JP2012023468A - Imaging device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To appropriately exaggerate a blurred state in a through image at the time of manual focusing, easily confirm a focused state with high accuracy and high speed, and easily perform focusing.
An object image acquired by an image sensor 101 is displayed on a LCD monitor 10 in real time as a through image. When the focus evaluation value peak is detected during manual focusing, the maximum value of the focus evaluation value is compared with the latest value of the focus evaluation value. If it exceeds, the second image pickup signal processing block 104-2 displays the through image with exaggeration of the blur of the through image by an amount corresponding to the magnitude of the difference. When the peak of the focus evaluation value is not detected, the through signal is displayed with the imaging signal processing block 104-2 exaggerating the blur of the through image by a predetermined amount.
[Selection] Figure 1

Description

  The present invention relates to an imaging apparatus suitable for a so-called digital camera, digital video camera, and the like that records image information obtained by imaging a still image, a movie image, and the like using an imaging element, and in particular, manual focusing. The present invention relates to an imaging device that improves display processing in operation.

In a digital still camera that captures an image of an object by an image sensor such as a CMOS (Complementary Metal Oxide Semiconductor) image sensor or a CCD (Charge Coupled Device) image sensor and obtains an image of the object consisting of digital image data, a contrast signal is obtained from the image signal A focus adjustment method is known in which a high-frequency component corresponding to is extracted and a focus lens for focusing is moved to a lens position where the high-frequency component is maximized.
Information such as a high-frequency component corresponding to such a contrast signal is generally referred to as a focus evaluation value, and the automatic focusing (AF) technology using the focus adjustment method as described above is a hill-climbing automatic focusing method. It is known as the Koji system.
Such a focus adjustment method cannot detect the peak of the focus evaluation value unless a scanning operation for moving and scanning the focus lens is performed, and the peak position is not specified. There are scenes where it is easy to miss a photo opportunity.
Digital still cameras having a manual focusing (manual focusing to MF) mode in which a focus lens is driven by manual operation to perform focusing and shooting are widely used as means for dealing with the above-described problems.

In such a manual focusing mode, a digital still camera of a type that does not have an optical viewfinder that enables a subject to be seen through an optical system used for imaging, like a so-called single-lens reflex (single-lens reflex) camera. Then, focus adjustment is performed while confirming a through image output to a monitor such as a liquid crystal display (LCD) or an electronic viewfinder (EVF).
However, in general, a monitor such as a liquid crystal display or an electronic viewfinder mounted on an imaging apparatus has a relatively low display resolution, and it is determined whether or not the target subject is in focus from the image displayed on the monitor. It is not easy to judge accurately.
For example, even if a monitor with a high display resolution is used, the display screen size of the monitor in the digital still camera itself is small, and from the characteristics of this type of product, it is possible to make the display screen size larger than the currently used size. It is difficult, and it is not easy to check whether or not the image is in focus by the display image on the monitor.
As a technique for coping with such a problem, an imaging apparatus having a function of enlarging and displaying an image to be displayed on a monitor is provided.

When the display image on the monitor is enlarged, only a part of the image is displayed, so that it is not possible to hear the whole state and it is not easy to take a picture with a targeted composition. In addition, regardless of the presence or absence of the enlargement function, there is a problem that the quality of the through image in a dark situation such as nighttime is often noisy and it is difficult to confirm the focus.
On the other hand, an example of another solution is disclosed in Patent Document 2 (Japanese Patent Laid-Open No. 2006-301080). In the method disclosed in Patent Document 2 (Japanese Patent Application Laid-Open No. 2006-301080), after performing focus adjustment roughly by manual focusing operation, automatic focusing by a hill-climbing method is performed in a sufficiently narrow range, thereby performing normal focusing. Focusing is performed faster than automatic focusing.
However, the method disclosed in Patent Document 2 (Japanese Patent Application Laid-Open No. 2006-301080) also involves a scanning operation, so it is difficult to capture a subject immediately at the timing when the user really wants to release the shutter.
Furthermore, a method for solving these problems is disclosed in, for example, Japanese Patent Application Laid-Open No. 2007-96753. In the method disclosed in Patent Document 1 (Japanese Patent Laid-Open No. 2007-96753), the sharpness and blur of a through image displayed on a monitor such as a liquid crystal display or an electronic viewfinder are exaggerated and displayed.

However, the method disclosed in Patent Document 1 (Japanese Patent Laid-Open No. 2007-96753) has the following problems.
(1) In the method disclosed in Patent Document 1 (Japanese Patent Application Laid-Open No. 2007-96753), a focus evaluation value is acquired for a plurality of points on a screen, and a sharpness process is performed to exaggerate the sharpness by using these values. The image is divided into regions to be subjected to blurring processing for exaggerating blur, and each exaggeration processing is performed. Patent Document 1 (Japanese Patent Application Laid-Open No. 2007-96753) is not clearly disclosed, but probably has a certain threshold value, and when the focus evaluation value is larger than the threshold value, sharpness processing is performed. When the focus evaluation value is smaller than the threshold value, it can be interpreted that blurring processing is performed. However, Patent Document 1 (Japanese Patent Laid-Open No. 2007-96753) discloses a focus that differs depending on the brightness of the subject environment and the difference in the subject. It is not specified how to determine the threshold value for the evaluation value, and it is not shown whether the threshold value is a fixed value or a variable value. In general, the focus evaluation value at the most focused position for the same subject at the same distance varies depending on the brightness of the environment. For example, when the contrast of the screen displayed as a through image is reduced due to factors such as darkening of ambient light, the peak of the evaluation value is lowered.

Further, the peak of the evaluation value at the most focused position is different for each subject. If the threshold for determining whether to perform sharpness processing or blurring processing is fixed, the blurring processing is performed even though the focus is best, or it is considerably blurred. However, the number of cases in which sharpness processing is performed increases, and the operation is substantially different from the desired operation. Further, if the threshold value is changed in accordance with the ambient light or the subject, the fact and the specific control method of the threshold value should be clearly specified. However, Patent Document 1 (Japanese Patent Application Laid-Open No. 2007-96753) discloses. There is no such description.
(2) At the time when the through image display is started at the time of manual focusing photographing, the focus lens is located at an arbitrary position, and only the focus evaluation value at the focus lens position can be obtained. Therefore, since it is unclear whether any point on the screen is in focus at that point in time (whether the focus evaluation value is the highest) or not, determination of sharpness processing or blurring processing is made at this point. It is impossible to do.
However, Patent Document 1 (Japanese Patent Laid-Open No. 2007-96753) hardly discloses the behavior at the start of manual focusing. For example, as shown in the embodiment of Patent Document 1 (Japanese Patent Application Laid-Open No. 2007-96753), it is assumed that the automatic focusing operation is performed before the manual focusing operation is performed. Unless it is after the focusing operation, it is impossible to determine whether or not the subject is in focus, so that the manual focusing function is remarkably deteriorated. In particular, in hand-held shooting in which it is easy to change the composition, the function cannot withstand actual use.

(3) When performing a manual focusing operation, the user usually performs a focusing operation while paying attention to one point on the screen. If sharpness processing or blurring processing is performed up to a point that the user is not paying attention to, the user's consciousness to concentrate on one point on the screen is lost, and the function becomes difficult to use.
(4) In order to obtain in-focus evaluation values at a plurality of points on the screen, or to divide the screen into a plurality of parts and to perform sharpness processing or blurring processing for each area, it is expensive with high computing power System is required. These are generally disadvantageous systems for power saving.
(5) Assuming that the most in-focus position desired by the user has been determined, the image displayed on the monitor as a through image is in a state where both sharpness and blur are exaggerated. Therefore, the difference from the image obtained by shooting the still image becomes too large, and it is difficult to imagine the finish at the time of shooting.
(6) Since the process is not performed for one point that the user is paying attention to, the user is provided with an operation guide for detecting that the user has made an error or leading to the result desired by the user. I can't.

As described above, in the manual focusing mode in which the focus lens is driven by manual operation and focused to perform imaging, as disclosed in Patent Document 1 (Japanese Patent Application Laid-Open No. 2007-96753) and the like, focusing is performed. For convenience, the sharpness and blurred state of the live view image are exaggerated to solve the problem in the method of displaying on a monitor such as a liquid crystal display or an electronic viewfinder, and the in-focus state can be easily confirmed with high accuracy and high speed. It was hoped that.
The present invention has been made in view of the circumstances described above, and in manual focusing, appropriately exaggerating the blurred state in the through image, and can easily confirm the in-focus state with high accuracy and high speed. An object of the present invention is to provide an imaging apparatus that can easily perform focusing.
According to the first aspect of the present invention, it is possible to easily check the in-focus state with high accuracy and high speed according to the blurred state in the through image displayed on the monitor during manual focusing, and to easily focus. An object of the present invention is to provide an imaging device that can be used.

An object of claim 2 of the present invention is to make it possible to easily grasp and confirm the in-focus state easily, with high accuracy and at high speed, in particular, depending on the degree of blurring of the entire through image displayed on the monitor. Is to provide.
The object of claim 3 of the present invention is to display a through image exaggerated by Gaussian blurring with a coefficient corresponding to a deviation from the maximum value of the focus evaluation value on a monitor, and easily and accurately. Another object of the present invention is to provide an imaging apparatus that can grasp and confirm the in-focus state at high speed.
The object of claim 4 of the present invention is to display a through image in which blur is exaggerated by suppressing high frequency components at a frequency corresponding to a deviation from the maximum value of the focus evaluation value on a monitor. An object of the present invention is to provide an imaging apparatus capable of grasping and confirming an in-focus state with high accuracy and high speed.
The object of claim 5 of the present invention is to display a through image exaggerated in blur on a monitor at a higher speed, and to easily grasp and confirm the in-focus state with high accuracy and high speed. An imaging device is provided.
The object of claim 6 of the present invention is to display the focus evaluation value acquisition position on the display screen of the through image so that it can be easily changed, and to grasp the focus state with high accuracy and high speed. An object of the present invention is to provide an imaging apparatus that can be confirmed.

The object of claim 7 of the present invention is to reset the presence / absence and maximum value of the focus evaluation value to the initial state as needed, to prevent the display from becoming inappropriate, and with high accuracy. Another object of the present invention is to provide an imaging apparatus that can grasp and confirm the in-focus state at high speed.
The object of claim 8 of the present invention is to acquire the presence / absence and maximum value of the focus evaluation value appropriately at the time of resetting to prevent the display from becoming inappropriate, and to achieve high accuracy and high speed alignment. An object of the present invention is to provide an imaging apparatus capable of grasping and confirming a focus state.
An object of claim 9 of the present invention is to select whether or not to perform blur exaggerated display processing, if desired, and to grasp and confirm the in-focus state with high accuracy and high speed as necessary. An object of the present invention is to provide an image pickup apparatus that enables the above.
An object of claim 10 of the present invention is to be able to select and set the amount of blur exaggeration in the blur exaggeration display process as desired, and to grasp and confirm the in-focus state with high accuracy and high speed. An object of the present invention is to provide an imaging device that can be used.
The object of the eleventh aspect of the present invention is to be able to select and set the sensitivity of the magnitude of the blur exaggeration according to the deviation from the maximum value of the focus evaluation value in the blur exaggeration display process as desired. It is another object of the present invention to provide an imaging apparatus that can grasp and confirm the in-focus state with high accuracy and high speed.

An object of claim 12 of the present invention is to provide an image pickup apparatus that presents to a user whether or not an operation direction in manual focusing is appropriate, and can perform focusing easily and at high speed. .
An object of the thirteenth aspect of the present invention is to provide an imaging apparatus that can selectively switch between manual focusing and automatic focusing by a user operation.

In order to achieve the above-described object, an imaging apparatus according to the present invention described in claim 1
An imaging lens that includes a focus lens for focusing adjustment, and that forms a subject optical image;
Imaging means for acquiring a subject image by converting an optical image of the subject formed by the imaging lens into image data by an imaging element;
Through image display means for displaying the subject image acquired by the imaging means on a monitor in real time as a through image;
Manual focusing means for driving the focus lens of the imaging lens according to a manual operation;
Focusing evaluation information acquisition means for acquiring a focusing evaluation value from a predetermined position in the subject image;
Peak detection means for detecting the peak of the focus evaluation value acquired by the focus evaluation information acquisition means;
When a peak of the focus evaluation value is detected by the peak detection unit during manual operation of the focus lens by the manual focusing unit, the maximum value of the focus evaluation value and the latest of the focus evaluation value If the magnitude of the difference between the two exceeds a predetermined value, the through image is exaggerated by an amount corresponding to the magnitude of the difference, and the through image is displayed. A blur exaggeration display processing unit that exaggerates the blur of the through image by a predetermined amount and displays the through image when the peak of the focus evaluation value is not detected by the peak detection unit. It is a feature.

An imaging device according to the present invention described in claim 2 is the imaging device according to claim 1,
The blur exaggeration display processing means is a means for changing a blur exaggeration amount of the through image in proportion to the difference in the focus evaluation value.
An imaging device according to the present invention described in claim 3 is the imaging device according to claim 2,
The blur exaggeration display processing means is means for exaggerating blur of the through image by Gaussian blur processing and changing a coefficient of the blur exaggeration amount in proportion to the difference of the focus evaluation values. Yes.
The imaging device according to the present invention described in claim 4 is the imaging device according to claim 2,
The blur exaggeration display processing means is means for exaggerating blur of the through image by blurring processing for suppressing high frequency components and changing the threshold frequency to be suppressed in proportion to the difference of the focus evaluation values. It is characterized by.
An imaging device according to the present invention described in claim 5 is the imaging device according to any one of claims 1 to 4,
The blur exaggerated display processing means is implemented as a processing circuit made of hardware.

An imaging device according to a sixth aspect of the present invention is the imaging device according to any one of the first to fifth aspects,
It further comprises means for superimposing and displaying the focus evaluation value acquisition position on the display screen of the through image, and means for easily changing the focus evaluation value acquisition position to an arbitrary position. It is said.
An imaging device according to a seventh aspect of the present invention is the imaging device according to any one of the first to sixth aspects,
When the blur exaggerated display processing unit starts the blur exaggerated display processing and when a predetermined operation is performed during the blur exaggerated display processing, the presence or absence of the peak of the focus evaluation value in the peak detecting unit and the alignment A reset processing means for resetting the maximum value of the focus evaluation value is further included.
The imaging device according to the present invention described in claim 8 is the imaging device according to claim 7,
The reset processing means finely drives the focus lens for a predetermined range in the vicinity of the focus position at that time, whether there is a peak of the focus evaluation value within the predetermined range, and the maximum of the focus evaluation value within the predetermined range It is a means for determining a value.

The imaging device according to the present invention described in claim 9 is the imaging device according to any one of claims 1 to 8,
The display device further includes means for selecting whether or not to perform the blur exaggerated display processing by the blur exaggerated display processing means by a user operation.
An imaging device according to a tenth aspect of the present invention is the imaging device according to any one of the first to ninth aspects,
A plurality of patterns corresponding to differences in the strength of blur exaggeration are prepared in advance for the magnitude of the blur exaggeration amount in the blur exaggeration display processing by the blur exaggeration display processing means, and from these plural patterns, a user operation The method further includes means for selecting.
An imaging device according to the present invention described in claim 11 is the imaging device according to any one of claims 1 to 10,
The sensitivity of the blur exaggerated display process corresponding to the difference between the maximum value of the focus evaluation value and the latest value at which the blur exaggerated display process is to be started in the blur exaggerated display process by the blur exaggerated display processing means is a plurality of stages It is characterized by further comprising means for preparing values in advance and selecting from these multiple stages by user operation.

An imaging device according to a twelfth aspect of the present invention is the imaging device according to any one of the first to eleventh aspects,
During manual operation of the focus lens by the manual focusing means, the user's operation direction is determined from the change in the focus evaluation value acquired by the focus evaluation information acquisition means, and the focus evaluation value is reduced. It further includes operation direction warning means for generating a warning that the operation direction is not appropriate at the time of operation, and means for selecting whether or not to perform this operation direction warning by user operation.
An imaging device according to a thirteenth aspect of the present invention is the imaging device according to any one of the first to twelfth aspects,
Based on the focus evaluation value acquired from the predetermined position in the subject image by the focus evaluation information acquisition means and the focus evaluation value acquired by the focus evaluation information acquisition means, the peak detection means detects the focus evaluation information. Automatic focusing means for driving and controlling the focus lens to focus on the subject using the peak position of the focusing evaluation value.
The apparatus further includes means for selecting one of focusing by the manual focusing means and automatic focusing by the automatic focusing means by a user operation.

According to the present invention, in manual focusing, it is possible to appropriately exaggerate the blurred state in the through image, easily check the in-focus state with high accuracy, and easily perform focusing. An imaging apparatus can be provided.
That is, according to the imaging device of claim 1 of the present invention,
An imaging lens that includes a focus lens for focusing adjustment, and that forms a subject optical image;
Imaging means for acquiring a subject image by converting an optical image of the subject formed by the imaging lens into image data by an imaging element;
Through image display means for displaying the subject image acquired by the imaging means on a monitor in real time as a through image;
Manual focusing means for driving the focus lens of the imaging lens according to a manual operation;
Focusing evaluation information acquisition means for acquiring a focusing evaluation value from a predetermined position in the subject image;
Peak detection means for detecting the peak of the focus evaluation value acquired by the focus evaluation information acquisition means;
When the peak of the focus evaluation value is detected by the peak detection unit during manual operation of the focus lens by the manual focusing unit, the maximum value of the focus evaluation value and the latest of the focus evaluation value If the magnitude of the difference between the two exceeds a predetermined value, the through image is exaggerated by an amount corresponding to the magnitude of the difference, and the through image is displayed. A blur exaggeration display processing unit for exaggerating the blur of the through image by a predetermined amount and displaying the through image when the peak of the focus evaluation value is not detected by the peak detection unit; ,
During manual focusing, the in-focus state can be easily confirmed with high accuracy and high speed by the blur state in the through image displayed on the monitor, and focusing can be easily performed.

According to the imaging device of claim 2 of the present invention, in the imaging device of claim 1,
The blur exaggerated display processing means is a means for changing a blur exaggeration amount of the through image in proportion to the difference in the focus evaluation value.
In particular, it is possible to easily grasp and confirm the in-focus state with high accuracy and high speed according to the degree of blurring of the entire through image displayed on the monitor.
According to the imaging device of claim 3 of the present invention, in the imaging device of claim 2,
The blur exaggeration display processing means exaggerates the blur of the through image by Gaussian blur processing, and changes the coefficient of the blur exaggeration amount in proportion to the difference in the focus evaluation value.
In particular, a through image in which blur is exaggerated by Gaussian blurring with a coefficient corresponding to the deviation from the maximum focus evaluation value is displayed on the monitor, and the in-focus state can be easily grasped and confirmed with high accuracy and at high speed. It becomes possible.

According to the imaging device of claim 4 of the present invention, in the imaging device of claim 2,
The blur exaggeration display processing means is means for exaggerating blur of the through image by blurring processing for suppressing high frequency components and changing the threshold frequency to be suppressed in proportion to the difference of the focus evaluation values. By
In particular, the through image exaggerated by suppression of high-frequency components at a frequency corresponding to the deviation from the maximum focus evaluation value is displayed on the monitor, and the focus state can be easily and accurately grasped at high speed. It becomes possible to confirm.
Moreover, according to the imaging device of Claim 5 of this invention, In the imaging device of any one of Claims 1-4,
The blur exaggerated display processing means is implemented as a processing circuit made of hardware.
In particular, the through image exaggerated in blur can be displayed on the monitor at a higher speed, and the in-focus state can be easily grasped and confirmed with high accuracy and at a high speed.

According to the imaging device of claim 6 of the present invention, in the imaging device of any one of claims 1 to 5,
By further including means for superimposing and displaying the acquisition position of the focus evaluation value on the display screen of the through image, and means for easily changing the acquisition position of the focus evaluation value to an arbitrary position.
In particular, the acquisition position of the focus evaluation value can be displayed on the display screen of the through image so as to be easily changeable, and the focus state can be grasped and confirmed with high accuracy and at high speed.
According to the imaging device of claim 7 of the present invention, in the imaging device of any one of claims 1 to 6,
When the blur exaggerated display processing unit starts the blur exaggerated display processing and when a predetermined operation is performed during the blur exaggerated display processing, the presence or absence of the peak of the focus evaluation value in the peak detecting unit and the alignment By further including reset processing means for resetting the maximum value of the focus evaluation value,
In particular, if necessary, reset the peak value of the focus evaluation value and the maximum value to the initial state to prevent the display from becoming inappropriate, and grasp and check the focus state with high accuracy and high speed. It becomes possible.

According to the imaging device of claim 8 of the present invention, in the imaging device of claim 7,
The reset processing means finely drives the focus lens for a predetermined range in the vicinity of the focus position at that time, whether there is a peak of the focus evaluation value within the predetermined range, and the maximum of the focus evaluation value within the predetermined range By being a means of determining the value,
In particular, it is possible to appropriately acquire the presence or absence and maximum value of the focus evaluation value at the time of reset, prevent display from becoming inappropriate, and grasp and check the focus state with high accuracy and high speed. Become.
According to the imaging device of claim 9 of the present invention, in the imaging device of any one of claims 1 to 8,
By further including means for selecting by a user operation whether or not to perform blur exaggerated display processing by the blur exaggerated display processing means,
In particular, it is possible to select whether or not to perform the blur exaggerated display process as desired, and to grasp and confirm the in-focus state with high accuracy and high speed as necessary.

According to the imaging device of claim 10 of the present invention, in the imaging device of any one of claims 1 to 9,
A plurality of patterns corresponding to differences in the strength of blur exaggeration are prepared in advance for the magnitude of the blur exaggeration amount in the blur exaggeration display processing by the blur exaggeration display processing means, and from these plural patterns, a user operation By further including means for selecting,
In particular, the magnitude of the blur exaggeration amount in the blur exaggeration display process can be selected and set as desired, and the in-focus state can be grasped and confirmed with high accuracy and at high speed.
According to the imaging device of claim 11 of the present invention, in the imaging device of any one of claims 1 to 10,
The sensitivity of the blur exaggerated display process corresponding to the difference between the maximum value of the focus evaluation value and the latest value at which the blur exaggerated display process is to be started in the blur exaggerated display process by the blur exaggerated display processing means is a plurality of stages By preparing a value in advance and further including means for selecting by a user operation from these multiple stages,
In particular, the sensitivity of the amount of blur exaggeration according to the deviation from the maximum value of the focus evaluation value in the blur exaggeration display process can be selected and set as desired, and the in-focus state with high accuracy and high speed It becomes possible to grasp and confirm.

According to the imaging device of claim 12 of the present invention, in the imaging device of any one of claims 1 to 11,
During manual operation of the focus lens by the manual focusing means, the user's operation direction is determined from the change in the focus evaluation value acquired by the focus evaluation information acquisition means, and the focus evaluation value is reduced. By further including an operation direction warning means for generating a warning that the operation direction is not appropriate at the time of operation, and a means for selecting whether to perform this operation direction warning by a user operation,
In particular, it is possible to present to the user whether or not the operation direction in manual focusing is appropriate, and to perform focusing easily and at high speed.
According to the imaging device of claim 13 of the present invention, in the imaging device of any one of claims 1 to 12,
Based on the focus evaluation value acquired from the predetermined position in the subject image by the focus evaluation information acquisition means and the focus evaluation value acquired by the focus evaluation information acquisition means, the peak detection means detects the focus evaluation information. Automatic focusing means for driving and controlling the focus lens to focus on the subject using the peak position of the focusing evaluation value.
By further including means for selecting one of the focusing by the manual focusing means and the automatic focusing by the automatic focusing means by a user operation;
In particular, it is possible to selectively switch between manual focusing and automatic focusing by a user operation.

It is a block diagram which shows typically the electromechanical system structure of the principal part of the control system of the digital camera to which one embodiment of this invention is applied. It is a top view which shows typically the state which looked at the external appearance structure of the digital camera of FIG. 1 from the upper surface side. FIG. 2 is a front view schematically showing a state in which the external configuration of the digital camera of FIG. 1 is viewed from the front subject side. It is a rear view which shows typically the state which looked at the external appearance structure of the digital camera of FIG. 1 from the back surface photographer side. 3 is a flowchart of blur exaggeration display processing in the digital camera of FIG. 1. 2A and 2B are schematic diagrams for explaining the concept of a focus evaluation value acquisition area in the digital camera of FIG. 1, in which FIG. 1A shows the positional relationship between the digital camera and a subject, and FIG. The focus evaluation value acquisition area and the subject image in the image displayed on the rear monitor are shown. 2A and 2B are diagrams for explaining the effect of the blur exaggeration display process in the digital camera of FIG. 1, in which FIG. 1A is a graph showing a relationship between a focus evaluation value and a focus distance, and FIG. It is a figure which shows the relationship between each state when not present, and monitor display, and (c) is a figure which shows the relationship between each state when performing a blurring process, and monitor display. FIG. 2 is a schematic diagram for explaining the concept of reset processing of a maximum focus evaluation value in the case of a single subject in the digital camera of FIG. 1, and (a) shows the positional relationship between the digital camera and the subject. (B) is a graph showing the relationship between the focus evaluation value and the focus distance, and (c) is a diagram showing the relationship between each state and the monitor display when performing blurring processing. . FIG. 2 is a schematic diagram for explaining a concept of reset processing of a maximum focus evaluation value when subjects in the digital camera of FIG. 1 overlap, and (a) shows a positional relationship between the digital camera and the subject. (B) is a graph showing the relationship between the focus evaluation value and the focus distance, and (c) is a diagram showing the relationship between each state and the monitor display when performing blurring processing. . 2A and 2B are diagrams for explaining a setting screen when setting a blur amount in the digital camera of FIG. 1, in which FIG. 1A shows a blur amount setting state, and FIG. 1B shows a blur state setting change state; Show. 2A and 2B are diagrams for explaining a setting screen when setting a blur sensitivity in the digital camera of FIG. 1, in which FIG. 1A shows a blur sensitivity setting state, and FIG. 1B shows a blur amount setting change state; Show. It is a figure for demonstrating an example of the operation direction error warning display process to the monitor screen in the digital camera of FIG. It is a figure for demonstrating another example of the operation direction error warning display process to the monitor screen in the digital camera of FIG. 1, (a) is the state which looked at the state which looked at the external appearance structure of the digital camera from the front subject side. And (b) is a diagram showing a monitor screen on which an operation direction error warning is displayed.

Hereinafter, based on one embodiment of the present invention, an imaging device of the present invention will be described in detail with reference to the drawings.
Here, although an embodiment of a digital camera as an imaging device is described, the present invention is not limited to this, and an image for processing an image related to an electronic device having a camera function or an imaging device is described. The present invention can be applied to general image processing such as a processing IC (integrated circuit) and image processing software.
1 to 4 show a schematic configuration of a digital camera as an imaging apparatus according to an embodiment of the present invention. FIG. 1 is a block diagram schematically showing an outline of a system configuration of a control system of a digital camera. 2 is a schematic plan view of the external configuration of the digital camera of FIG. 1 as viewed from above. FIG. 3 is a schematic front view of the external configuration of the digital camera of FIG. 4 is a schematic rear view of the external configuration of the digital camera of FIG. 1 as viewed from the rear photographer side.
As shown in FIGS. 2 to 4, the digital camera shown in FIGS. 1 to 4 has a sub liquid crystal display (sub LCD) 1, a release button 2, a mode switching dial 3, an optical viewfinder 4, and a strobe light emitting unit. 5, remote control light receiving unit (remote control light receiving unit) 6, lens barrel unit 7, autofocus display light emitting diode (AF display LED) 8, strobe display light emitting diode (strobe display LED) 9, liquid crystal display monitor (LCD monitor) 10, A wide-angle (WIDE) zoom button 11, a telephoto (TELE) zoom button 12, a power switch 13, an operation button group 14, and a memory card / battery storage unit 15 are provided.

Further, the digital camera shown in FIGS. 1 to 4 has the above-mentioned sub LCD 1, strobe light emitting unit 5, remote control light receiving unit 6, lens barrel unit 7, as shown in FIG. In addition to the AF display LED 8, the strobe display LED 9 and the LCD monitor 10, the image sensor 101, front end unit 102, SDRAM (synchronous dynamic random access memory) 103, camera processor 104, RAM (random access memory) 107, ROM (Read only memory) 108, sub CPU (sub central processing unit) 109, operation unit 110, sub LCD driver 111, buzzer 113, strobe circuit 114, audio recording unit 115, audio reproduction unit 116, LCD driver 117, video amplifier ( Video amplifier) 1 8, a video connector 119, internal memory 120, a memory card slot 121, USB (Universal Serial Bus) connector 122, a serial interface unit 123, a wired / wireless Ethernet circuit 130 and LAN connector 131.
The lens barrel unit 7 includes a zoom optical system 7-1 including a zoom lens system 7-1a and a zoom motor 7-1b, a focus optical system 7-2 including a focus lens system 7-2a and a focus motor 7-2b, and a diaphragm 7. -3a and a diaphragm motor 7-3b, a shutter unit 7-4 including a shutter 7-4a and a shutter motor 7-4b, and a motor driver 7-5.

The front end unit 102 includes a CDS (correlated double sampling unit) 102-1, an AGC (automatic gain control unit) 102-2, an A / D (analog-digital) conversion unit 102-3, and a TG (timing generator) 102-. 4.
The camera processor 104 includes a first imaging signal processing block 104-1, a second imaging signal processing block 104-2, a CPU (central processing unit) block 104-3, and a local SRAM (local static random access memory) 104-4. USB processing block 104-5, serial processing block 104-6, JPEG codec (CODEC) block 104-7, resizing block 104-8, video signal display block 104-9 and memory card controller block 104-10 Have.
The operation unit 110 includes a release button 2, a mode switching dial 3, a WIDE zoom button 11, a TELE zoom button 12, a power switch 13, and an operation button group 14 shown in FIG.
The audio recording unit 115 includes an audio recording circuit 115-1, a microphone amplifier 115-2, and a microphone (microphone) 115-3. The audio reproducing unit 116 includes an audio reproducing circuit 116-1, an audio amplifier (audio amplifier). ) 116-2 and speaker 116-3. The serial interface unit 123 includes a serial driver circuit 123-1 and a serial connector 123-2.

The sub LCD 1, the release button 2 and the mode switching dial 3 are arranged on the upper surface of the camera body. The sub LCD 1 is used as a display unit for displaying, for example, the number of shootable images. The release button 2 can be pressed in two stages, and an automatic focusing (AF) operation can be performed by pressing the first stage, and a shooting operation can be performed by pressing the second stage. In general, pressing the first step is referred to as “half pressing”, and pressing the second step is referred to as “full pressing”.
The objective surface of the optical viewfinder 4, the strobe light emitting unit 5, the remote control light receiving unit 6, and the lens barrel unit 7 are arranged on the front side of the camera body. A memory card such as an SD card and a memory card / battery storage unit 15 for loading a battery are disposed on the left side as viewed from the object (subject) side of the camera body. A memory card slot 121 is provided inside the memory card / battery storage unit 15, and the memory card is loaded by inserting the memory card into the memory card slot 121. A battery loading unit (not shown) is also provided inside the memory card / battery storage unit 15, and a battery is loaded into this battery loading unit.

Further, the eyepiece of the optical viewfinder 4, the AF display LED 8, the strobe display LED 9, the LCD monitor 10, the WIDE zoom button 11, the TELE zoom button 12, the power switch 13 and the operation button group 14 are arranged on the rear side of the camera body. Has been placed.
The operation button group 14 includes a play button, a frequently used self-timer / delete button, a menu (MENU) / OK button, an up / strobe button, a down / macro button, a left / image confirmation button, a right button, and an image. Includes display buttons to display. The self-timer / delete button is frequently used. The up / strobe button, down / macro button, left / image confirmation button, and right button constitute up / down / left / right buttons corresponding to the cross key.
In this digital camera, it is possible to shift to the manual focusing mode by displaying a screen for performing various settings by operating the MENU button and operating the up / down / left / right buttons in this state. After selecting the manual focusing mode, the through image can be displayed again by operating the MENU button. In a state where a through image is displayed in the manual focusing mode, the position of the focus lens 7-2a can be driven to an arbitrary position along the optical axis direction by the up and down buttons.

Next, an outline of the control system of the digital camera shown in FIGS. Here, the portions necessary for understanding the present invention are mainly described in detail, and portions not so important for understanding the present invention are not necessarily described in detail.
The zoom lens system 7-1a of the zoom optical system 7-1 and the focus lens system 7-2a of the focus optical system 7-2 in the lens barrel unit 7 constitute an imaging optical system, and an optical image of the subject is captured by the imaging element. An image is formed on the light receiving surface 101. The motor driver 7-5 is controlled by the CPU block 104-3 of the camera processor 104, and the zoom drive motor 7-1b, focus drive motor 7-2b, aperture motor 7-3b, and shutter motor 7-4b in the lens barrel unit 7. Drive.
The image pickup device 101 is configured using a solid-state image pickup device such as a CMOS (complementary metal oxide semiconductor) image sensor or a CCD (charge coupled device) image sensor. Capture as an image signal. The front end unit 102 is controlled by the CPU block 104-3 of the camera processor 104. The imaging device 101, the CDS 102-1, the AGC 102-2, and the A are supplied by the TG 102-4 to which the vertical synchronization signal (VD) and the horizontal synchronization signal (HD) are supplied from the first imaging signal processing block 104-1 of the camera processor 104. A drive timing signal for the / D conversion unit 102-3 is generated and driven at a predetermined timing.

The CDS 102-1 performs correlated double sampling on the image signal output from the image sensor 101 to remove image noise. The AGC 102-2 adjusts the gain of the image signal that has been correlated and sampled by the CDS 102-1. The A / D conversion unit 102-3 converts the image signal whose gain has been adjusted by the AGC 102-2 into a digital signal.
In the camera processor 104, the first image signal processing block 104-1 performs white balance adjustment and gamma adjustment on the image data captured by the image sensor 101 and output from the front end unit 102, and as described above. The VD signal and the HD signal are supplied to the TG 102-4 of the front end unit 102. The second imaging signal processing block 104-2 converts the image data into luminance data / color difference data by filtering processing and performs blurring processing, which is a feature of the present invention. The CPU block 104-3 controls the operation of each part of the apparatus as described above. The local SRAM 104-4 temporarily stores data necessary for the above-described control. The video signal display block 104-9 converts the image data into a video signal for display on an external display device such as an LCD monitor 10 or a television (TV) receiver.
In this embodiment, as will be described in detail later, the second image pickup signal processing block 104-2 performs high-speed blurring processing by hardware, but the CPU block 104-3 operates. Blur processing may be performed by software.

The LCD driver 117 is a circuit for driving the LCD monitor 10, and the LCD driver 117 has a function of converting the video signal output from the video signal display block 104-9 into a signal for displaying on the LCD monitor 10. Also have. The LCD monitor 10 is a monitor mainly for displaying an image, and a through display for observing the state of a subject before photographing, a display for confirming a photographed image, and an image recorded in a memory card or a built-in memory 120. Display such as playback display for checking / appreciating data.
Next, the basic operation of the digital camera shown in FIGS. 1 and 2, the strobe light emitting unit 5 and the strobe circuit 114 are used to supplement the light amount when the amount of natural light or the like in the subject is insufficient. That is, for shooting in a dark place or shooting when the subject is dark, the strobe circuit 114 emits the strobe light emitting unit 3 to illuminate the subject by giving a strobe light emission signal from the camera processor 104 to the strobe circuit 114.

For autofocusing (AF) in this type of digital camera, a focusing evaluation value such as a contrast value of a subject image formed on the image sensor 101 by the optical system of the lens barrel unit 7 is detected, and the most focusing evaluation value is obtained. The focus lens 7-2a is moved to a higher position to adjust the focus.
The ROM 108 stores a control program, parameters for control, and the like written in program codes readable by the CPU block 104-3. When the power of the digital camera is turned on by operating the power switch 13 of the operation unit 110, the control program is loaded into a main memory (not shown) attached to the CPU block 104-3. The operation of each part of the apparatus is controlled according to the control program, and data and the like necessary for the control are temporarily stored in the RAM 107 and the local SRAM 104-4 in the camera processor 104. If the ROM 108 is configured using a rewritable flash memory, it is possible to change the control program, parameters for control, and the like, and the function can be easily upgraded.

  As described above, the first imaging signal processing block 104-1 of the camera processor 104 supplies the VD signal and the HD signal to the TG 102-4 of the front end unit 102, and from the imaging element 101 via the front end unit 102. Signal processing such as white balance adjustment and gamma adjustment is performed on the given digital imaging signal data. The second imaging signal processing block 104-2 of the camera processor 104 performs filtering processing on the digital imaging signal data, thereby converting luminance and color difference data from original RGB (RAW-RGB) data, that is, YUV (YCbCr) data. , Etc. The CPU block 104-3 of the camera processor 104 appropriately controls the operation of each part in the camera. As described above, the local SRAM 104-4 of the camera processor 104 temporarily stores data necessary for control by the CPU block 104-3.

  Further, in the camera processor 104, a USB processing block 104-5 is connected to an external device such as a PC (Personal Computer) in accordance with the USB standard, performs USB signal processing for communication with the external device, and a serial block. 104-6 is connected to an external device such as a PC in accordance with a serial communication standard such as RS-232C, and performs serial signal processing for communication with the external device. The JPEG codec block 104-7 includes image data JPEG compression / decompression is performed, the resize block 104-8 enlarges / reduces the size of the image data by an interpolation process such as extrapolation / interpolation, and the video signal display block 104-9 displays the image data on the LCD monitor 10 Converted to a video signal for display on an external display device such as a TV The memory block 104-10 is a memory for recording captured image data to a memory card loaded in the memory card slot 121 in the memory card loading unit 15 and reproducing the captured image data recorded on the memory card. Control card writing / reading.

The SDRAM 103 is used to temporarily store image data when the camera processor 104 performs various processes on the image data. The stored image data is, for example, a state in which white balance adjustment and gamma adjustment are performed on the image data captured from the image sensor 101 via the front end unit 102 in the first image signal processing block 104-1. Original RGB image data or image data captured in the same manner is converted into luminance data (Y) and color difference data (U (Cb), V (Cr)) by the second imaging signal processing block 104-2 YUV (YCbCr) image data, JPEG image data JPEG compression encoded by the JPEG codec block 104-7, and the like.
The memory card slot 121 is a connector slot for detachably loading a memory card for storing photographed image data, and writing / reading control of the memory card loaded in the memory card slot 121 is performed by a memory card. This is done by the memory card controller block 104-10 via the slot 121. The built-in memory 120 is a memory for storing photographed image data, so that the photographed image data can be stored even when no memory card is inserted in the memory card slot 121. Is provided.

The video amplifier 118 impedance-converts the video signal output from the video signal display block 104-9 to a 75Ω impedance output. The video connector 119 is a connector for connecting the 75Ω impedance output of the video amplifier 118 to an external display device such as a TV.
The USB connector 122 is a connector for USB connection with an external device such as a PC. A serial interface unit 123 including a serial driver circuit 123-1 and a serial connector 123-2 is for performing serial communication with an external device such as a PC in accordance with a standardized serial communication standard such as the RS-232C standard. Configure the interface. The serial driver circuit 123-1 is a circuit that converts the voltage of the output signal of the serial processing block 104-6, and the serial connector 123-2 converts the serial output voltage-converted by the serial driver circuit 123-1 to an external device such as a PC. A connector for connecting to a device.
The sub CPU 109 is, for example, a CPU such as a microprocessor having a built-in ROM / RAM on the same chip. The CPU block 104-of the camera processor 104 is output using the output signals from the operation unit 110 and the remote control light receiving unit 6 as user operation information. 3, or a control signal is supplied to the sub LCD 1, the AF display LED 8, the strobe display LED 9, and the buzzer 113 based on the camera state information output from the CPU block 104-3.

The sub LCD 1 is a display unit for displaying, for example, the number of shootable images, and the sub LCD driver 111 is a circuit that drives the sub LCD 1 based on an output signal of the sub CPU 109. The AF display LED 8 is an LED for displaying an in-focus state at the time of shooting, and the strobe display LED 9 is a light emission preparation state such as whether or not the strobe light emitting capacitor is fully charged and can emit light. It is LED for displaying. The AF display LED 8 and the strobe display LED 9 may be used for other display applications, for example, a display indicating that the memory card is being accessed.
The remote control light receiving unit 6 receives an optical signal such as infrared rays from a remote control transmitter (not shown) operated by the user.
In the audio recording unit 115, the user inputs an audio signal through the microphone 115-3, the audio signal input to the microphone 115-3 is amplified by the microphone amplifier 115-2, and the audio amplified by the microphone amplifier 115-2 is amplified. The signal is recorded by the voice recording circuit 115-1. The audio reproduction unit 116 converts the recorded audio signal into a signal for output reproduction from the speaker by the audio reproduction circuit 116-1, and the audio signal converted by the audio reproduction circuit 116-1 is converted into an audio amplifier. The speaker 116-3 is driven by the signal amplified by 116-2 and amplified by the audio amplifier 116-2 to output a sound signal.

Further, as shown in FIG. 1, a wired / wireless Ethernet (registered trademark) circuit 130 and a LAN connector 131 are provided to perform wired and wireless connection to a LAN (local area network) by Ethernet (registered trademark). To be able to.
Next, the configuration and operation that characterize the present invention in the digital camera configured as described above will be specifically described.
Next, an operation in one embodiment to which the present invention is applied in the above-described configuration will be described. Embodiment described here is not limited to it, It can implement in various correction | amendments or deformation | transformation within the range which a person skilled in the art can easily think of.
FIG. 5 shows an overall flow of processing for exaggerating and displaying a through image (hereinafter referred to as “blurred exaggerated display processing”) during manual focusing according to the characteristic operation of the present invention in the digital camera described above. Yes. The blur exaggerated display process will be specifically described below with reference to the flowchart of FIG.
In the process of step S01, the focus evaluation value is acquired from the point designated on the screen in advance by the user. In step S02 and step S03, the presence / absence of the peak of the focus evaluation value and the maximum value of the focus evaluation value are reset to predetermined initial values (corresponding to claims 7 and 8). In particular, the case where the reset process works effectively will be described later with reference to FIGS.

In step S04 and step S05, it becomes a reference when determining whether or not to perform the blurring process in the subsequent steps, and when performing the blurring process, a reference when determining how much the blurring amount is to be performed The “evaluation value maximum value” is updated.
Step S06 is a process for determining the presence or absence of a peak in the focus evaluation value and switching the through image blurring method. Before the peak is detected, the processing from step S07 to step S08 is performed, and after the peak is detected, the processing from step S09 to step S12 is performed.
In step S09, a difference between “maximum evaluation value” and “current evaluation value” for determining the blurring amount is obtained.
Step S10 is a branching process for determining whether or not to perform the process of blurring the through image. The “threshold value” here corresponds to the sensitivity of the blurring process (corresponding to claim 11). Details of this processing will be described later with reference to FIG.
In step S11, if it is determined in step S10 that the “through image is to be blurred”, it is determined how much to blur, and an instruction is given to the second imaging signal processing block 104-2 in FIG. give. Details of this processing will be described later with reference to FIG.

In step S12, when it is determined in step S10 that the “through image is blurred”, the user is warned that the operation direction in which the focus lens has been moved is incorrect, and this is displayed on the screen. Processing (corresponding to claim 12). Details of this processing will be described later with reference to FIG.
In this embodiment, in the flowchart of FIG. 5, a warning is displayed when blurring is performed even once. However, if the warning is too sensitive, it is the same. Regarding the direction operation, a warning is issued when the blurring process is continuously performed n times in advance, or a warning-specific threshold value is provided independently of step S10, and the “evaluation value difference” is greater than the warning-specific threshold value. Consideration may be given, such as warning if it is large.
Step S13 is a process for determining the end of the blur exaggerated display process. If the user performs a predetermined end operation, the process exits the loop. If there is no predetermined end 0 operation, the processing from step S01 to step S12 is repeated again.
In this case, the user can arbitrarily select whether or not to perform the “blurred exaggerated display process” shown in FIG. 5 (see claim 9).

FIG. 6 is an explanatory diagram of points for acquiring the displayed focus evaluation value during the manual focusing operation (corresponding to claim 6). FIG. 6A shows the relationship between the camera and the subject. At this time, it is assumed that the screen is displayed as shown in FIG. A frame at the center of the screen in FIG. 6B shows an area for acquiring a focus evaluation value during manual focusing. This focus evaluation value acquisition area is moved up, down, left and right on the screen by the up / strobe button, down / macro button, left / image confirmation button and right button in the operation button group 14 shown in FIG. It can be set at an arbitrary position.
Although omitted in FIG. 6B and the like, information such as an aperture value and a shutter speed at the time of shooting may be displayed at the same time.
FIGS. 7A to 7C compare the screen states when the blur exaggerated display process is not performed and when the blur exaggerated display process is performed in order to explain the effect of the present invention. Yes.
The graph in FIG. 7A shows the relationship between the focus evaluation value and the distance at which the focus lens is focused. In the case of the subject shown in this example, it is shown that the highest focus evaluation value is obtained when the focus distance is 10 cm.

FIG. 7B shows how the subject is displayed on the screen without performing the blur exaggerated display process at the in-focus distance of <1> to <4> shown in FIG. 7A. This is shown schematically. In <1>, since the evaluation value is a low position, the subject is displayed in a blurred state (7b-1). In <2>, the subject is still displayed blurred although it is less than <1> (7b-2). In <3>, the evaluation value is the highest and the subject is displayed sharply (7b-3). <4> shows that although the evaluation value is slightly lower than <3>, it is not displayed blurred on the screen, and it is difficult to distinguish the difference from <3> (7b-4).
In FIG. 7C, when the blur exaggerated display processing is working, the in-focus distance is <1> → <2> → <3> → <4> → <3> → <2> → <1>. It is the figure which showed typically how a subject is displayed on a screen when it is moved sequentially. If it is assumed that the manual focusing operation is started at the time point <1>, it is determined that there is no peak according to the flowchart of FIG. 5, and a certain amount of blurring occurs (7c-1). Even at the time of <1> → <2>, there is no peak in the same manner, so there is a certain amount of blurring. However, since the focus lens is moved in the direction of climbing the evaluation value mountain compared to <1>, <1> is not blurred by the ability of (7c-2). <2> → <3> is the same as <2>. Although it is the peak of the original focus evaluation value, the lens is not yet moved to the extent that the focus evaluation value is lowered, so it is sharper than <2> even though a certain amount of blurring is applied (7c- 3). At the time of <4>, since the focus lens is moved in a direction lowering the peak of the focus evaluation value compared to <3>, the focus evaluation value peak was passed by the process of step S08 in the flowchart of FIG. It is judged.
As a result, the processes in steps S09 to S12 in FIG. 5 are performed and displayed more blurred than originally (7c-4). That is, the difference between <3> and <4> can be easily discriminated compared with the case where there is no blurring process. At the time of <4> → <3>, the subject is projected most sharply even if the processing in steps S09 to S12 in FIG. 5 is performed (7c-5). Thereafter, at the time of <3> → <2> and <2> → <1>, the focus lens is moved in the direction of going down the peak of the focus evaluation value, so that the blur amount becomes larger and the original blur is not achieved. Is also greatly blurred (7c-6 and 7c-7).
As described above, the blur exaggerated display processing according to this embodiment makes it possible to easily discriminate the difference due to the difference in the in-focus distance between <3> and <4>, thereby improving user operability.
Next, a scene where it is desirable to reset the maximum evaluation value will be described with reference to FIGS. 8 and 9 (corresponding to claims 7 and 8).
First, FIG. 8 will be described. FIG. 8A schematically shows the relationship between the camera and the two subjects A and B. It is assumed that the user performs a manual focusing operation on the subject A, and then performs a manual focusing operation on the subject B that is darker than the subject A.

  The graph of FIG. 8B shows the relationship between the focus evaluation value and the focus distance of each of the subject A and the subject B in the above-described situation. Although subject A and subject B have a peak focus evaluation value at the same distance, subject B in a dark place has a lower peak focus evaluation value than subject A in a bright place. In such a situation, when the camera is pointed at the subject B after focusing on the subject A in the state where the blur exaggerated display process shown in FIG. 5 is operated, the subject B as shown by 8c-1 in FIG. 8C. In spite of being focused on, the subject B is blurred. In such a case, if the presence / absence of the peak of the focus table value and the maximum value of the focus evaluation value are reset, the image is displayed sharply as indicated by 8c-2 in FIG. 8C. The user may perform manual focusing operation from the reset state. In this embodiment, the release button 2 is half-pressed and released to reset the presence / absence of the focus table value peak and the maximum focus evaluation value, but other operations may be used (operation It is not an embodiment to limit). However, it is desirable that the operation be relatively easy as in this case.

  Next, FIG. 9 will be described. FIG. 9A shows the relationship between the camera and the two subjects A and B. The subject A and the subject B having different distances are included in the field of view of the camera, and the subject A is closer to the camera than the subject B. Furthermore, it is assumed that two subjects overlap each other in the focus evaluation value acquisition area. The graph in FIG. 9B shows the relationship between the focus evaluation value and the focus distance in the situation described above. It is assumed that the subject B is in focus when the focus distance is near 1 m, the subject A is in focus when the focus distance is near 10 cm, and the subject A is assumed to have lower contrast. In such a situation, when the subject B is focused in a state where the process shown in FIG. 5 is operated, the display is as 9c-1 in FIG. 9C. When the user moves the focus lens to a distance at which the subject A is in focus, the subject A is blurred and displayed even though the subject A is in focus as indicated by 9c-2 in FIG. 9C. It will be. In such a case, when the presence / absence of the peak of the focus table value and the maximum value of the focus evaluation value are reset, the subject A is displayed sharply as indicated by 9c-3 in FIG. 9C. The user may perform manual focusing operation from the reset state.

FIG. 10 shows an example of a screen on which the user sets the blurring amount (corresponding to claim 10).
FIG. 10A shows the initial state of the screen for checking and setting the blur amount. By performing a predetermined operation, the user can set a blurring amount by selecting one of “weak”, “medium”, and “strong” as shown in FIG. 10B. . In this embodiment, there are three options, but there may be more options. Further, in this embodiment, what kind of processing is used for the blurring processing is not limited. However, when so-called Gaussian blurring is used, in Step S10 in FIG. `` Difference in focus evaluation value '' x `` Coefficient ''
The blurring amount shown in the figure corresponds to the “coefficient” of the above-described equation.

FIG. 11 shows an example of a screen on which the user sets the sensitivity of blurring processing shown in claim 8 (corresponding to claim 11).
FIG. 11A shows the initial state of the screen for checking and setting the blur sensitivity. By performing a predetermined operation, the user can set the blur sensitivity from three types of “insensitive”, “medium”, and “sensitive” as shown in FIG. In this embodiment, there are three options, but there may be more options. The blur sensitivity corresponds to the threshold value in step S09 in FIG.
FIG. 12 and FIG. 13 are two different examples of screens displaying warnings about errors in the operation direction (corresponding to claim 12).
FIG. 12 shows a warning screen when the manual focus operation is performed with the upper / strobe button and the lower / macro button of the operation button group 14 of FIG. At the same time as a warning, an appropriate operation guide is displayed.
FIG. 13A shows a camera having a ring member (focusing ring) for manual focusing operation around the lens barrel 7. When performing a focusing operation with such a ring-shaped member, a warning screen that also serves as an operation guide as shown in FIG. 13B may be displayed.

As described above, in the manual focusing mode, the focus can be easily confirmed with high accuracy and high speed, and the user can take a picture at a timing when he / she wants to take a picture. . In particular, it is possible to easily confirm the desired one focus while confirming the overall composition.
When the user makes a mistake in the operation direction of the focus lens, the blur amount is exaggerated, so that the user can quickly notice an operation error. Furthermore, since an error in the operation direction for moving the focus lens can be detected and the user can be warned of the correct operation, even a person unfamiliar with the manual focusing operation can easily enjoy shooting by manual focusing. It is also possible not to display a warning for a person who does not need a warning display.
When the focus of a desired location matches, that is, when the user intends to take a picture, since the process of exaggerating the blur of the through image is not performed, it is easy to grasp the finished image.
It is possible to set a threshold (blur sensitivity) and a blur amount for starting blur processing according to user preference.
Since the entire image is blurred by a desired one-point focus evaluation value, hardware that can perform a particularly high-speed process is unnecessary. The operability in manual focus can be improved with cost and power consumption that are not much different from those of existing imaging devices.

1 Sub liquid crystal display (sub LCD)
2 Release button 3 Mode switching dial 4 Optical viewfinder 5 Strobe light emitting unit 6 Remote control light receiving unit (remote control light receiving unit)
7 Lens unit 8 Autofocus display light emitting diode (AF display LED)
9 Strobe display light emitting diode (strobe display LED)
10 Liquid crystal display monitor (LCD monitor)
DESCRIPTION OF SYMBOLS 11 Wide angle side (WIDE) zoom button 12 Telephoto side (TELE) zoom button 13 Power switch 14 Operation button group 15 Memory card / battery storage part 101 Image pick-up element 102 Front end part 103 SDRAM (Synchronous dynamic random access memory)
104 Camera processor 107 RAM (Random access memory)
108 ROM (Read Only Memory)
109 Sub CPU (Sub central processing unit)
110 Operation Unit 111 Sub LCD Driver 113 Buzzer 114 Strobe Circuit 115 Audio Recording Unit 116 Audio Playback Unit 117 LCD Driver 118 Video Amplifier (Video Amplifier)
119 Video Connector 120 Internal Memory 121 Memory Card Slot 122 USB (Universal Serial Bus) Connector 123 Serial Interface Unit 130 Wired / Wireless Ethernet (Registered Trademark) Circuit 131 LAN Connector 7-1 Zoom Optical System 7-1a Zoom Lens System 7-1b Zoom motor 7-2 Focus optical system 7-2a Focus lens system 7-2b Focus motor 7-3 Aperture unit 7-3a Aperture 7-3b Aperture motor 7-4 Shutter unit 7-4a Shutter 7-4b Shutter motor 7-5 Motor driver 102-1 Correlated double sampling unit (CDS)
102-2 Automatic gain controller (AGC)
102-3 A / D (Analog-Digital) Converter 102-4 Timing Generator (TG)
104-1 First imaging signal processing block 104-2 Second imaging signal processing block 104-3 CPU (central processing unit) block 104-4 Local SRAM (local static random access memory)
104-5 USB processing block 104-6 Serial processing block 104-7 JPEG codec (CODEC) block 104-8 Resize block 104-9 Video signal display block 104-10 Memory card controller block 115-1 Audio recording circuit 115 -2 Microphone amplifier 115-3 Microphone (microphone)
116-1 Audio reproduction circuit 116-2 Audio amplifier (audio amplifier)
116-3 Speaker 123-1 Serial Driver Circuit 123-2 Serial Connector

JP 2007-96753 A JP 2006-301080 A

Claims (13)

An imaging lens that includes a focus lens for focusing adjustment, and that forms a subject optical image;
Imaging means for acquiring a subject image by converting an optical image of the subject formed by the imaging lens into image data by an imaging element;
Through image display means for displaying the subject image acquired by the imaging means on a monitor in real time as a through image;
Manual focusing means for driving the focus lens of the imaging lens according to a manual operation;
Focusing evaluation information acquisition means for acquiring a focusing evaluation value from a predetermined position in the subject image;
Peak detection means for detecting the peak of the focus evaluation value acquired by the focus evaluation information acquisition means;
When the peak of the focus evaluation value is detected by the peak detection unit during manual operation of the focus lens by the manual focusing unit, the maximum value of the focus evaluation value and the latest of the focus evaluation value If the magnitude of the difference between the two exceeds a predetermined value, the through image is exaggerated by an amount corresponding to the magnitude of the difference, and the through image is displayed. A blur exaggeration display processing unit that exaggerates the blur of the through image by a predetermined amount and displays the through image when the peak of the focus evaluation value is not detected by the peak detection unit. An imaging device that is characterized.   The imaging apparatus according to claim 1, wherein the blur exaggeration display processing unit is a unit that changes a blur exaggeration amount of the through image in proportion to the difference in the focus evaluation value.   The blur exaggerated display processing means is means for exaggerating blur of the through image by Gaussian blur processing and changing a coefficient of the blur exaggeration amount in proportion to the difference of the focus evaluation values. The imaging device according to claim 2.   The blur exaggeration display processing means is means for exaggerating blur of the through image by blurring processing for suppressing high frequency components and changing the threshold frequency to be suppressed in proportion to the difference of the focus evaluation values. The imaging apparatus according to claim 2.   The image pickup apparatus according to claim 1, wherein the blur exaggerated display processing unit is implemented as a processing circuit made of hardware.   It further comprises means for superimposing and displaying the focus evaluation value acquisition position on the display screen of the through image, and means for easily changing the focus evaluation value acquisition position to an arbitrary position. The imaging device according to any one of claims 1 to 5.   When the blur exaggerated display processing unit starts the blur exaggerated display processing and when a predetermined operation is performed during the blur exaggerated display processing, the presence or absence of the peak of the focus evaluation value in the peak detecting unit and the alignment The imaging apparatus according to claim 1, further comprising reset processing means for resetting the maximum value of the focus evaluation value.   The reset processing means finely drives the focus lens for a predetermined range in the vicinity of the focus position at that time, whether there is a peak of the focus evaluation value within the predetermined range, and the maximum of the focus evaluation value within the predetermined range The imaging apparatus according to claim 7, wherein the imaging apparatus is means for determining a value.   9. The imaging apparatus according to claim 1, further comprising means for selecting whether to perform blur exaggerated display processing by the blur exaggerated display processing means by a user operation.   A plurality of patterns corresponding to differences in the strength of blur exaggeration are prepared in advance for the magnitude of the blur exaggeration amount in the blur exaggeration display processing by the blur exaggeration display processing means, and from these plural patterns, a user operation The imaging apparatus according to claim 1, further comprising means for selecting.   The sensitivity of the blur exaggerated display process corresponding to the difference between the maximum value of the focus evaluation value and the latest value at which the blur exaggerated display process is to be started in the blur exaggerated display process by the blur exaggerated display processing means is a plurality of stages. The imaging apparatus according to any one of claims 1 to 10, further comprising means for preparing values in advance and selecting from a plurality of stages by a user operation.   During manual operation of the focus lens by the manual focusing means, the user's operation direction is determined from the change in the focus evaluation value acquired by the focus evaluation information acquisition means, and the focus evaluation value is reduced. The operation direction warning means for generating a warning that the operation direction is not appropriate at the time of operation, and means for selecting whether or not to perform the operation direction warning by a user operation are further included. The imaging device according to any one of 11. Based on the focus evaluation value acquired from the predetermined position in the subject image by the focus evaluation information acquisition means and the focus evaluation value acquired by the focus evaluation information acquisition means, the peak detection means detects the focus evaluation information. Automatic focusing means for driving and controlling the focus lens to focus on the subject using the peak position of the focusing evaluation value.
The system according to any one of claims 1 to 12, further comprising means for selecting one of focusing by the manual focusing means and automatic focusing by the automatic focusing means by a user operation. The imaging device described.

Images