JP2007300210A - Photographing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photographing apparatus capable of preventing the erroneous operation of a photographer in mistake in the case of acquiring a reference image for azimuth correction. <P>SOLUTION: In a digital camera that is provided with: an observation optical system for observing a photographing range; an imaging element for outputting an object image imaged by a photographing optical system as electric image data; and a display device 12 for displaying a photographed image photographed by the imaging element, uses the visual field of the observation optical system to determine horizontality or verticality of an object, calculates an azimuth correction amount between the imaging element and the observation optical system from a photographed reference image, and uses the calculated azimuth correction amount to correct the azimuth of the photographed image, the display device 12 does not display the image formed by the imaging element and output by the observation optical system in the case of acquiring the reference image. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a photographing apparatus provided with an observation optical system.

There are two types of cameras, which are photographing devices, one using a silver salt film and the other digital cameras capable of recording and storing captured images and videos electronically and magnetically without using a silver salt film.
By the way, as a method of determining the shooting range when taking a digital image with a digital camera, the output of the image sensor is displayed on a liquid crystal monitor on the back of the photographing device and directly observed, or a small liquid crystal monitor is displayed with a lens. A method of using a display device such as a so-called EVF (Electric View Finder) system for magnifying observation is common.
However, the former has the drawbacks that display is difficult to see in bright outdoors and camera shake tends to occur because the camera is held away from the face. Further, the latter has the disadvantages that the apparatus becomes large and portability deteriorates and the cost increases.

Further, a common disadvantage of both is that the power consumption is large, so the battery is consumed quickly and the number of shots is reduced. For this reason, as in the case of taking a picture with a silver halide film camera, there is a considerable demand for photographers who want to take pictures using a so-called optical observation optical system such as a real image type or an inverse Galileo type. .
In Patent Documents 1 to 3, in an observation optical system that uses an objective lens in common with a photographing optical system, the posture of the photographing lens of the camera body around the optical axis is displayed in the observation optical system field of view. The invention is disclosed. However, Patent Documents 1 and 2 only present information to a photographer before photographing, and do not correct image data of a photographing result. Patent Document 3 warns the photographer of the tilt of the camera body by vibration, and does not correct the photographing result.

Patent Document 4 discloses a technique for processing image data of a photographing result in accordance with the observation range of the observation optical system by reflecting a change in the aspect ratio of the visual field of the observation optical system in the photographed image. Patent Document 5 discloses a technique for changing the aspect ratio and trimming within the photographing range while viewing the image data of the photographing result. These Patent Documents 4 and 5 are techniques related to the change of the field of view and imaging data of the observation optical system, but do not mention the azimuth shift between the observation optical system and the image sensor.
Further, Patent Document 6 discloses a technique for matching the photographing range with the visual field range of the observation optical system, but so-called parallax correction that changes the visual field range of the observation optical system according to distance information to the subject. No mention is made of the azimuth shift between the observation optical system and the image sensor.
Patent Document 7 discloses a technique for correcting the azimuth shift between the observation optical system and the image sensor, but is a technique for adjusting a field frame in the observation optical system at the time of manufacturing a photographing apparatus, and an image after photographing. It did not correct the data.
JP-A-11-352570 JP 04-125532 A Japanese Patent Laid-Open No. 11-338037 JP 2004-163934 A JP 2004-166271 A JP 2003-222937 A JP 2003-098573 A

However, in the case of the optical observation optical system built in the current miniaturized photographing apparatus, the azimuth of the optical observation optical system with respect to the image pickup device is guaranteed because of the tolerance of parts and the variation in assembly. hard. Further, even when adjusting the position of the field frame in the optical observation optical system and adjusting the azimuth, it is difficult and impossible for the photographer to make adjustments to such an extent that the azimuth is not felt.
Needless to say, when using a single optical observation optical system that is attached using an accessory attachment device typified by the accessory attachment seat defined in JIS B7101, the built-in optical observation optical system is used. The possibility that the azimuth shift occurs more than the case becomes larger.
For this reason, if photographing is performed using an optical observation optical system in which the azimuth is shifted without using a display device such as a liquid crystal monitor or EVF, the azimuth of all captured images is shifted.

Therefore, the azimuth correction amount between the image sensor and the optical observation optical system is calculated from a reference image obtained by determining the horizontal or vertical direction of the subject using the field of view of the optical observation optical system, and the calculated azimuth correction amount is calculated. It is conceivable to correct the azimuth of the photographed image using this.
However, when acquiring the reference image as described above, if the photographer mistakenly acquires the reference image using the captured image displayed on the display device instead of the field of view of the optical observation optical system, The azimuth shift will not be reflected.
The present invention has been made in view of the above points, and an object of the present invention is to provide an imaging apparatus capable of preventing an erroneous operation when acquiring a reference image for performing azimuth correction.

  In order to achieve the above object, an imaging device of the present invention includes at least an observation optical system for observing an imaging range, and an imaging element that outputs a subject image formed by the imaging optical system as electrical image data. Display means for displaying a photographed image photographed by the image sensor, and determining the horizontal or vertical of the subject using the field of view of the observation optical system, and the image sensor and the observation optical system from a reference image photographed. An azimuth correction amount between the image pickup device and the azimuth of the captured image is corrected using the calculated azimuth correction amount, and when the reference image is acquired, Control means for controlling not to display the image formed and output on the display means is provided.

In the photographing apparatus of the present invention, the control unit performs display control for displaying the reference image acquisition procedure on the display unit when the reference image is acquired.
Further, in the photographing apparatus of the present invention, when the control unit displays the photographed image on the display unit when acquiring the reference image, any one or more of brightness, saturation, and hue is normally displayed. Control is performed so that the display state is different from the state.
In the imaging apparatus of the present invention, when the control unit acquires the reference image, the control unit superimposes the acquisition procedure of the reference image on a captured image having a display state different from a normal display state on the display unit. It is characterized by displaying.
The imaging apparatus of the present invention is characterized in that the observation optical system is a built-in built-in observation optical system or an externally attachable single observation optical system.
Further, the photographing apparatus of the present invention includes a detecting unit that detects attachment of the single observation optical system, and is configured to be able to acquire a reference image of the single observation optical system when the single observation optical system is detected. It is characterized by that.

  According to the present invention, when the reference image is acquired, the field of view of the observation optical system is originally used by controlling so that the image formed and output on the image sensor by the imaging optical system is not displayed on the display unit. Thus, it is possible to prevent an erroneous operation such that the photographer mistakenly captures the reference image by using the display means at the place where the reference image is to be obtained.

Hereinafter, embodiments of the photographing apparatus of the present invention will be described.
1A and 1B are views showing an external appearance of a digital camera that is an embodiment of a photographing apparatus of the present invention. FIG. 1A is a front view and FIG. 1B is a rear view.
As shown in FIG. 1A, on the front surface of the digital camera 1, a photographing lens 2 constituting a photographing optical system, an objective window 3 of a built-in observation optical system (not shown), a flash window 4, and the like are provided. ing. Further, an accessory shoe 5 for attaching an external observation optical system and a shutter button 6 are provided on the upper surface of the digital camera 1.
Further, as shown in FIG. 1B, on the back of the digital camera 1, an eyepiece window 11 for observing a photographing range through an observation optical system incorporated by a photographer, a display device 12 such as an LCD, and the like. An operation button 13 is provided.

FIG. 2 is a diagram showing the azimuth relationship between the imaging device and the observation optical system of the digital camera of this embodiment, and FIG. 2A is a diagram showing the azimuth relationship between the imaging device and the built-in observation optical system. (B) is a diagram showing the azimuth relationship between the image sensor and the external observation optical system. FIG. 3 is a diagram showing an example of the field of view of the observation optical system and a photographed image, FIG. 3A is a diagram showing a field frame image of the observation optical system, and FIG. 3B is a diagram showing a photographed image. is there.
In a mass-produced product, when the azimuth of the built-in observation optical system is shifted from the azimuth of the image sensor 20 as shown in FIG. 2A, or as shown in FIG. In many cases, the azimuth of the observation optical system and the azimuth of the image sensor 20 are shifted.
In such a case, when an image is taken using the observation optical system, the photographed image corresponding to the field frame of the observation optical system as shown in FIG. A tilted shooting screen as shown is recorded. That is, the azimuth of the shooting screen and the azimuth of the subject as shown in FIG. 3B do not match (horizontal) even though it is desired to obtain an image in which the azimuth of the shooting screen matches the azimuth of the subject (leveled). The image will be recorded.

Therefore, the digital camera 1 is configured to correct the azimuth shift between the image sensor 20 and the observation optical yarn. When correcting the azimuth misalignment between the image pickup device 20 and the observation optical yarn, first, as shown in FIG. 4A, the horizontal and vertical references such as the field frame of the observation optical system or the AF target mark 22 are used. A reference image as shown in FIG. 4B is obtained by framing and taking a picture by combining a possible index and an azimuth of a subject whose horizontal and vertical components are clear. Next, by subjecting the obtained reference image to image processing, the tilt amounts θ ₁ and θ ₂ of the subject with respect to the field frame of the observation optical system are calculated as shown in FIG. In FIG. 4C, the angle formed between the extracted straight lines A, B, and C and the outer four sides of the image is nothing but the amount of azimuth shift between the observation optical system and the image sensor.

As a specific flow of the calculation method, first, image processing such as edge enhancement and black and white binarization is performed. Next, feature points / shapes such as straight lines and rectangles are extracted from the processed image. Thereafter, the inclination of the image is calculated from the coordinates of the feature points and the inclination of the shape.
The image processing and feature point extraction methods mentioned here are described in Japanese Patent Application Laid-Open No. 2005-278160, Japanese Patent Application Laid-Open No. 2005-122326, Japanese Patent Application Laid-Open No. 2005-122323, etc. Various techniques, such as a method for extracting a signal, are disclosed.
In the reference image, it is desirable that the subject plane and the imaging element plane are opposed and parallel to each other. However, when both have an angle, different angles θ ₄ and θ are extracted from the straight lines E and D extracted as shown in FIG. _Since it has ₃ , the azimuth deviation amount θ ₅ can be obtained by calculating and using a straight line F that bisects the angle formed by these straight lines.

FIG. 4E shows an example in which a rectangular shape is extracted by image processing using the image shown in FIG. 3B as a reference image. In this case as well, the azimuth deviation amount θ can be obtained similarly thereafter.
When the amount of azimuth displacement between the image sensor and the subject can be calculated, an image in which the azimuth is displaced can be corrected by reversely correcting the amount of azimuth displacement by the image processing means. Regarding the correction processing in the image processing means, there are many known examples such as Japanese Patent No. 2829006 and Japanese Patent No. 3303246, as well as Japanese Patent Laid-Open No. 08-161424, and in one example, it is easily possible by using coordinate transformation. is there.

FIG. 5 is a block diagram showing the configuration of the digital camera 1.
The digital camera 1 shown in FIG. 5 includes an imaging system block 30 and an azimuth processing block 40.
The photographing system block 30 includes a photographing optical system 31, an observation optical system 32 for observing a photographing range, and an imaging element 20 that outputs a subject image formed by the photographing optical system 31 as electrical image data. Composed.
The azimuth processing block 40 is an image recording unit 41 that records the image data output from the image sensor 20, and the image sensor 20 and the observation from the reference image that is taken by determining the horizontal or vertical of the subject using the field of view of the observation optical system. An azimuth information calculating unit 42 that calculates an azimuth correction amount with the optical system 32 is provided. Further, the azimuth information storage means 43 that stores the azimuth correction amount calculated by the azimuth information calculation means 42 as azimuth information, and the azimuth correction amount obtained from the azimuth information calculation means 42 or the azimuth information storage means 43 is used to capture a captured image. Image processing means 44 for correcting azimuth. Furthermore, a control unit 45 that performs selection control as to whether or not to perform azimuth correction processing by the image processing unit 44, recording control for recording the image data corrected by the image processing unit 44 in the image recording unit 41, and photographing. The apparatus includes a focal length information of the optical system 31 and auxiliary information input means 46 for inputting auxiliary data which is individual information of the observation optical system 32. Note that the azimuth information storage means 43 is preferably constituted by, for example, a nonvolatile semiconductor memory.

In the azimuth processing block 40 of the digital camera 1 configured as described above, the azimuth information calculation means 42 that has received the output of the reference image from the image sensor 20 calculates the azimuth correction amount of the image sensor 20 and the observation optical system 32 by the above-described method. The azimuth information is calculated and stored in the azimuth information storage means 43. At that time, the azimuth information storage means 43 can also store the auxiliary information in association with the auxiliary information. The azimuth information storage means 43 can store a plurality of azimuth information.
The image processing unit 44 corrects the image that has received the azimuth information from the azimuth information storage unit 43 and outputs the corrected image to the image recording unit 41. The image processing means 44 may only add azimuth information without correcting the image.
The control unit 45 performs control for recording the image data subjected to image processing by the image processing unit 44 in the image recording unit 41, recording control for recording the uncorrected image in the image recording unit 41, and the like. FIG. 6 is a diagram showing an example of information stored in the azimuth information storage means.

FIG. 7 is a flowchart showing a processing flow when the azimuth correction amount is calculated in the digital camera 1. Note that the azimuth correction amount calculation process described below is realized by the control unit 45 executing the process.
When a required operation for acquiring the azimuth correction amount is performed, the control means 45 determines whether or not the average mode is selected (ON) (S1). The average mode is a mode for obtaining a correction amount from an average value when a reference image is taken a plurality of times. When the correction amount is obtained from one reference image, the average mode is not selected (OFF).
If it is determined that the average mode is ON, processing for selecting and inputting the number of shots (number of shots) n times is performed (S2). Next, after setting the variable i to “1” (S3), it is determined whether or not the variable i is smaller than the value of n (S4). Photographing is performed (S5), and output data of the photographed reference image is once recorded in the image recording means 41 (S6), and then the azimuth correction amount is calculated by the azimuth information calculating means 42 (S7). Then, after adding “1” to the variable i (S8), the process returns to step S4, and the processes of steps S5 to S7 are repeated until the variable i reaches the set number of times of photographing n. When a positive result is obtained in step S4, that is, when i ≧ n is reached, the process proceeds to step S9 to calculate the average value of the azimuth correction amount.

On the other hand, if it is determined in step S1 that the average mode is OFF (N in S1), a reference image is taken (S10), and output data of the taken reference image is once recorded in the image recording means 41 (S11). ), An azimuth correction amount is calculated (S12).
In step S13, it is determined whether or not the auxiliary information mode is selected (ON). If the auxiliary information mode is selected (ON), processing for selecting and inputting auxiliary information is performed (S14). In step S15, the azimuth information storage unit 43 stores the azimuth correction amount together with the azimuth correction amount. On the other hand, when the auxiliary information mode is not selected (OFF) (N in S13), only the azimuth correction amount is stored in the azimuth information storage means 43.

By the way, in the process of calculating the azimuth correction amount as described above, when the photographer acquires the reference image, the reference image is erroneously used by using the display image of the display device 12 instead of the field of view of the optical observation optical system. If acquired, the azimuth shift of the observation optical system will not be reflected.
Therefore, in the digital camera 1 of the present embodiment, when executing the calculation process for calculating the azimuth correction amount, the photographer erroneously displays the display device 12 by executing the process shown in FIG. An erroneous operation of taking a reference image for calculating the azimuth correction amount using the image is prevented.

FIG. 8 is a flowchart showing processing executed when the digital camera 1 calculates the azimuth correction amount. The following processing is also realized by the control means 45 executing. In addition, it is assumed that a display device mode and a message mode, which will be described later, are set to ON in advance.
In this case, the control means 45 determines whether or not the display device mode is ON (S21), and if it is ON, turns off the image display of the display device 12 (S22). That is, the captured image is not displayed on the display device 12 as shown in FIG.
Next, it is determined whether or not the message mode is ON (S23). If the message mode is ON, the display device 12 is prompted to take a reference image using the eyepiece window 11 of the observation optical system. A message is displayed (S24). For example, a warning message indicating that the reference image acquisition operation is in progress as shown in FIG. 10 or a message indicating the reference image acquisition procedure as shown in FIG. 11 is displayed. Thereafter, the reference image is taken (2S5), and after the photographing is finished, the image display of the display device is turned on (S26), and the process is finished. In this embodiment, a message using characters is taken as an example, but it is also possible to present graphics, images, videos, sounds, etc. in addition to text messages, which are also included in the message range. is there.

As described above, in the digital camera 1 of the present embodiment, the field of view of the observation optical system is originally controlled by controlling the captured image captured by the imaging optical system so as not to be displayed on the display device 12 when the reference image is acquired. It is possible to prevent an erroneous operation such that the photographer erroneously uses the display device 12 to capture the reference image where the reference image is to be obtained.
Further, in the digital camera 1 of the present embodiment, since a message for acquiring a reference image is displayed on the display device 12 on which a captured image is not displayed, the reference image is acquired using the display device 12. The correct operation method can be displayed with characters and diagrams while preventing erroneous operation, so that it is possible to definitely perform the reference image acquisition operation without carrying an instruction manual or the like.

In the above processing example, the photographed image is not displayed on the display device 12, but the photographed image to be displayed on the display device 12 is displayed in a state different from the normal display state. It is also possible to prevent an erroneous operation by making the photographer recognize that there is no image.
For example, as shown in FIG. 12, a photographed image displayed on the display device 12 is not in a normal photographing state for the photographer by reducing the brightness and reducing the contrast, or reducing the saturation and displaying in black and white. Recognize that to prevent misoperation. Further, for example, as shown in FIG. 13, the brightness of the image displayed on the display device 12 is displayed in reverse, that is, so-called negative display, or the image displayed on the display device 12 is displayed in black and white as shown in FIG. However, the same effect can be obtained. Note that the display image processing methods shown in FIGS. 12 to 14 are all known techniques, and the details thereof are omitted.
As described above, in the digital camera 1 according to the present embodiment, when a captured image is displayed on the display device 12 when a reference image is acquired, one or more of brightness, saturation, and hue is set as a normal display state. Therefore, by changing the contrast and hue of the image displayed on the display device 12, it is possible to make the photographer recognize that the image is not in the normal shooting state, and an erroneous operation when acquiring the reference image can be performed. It becomes possible to prevent.

Although not shown in the figure, it is also possible to superimpose and display a message prompting the user to shoot a reference image using the observation optical system on the photographic image in a display state different from the normal display state on the display device 12. It is. In this way, the correct operation method can be displayed with characters and diagrams while preventing the erroneous operation of acquiring the reference image using the display device 12, so that the reference image can be displayed without carrying an instruction manual or the like. The acquisition operation can be performed without fail.
As described above, in the digital camera 1 of the present embodiment, as shown in FIG. 15A, the reference image is taken using the eyepiece window 11 that is the field of view of the observation optical system. Even when the azimuth deviation amount is θ (see FIG. 2), a reference image reflecting the azimuth deviation amount θ of the observation optical system can be obtained as shown in FIG. 16, and the azimuth correction amount calculated from this image is obtained. It becomes possible to perform azimuth correction of an image taken using the observation optical system.

When the external observation device 21 is attached to the digital camera 1 as shown in FIG. 2B, the eyepiece window 22 that is the field of view of the external observation device 21 as shown in FIG. As described above, a reference image reflecting the azimuth shift amount θ of the observation optical system can be obtained as shown in FIG. 16, and the azimuth correction amount calculated from this image is used. Thus, it is possible to perform azimuth correction of an image taken using the observation optical system.
Although not shown, the digital camera 1 is provided with detection means for detecting the attachment of the external observation device 21. When the external observation device 21 is detected, the azimuth when the external observation device 21 is used for photographing. Correction is performed based on the deviation amount. In addition, as a detecting means, such as a device using a mechanical switch, a device that detects a change in electrical resistance through a contact point, a method of reading out electronic information previously incorporated in a single observation optical system, etc. It is possible to apply a known technique such as exchange of information between the interchangeable lenses or exchange of information between the camera and an external strobe.

The figure which showed the external appearance of the digital camera which is embodiment of the imaging device of this invention. The front view which showed the azimuth relationship of the image pick-up element and observation optical system of the digital camera of this embodiment. The figure which showed an example of the visual field frame visual field of an observation optical system, and a picked-up image. The figure which showed an example of the object image | photographed for a reference | standard image acquisition. 1 is a block diagram illustrating a configuration of a digital camera according to an embodiment. The figure which showed an example of the information memorize | stored in an azimuth information storage means. The flowchart which showed the flow of the process at the time of calculating the azimuth correction amount in the digital camera of this embodiment. 6 is a flowchart showing processing executed when calculating the azimuth correction amount in the digital camera of the present embodiment. The figure which showed an example of the display state of the display apparatus at the time of reference | standard image acquisition. The figure which showed an example of the display state of the display apparatus at the time of reference | standard image acquisition. The figure which showed an example of the display state of the display apparatus at the time of reference | standard image acquisition. The figure which showed an example of the display state of the picked-up image displayed on a display apparatus at the time of reference image acquisition. The figure which showed an example of the display state of the picked-up image displayed on a display apparatus at the time of reference image acquisition. The figure which showed an example of the display state of the picked-up image displayed on a display apparatus at the time of reference image acquisition. The figure which showed the relationship between the visual field image of an observation optical system, and the display image of a display apparatus. The figure which showed an example of the reference | standard image.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Digital camera, 2 ... Shooting lens, 3 ... Objective window, 4 ... Flash window, 5 ... Accessory shoe, 6 ... Shutter button, 11, 23 ... Eyepiece window, 12 ... Display apparatus, 13 ... Operation button, 20 ... Imaging Elements: 21 ... External observation device, 22 ... Target mark, 30 ... Shooting system block, 31 ... Shooting optical system, 32 ... Observing optical system 40 ... Azimuth processing block, 41 ... Image recording means, 42 ... Azimuth information calculating means, 43 ... Azimuth information storage means, 44 ... Image processing means, 45 ... Control means, 46 ... Auxiliary information input means

Claims (6)

At least an observation optical system for observing a photographing range, an image sensor that outputs a subject image formed by the photographing optical system as electrical image data, and display means for displaying a photographed image photographed by the image sensor And calculating a azimuth correction amount between the imaging element and the observation optical system from a reference image obtained by determining the horizontal or vertical of the subject using the field of view of the observation optical system, and calculating the azimuth correction calculated An imaging apparatus that corrects azimuth of a captured image using a quantity,
An imaging apparatus comprising: control means for controlling the display means to not display an image formed and output on an imaging device by the imaging optical system when acquiring the reference image.   The imaging apparatus according to claim 1, wherein the control unit performs display control for displaying a procedure for acquiring the reference image on the display unit when the reference image is acquired.   When the control unit displays the captured image on the display unit when acquiring the reference image, one or more of brightness, saturation, and hue is in a display state different from a normal display state. The imaging apparatus according to claim 1, wherein the imaging apparatus is controlled as follows.   The control means, when acquiring the reference image, displays the reference image acquisition procedure superimposed on a captured image in a display state different from a normal display state on the display means. Item 4. The photographing apparatus according to Item 3.   The imaging apparatus according to any one of claims 1 to 4, wherein the observation optical system is a built-in built-in observation optical system or an externally attachable single observation optical system.   6. A detecting means for detecting attachment of the single observation optical system, wherein a reference image of the single observation optical system can be acquired when the single observation optical system is detected. The imaging device described in 1.

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