JP2005217898A - Imaging device and imaging method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To offer an imaging device and an imaging method which can easily confirm a saturation region in a photographing image, and can easily control formation of the saturation region according to user's preference. <P>SOLUTION: An imaging device 100 specifies pixels which become a saturation condition from image data showing a photographed image, and displays the pixels which become the saturation condition so as to be able to distinguish from other image region. Furthermore, if there are pixels which become the saturation condition, the device reports it to a user by characters or voice, and reports that it is urged to perform setting change of imaging conditions to the user by characters and voice. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an imaging apparatus such as a digital camera that captures a subject and creates image data, and an imaging method.

Image data created by a digital still camera (hereinafter referred to as a digital camera) is displayed on a CRT monitor or output as a print. However, unlike a negative film, a digital camera has a very narrow dynamic range, and whether or not it was shot properly depends greatly on how well exposure control was performed according to various shooting scenes. Dependent.
On the other hand, when a negative film shot in a shooting scene with a large luminance difference is developed and printed on photographic paper, the bright areas are uniformly white areas (white areas) and the dark areas are uniformly black areas. In some cases, black areas are formed. In order to suppress such formation of overexposure and underexposure, a technique such as “covering” or “burning” is used. This dodging or burning (hereinafter collectively referred to as dodging) is, for example, when creating a photographic print from a negative film, giving normal exposure to an intermediate density area, Select a long-time exposure using a perforated shielding plate for the area where the image is likely to be formed, and selectively use a shielding plate for the area where the black crush is likely to be formed on the photo print. This is a technique for shortening the exposure time. As a result, it is possible to obtain a photographic print that maintains the contrast and gradation of each subject and does not cause overexposure or underexposure (that is, no saturation occurs in bright and dark areas).
The dodging technique described above is possible because the negative film itself has a wide dynamic range and can record a subject with a large luminance difference as information, and can be applied to a digital camera with a narrow dynamic range. It is difficult.
For this reason, in a digital camera, the signal value acquired by the image sensor is a value that can be sensed by the image sensor, for example, by performing exposure control by adjusting the shutter speed and aperture so that the above-described whiteout is not formed. The shooting conditions are controlled so as not to exceed the maximum value (that is, not to saturate with respect to the dynamic range of the digital camera) to avoid overexposure. Further, a technique has been devised in which an exposure level is estimated from the area of a region saturated in a bright part and a dark part, and correction processing is performed based on the estimated exposure level (see Patent Document 1). Hereinafter, a state where the signal value acquired by the image sensor is equal to or greater than the maximum value may be expressed as “saturation”.
JP-A-11-195115

However, since the actual shooting scene has a very wide luminance range, and the range of the luminance range that can be taken by the image sensor is limited, the overexposure can be achieved only by performing exposure control based on a predetermined algorithm (that is, automatic exposure control). It is difficult to avoid this sufficiently.
The technique described in Patent Document 1 is based on the premise that the captured image itself includes a saturated image region. However, since the information on the subject is missing in the saturated image area, the missing information is not compensated even if correction processing is performed, and it is difficult to obtain a high-quality output image.

  An object of the present invention is to provide an imaging apparatus and an imaging method in which a saturated region formed in a captured image can be easily confirmed, and the formation of the saturated region can be easily controlled according to a user's preference.

In order to solve the above problem, the invention according to claim 1
In an imaging device that displays an image signal acquired on the basis of imaging conditions set in advance via an imaging element on a display unit,
A control unit is provided that identifies a pixel having a maximum signal value (ie, is saturated) with respect to the acquired image signal, and controls to display the identified pixel on the display unit. And

Further, as in the invention according to claim 2, in the invention according to claim 1,
The controller is
It is preferable to perform control so that the identified pixel is highlighted so as to be distinguishable from other pixels among the pixels of the image signal.

Further, in the invention according to claim 1 or 2, as in the invention according to claim 3,
The controller is
It is preferable to determine whether or not there is a pixel having a maximum signal value with respect to the acquired image signal, and control to notify the determination result.

Further, as in the invention according to claim 4, in the invention according to any one of claims 1 to 3,
The controller is
When there is a pixel having a maximum signal value with respect to the acquired image signal, it is preferable to perform control so as to notify that the setting of the photographing condition is to be changed.

Further, as in the invention described in claim 5, in the invention described in any one of claims 1 to 4, the display unit is configured integrally with the apparatus main body (that is, the imaging apparatus main body). May have been
As in the invention described in claim 6, in the invention described in any one of claims 1 to 4, the display unit is provided separately from the apparatus main body (that is, the imaging apparatus main body). It may be.

Moreover, in order to solve the said subject, invention of Claim 7 is the following.
In an imaging method for displaying an image signal acquired on the basis of imaging conditions set in advance via an imaging element on a display unit,
A pixel having a maximum signal value is specified for the acquired image signal, and the specified pixel is displayed on the display unit.

Furthermore, as in the invention according to claim 8, in the invention according to claim 7,
It is preferable that the identified pixel is highlighted so as to be distinguishable from other pixels among the pixels of the image signal.

Further, in the invention according to claim 7 or 8, as in the invention according to claim 9,
It is preferable to determine the presence or absence of a pixel having a maximum signal value for the acquired image signal and to notify the determination result.

Further, as in the invention according to claim 10, in the invention according to any one of claims 7 to 9,
When there is a pixel having a maximum signal value with respect to the acquired image signal, it is preferable to notify that the setting of the photographing condition is to be changed.

  According to the present invention, even when there are pixels in a saturated state, the shooting conditions such as exposure control are not automatically changed, and the shooting conditions such as exposure desired by the user can be finely changed. Therefore, an imaging device having high convenience and functionality and capable of obtaining a high-quality captured image can be realized. Furthermore, since the user can change the shooting conditions such as exposure by himself and create and save a captured image desired by the user, an intention that may occur when the shooting conditions such as exposure control are automatically changed. Occurrence of missing image information or the like can be avoided.

  The present embodiment will be described with reference to the drawings. First, the configuration of the imaging apparatus 100 will be described.

  As illustrated in FIG. 1, the imaging apparatus 100 includes a lens unit 101, a CCD (Charge Coupled Device) 102 as an imaging element, a processor 103, a data storage unit 104, a control unit 105, a memory 106, an operation unit 107, and a display unit 108. Etc.

  The CCD 102 photoelectrically converts a captured image incident through the lens unit 101 into an electric signal, converts the electric signal into digital data, and outputs the digital data. The digital data conversion process may be performed using an A / D converter separate from the CCD 102.

  The processor 103 performs compression / decompression of image data input from the CCD 102 or the data storage unit 104.

  The data storage unit 104 is a readable / writable memory that stores image data input from the processor 103.

  The control unit 105 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like (all not shown). The CPU executes the various programs stored in the ROM and the memory 106, whereby the image pickup apparatus 100 is comprehensively controlled. The control unit 105 particularly performs the processing shown in the flowchart of FIG.

  The memory 106 stores various programs executed by the control unit 105 and various data necessary for executing the programs.

  The operation unit 107 includes various input keys (not shown), such as a release switch for inputting a shooting instruction. The operation unit 107 outputs various instruction inputs for performing operation control of the imaging apparatus 100 to the control unit 105 in response to pressing of these various input keys.

  The display unit 108 includes a display device (sometimes referred to as an electronic viewfinder) such as an LCD (Liquid Crystal Display) (not shown), and displays various display data input from the control unit 105 on the display device. .

  Note that the imaging apparatus 100 preferably includes a speaker, and can output a message voice stored in a memory such as a ROM of the control unit 105 via the speaker.

  Next, imaging processing by the imaging apparatus 100 will be described with reference to FIG. The imaging process described here is realized by the control unit 105 executing a program.

  First, shooting conditions (for example, exposure conditions) are set via the operation unit 107 (step S1). When shooting is performed under the shooting conditions, image data is input via the CCD 102 and the processor 103. (Step S2). This image data is a signal value in which each RGB color is represented in a range from 0 to 255 for each pixel.

  After step S2, a pixel in the saturated state (a state in which any of RGB signal values takes a value of 255) is specified from the input image data (step S3). When the captured image represented by the image data is displayed on the display device of the display unit 108, only the pixels in the saturated state are displayed in a display format that can be distinguished from other image regions (step S4). ). As this display format, for example, a display format in which only saturated pixels are displayed in a specific color such as red or blinked in the specific color is possible. Further, for a pixel in a saturated state, it may be a display format in which the pixel is displayed in the same color regardless of whether one of RGB colors is saturated, or A display format may be used in which pixels in a saturated state are displayed in different colors so that it can be determined whether any of RGB colors is saturated.

  In this case, a message indicating that there is a pixel that is saturated (for example, “there is a pixel that is saturated”) is displayed on the display screen of the display unit 108, or is output to the user. Inform.

  After step S4, a selection input as to whether or not to save the image data currently displayed on the display screen of the display unit 108 in the data storage unit 104 is requested (step S5). At this time, it is preferable to display a message such as “Do you want to save this image?” On the display screen of the display unit 108.

  In the stage of step S5, when selection input indicating that the currently displayed image data is stored in the data storage unit 104 is OK (step S5; Yes), the processor 103 compresses the image data, The data is stored in the data storage unit 104 (step S8), and this process ends.

  If a selection input not to save the image data in the data storage unit 104 is made in step S5 (step S5; No), a message (for example, “ Please lower the exposure "or the like on the display screen of the display unit 108 or output the sound. Then, after the display, the shooting conditions are changed according to the change instruction input via the operation unit 107 (step S6), and the shooting is performed according to the re-shooting instruction input via the operation unit 107 (step S6). S7) Thereafter, the process proceeds to step S2, and the processes after step S2 are repeated.

  As described above, the imaging apparatus 100 identifies a pixel in a saturated state from image data representing a captured image, and displays the pixel in a saturated state so that it can be distinguished from other image regions. . Further, when there is a pixel in a saturated state, this is notified to the user by text or voice, and the user is also notified by text or voice of prompting the user to change the shooting condition setting.

  Therefore, even if there are pixels that are saturated, it is possible to finely change the shooting conditions such as exposure as desired by the user without automatically changing the shooting conditions such as exposure control. The imaging device 100 having convenience and functionality and capable of obtaining a high-quality captured image can be realized. Furthermore, since the user can change the shooting conditions such as exposure by himself and create and save a captured image desired by the user, an intention that may occur when the shooting conditions such as exposure control are automatically changed. Occurrence of missing image information or the like can be avoided.

  Note that the description in the present embodiment shows an example of an imaging apparatus and an imaging method according to the present invention, and the present invention is not limited to this. The detailed configuration and detailed operation of the imaging apparatus 100 according to the present embodiment can be changed as appropriate without departing from the spirit of the present invention.

  For example, the imaging apparatus 100 includes the display unit 108 integrally, but the configuration is not limited thereto, and the configuration may be such that the display unit 108 is a separate body. As such a display unit 108, for example, a display such as a PC (Personal Computer) can be used. In this case, the imaging apparatus 100 and the PC can be connected by a cable (or wireless communication).

It is a block diagram which shows the structure of the imaging device to which this invention is applied. It is a flowchart explaining the imaging process to which this invention is applied.

Explanation of symbols

100 Imaging device 101 Lens unit 102 CCD
103 processor 104 data storage unit 105 control unit 106 memory 107 operation unit 108 display unit

Claims (10)

In an imaging device that displays an image signal acquired on the basis of imaging conditions set in advance via an imaging element on a display unit,
An imaging apparatus comprising: a control unit configured to specify a pixel having a maximum signal value with respect to the acquired image signal and to display the specified pixel on the display unit. The controller is
The imaging apparatus according to claim 1, wherein the specified pixel is controlled to be highlighted so as to be distinguishable from other pixels among the pixels of the image signal. The controller is
The imaging apparatus according to claim 1, wherein control is performed so as to determine whether or not there is a pixel having a maximum signal value with respect to the acquired image signal and to notify the determination result. The controller is
4. The control unit according to claim 1, wherein when there is a pixel having a maximum signal value with respect to the acquired image signal, control is performed so as to notify that the setting of the shooting condition is to be changed. The imaging device according to one item.   The imaging apparatus according to claim 1, wherein the display unit is configured integrally with the apparatus main body.   The imaging apparatus according to claim 1, wherein the display unit is provided separately from the apparatus main body. In an imaging method for displaying an image signal acquired on the basis of imaging conditions set in advance via an imaging element on a display unit,
An imaging method comprising: identifying a pixel having a maximum signal value with respect to the acquired image signal, and displaying the identified pixel on the display unit.   The imaging method according to claim 7, wherein the identified pixel is highlighted so as to be distinguishable from other pixels among the pixels of the image signal.   The imaging method according to claim 7, wherein the presence or absence of a pixel having a maximum signal value is determined with respect to the acquired image signal, and the determination result is notified.   10. The system according to claim 7, wherein when there is a pixel having a maximum signal value with respect to the acquired image signal, notification that setting of the shooting condition is to be changed is provided. The imaging method described.

Images