KR20150118719A - Auto Focus Data Appartus and Methode for Spot Light Picture - Google Patents

Abstract

The present invention relates to an apparatus and a method for detecting auto focus data on a partial high brightness image. In an apparatus for detecting auto focus data used for an auto focus performing device which comprises: a lens unit (11), an image sensor unit (12), an analog front end (AFE) unit (13), an image signal processor (ISP) unit (14), a timing generator (TG) unit (15), a signal driver (16), an auto focus detector (AFD) unit (17), a lens driving driver (18), a lens driving motor unit (19), and a main control device (20), the apparatus for detecting auto focus data on a low illumination image comprises: a histogram analysis (H/A) unit (110) for receiving an image signal delivered from the ISP unit (14), and analyzing pixel distribution according to the illumination; and a low shutter speed (L/S) control unit (120) for delivering the image signal to the AFD unit (17) by processing auto focus data after decreasing the brightness of the image signal by controlling the shutter speed faster when the image signal determined as a partial high brightness image in the H/A unit (110).

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an auto focus data detection apparatus and method for a partial high-

The present invention relates to a method and an apparatus for detecting an autofocus data for a partial high-definition image and includes a lens unit 11, an image sensor unit 12, an AFE (Analog Front End) unit An image signal processor (ISP) 14, a timing generator (TG) 15, a signal driver 16, an AFD (Auto Focus Detector) An autofocus data detecting device for use in an autofocus implementing apparatus including a lens unit (17), a lens drive driver (18), a lens drive motor unit (19), and a main controller (20)

A histogram analyzer (H / A: Histogram Analysis) unit 110 for analyzing a pixel distribution different in illuminance by receiving an image signal transmitted from the image signal processor (ISP) unit 14, If it is determined by the analysis (H / A: Histogram Analysis) unit 110 that the image is a partial high definition image, the shutter speed is rapidly adjusted to reduce the brightness of the image signal, A shutter speed (S / S) control unit 120 for transmitting the shutter speed signal to a focus detector unit 17; And a method of detecting autofocus data of a partial high-definition image using the apparatus.

Up to now, image pickup devices such as digital still cameras and digital video cameras having an image pickup device such as a charge coupled device (CCD) sensor or a complementary metal oxide semiconductor (CMOS) sensor have been actually used.

As an existing invention for realizing an autofocus function in such a video apparatus, there is known an autofocus control circuit, an autofocus control method and an image pickup apparatus (Korean Patent Registration No. 10-0969831) "Autofocus control apparatus and method, recording medium and program (Korean Patent Laid-Open No. 10-2006-0129422)"

The autofocusing apparatus of the present invention includes a lens unit 11, an image sensor unit 12, an AFE (analog front end) unit 11, An image signal processor (ISP) unit 14, a timing generator (TG) unit 15, a signal driver 16, an AFD (Auto Focus Detector) ) Portion 17, a lens driving driver 18, a lens driving motor portion 19, and a main controller 20.

The autofocusing process of the present invention will be briefly described as follows.

First, when a light signal is incident through the lens unit 11, a TG (Timing Generator) block (Timing Generator (TG)) 15 generates and supplies a frequency clock so that each block can perform signal processing . Thereafter, the image sensor unit 12 receiving the necessary clock from the TG converts the light signal into an electrical signal, and transmits the converted signal to the AFE (Analog Front End) block 13 .

Next, in the AFE block, noise is removed in order to extract a net signal from the transmitted signal, and the signal is amplified to meet the environment to brighten the image. After the signal processing, the analog signal is converted into a digital signal and transmitted to an ISP (Image Signal Processor) block 14 (Image Signal Processor).

In the ISP block, the transmitted signal is subjected to video signal processing according to the standard, and necessary camera functions are implemented.

Meanwhile, the ISP transmits data to implement the main controller unit (MCU) autofocus algorithm so as to implement autofocus. This function is performed by the AFD (Auto Focus Detector) unit 17, and receives the image signal. Thereafter, the main controller 20 receives the data and drives the lens through the lens driving driver 18 and the lens driving motor unit 190 so as to obtain the optimum focus.

In this case, the AFD unit 13 generates data using the brightness signal among the image signals. The brightness of the generated data is such that the brightness of the brightness is not saturated, so that appropriate data can be generated. However, as shown in FIG. 1, when light is too bright and saturates as in the case of a partial high-definition image (for example, when a spot light source is present), appropriate data may not be generated.

Patent Document 1: Korean Patent No. 10-0969831 Patent Document 2: Korean Patent Laid-Open No. 10-2006-0129422

The present invention solves the above-mentioned problems of the prior art, and determines the case of the partial high-definition image by analyzing the histogram showing the distribution of the pixels according to the illuminance in the captured image, and then controls the shutter speed And an object of the present invention is to provide an autofocus data detection method and apparatus for a partial high definition image which realizes a saturated image as an unsaturated image and enables proper auto focusing.

In order to achieve the above object, an autofocus data detecting apparatus for a partial high definition image of the present invention includes a lens unit 11, an image sensor unit 12, an analog front end (AFE) ) Unit 13, an image signal processor (ISP) unit 14, a timing generator (TG) unit 15, a signal driver 16, an AFD (Auto) An autofocus data detecting apparatus used in an autofocus implementing apparatus including a focus detector unit (17), a lens drive driver (18), a lens drive motor unit (19), and a main controller (20)

A histogram analyzer (H / A: Histogram Analysis) unit 110 for analyzing a pixel distribution different in illuminance by receiving an image signal transmitted from the image signal processor (ISP) unit 14, If it is determined by the analysis (H / A: Histogram Analysis) unit 110 that the image is a partial high definition image, the shutter speed is rapidly adjusted to reduce the brightness of the image signal, A shutter speed (S / S) control unit 120 for transmitting the shutter speed signal to a focus detector unit 17; And a control unit.

Further, under the control of the main controller 20,

The CPU 11 selects any one of autofocus data transmitted from the image signal processor (ISP) unit 14 or autofocus data processed by the shutter speed (S / S) A signal selection unit 130 for delivering the signal to the AFD unit 17; And further comprising:

According to another aspect of the present invention, there is provided an autofocus data detection method for a partial high-

A histogram analyzing step (S1) of analyzing a pixel distribution different in illuminance by receiving an image signal transmitted from the image signal processor (ISP) section (14);

A step S2 of determining whether the image signal is a partial high-definition image from the histogram analysis step S1;

If the image signal is judged to be a partial high definition image in the partial high brightness image determination step S2, the shutter speed is rapidly adjusted to reduce the brightness of the image signal to be processed into autofocus data, Focus Detector) 17 (step S3); And a control unit.

In addition, when it is determined that the brightness of the autofocus data processed in the shutter speed adjusting step S3 is still lighter than the predetermined brightness range, the autofocus data correcting step S3 for performing the shutter speed adjusting step S3 again Determining step S4; And further comprising:

The partial high-brightness image determination step S2 may include determining that the image signal is a partial high-brightness image when the number of pixels A distributed over a predetermined high contrast range (a) on the histogram is equal to or greater than a predetermined ratio .

The predetermined ratio is characterized in that the number of pixels (A) distributed over the predetermined high luminance range (a) of the total number of pixels is 1/128 or more.

According to the present invention, after the histogram analysis showing the distribution of the pixels according to the illuminance in the photographed image, the partial high-definition image is determined, and in the case of the partial high-definition image, the saturated image is saturated through the shutter speed control It is possible to provide an autofocus data detection method and apparatus for a partial high-definition image which can be implemented as a non-image and enable proper autofocusing.

1: a drawing showing a case of a partial high-definition image (for example, when a spot light source is present)
2 is a block diagram illustrating a configuration of an autofocus data detecting apparatus for a partial high-definition image according to an exemplary embodiment of the present invention.
3 is a flowchart showing a method of detecting autofocus data for a partial high-definition image according to an embodiment of the present invention;
Figure 4: Analysis of the histogram distribution of Figure 1;

Hereinafter, an apparatus and method for detecting autofocus data for a partial high-definition image according to an exemplary embodiment of the present invention will be described in detail. First, it should be noted that, in the drawings, the same components or parts are denoted by the same reference numerals whenever possible. In describing the present invention, a detailed description of known functions and configurations incorporated herein will be omitted so as to avoid obscuring the subject matter of the present invention.

First, an autofocus data detecting apparatus for a partial high definition image according to an embodiment of the present invention will be described. 2, the autofocus data detecting apparatus for a partial high definition image according to an exemplary embodiment of the present invention includes a lens unit 11, an image sensor unit 12, an AFE An analog front end unit 13, an image signal processor (ISP) unit 14, a timing generator (TG) unit 15, a signal driver 16, An autofocus data detecting apparatus used in an autofocus implementing apparatus including an AFD (Auto Focus Detector) unit 17, a lens driving driver 18, a lens driving motor unit 19 and a main controller 20 (H / A) histogram analysis unit 110 and a shutter speed (S / S) control unit 120. The histogram analysis unit 110 includes a histogram analysis unit 110 and a shutter speed control unit 120.

As shown in FIG. 2, the histogram analysis unit 110 receives a video signal transmitted from the image signal processor (ISP) unit 14, And histogram analysis (H / A: Histogram Analysis) for analyzing the distribution. Here, the histogram indicates the number of pixels according to the illuminance in the image as shown in FIG. In this case, in the case of a partial high-definition image (for example, an image in which a spotlight exists as shown in Fig. 1) as shown in Fig. 1, 1) a light source, 2) There may be a dark background in which the light of the light source does not reach, and the characteristics of such an image appear as areas represented by "A", "B", and "C" on the histogram in FIG.

In the case of such a partial high definition image, if the number of pixels A distributed in the predetermined high contrast period a indicated by the dotted line " a "in Fig. 4 exceeds a predetermined ratio (for example, %). In this case, it is preferable that the predetermined ratio is set so that the number of pixels (A) distributed over the predetermined high contrast period (a) of the total number of pixels is 1/128 or more, in consideration of the characteristics of the partial high- .

Accordingly, the histogram analysis unit 110 may determine that the number of pixels A distributed over a predetermined high contrast period (a) on the histogram is equal to or greater than a predetermined ratio, It is desirable to perform a function of determining that the image is a video.

The shutter speed controller 120 is connected to the histogram analyzer 110 and the main controller 20 as shown in FIG. 2, If it is determined by the histogram analysis unit 110 that the image is a partial high-definition image, the shutter speed is rapidly adjusted to reduce the brightness of the image signal, and the AF signal is processed into autofocus data, : Auto Focus Detector) unit 17 as shown in FIG.

2, according to the control of the main controller 20, the autofocus data detecting apparatus for a partial high definition image according to an embodiment of the present invention includes an image signal processor (ISP) (AFD) unit 14 and the autofocus data processed by the shutter speed (S / S) shutter control unit 120, And a signal selection unit 130 for transmitting the signal to the auto focus detector unit 17.

Hereinafter, a method of detecting autofocus data for a partial high-definition image according to an embodiment of the present invention will be described.

As shown in FIG. 3, the autofocus data detection method for a partial high definition image according to an exemplary embodiment of the present invention includes steps S0a to S0e of inputting a light signal to an existing lens, And a shutter speed adjusting step (S3) between the focus data extracting step (S0f) and the autofocus implementing step (S0i). The histogram analyzing step (S1) .

The histogram analysis step S1 is a step of analyzing pixel distributions different in illuminance from the image signal transmitted from the image signal processor (ISP) 14. That is, the histogram pattern is formed by analyzing the distribution of the pixels according to the illuminance in the image signal.

Thereafter, using the histogram pattern received from the histogram analysis step S1, a partial high image quality image determination step S2 is performed to determine whether the image signal is a partial high image quality image.

In this case, as described above, the partial high-brightness image determination step S2 may be performed when the number of pixels A distributed over a predetermined high contrast range (a) on the histogram is equal to or greater than a predetermined ratio, It is preferable to judge that the image is a still image. In this case, it is preferable that the predetermined ratio is set so that the number of pixels (A) distributed over the predetermined high contrast period (a) of the total number of pixels is 1/128 or more, in consideration of the characteristics of the partial high- .

Next, if it is determined that the image signal is a partial high-brightness image in the partial high-brightness image determination step S2, the brightness of the image signal is reduced by rapidly adjusting the shutter speed to process the AF signal, AFD (Auto Focus Detector) unit 17, as shown in FIG.

In this case, when it is determined that the brightness of the autofocus data processed in the shutter speed adjusting step S3 is still lighter than the predetermined brightness range, the autofocus data for performing the shutter speed adjusting step S3 again It is preferable to further comprise an appropriate judgment step S4.

According to the present invention having the above-described configuration, after the histogram analysis of the pixel distribution according to the illuminance in the photographed image, the partial high-definition image is determined, and in the case of the partial high-definition image, It is possible to provide an autofocus data detection method and apparatus for a partial high-definition image that realizes proper autofocusing by realizing an image that is not saturated.

Best Mode for Carrying Out the Invention Best modes have been disclosed in the drawings and specification. Although specific terms have been employed herein, they are used for purposes of illustration only and are not intended to limit the scope of the invention as defined in the claims or the claims. Therefore, those skilled in the art will appreciate that various modifications and equivalent embodiments are possible without departing from the scope of the present invention. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

11: Lens part
12: Image sensor section
13: Analog Front End (AFE) section
14: Image Signal Processor (ISP)
15: Timing Generator (TG)
16: Signal Driver
17: AFD (Auto Focus Detector)
18: Lens drive driver
19: Lens drive motor section
20:
100: Auto focus data detection device
110: Histogram analysis (H / A)
120: shutter speed (S / S)
130: Signal selector

Claims (5)

A lens unit 11, an image sensor unit 12, an AFE (Analog Front End) unit 13, an image signal processor (ISP) unit 14, (TG) unit 15, a signal driver 16, an AFD (Auto Focus Detector) unit 17, a lens driving driver 18, a lens driving motor unit 19, An autofocus data detecting apparatus used in an autofocus implementing apparatus including a main controller (20), comprising:
A histogram analysis (H / A: Histogram Analysis) unit 110 for receiving a video signal transmitted from the image signal processor (ISP) unit 14 and analyzing pixel distributions different in illuminance;
If it is determined by the histogram analysis unit 110 that the image is a partial high-definition image, the shutter speed is rapidly adjusted to reduce the brightness of the image signal, and the AF signal is processed into autofocus data, : A shutter speed (S / S) control unit 120 for delivering the shutter speed to an auto focus detector unit 17; (100) for a partial high-definition image.
The method according to claim 1,
Under the control of the main controller 20,
The CPU 11 selects any one of autofocus data transmitted from the image signal processor (ISP) unit 14 or autofocus data processed by the shutter speed (S / S) A signal selection unit 130 for delivering the signal to the AFD unit 17; (100) for a partial high-definition image. ≪ IMAGE >
An autofocus data detecting method using the autofocus data detecting apparatus (100) according to claim 1,
A histogram analyzing step (S1) of analyzing a pixel distribution according to illuminance by receiving an image signal transmitted from the image signal processor (ISP) 14;
A step S2 of determining whether the image signal is a partial high-definition image from the histogram analysis step S1;
If the image signal is judged to be a partial high definition image in the partial high brightness image determination step S2, the shutter speed is rapidly adjusted to reduce the brightness of the image signal to be processed into autofocus data, Focus Detector) 17 (step S3); And a second step of detecting the autofocus data.
The method of claim 3,
(S3) again when it is determined that the brightness of the autofocus data processed in the shutter speed adjusting step (S3) is still lighter than the predetermined brightness range (S4); And a step of detecting the autofocus data.
The method according to claim 3 or 4,
The partial high brightness image determination step S2 may include determining that the image signal is a partial high brightness image when the number of pixels A distributed over a predetermined high contrast range a on the histogram is equal to or higher than a predetermined ratio However,
Wherein the predetermined ratio is the number of pixels (A) distributed over the predetermined high contrast range (a) of the total number of pixels is 1/128 or more.

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