JP2011234083A - Imaging apparatus and control method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a photographer to confirm a whole composition and an enlarged image in an appropriate timing before taking a picture.SOLUTION: An imaging apparatus, during a live view shooting mode for displaying an object image at real time, makes an image display section display an enlarged image by an operation of an enlargement command button (S007). After performing a focus control on a focus area by operating an AF command button in this state, when a photographer operates an enlargement release command button (S011), a standard magnification image is displayed (S013), thereby enabling the photographer to take a picture after confirming its composition. A shutter button is a two-step composition, and the enlargement release command button is assigned to a first switch SW1 of the shutter button in the live view shooting mode.

Description

  The present invention relates to an imaging apparatus capable of confirming an overall composition and an enlarged image at appropriate timing, and a control method thereof.

  In portable electronic devices such as digital cameras that have an imaging function, light from a subject is collected by a photographic lens and imaged on an imaging device such as a CCD, image data is stored on a recording medium, and recorded image data is reproduced. Display on the image display. Some digital cameras have a so-called live view shooting mode in which a subject image is displayed on an image display unit in real time. The photographer can shoot a digital camera without an optical viewfinder while checking the composition using the image display unit. At this time, the photographer can enlarge the image in the display frame set in advance and check whether the subject is in focus or not while viewing the display image.

  Conventionally, when an enlargement instruction button is pressed during a live view shooting mode, a process for automatically selecting and enlarging a portion corresponding to a focus position is known (see Patent Document 1). In addition, a process is known in which when a photographer presses the shutter button of a digital camera halfway, an image in a display frame preset by the photographer is enlarged and displayed in an enlarged display area (see Patent Document 2).

JP 2003-179798 A JP-A-11-196301

In the conventional technique, there are the following problems regarding composition confirmation before photographing and confirmation of the entire composition and an enlarged image.
In the apparatus disclosed in Patent Document 1, when the photographer presses the enlargement instruction button in the live view shooting mode and presses the shutter button in a state where the image on the image display unit is enlarged, a standard review is performed in a quick review after shooting. An image with a magnification is displayed. For this reason, there is a problem that alignment is not possible before and after photographing, and the photographer cannot easily confirm the composition before photographing.

  In the apparatus disclosed in Patent Document 2, the photographer can confirm the composition before photographing by pressing the enlargement release instruction button while half-pressing the shutter button. However, in order to display the enlarged image again, the photographer once releases the half-pressed state of the shutter button and then needs to press the shutter button halfway again, so that much effort is required. In addition, since the enlargement release instruction button is provided exclusively, there is a problem that the number of operation members increases and installation space is required. Another problem is that the autofocus must be driven at the same time as displaying an enlarged image by half-pressing the shutter button.

  Accordingly, an object of the present invention is to enable a photographer to confirm the entire composition and an enlarged image at an appropriate timing when confirming the composition before photographing.

  In order to solve the above problems, an apparatus according to the present invention is an imaging apparatus having a mode for displaying a subject image on an image display unit in real time, and an image in an area set on a display screen of the image display unit. An enlargement instruction unit for enlarging and displaying, an AF instruction unit for instructing autofocus, an enlargement release instruction unit for releasing the enlargement of the image, and a control unit for controlling the photographing operation. The control means enlarges the image in the area when receiving an instruction from the enlargement instruction means during the mode, and when receiving an instruction from the AF instruction means, the enlarged image is displayed in the image display unit. When an instruction of the enlargement canceling instruction unit is received in a state where the image in the area is enlarged and displayed while the image is displayed, the image is returned to the magnification before enlargement and the image is Control to display on the image display unit.

  According to the present invention, the photographer can confirm the overall composition and the enlarged image at an appropriate timing.

FIG. 6 is a schematic cross-sectional view showing an application example to a digital camera in order to describe the embodiment according to the present invention in conjunction with FIGS. It is a rear perspective view of a digital camera. It is a block diagram which shows the structural example of a digital camera. It is a flowchart which shows the operation example of a digital camera. It is a figure which shows the example of a display of an image display part.

  FIG. 1 is a longitudinal sectional view showing an example of an embodiment in which the present invention is applied to a digital camera 10. FIG. 1A shows the camera state in the normal photographing mode, and the optical path is indicated by a one-dot chain line. The photographing lens 11 collects light from the subject, and the light reflected by the mirror 12 is guided to the optical finder 14 by the pentaprism 13. The photographer looks into the optical viewfinder 14 and shoots while confirming the composition. The photographing operation is started by pressing the shutter button, the mirror 12 is retracted to the outside of the optical axis and the electronic curtain 15 is opened at the same time, and the light from the subject is imaged on the image sensor 16 and image data is recorded on a recording medium described later. Is saved. FIG. 1B shows a camera state in the live view shooting mode. In the live view shooting mode, the mirror 12 is retracted to a position off the optical axis, and the electronic curtain 15 is kept open. As indicated by the one-dot chain line, the light from the subject reaches the image sensor 16 and the element always converts the light into an electric signal, so that an image can be displayed in real time. The photographer can confirm the subject image by continuously displaying the image in real time even in the digital camera 10 that does not include the optical viewfinder 14.

  FIG. 2 is a schematic perspective view of the digital camera 10 as viewed from the back. The image display unit 24 displays images and various types of information, and is used for real-time display in live view shooting mode and for reproducing and displaying images after shooting.

  Hereinafter, each operation button will be briefly described. A power button 64 located on the left side of the image display unit 24 is a button for instructing to turn on (turn on) / off (cut off) the power of the camera body. The image playback button 58 thereabove is a button for reading data stored in an image display memory described later and instructing the image display unit 24 to display an image. The live view button 53 further above is a button for instructing the start of the live view shooting mode, and the photographer can switch between the normal shooting mode and the live view shooting mode by pressing the button.

  A shutter button 50 provided on the upper surface of the camera housing is a shutter member (shutter release operation member) having a two-stage switch configuration, and is operated during shooting or live view shooting mode. In the normal shooting mode, when the shutter button 50 is half-pressed, the first switch (hereinafter referred to as SW1) is turned on, and an instruction for a shooting preparation operation is performed. When the photographer further depresses the shutter button 50, the second switch (referred to as SW2) is turned on, and an instruction to start the photographing operation is given. In the live view shooting mode, SW1 functions as an enlargement cancellation instruction button, and SW2 instructs the system control circuit described later to start the shooting operation.

  An AF instruction button 54 located on the right side of the image display unit 24 is a button for instructing AF (autofocus) control, and can be used by the photographer in both the normal shooting mode and the live view shooting mode. The display frame movement button 56 below the operation button is an operation unit for moving a display frame described later on the display screen of the image display unit 24 during the live view shooting mode. In this example, the operation instruction means for moving the display frame can be moved in four directions, up, down, left, and right. However, the present invention is not limited to this, and other instruction means and selection means such as an eight-direction movement operation means and a touch panel may be used. You may use. The enlargement instruction button 55 to the right of the AF instruction button 54 is a button for instructing enlargement of the image in the display frame that has been moved by the display frame movement button 56 in the live view shooting mode.

  FIG. 3 is a block diagram illustrating a configuration example of the digital camera 10. Light from the subject forms an image on the image sensor 16 via the photographing lens 11 and is converted into an electric signal. An electronic curtain 15 that adjusts the amount of light guided to the image sensor 16 is provided in front of the image sensor 16. The A / D converter 20 converts the analog output signal of the image sensor 16 into a digital signal. The image processing circuit 22 performs predetermined pixel interpolation processing and color conversion processing on the data from the A / D converter 20 or the data from the memory control circuit 23. The image processing circuit 22 performs predetermined calculation processing using the captured image data, and sends the obtained calculation result to the system control circuit 40, thereby performing AF processing, AE (automatic exposure) processing, AWB (auto white balance). ) Processing is performed.

  The memory control circuit 23 controls the A / D converter 20, the image processing circuit 22, the image display memory 32, the D / A converter 21, the memory 30, and the enlargement magnification storage circuit 31. Data from the A / D converter 20 is written into the image display memory 32 or the memory 30 via the image processing circuit 22 and the memory control circuit 23, or is stored into the image display memory 32 or the memory 30 via the memory control circuit 23. Written.

  A display device (TFT / LCD or the like) is used for the image display unit 24, and the display image data written in the image display memory 32 is output to the image display unit 24 via the D / A converter 21. An image is displayed. The memory 30 stores captured still image and moving image data, and has a storage capacity sufficient to store a predetermined number of still image data and a predetermined amount of moving image data. Thus, the digital camera 10 can write a large amount of image data to the memory 30 at high speed even in continuous shooting or panoramic shooting in which a plurality of still images are continuously shot.

  The exposure control unit 34 controls the electronic curtain 15 having a diaphragm function, and the focus adjustment control unit 35 controls the focusing of the photographing lens 11. In this example, a TTL (Through The Lens) method is employed, and the system control circuit 40 performs the exposure control unit 34 and the focus adjustment control unit 35 on the basis of the calculation result obtained by calculating the captured image data by the image processing circuit 22. Issue a control command.

  The system control circuit 40 controls the entire digital camera 10. An arithmetic processing unit such as a CPU constituting the system control circuit 40 realizes each process described below by interpreting and executing a program stored in the nonvolatile memory 41. The display unit 42 presents an operation state, a message, and the like by outputting characters or images together with sound according to a program executed by the system control circuit 40. The display unit 42 also displays a display frame during live view (see reference numeral 43 in FIGS. 2 and 5A).

  The aforementioned operation buttons or operation units indicated by reference numerals 50, 53 to 56, and 58 and the quick review switch 57 are operation instruction means for instructing the system control circuit 40 to perform various operations. I do.

  The first switch SW1 of the shutter button 50 is turned on when the shutter button 50 is half-pressed, and instructs the system control circuit 40 to start operations such as AF processing, AE processing, and AWB processing. The second switch SW2 is turned on when the shutter button 50 is fully pressed. As a result, the system control circuit 40 is instructed to start the exposure process in which the pixel signal read from the image sensor 16 is written as image data in the memory 30 via the A / D converter 20 and the memory control circuit 23. At the same time, the start of a series of processing such as development processing and subsequent image recording is instructed. The development processing is performed by calculation in the image processing circuit 22 and the memory control circuit 23, and the image recording processing reads image data from the memory 30, compresses it by the compression / decompression circuit 33, and stores the image on a recording medium 80 described later. This is done by writing data.

  The live view button 53 sends a signal for switching between the normal shooting mode and the live view shooting mode to the system control circuit 40. The AF instruction button 54 sends an instruction signal for starting operations such as AF processing, AE processing, and AWB processing to the system control circuit 40. The AF instruction button 54 can be used in both the normal shooting mode and the live view shooting mode, and issues an instruction according to the mode to the system control circuit 40.

  The enlargement instruction button 55 sends an instruction signal for enlarging the area of the display frame 43 shown in FIGS. 2 and 5A to the system control circuit 40. The function of the enlargement cancellation instruction button is assigned to the first switch SW1 of the shutter button 50 in the live view shooting mode. When SW1 is pressed in the live view shooting mode, the shooting preparation operation is not started, an enlargement magnification cancellation instruction is sent to the system control circuit 40, and the standard magnification control unit 44 is controlled to display an image at the standard magnification. To do.

  The display frame moving button 56 sends an instruction signal for moving the display frame on the screen of the image display unit 24 to the system control circuit 40 during the live view shooting mode. The quick review switch 57 is a quick review ON / OFF switch, and a photographer can operate the switch to set a quick review function for automatically reproducing image data taken immediately after shooting. The image playback button 58 reads the data stored in the image display memory 32 and sends an instruction signal for causing the image display unit 24 to display an image to the system control circuit 40. The power button 64 sends a signal for instructing to turn on or off the power of the camera body to the system control circuit 40.

  The power supply control unit 60 detects the presence / absence of a battery, the type of battery, the remaining battery level, and the like, and includes the recording medium 80 for a necessary voltage for a necessary period based on the detection result and an instruction from the system control circuit 40. Supply to each part. A primary battery or a secondary battery, an AC adapter, or the like is used for the power supply 63 connected to the power supply control unit 60 via the connectors 61 and 62.

The interface unit 70 mediates transmission / reception of information performed between the recording medium 80 such as a memory card or a hard disk and the digital camera 10. A recording medium 80 is connected to the connector 71. The recording medium attachment / detachment detection unit 74 detects whether or not the recording medium 80 is attached to the connector 71 and notifies the system control circuit 40 of it. Note that the number of interfaces and connectors to which the recording medium 80 is attached is not limited to one system, and a configuration in which the number of systems is further increased may be used, or a configuration in which interface units and connectors having different standards are combined. Furthermore, by connecting various communication cards to the connector 71, image data and management information accompanying the image data can be transferred to and from other devices.
The recording medium 80 includes a recording unit 75 constituted by a semiconductor memory, a magnetic disk, or the like, an interface unit 72 with the digital camera 10, and a connector 73 connected to the digital camera 10.

  Next, the operation of the digital camera 10 will be described using the flowchart of FIG. When the live view button 53 is pressed in S001, the system control circuit 40 sets the mode to the live view shooting mode. In this mode, the mirror 12 is retracted to a position off the optical axis, the electronic curtain 15 is kept open, and the image sensor 16 always converts light into an electrical signal, so that an image is displayed on the image display unit 24 in real time. Is displayed. In S002, a count variable (denoted as i) for counting how many times the enlargement instruction button 55 is pressed is initialized, and an initial value zero is set as the i value. In S003, the system control circuit 40 determines whether or not there is an instruction to move the display frame 43. When it is determined that there is an instruction to move the display frame 43, the process proceeds to S004, and after the display frame 43 has moved, the process returns to S003. If there is no instruction to move the display frame 43, the process proceeds to S005.

  In S005, the system control circuit 40 determines whether or not the enlargement instruction button 55 has been pressed. If the enlargement instruction button 55 is not pressed, the process proceeds to S008, and if the enlargement instruction button 55 is pressed, the process proceeds to S006. In S006, an increment process related to the number of operations of the enlargement instruction button 55 is performed, and the value of the count variable i is incremented by 1 (i = i + 1). In the next S007, the system control circuit 40 controls the image to be enlarged by increasing the enlargement magnification by one step. In S008, the system control circuit 40 determines the operation of the AF instruction button 54. If the AF instruction button 54 is pressed, the process proceeds to S009. If the button is not pressed, the process proceeds to S010.

  In step S009, the system control circuit 40 starts AF driving and instructs each unit to start photographing preparation operations such as AE processing and AWB processing. S010 is a process for determining whether or not the enlargement instruction button 55 has been pressed. If the enlargement instruction button 55 has not been pressed, the process proceeds to S011, and if the enlargement instruction button 55 has been pressed, the process returns to S006. In this example, a mode in which the enlargement magnification can be set in a plurality of stages will be described.

  In S011, the system control circuit 40 determines whether or not SW1 is turned on by operating the shutter button 50. When SW1 is in the off state, the process returns to S008, and when SW1 is in the on state, the process proceeds to S012.

  In S012, the system control circuit 40 calculates an enlargement magnification when SW1 is turned on by operating the shutter button 50. Here, a method of calculating how many times the enlargement instruction button 55 has been pressed until the time point of S012 will be described. For example, when the enlargement instruction button 55 is pressed once for the standard magnification image displayed on the image display unit 24, the area in the display frame 43 shown in FIG. The image is enlarged and displayed twice. When the enlargement instruction button 55 is pressed twice, the area of the display frame 43 is enlarged 10 times compared to the standard magnification image, and when the enlargement instruction button 55 is pressed three times, the display returns to the standard magnification image. Thereafter, assuming a program process in which the same operation is repeated, the number of times the enlargement instruction button 55 is pressed is represented by the count variable i, so that the natural number variable is n (= 1, 2, 3,...). In this case, the magnification is as follows.

-When i = 3n-3, enlargement magnification 1 (standard magnification image).
When i = 3n−2, enlargement magnification is 5 (5 times enlargement image).
When i = 3n−1, the magnification is 10 (10 times magnified image).

The system control circuit 40 obtains the enlargement magnification by arithmetic processing, and stores the enlargement magnification data in the enlargement magnification storage circuit 31.
In S013, the system control circuit 40 returns the image displayed by the image display unit 24 to the image at the magnification before enlargement, in this example, the standard magnification image. Thereby, the photographer can confirm the composition by displaying on the image display unit 24 before photographing. In next step S014, the system control circuit 40 determines whether or not SW2 is turned on by operating the shutter button 50. If SW2 is on, the process proceeds to S016. If SW2 is off, the process proceeds to S015.

  In step S016, the system control circuit 40 instructs each unit to start shooting operation, and executes shooting processing. In S017, the captured image is displayed on the image display unit 24 as a quick review. When the image display unit 24 displays the photographed image by the quick review, the photographer can confirm the composition and confirm that there is no focus shift. Then, the process proceeds to S018.

  In S015, the system control circuit 40 determines whether or not SW1 is kept on. If SW1 remains in the on state, the process returns to S014 to continue monitoring the state of SW2. On the other hand, when SW1 is turned off by releasing the shutter button 50, the process proceeds to S018. Here, the system control circuit 40 reads data indicating the enlargement magnification stored in the enlargement magnification storage circuit 31 in S012. Thereafter, the process proceeds to S019, and the image display unit 24 displays the enlargement magnification based on the read data indicating the enlargement magnification, and then returns to S008. This operation is meaningful when, for example, the photographer accidentally touches a focus ring (not shown) before starting shooting by turning on SW2 in a situation where S019 is reached from S015 through S018. . When the photographer's finger moves away from the shutter button 50 and SW1 is turned off, an enlarged image is displayed on the image display unit 24, so that the photographer can easily focus. Further, in the situation where the process reaches S019 from S017 through S018, the image display unit 24 displays a magnification image at the time of shooting after shooting. For this reason, when the photographer wants to take a picture only by checking whether or not the same composition is in focus, it is not necessary to press the enlargement instruction button 55 every time the picture is taken, and the process returns from S019 to S008.

  FIG. 5 shows a display example of the image display unit 24 when the photographer instructs the system control circuit 40 with various buttons according to the processing shown in the flowchart of FIG. First, during the live view shooting mode, the photographer performs an operation of moving the display frame 43 to a portion to be focused. This is performed by the photographer instructing the system control circuit 40 in a desired direction using the display frame moving button 56, and the display frame 43 displayed on the image display unit 24 is moved in accordance with the operation instruction ( (See FIG. 5 (a)). Next, the photographer operates the enlargement instruction button 55 to confirm whether or not the focus is in the vicinity of the focus area, and enlarges the image in the area of the display frame 43 (see FIG. 5B). . The photographer can focus by AF driving while the enlarged screen is displayed by operating the AF instruction button 54 even while the image display unit 24 performs the image enlargement display process. When the focus setting is selected not to AF but to MF (manual focus), it is possible to focus by manual operation using a focus ring (not shown). In either case, the focused enlarged image is displayed on the image display unit 24 (see FIG. 5C).

  When the shutter button 50 is pressed during the normal shooting mode and the SW1 is turned on, the operation means an instruction to start the shooting preparation operation, but an instruction to start the shooting preparation operation is performed in the live view shooting mode. This means another operation instruction. That is, the enlargement display process for the image being enlarged displayed on the image display unit 24 is canceled, and the image is displayed at the standard magnification (see FIG. 5D). Thus, the photographer can start photographing after confirming the composition before photographing by turning on SW1. In the live view shooting mode, when the AF instruction button 54 is operated instead of the SW1 of the shutter button 50, the system control circuit 40 receives an instruction to start the shooting preparation operation. In this state, when the shutter button 50 is further operated and the SW2 is turned on, the system control circuit 40 starts the photographing operation (see FIG. 5E). In the state of FIG. 5D, when the photographer's finger leaves the shutter button 50 and SW1 is turned off, the system control circuit 40 stores the magnification data when SW1 is turned on. Read from circuit 31. The image display unit 24 displays the image at the magnification (see FIG. 5C). With this operation, even if the photographer accidentally touches the focus ring during composition confirmation, the enlarged image is displayed on the image display unit 24 by turning off SW1, so that the in-focus state is reconfirmed. Easy to do.

  According to the present embodiment, when an enlarged image is displayed in the live view shooting mode, after the focus area is focused by the AF instruction button 54, the standard magnification image is displayed by the enlargement cancellation instruction button. The photographer can start shooting after confirming the composition. Since this enlargement release instruction button is assigned to the first switch SW1 of the shutter button 50, an operation member dedicated to enlargement release is unnecessary and contributes to cost reduction. The photographer can confirm the composition before photographing with a series of operation sensations, and can obtain the effect that the entire composition and the enlarged image can be confirmed at an appropriate timing.

DESCRIPTION OF SYMBOLS 10 Digital camera 24 Image display part 31 Magnification magnification memory circuit 40 System control circuit 50 Shutter button SW1 1st switch SW2 2nd switch 53 Live view button 54 AF instruction button 55 Magnification instruction button

Claims (5)

An imaging apparatus having a mode for displaying a subject image on an image display unit in real time,
An enlargement instruction means for enlarging and displaying an image in an area set on the display screen of the image display unit;
AF instruction means for instructing autofocus;
An enlargement cancellation instruction means for canceling the enlargement of the image;
Comprising control means for controlling the photographing operation;
The control means enlarges the image in the area when receiving an instruction from the enlargement instruction means during the mode, and when receiving an instruction from the AF instruction means, the enlarged image is displayed in the image display unit. When an instruction of the enlargement canceling instruction unit is received in a state where the image in the area is enlarged and displayed while the image is displayed, the image is returned to the magnification before enlargement and the image is An image pickup apparatus that is controlled to be displayed on an image display unit. Further comprising an enlargement magnification storage means for storing enlargement magnification data relating to the image in the region;
The control means stores, in the enlargement magnification storage means, enlargement magnification data obtained by enlarging an image in the area in response to an instruction from the enlargement instruction means during the mode, and the enlargement release instruction means 2. The imaging apparatus according to claim 1, wherein when the operation is released, the magnification data is read out from the magnification storage means and the magnification is displayed on the image display unit. Further comprising an enlargement magnification storage means for storing enlargement magnification data relating to the image in the region;
The control means stores the magnification data when the image in the area is magnified in response to an instruction from the magnification instruction means during the mode in the magnification magnification storage means, and photographing is performed. 2. The imaging apparatus according to claim 1, wherein after the photographed image is reproduced on the image display unit, the magnification data is read from the magnification storage unit, and the magnification is displayed on the image display unit. . A shutter member having a first switch and a second switch;
When the first switch is operated during shooting, the control means receives the operation instruction as an instruction for shooting preparation operation, and when the first switch is operated as the enlargement release instruction means during the mode, The operation instruction is accepted as an instruction to cancel the enlargement of the image, and when the second switch is operated, an instruction to start a photographing operation is accepted. Imaging device. A method for controlling an imaging apparatus having a mode for displaying a subject image on an image display unit in real time,
From an enlargement instruction means for enlarging and displaying an image in an area set on the display screen of the image display section, an AF instruction means for instructing autofocus, and an enlargement release instruction means for releasing the enlargement of the image Receiving instructions,
When receiving an instruction from the enlargement instruction unit during the mode, the image in the area is enlarged. When receiving an instruction from the AF instruction unit, the enlarged image is displayed on the image display unit. A step of performing a shooting preparation operation in between,
A step of displaying the image on the image display unit by returning to a magnification before enlargement when receiving an instruction from the enlargement cancellation instruction means in a state where the image in the area is enlarged and displayed. A control method for an imaging apparatus.

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