6 determined based on the tilt angle and tilt direction detected by the displacement sensor 5 can be freely set by the user. For example, it may be the same as the case where the tilt correction is performed by moving the bellows in a 6 × 7 film camera, or the same as the case where the tilt correction is performed by moving the bellows in a 6 × 9 film camera.
[0038]
In the electronic camera described above, the user may set the tilt angle and the tilt direction by moving the rear end 4 of the bellows 3, and the user may input the tilt angle and the tilt direction.
[0039]
As the pixel pitch of the CCD 6 becomes finer, micron-order control is required for tilt control of the CCD 6. Since the pixel pitch is several μm, the image surface depth at the CCD 6 is about 2 × (several μm) = 10 μm if the open aperture is about F2. By using the piezoelectric element 7, high-precision control is possible.
[0040]
The piezoelectric element 7 requires a voltage of about 100V to 200V for control. As described above, since the electric charge for strobe light emission is accumulated in the capacitor 16, the electric charge accumulated in the capacitor 16 can be used as a drive voltage for the piezoelectric element 7. This eliminates the need for a dedicated power source for driving the piezoelectric element 7.
[0041]
2A and 2B show an example of the display screen of the display device 20. FIG.
[0042]
Referring to FIG. 2A, the display screen of display device 20 includes image display area 21, tilt command area 25 and tilt confirmation mode setting area 26.
[0043]
In the image display area 21, a subject image obtained by imaging is displayed. In the example shown in FIG. 2A, there are first to fourth subjects at different distances. The fourth subject is imaged from these first subjects, and the first subject image OB1 to the fourth subject are captured. Subject image OB4 is displayed. As the first subject changes to the fourth subject, the distance gradually decreases. The fourth subject image OB4 is in focus and is blurred as it becomes the first subject image OB1.
[0044]
In the tilt command area 25, four arrows are displayed in the vertical and horizontal directions. When the user touches an arrow representing a desired direction from among these four arrows, the tilt direction is input to the electronic camera as a command. Further, the time during which the user touches the arrow in the tilt command area 25 is measured by a counter (not shown) in the control CPU 10. The tilt angle is determined based on the time the user is touching the arrow. If the user touches the arrow for a long time, the tilt angle increases.
[0045]
Data representing the tilt angle and tilt direction input from the tilt command area 25 is input to the control CPU 10, and the piezoelectric element control circuit 9 is controlled by the control CPU 10. The piezoelectric element 7 is driven by the piezoelectric element control circuit 9, and the CCD 6 is tilted.
[0046]
When the tilt confirmation mode setting area 26 on the display screen of the display device 20 is touched by the user, the tilt confirmation mode is set.
[0047]
In the tilt confirmation mode, the image display area 21 is divided into five as shown in FIG. The image display area 21 includes a first image enlargement display area 22A, a second image enlargement display area 22B, a third image enlargement display area 22C, a fourth image enlargement display area 22D, and a fifth image enlargement display area 22E. It is included.
[0048]
As shown in FIG. 21A, the first image enlargement display area 22A has an area of the same size as that obtained when the subject image displayed in the image display area 21 is divided into 16 parts and is divided into 16 parts at the center. When formed, the first image division area 21A including the upper left corner of the image display area 21 is enlarged to an area ratio of 4 times.
[0049]
Similarly, the second image enlargement display area 22B is obtained by enlarging the second image division area 21B including the lower left corner portion of the image display area 21 by an area ratio of 4 times. 22C is an enlargement of the third image division area 21C including the upper right corner of the image display area 21 by an area ratio of 4 times. The fourth image enlargement display area 22D is the lower right corner of the image display area 21. The fourth image division region 21D including the portion is enlarged by an area ratio of four, and the fifth image enlargement display region 22E is the fifth image division region 21E including the center portion of the image display region 21. Is expanded to an area ratio of about 4 times.
[0050]
Due to the size limitation of the electronic camera, the display screen of the display device provided in the electronic camera is generally small. Therefore, the resolution of the display device is low, and it is difficult to confirm whether the subject image is in focus. In the electronic camera according to this embodiment, when the tilt check mode is set, a part of the display area of the display screen is enlarged and displayed, so that it is relatively easy to check whether the subject image is in focus. .
[0051]
In FIG. 2B, the display is divided into five parts. However, the display is not limited to the five parts display, but may be displayed according to another division method. Further, a part of the image display area 21 may be enlarged and displayed on the entire surface of the image display area 21 without splitting the image display area 21.
[0052]
3 to 5 show another embodiment. 3 is a block diagram showing the electrical configuration of the electronic camera, FIGS. 4A, 4B, 4C, and 4D show examples of subject images, and FIG. 5 shows the electronic camera shown in FIG. Shows an example of a composite image obtained by.
[0053]
In FIG. 3, the same components as those shown in FIG.
[0054]
In the electronic camera shown in FIG. 3, the bellows 3 is not provided. A lens barrel 30 including an imaging lens unit (not shown) is provided in front of the CCD 6. A motor 18 for driving the imaging lens unit is provided. The motor 18 is driven by a motor control circuit 17.
[0055]
The imaging lens unit is driven by the motor 18 to focus at a plurality of different focal lengths, and the same subject image is captured at each focal length.
[0056]
In this embodiment, the first imaging, the second imaging, the third imaging, and the fourth imaging are performed at the focal length A, the focal length B, the focal length C, and the focal length D, respectively. The image data representing the subject image is obtained at the focal length (see FIGS. 4A, 4B, 4C, and 4D). Image data obtained by the first imaging is stored in the first image memory 11A, and image data obtained by the second imaging is stored in the second image memory 11B. Image data obtained by imaging is stored in the third image memory 11, and image data obtained by the fourth imaging is stored in the fourth image memory 11D.
[0057]
Referring to FIG. 4A, the region A is in focus in the image at the focal length A. Referring to FIG. 4B, the region B is in focus in the image at the focal length B. Referring to FIG. 4C, the region C is in focus in the image at the focal length C. Referring to FIG. 4D, the region D is in focus in the image at the focal length D.
[0058]
Image data representing four frames of images temporarily stored in the image memories 11A to 11D is read from the image memories 11A to 11D and input to the control CPU 10. In the control CPU 10, image data representing the image portion of the region A is extracted from the image at the focal length A shown in FIG. 4A, and the region B of the image at the focal length B shown in FIG. Image data representing the image portion is extracted, and image data representing the image portion in the region C is extracted from the image at the focal length C shown in FIG. 4C, and the focal length D shown in FIG. Image data representing the image portion of region D is extracted from the image.
[0059]
Using the extracted partial image data representing the image portion of the region A, partial image data representing the image portion of the region B, partial image data representing the image portion of the region C, and partial image data representing the image portion of the region D, As shown in FIG. 5, they are combined so as to represent an image of one frame. The obtained composite image is all in focus in each region. Even if the subject is at a different distance, a subject image in which all subjects are in focus can be obtained.
[0060]
6 and 7 show still another embodiment. FIG. 6 is a block diagram showing the electrical configuration of the electronic camera, and FIG. 7 shows an example of a subject image. Also in FIG. 6, the same components as those shown in FIG. 1 and FIG.
[0061]
A subject is imaged by the CCD 6, and image data representing the subject image is temporarily stored in the image memory 11.
[0062]
The rear end surface 4 of the bellows 3 is moved by the user, the tilt angle and the tilt direction are detected by the displacement sensor 5, and data representing the tilt angle and the tilt direction is input to the control CPU 10.
[0063]
The image data temporarily stored in the image memory 11 is read from the image memory 11 and input to the control CPU 10.
[0064]
The control CPU 10 can perform image edge enhancement processing. The control CPU 10 performs edge enhancement processing on the subject image represented by the input image data according to the tilt angle and tilt direction. By this edge enhancement processing, it is possible to make the subject image that is out of focus and out of focus because it is at different distances appear to be in focus.
[0065]
FIG. 2A shows a subject image obtained when a plurality of subjects at different distances are captured without performing edge enhancement processing as described above. In this way, the fourth subject image OB4 is in focus, but the first subject image OB1 is out of focus. By subjecting image data representing such a subject image to edge enhancement processing for a subject that is farther away, a subject image that appears to be in focus as shown in FIG. 7 can be obtained. .
[0066]
In the electronic camera shown in FIG. 6, the tilt angle and the tilt direction are set by the user moving the rear end surface 4 of the bellows 3, but as shown in FIGS. 2A and 2B, the tilt command is set. It is also possible to input the tilt angle and tilt direction from the area.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an electrical configuration of an electronic camera.
FIGS. 2A and 2B show an example of a display screen of a display device.
FIG. 3 is a block diagram showing an electrical configuration of the electronic camera.
FIGS. 4A to 4D show examples of subject images. FIGS.
FIG. 5 shows an example of a composite image.
FIG. 6 is a block diagram showing an electrical configuration of the electronic camera.
FIG. 7 shows an example of a subject image.
[Explanation of symbols]
1 imaging lens 3 bellows 4 rear end face 5 displacement sensor 6 CCD
7 Piezoelectric element 8 Imaging circuit 9 Piezoelectric element control circuit
10 Control CPU
11, 11A, 11B, 11C, 11D Image memory
13 Image playback device
20 Display device

Claims (4)

A solid-state electronic image sensor that outputs image data representing a subject image by forming the subject image on a light receiving surface;
A solid-state electronic image sensor support mechanism for supporting the solid-state electronic image sensor so that the light-receiving surface is tiltable;
Tilt detection means for detecting the tilt angle and tilt direction ,
A tilt control means for controlling the solid-state electronic image sensor support mechanism based on a tilt angle and a tilt direction detected by the tilt detection means, and
A bellows unit including an imaging lens that forms an image of a subject on the light receiving surface of the solid-state electronic imaging device;
The tilt detection means detects the tilt angle and tilt amount of the bellows unit.
Electronic camera. A strobe light emitting device, and a strobe capacitor for charging a driving voltage for causing the strobe light emitting device to emit light,
2. The electronic camera according to claim 1, wherein the drive voltage of the tilt control means is supplied from the strobe capacitor. A display device for displaying a subject image represented by image data output from the solid-state electronic image sensor;
A tilt confirmation command input means for inputting a tilt confirmation command, and a part of the subject image displayed on the display device is enlarged and displayed in response to the tilt confirmation command input from the tilt confirmation command input means. Display control means for controlling the display device,
The electronic camera according to claim 1, further comprising: The solid-state electronic imaging device is supported so that the light-receiving surface of the solid-state electronic imaging device that outputs image data representing the subject image by forming a subject image on the light-receiving surface is tiltable,
Detect the tilt angle and tilt direction,
In a control method of an electronic camera for controlling support of the solid-state electronic image pickup device based on a detected tilt angle and tilt direction ,
The electronic camera includes a bellows unit including an imaging lens that forms an image of a subject on the light receiving surface of the fixed electronic imaging element.
The detection of the tilt angle and the tilt direction is to detect the tilt angle and tilt amount of the bellows unit.
Control method of electronic camera.

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