KR101128518B1 - Imaging method for digital image processing device - Google Patents

Abstract

According to another aspect of the present invention, there is provided a method of photographing a digital image processing apparatus, the method including determining whether a backlight condition is applied; Storing a flash mode when it is determined that the backlighting condition is performed; Determining whether the light emitting mode is inhibited; Setting a forced light emission mode when the light emission prohibition mode is not included; Performing auto focusing and photographing; And reducing to a stored flash mode.

According to the photographing method of the digital image processing apparatus of the present invention, the photographing is performed by forced light emission under backlight conditions, so that the photographed image is brighter than the subject.

Description

Imaging method for digital image processing device}

1 is a block diagram illustrating a configuration of an exemplary digital camera to which the concept of the present invention can be applied.

2 is a flowchart illustrating a photographing method of a digital image processing apparatus according to an exemplary embodiment of the present invention.

3 illustrates an exemplary flash emission mode of a digital camera.

4 is a diagram illustrating an example of a rear surface of a digital camera as an example of a digital image processing apparatus to which the automatic focus adjustment method of the present invention may be applied.

5 is a preview image displayed on the LCD monitor of FIG.

6 shows a state in which the forced light emission mode is set by step S106.

FIG. 7 illustrates an image in which the subject part is brightly photographed in the forced light emission mode under the backlighting condition in step S108.

8 illustrates a multi-field metering window for determining backlight conditions.

9 illustrates a conversion operation of a flash mode when photographing under a backlight condition.

The present invention relates to a digital image processing apparatus such as a digital camera, and more particularly, to an image capturing method of a digital image processing apparatus.

Digital cameras with built-in flash allow users to select and set the flash firing conditions.

In digital camera photography, a back light condition refers to a case in which rays such as sunlight and lighting are shining toward the camera from the back of a subject.

In the case of photographing flash emission by automatic exposure adjustment, since the overall brightness is high under backlight conditions, the conventional digital camera does not perform flash emission. Therefore, there is a problem that the image of the subject photographed in the backlight condition is darkened.

An object of the present invention is to provide a photographing method of a digital image processing apparatus capable of photographing a subject as a bright image under backlight conditions.

According to another aspect of the present invention, there is provided a method of photographing a digital image processing apparatus, the method including determining whether a backlight condition is applied; Storing a flash mode when it is determined that the backlighting condition is performed; Determining whether the light emitting mode is inhibited; Setting a forced light emission mode when the light emission prohibition mode is not included; Performing auto focusing and photographing; And reducing to a stored flash mode.

In the photographing method of the digital image processing apparatus, the backlighting condition may be determined using multi-field metering information.

Hereinafter, the configuration and operation of the present invention will be described in detail with reference to the accompanying drawings. Like reference numerals in the drawings denote components that perform the same function.

1 is a block diagram illustrating a configuration of an exemplary digital camera to which the concept of the present invention can be applied.

The optical system OPS including the lens unit and the filter unit optically processes light from a subject. The lens unit in the optical system OPS includes a zoom lens, a focus lens, and a compensation lens.

A photoelectric conversion unit (OEC) of a charge coupled device (CCD) or a complementary metal-oxide-semiconductor (CMOS) converts light from an optical system (OPS) into an electrical analog signal. Here, the digital signal processor 7 controls the timing circuit 2 to control the operation of the photoelectric converter OEC and the analog-to-digital converter 1. The CDS-ADC (Correlation Double Sampler and Analog-to-Digital Converter) element 1 as an analog-to-digital converter processes the analog signal from the photoelectric converter (OEC), removes the high frequency noise, and adjusts the amplitude. (auto gain control, AGC) and then convert to a digital signal. The digital signal processor 7 processes the digital signal from the CDS-ADC element 1 to generate a digital image signal classified into luminance and chroma signals.

The DRAM (Dynamic Random Access Memory) 4 temporarily stores digital image signals and other temporary processing data from the digital signal processor 7.

The EEPROM (Electrically Erasable Programmable Read Only Memory) 5 stores algorithms and setting data necessary for the operation of the digital signal processor 7. The memory card of the user is attached to and detached from the memory card interface 6.

The digital image signal from the digital signal processor 7 is input to the LCD driver 14, whereby the image is displayed on the color LCD panel 17.

On the other hand, the digital image signal from the digital signal processor 7 can be transmitted by serial communication via the USB (Universal Serial Bus) connection 18 or the RS232C interface 8 and its connection 19, and the video filter ( 9) and through the video output unit 20 can be transmitted as a video signal.

The audio processor 13 outputs the audio signal from the microphone MIC to the digital signal processor 7 or the speaker SP, and outputs the audio signal from the digital signal processor 7 to the speaker SP.

The user input unit INP may include a shutter button, a mode selection button, a function selection button, a zoom button, a direction movement button, and the like. The user input unit INP is operated by the user to generate a command for performing each function according to the user's instruction.

The microcontroller 12 controls the lens driver 10, whereby the zoom motor M _Z , the focus motor M _F , and the aperture motor M _A are zoom lenses in the optical system OPS, The focus lens and the aperture are driven respectively. The light emitting unit LAMP driven by the microcontroller 12 may include a self-timer lamp, an auto-focus lamp, a flash standby lamp, and the like. On the other hand, the microcontroller 12 drives the flash 15 by controlling the operation of the flash controller 11 in accordance with the signal from the flash-light amount sensor 16.

The digital camera to which the present invention can be applied does not have to include all the components of FIG. 1, and those skilled in the art may delete some of the components, add another component, or modify some components according to the specification. I will understand.

2 is a flowchart illustrating a photographing method of a digital image processing apparatus according to an exemplary embodiment of the present invention.

It is determined whether the backlight condition (S100).

If it is determined that the backlight condition is stored (S102).

It is determined whether or not the light-emitting prohibition mode is used (S104).

If it is not in the light-emitting prohibition mode under backlight conditions, it is set to the forced light-emitting mode (S106). The backlight condition refers to a case in which a ray of light is shining toward the camera from the back of the subject. In the backlight condition, the luminance difference is large in the screen between the divided windows. Therefore, in the conventional digital camera, the photographing is performed in a backlighting condition without additional correction, and thus, the surroundings of the subject are very bright and the subject portion is darkened as shown in FIG. 5. FIG. 5 is a preview image displayed on the LCD monitor of FIG. 4, in which the AE control is performed at a low luminance while the background is very high in backlight. In the present invention, the subject portion is photographed brightly by being forced to emit light under backlight conditions.

Auto focus (AF) and photographing are performed (S108). In the flash inhibit mode, step S108 is performed without flash. However, if the light emission prohibition mode is not performed, step S108 is performed in the forced light emission mode regardless of the light emission mode.

Return to the stored flash mode (S110). The present invention is characterized in that the flash is forcibly operated only when it is determined that the backlight condition is determined. Otherwise, the present invention is reduced to the conventional flash mode.

3 illustrates an exemplary flash emission mode of a digital camera. Referring to FIG. 5, the flash light emitting mode of the digital camera includes, for example, an auto / red-eye reduction / slow synchro / fill-in / flash off mode, and the like. There is this.

In the digital camera, it is determined whether or not the flash is fired by the autoexposure adjustment algorithm except for forced flash and flash off mode among flash flash conditions.

The auto mode is a flash mode in which the flash automatically fires when the background luminance becomes darker than the reference luminance. In the red-eye reduction mode, preliminary light emission is performed to reduce the phenomenon in which the human eyes are photographed red. In slow synchro mode, when shooting in dark places such as in the evening, the shutter speed is slow and the flash fires to shoot the subject and background brightly.

Hereinafter, a method for determining backlight conditions performed in step S100 will be described in detail. In step S100, the backlighting condition may be determined using, for example, multi-part metering information.

In multi-part metering, each area of the screen divided into several parts can be individually metered, the average value can be calculated to adjust the exposure, and the exposure difference of each part can be examined and the exposure can be automatically adjusted.

The backlight condition refers to a case in which a ray of light is shining toward the camera from the back of the subject. In the backlight condition, the luminance difference is large in the screen between the divided windows.

The determination of such backlight conditions is performed by using a window used in AF and a window used in AE. That is, in determining the backlight condition, information on the total luminance is obtained using the full multi-segment window used in the AE, and luminance information on the subject is obtained using the center window used in the AF.

FIG. 8 illustrates a multi-sided metering window for determining backlight conditions, wherein five windows hatched at the center are used for AF.

In FIG. 8, the image grid is composed of 7 × 5 grids horizontally and vertically. Therefore, the luminance value of each divided window may be represented by K (1,1), K (1,2), ..., K (7,5).

Backlight condition determination method using the exemplary multi-splitting window of Figure 8 will be described by the following equations (1) to (3).

First, the overall luminance level can be expressed by, for example, Equation 1 below.

 The luminance level of the subject portion by the AF window may be expressed by, for example, Equation 2 below.

 In operation S100, when the following Equation 3 is satisfied using Equations 1 and 2, it may be determined as a backlight condition.

 Equation 3 means that it is determined that the backlighting condition is different if the difference between the exposure values of the five central windows of the subject portion and the other windows is a predetermined value, for example, 2EV or more.

4 is a diagram illustrating an example of a rear surface of a digital camera as an example of a digital image processing apparatus to which the automatic focus adjustment method of the present invention may be applied.

At the rear of the digital camera of Fig. 4, the viewfinder 100, autofocus lamp 101, flash status lamp 102, mode dial 103, wide-angle zoom button 104, telephoto zoom button 105, 5 Function button 106, speaker 107, external output terminal 108, DC power input terminal 109, playback mode button 110, LCD monitor 111, the currently set shooting information on the monitor or LCD An LCD button 112, a manual focus button 113, a pause button 114, etc. for turning off / turning on the monitor are provided.

Here, the five function button 106 is provided with a menu entry / confirmation button and up, down, left, and right buttons at the center. When the menu is displayed on the monitor, the up, down, left and right buttons can function as special function buttons instead of directional movement.

The various function buttons shown in FIG. 4 may be provided to perform two or more complex functions in addition to the functions shown in the names.

Light incident through the digital camera optical system (OPS in FIG. 1) is photoelectrically converted in the photoelectric conversion unit (OEC in FIG. 1), AGC gain adjustment and digital signal in the CDS-ADC (1 in FIG. 1), and DSP It is displayed as a preview on the LCD monitor 111 through the AE control (7 of FIG. 1).

In the case where the digital camera displays an image of 30 frames per second in the preview, the exposure time of the preview image is about 30 msec maximum. If the preview image is dark even when the exposure time is maximized in the dark, the preview image is brightly corrected by adjusting the AGC gain.

The image displayed on the LCD monitor 111 of FIG. 4 is an image of a typical backlight condition in which the subject is facing the sun.

Under such backlight conditions, since the luminance of the entire image is high, the exposure time is reduced to, for example, 10 msec or less in the preview state. In this case, the luminance of the subject becomes relatively low.

FIG. 5 is a preview image displayed on the LCD monitor of FIG. 4, in which the AE control is performed at a low luminance while the background is very high in backlight. The flash mode is currently set to automatic mode. If it is determined in step S100 that the backlight condition is automatic mode, if the current flash mode is an automatic mode, it is stored (S102) and not in the prohibition of light emission mode (S104), and set to a forced light emission mode (S106).

6 shows a state in which the forced light emission mode is set by step S106.

FIG. 7 illustrates an image in which the subject part is brightly photographed in the forced light emission mode under the backlighting condition in step S108.

9 is a representation of the operation of the flash mode of the present invention. When the flash mode is an auto / slow synchro / red-eye reduction mode under backlight conditions, the flash mode is converted to the forced light emission mode by step S106. After the shooting is finished, the process returns to the previous flash mode by the step S110.

The above embodiments have been described with reference to a digital camera as an example of a digital image processing apparatus to which the present invention can be applied, but are not limited thereto. Those skilled in the art will appreciate that the present invention can be applied to a mobile phone, a personal digital assistant (PDA), etc., in which flash light is performed at the time of image capturing by embedding a digital camera function. In addition, the present invention can be applied to a portable multimedia player (PMP), which has recently been in the spotlight. PMP is a portable next-generation multimedia player with complex functions such as music playback, broadcast reception, games, electronic dictionary, video playback, digital camera and the like. As such, the concept of the present invention can be applied to a PMP in which a digital camera function is built and flash emission is performed during image capturing.

The best embodiments have been disclosed in the drawings and specification above. Although specific terms have been used herein, they are used only for the purpose of describing the present invention and are not used to limit the scope of the present invention as defined in the meaning or claims. Therefore, those skilled in the art will understand that various modifications and equivalent other embodiments are possible from this. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

As described above, according to the photographing method of the digital image processing apparatus of the present invention, the photographing by forced light emission is performed under backlight conditions, so that the photographed image is brighter.

The invention is not limited to the examples described above and represented in the drawings. Those skilled in the art taught by the above-described embodiments, many modifications to the above-described embodiments are possible by substitution, erasure, merging, etc. within the scope and object of the present invention described in the following claims.

Claims (3)

Determining whether it is a backlight condition; Storing the current flash mode when it is determined that the backlighting condition is performed; Determining whether the light emitting mode is inhibited; Changing the setting to a forced light emission mode when it is a backlight condition and not in the light emission inhibiting mode; Performing auto focusing and photographing; And And reducing the stored flash mode to a stored flash mode. The method of claim 1, A photographing method of a digital image processing apparatus, characterized by determining backlighting conditions using multi-part metering information. The method of claim 1, And the current flash mode is selected from the group consisting of an automatic mode, a red eye reduction mode, a forced flash mode, a slow synchro mode, and a flash off mode.

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