KR101398469B1 - Apparatus for digital picturing image - Google Patents

Abstract

The present invention relates to a digital image processing apparatus, and more particularly, to a digital image processing apparatus in which efficient auto focus is performed.

The present invention provides a digital image processing apparatus that provides a multi-AF (auto focus) function including a plurality of AF (auto focus) display areas and a plurality of AF (auto focus) Wherein at least a part of the AF area is disposed so as to overlap with another AF area of the AF area and an AF area of the AF area adjacent to the AF area, Device.

Description

[0001] Apparatus for digital picturing image [0002]

The present invention relates to a digital image processing apparatus, and more particularly, to a digital image processing apparatus in which efficient auto focus is performed.

Typically, the digital image processing apparatus includes all devices that process images of a digital camera, a PDA (personal digital assistant), a phone camera, a PC camera, or the like, or use motion recognition sensors. Such a digital image processing apparatus receives a desired image through an image pickup device, displays the input image on an image display device, displays the image on an image display device, stores the image as an image file by user's selection, and prints the stored image file.

Such a digital image processing apparatus is provided with an auto focus function. The auto focus function is a function of setting a composition toward a subject to be photographed and then automatically focusing the photographed image when the release button is operated.

Generally, an autofocusing apparatus usually processes an image obtained through a CCD (Charge Coupled Device) or CMOS (Complementary Metal Oxide Semiconductor) sensor to a digital image processing apparatus and then processes the acquired image by a High Pass Filter (HPF) The CPU extracts a focus value calculated through an edge passing through the focus lens in units of pictures and transfers the extracted focus value to a central processing unit (CPU). At this time, based on the calculated focus value, Lens movement direction and distance are determined, and an instruction is given to the actuator driver, whereby the actuator is driven to automatically focus the lens as it moves.

The conventional autofocus system has only one focus area (focus point), but the developed autofocus system has several focus areas. In other words, many cameras now have multiple autofocus areas on the frame, automatically detecting and focusing on the subject (usually focusing on the nearest object).

FIGS. 1A and 1B are views showing how auto focus is performed in a conventional digital image processing apparatus. FIG.

1A shows a conventional digital image processing apparatus having nine focus areas DA1 to DA9. When the user inputs the first shutter-release signal in a state in which the subject is framed as shown in Fig. 1A, the focus area DA2, DA3, DA5, DA6, DA8, DA9 ) Is displayed in the AF-OK area.

However, the auto focus function of such a conventional digital image processing apparatus has the following problems.

First, if at least a subject is included in each AF area, the AF area is displayed in the AF-OK area. 1, an AF-OK area is displayed on six focus areas DA2, DA3, DA5, DA6, DA8, and DA9. That is, there is a problem that an AF-OK area is unnecessarily displayed in an area much larger than an area where an actual subject exists. If a plurality of AF areas are displayed in the AF-OK area as described above, there is a high probability that the background will be included in the AF area other than the main subject. Therefore, the user may not know whether the subject is properly focused There was a problem.

Since the size of the auto-focus display areas DA1 to DA9 and the sizes of the auto focus calculation areas CA1 to CA9 are the same, when the edges are not included in the auto-focus display areas DA1 to DA9, There has been a problem that AF-NG occurs because the subject can not be detected in a similar pattern area such as clothes.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a digital image processing apparatus and an automatic control method thereof, in which efficient auto focus is performed.

The present invention provides a digital image processing apparatus that provides a multi-AF (auto focus) function including a plurality of AF (auto focus) display areas and a plurality of AF (auto focus) Wherein at least a part of the AF area is disposed so as to overlap with another AF area of the AF area and an AF area of the AF area adjacent to the AF area, Device.

In the present invention, the AF (auto focus) calculation area may be wider than the AF (auto focus) display area.

According to another aspect of the present invention, there is provided a method of controlling an AF (auto focus) display area in which at least a part of a plurality of AF (auto focus) display areas are displayed so as to overlap each other, And a digital signal processing unit for calculating a focus value in each of a plurality of AF (auto focus) calculation areas formed so as to have a larger area than the display area and calculating a moving direction and a distance of the focus lens, A digital image processing apparatus is provided.

According to the present invention, it is possible to obtain an effect of performing efficient auto focus in the digital image processing apparatus.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

2 is a perspective view showing the front and upper contours of the digital image processing apparatus according to the present invention.

The shutter-release button 101 is opened and closed to expose the CCD or film to light for a predetermined period of time, interlocked with an iris (not shown), and appropriately exposes the subject to record an image on the CCD.

The shutter-release button 101 generates the first and second image pickup signals by the photographer input. When the first shutter-release signal as the half-shutter signal is input, the digital image processing apparatus focuses and adjusts the amount of light. At this time, the display unit 113 is turned on green. When the first shutter-release signal is focused and the amount of light is adjusted, a second shutter-release signal as a full shutter signal is input to capture an image.

The power button 103 is input for supplying power to the digital image processing apparatus and operating it.

The flash 105 illuminates bright light instantly when shooting in a dark place. The flash mode includes automatic flash, forced flash, prohibited flash, red-eye reduction, and slow synchro flash.

The auxiliary light 107 supplies light to the subject so that the digital image processing apparatus can automatically and quickly catch the focus when the light amount is insufficient or at night.

The lens unit 109 receives light from an external light source and processes the image.

FIG. 3 is a rear view showing the rear external appearance of the digital image processing apparatus shown in FIG. 2. The wide angle-zoom button 111w, the telephoto-zoom button 111t, the display unit 113, Input buttons B1 to B14 (hereinafter referred to as buttons B1 to B14).

The wide-angle zoom button 111w or the tele-zoom button 111t widens the angle of view or narrows the angle of view depending on the input, in particular, when changing the size of the selected exposure area. When the wide angle-zoom button 111w is input, the size of the selected exposure area is reduced, and when the telephoto-zoom button 111t is input, the size of the selected exposure area is increased.

The buttons B1 to B14 are provided in the rows and columns of the display unit 113. [ The buttons B1 to B14 provided in the row and column of the display unit 113 are provided with a touch sensor (not shown) or a contact type switch (not shown).

That is, the touch sensors are provided on the buttons B1 to B14 to move up / down / left / right while touching the buttons B1 to B7 of the horizontal row or the buttons B8 to B14 of the vertical row, It is possible to select any value (e.g., color or brightness) of the items, or activate a submenu icon included in the main menu icon.

In addition, the button frames (B1 to B14) are provided with contact switches so that the main menu icon and the sub menu icon can be directly selected to execute the corresponding function. The touch sensor requires a relatively weak touch compared to the contact switch input, but the contact switch input requires a relatively strong touch compared to the touch sensor input.

FIG. 4 is a block diagram showing the configuration of the digital image processing apparatus shown in FIG. 2 and FIG. 3. The display unit 113, the user input unit 121, the image pickup unit 123, the image processing unit 125, 127 and a digital signal processing unit 129. [

The user input unit 121 includes a shutter-release button 101 that is opened and closed to expose a CCD or a film to light for a predetermined period of time, a power button 103 that inputs power to supply power, A wide angle-zoom button 111w and a telephoto-zoom button 111t for narrowing the angle of view and a touch sensor or a contact switch provided in the horizontal and vertical columns around the display unit 113 for setting characters or menus There are buttons B1 to B14.

The image pickup section 123 includes a shutter, a lens section, a diaphragm, a charge coupled device (CCD), and an analog-to-digital converter (ADC), not shown. The shutter is a mechanism that adjusts the amount of light that is exposed with the iris. The lens unit receives light from an external light source and processes the image. At this time, the diaphragm adjusts the amount (amount of light) of the incident light according to the degree of opening and closing. The opening / closing degree of the diaphragm is controlled by the digital signal processor 129.

The CCD accumulates the amount of light input through the lens unit and outputs the image captured by the lens unit according to the accumulated light amount in accordance with the vertical synchronization signal. Image acquisition of a digital image processing device is performed by a CCD which converts the light reflected from the subject into an electrical signal. In order to obtain a color image using a CCD, a color filter is required, and a filter (not shown) called a color filter array (CFA) is employed in most cases. CFA has a regularly arranged structure that passes only light that represents one color per pixel, and it has various forms according to the arrangement structure. The ADC converts the analog video signal output from the CCD into a digital signal.

The image processing unit 125 processes the digitally converted RAW data so that it can be displayed. The image processing unit 125 removes the black level due to the dark current generated in the CCD and the CFA filter which are full of temperature change. The image processing unit 125 performs gamma correction to encode information according to the non-linearity of human vision. The image processing unit 125 performs CFA interpolation for interpolating a Bayer pattern embodied with RGAG lines and GBGB lines of gamma-corrected predetermined data into RGB lines. The image processing unit 125 converts the interpolated RGB signals into YUV signals, edge-compensates the Y signals by filtering the Y signals by a high-pass filter, and calculates the color values of the U and V signals using a standard color coordinate system Corrects the color correction, and removes these noises. The image processing unit 125 compresses and processes the noise-canceled Y, U, and V signals to generate a JPEG file, and the generated JPEG file is displayed on the display unit 113 and stored in the storage unit 127 . All the operations of the image processing unit 125 operate under the control of the digital signal processing unit 129. [

The digital signal processor 129 controls at least a part of a plurality of AF (auto focus) display areas to be displayed so as to overlap with each other and displays the AF (auto focus) display area corresponding to each of the plurality of AF Calculates a focus value in each of a plurality of AF (auto focus) calculation regions formed so as to have an area wider than an area, and calculates a moving direction and a distance of the focus lens.

Auto focus is a function of an optical system (camera) that automatically focuses on a specific object (subject). Most compact digital cameras currently in development use TTL contrast detection. In the case of a compact digital camera, it does not have a separate auto-focus sensor but analyzes the contrast of the image obtained through the image CCD / CMOS image sensor and focuses it. On the other hand, most digital SLR cameras currently in development use TTL phase difference detection.

The autofocus method is largely divided into an active system and a passive system. An active system is called 'active' because the camera emits ultrasound or infrared radiation for distance measurements. On the other hand, a passive system focuses light using naturally reflected light from an object.

Such conventional autofocusing apparatus has only one focus region (focus point), but the advanced autofocus system has several focus regions. In other words, many of the cameras currently developed have multiple auto focus areas on a frame (screen), and provide a multi auto focus function that automatically detects and focuses on a subject.

However, in such a conventional digital image processing apparatus that provides a multi-auto focus function, when a subject is included in each AF area, the AF area is displayed as an AF-OK area. That is, there is a problem that an AF-OK area is unnecessarily displayed in an area much larger than an area where an actual subject exists. Further, since the size of the auto-focus display area is the same as the size of the auto-focus calculation area, if the edge is not included in the auto-focus display area or the subject is not detected in a similar pattern area such as a face or clothes, There is a problem that -NG occurs.

In order to solve such a problem of the conventional digital image processing apparatus, a digital image processing apparatus according to an embodiment of the present invention includes an auto focus (AF) display region among a plurality of AF display regions, (auto focus) display area and at least a part of another neighboring AF (auto focus) display area overlap each other.

FIGS. 5A to 5C are diagrams showing how auto focus is performed in the digital image processing apparatus according to the present invention. FIG.

Referring to FIG. 5A, in the digital image processing apparatus according to the present invention, each AF (auto focus) display region is arranged so that at least a part thereof overlaps with the neighboring AF (auto focus) display region.

Specifically, FIG. 5A shows a total of fifteen AF (auto focus) display areas, five in one column. The first AF display area DA1, the second AF display area DA2, and the third AF display area DA3 are located in the uppermost row in the AF area (auto focus) Similarly, they are spaced apart from each other at regular intervals. A fourth AF display area DA4 is disposed between the first AF display area DA1 and the second AF display area DA2 and the second AF display area DA2 and the third AF display area DA2 And the fifth AF display area DA5 is disposed between the first and second AF display areas DA1 and DA3.

Therefore, the first AF display area DA1 and the fourth AF display area DA4, which are adjacent to each other, are partially overlapped with each other, and the fourth AF display area DA4 and the second AF display area DA2 A part of the second AF display area DA2 and the part of the fifth AF display area DA5 overlap with each other and the fifth AF display area DA5 and the fourth AF display area DA4 Are arranged so as to overlap each other.

According to the structure of the present invention as described above, the AF-OK region is displayed only in the region where the subject exists by adding the AF display region so that adjacent AF display regions overlap each other.

5A, the fourth AF display area DA4 and the fifth AF display area DA5 are closer to the first AF display area DA1, the second AF display area DA2, and the third AF display area DA3 However, it is for convenience of explanation, and it is preferable that the AF display areas DA1 to DA5 are actually formed in the same manner.

In FIG. 5A, only the AF display areas arranged in one row are shown to be overlapped with each other. However, the present invention is not limited to this, and the AF display areas arranged in one row , And may be arranged so as to overlap with each other between the AF display areas located in the diagonal direction.

Referring to FIG. 5B, in the digital image processing apparatus according to the present invention, each AF (auto focus) operation region is arranged so that at least a part thereof overlaps with the neighboring AF (auto focus) operation region. The AF (auto focus) operation area is formed wider than the AF (auto focus) display area.

Specifically, FIG. 5B shows a total of fifteen AF (auto focus) operation areas, five in one column. The first AF operation area CA1, the second AF operation area CA2, and the third AF operation area CA3 are the same as those of the conventional digital image processing device Similarly, they are spaced apart from each other at regular intervals. A fourth AF operation area CA4 is disposed between the first AF operation area CA1 and the second AF operation area CA2 and the second AF operation area CA2 and the third AF operation area CA3 , A fifth AF operation area CA5 is arranged.

Therefore, the first AF operation area CA1 and the fourth AF operation area CA4, which are adjacent to each other, are arranged so as to overlap with each other, and the fourth AF operation area CA4 and the second AF operation area CA2 And a part of the second AF operation area CA2 and the fifth AF operation area CA5 overlap with each other and the fifth AF operation area CA5 and the fourth AF operation area CA4 Are arranged so as to overlap each other.

Here, the digital image processing apparatus according to the present invention is characterized in that an AF (auto focus) operation area is formed wider than an AF (auto focus) display area. More specifically, the digital signal processor 129 controls the plurality of AF calculation areas CA1 to CA5 to be formed so as to correspond to the plurality of AF display areas DA1 to DA5, respectively, and the AF calculation areas CA1 to CA5, Is formed to be wider than the AF display areas DA1 to DA5. Then, a focus value is calculated in each of the plurality of AF operation areas CA1 to CA5, and the movement direction and the distance of the focus lens are calculated.

As described above, since the AF (auto focus) calculation area is formed wider than the AF (auto focus) display area, the probability of including an edge in the AF (auto focus) calculation area is increased and AF- NG occurs because the subject can not be detected And the reliability of photographing is improved.

5B, the fourth AF operation area CA4 and the fifth AF operation area CA5 are slightly thicker than the first AF operation area CA1, the second AF operation area CA2 and the third AF operation area CA3 However, this is for convenience of explanation, and it is preferable that the AF calculation regions CA1 to CA5 are actually formed in the same manner.

5B, only the AF calculation regions arranged in one row are shown to be overlapped with each other. However, the present invention is not limited to this, and the AF calculation regions arranged in one row , And further, the AF calculation regions located in the diagonal direction may be arranged to overlap with each other.

FIG. 5C is a view showing an auto focus performed using the digital image processing apparatus according to the present invention. FIG.

When the user inputs the first shutter-release signal in a state in which the subject is framed as shown in Figs. 5A and 5B, the focus areas DA5, DA6, and DA7, in which the subject is located, -OK area.

That is, in the conventional digital image processing apparatus, when photographs are taken in the same composition, the AF-OK area is displayed on six focus areas DA2, DA3, DA5, DA6, DA8 and DA9, The AF-OK area is unnecessarily displayed in a much wider area than the AF-OK area. On the other hand, in the digital image processing apparatus according to the present invention, by adding an AF display area so that neighboring AF display areas overlap each other, the area where the subject exists, that is, the three focus areas DA5, DA6, Only the AF-OK area is displayed.

Further, since the AF (auto focus) calculation area is wider than the AF (auto focus) display area, there is a high possibility that the edge is included in the AF (auto focus) calculation area and AF-NG occurs because the subject can not be detected And the reliability of photographing is improved.

The present invention has been described with reference to the preferred embodiments. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. Therefore, the disclosed embodiments should be considered in an illustrative rather than a restrictive sense. The scope of the present invention is defined by the appended claims rather than by the foregoing description, and all differences within the scope of equivalents thereof should be construed as being included in the present invention.

FIGS. 1A and 1B are views showing how auto focus is performed in a conventional digital image processing apparatus. FIG.

2 is a perspective view showing the front and upper contours of the digital image processing apparatus according to the present invention.

3 is a rear view showing the rear external appearance of the digital image processing apparatus shown in FIG.

FIG. 4 is a block diagram showing a configuration of the digital image processing apparatus shown in FIG. 2 and FIG. 3. FIG.

FIGS. 5A to 5C are diagrams showing how auto focus is performed in the digital image processing apparatus according to the present invention. FIG.

Description of the Related Art

100: digital image processing apparatus 121: user input unit

123: image pickup unit 125: image processing unit

127: storage unit 129: digital signal processor

Claims (3)

1. A digital image processing apparatus that provides a multi-AF (auto focus) function including a plurality of AF (auto focus) display areas and a plurality of AF (auto focus) At least a part of the plurality of AF display areas is arranged so that at least a part of the plurality of AF display areas is overlapped with an auto focus display area in the middle of the plurality of AF display areas and another auto focus display area neighboring the one auto focus display area A digital image processing apparatus comprising: Wherein the AF (auto focus) operation area is formed wider than the AF (auto focus) display area. delete Controls at least a part of a plurality of AF (auto focus) display areas to be overlaid and displayed, A focus value is calculated in each of a plurality of AF (auto focus) operation regions corresponding to the plurality of AF (auto focus) display regions and formed in a larger area than the respective AF (auto focus) And a digital signal processing section for controlling to calculate a moving direction and a distance of the focus lens.

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