JP2013072988A - Compound eye camera, continuous automatic focus control method using the same, control program and readable storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve response of AF and image quality when photographing in a monocular mode with continuous AF.SOLUTION: The compound eye camera includes a data processing part 61 for focus which, when focusing continuously from the time when focus control and focusing are performed at a first imaging part 11, determines a lens driving direction of the first imaging part 11 and performs the focus control, on the basis of correlation between a data amount from the first imaging part 11 and a data amount from a second imaging part 12, in a state where a lens position of the second imaging part 12 is shifted forward or backward from a focusing state by a predetermined amount D.

Description

  The present invention has a compound eye camera that has at least two imaging optical systems on the left and right and enables stereoscopic imaging, a continuous automatic focusing control method using the same, and each step of the continuous automatic focusing control method is executed on a computer The present invention relates to a control program in which a processing procedure for causing the control program is described, and a computer-readable readable storage medium storing the control program.

  This type of conventional compound-eye camera is applied to, for example, a digital camera, performs autofocus AF operation with one monocular of two imaging optical systems on the left and right, and displays an image captured with the other monocular on the display screen. Is displayed. The focus for the through image displayed on the display screen is adjusted according to the result value of the AF at the timing when the focus is achieved with one AF monocular, and the two imaging optical systems on the left and right are aligned. Such a conventional compound eye camera is disclosed in Patent Document 1.

  FIG. 4 is a block diagram illustrating a configuration example of a main part of a conventional compound eye camera disclosed in Patent Document 1. In FIG.

  In FIG. 4, in the conventional compound-eye camera 100, a CPU 101 as a control unit controls each unit of the compound-eye camera 100 by executing a predetermined control program based on an input operation from the operation unit 102.

  The compound-eye camera 100 includes a ROM (not shown), and various data necessary for control are recorded in the ROM in addition to a control program executed by the CPU 101. The CPU 101 controls each part of the compound eye camera 100 by reading the control program recorded in the ROM into the main memory 103 and sequentially executing it.

  The main memory 103 is composed of a RAM, and is used as a control program execution processing area, a temporary storage area for image data, and various work areas.

  The operation unit 102 includes a power button, a shutter release button, a shooting mode / playback mode switch, and the like (not shown), and outputs a signal corresponding to each operation command to the CPU 101. For example, the shutter release button has a switch that is turned on when half-pressed to prepare for photographing such as focus lock and photometry, and a switch that is turned on when fully pressed to capture an image.

  The first imaging optical system of the left and right imaging optical systems includes a lens 104, a lens driving unit 105, an imaging element 106, and an imaging element driving unit 107. The lens 104 includes a zoom lens, a focus lens, a diaphragm, a mechanical shutter, and the like (not shown), and is driven by a lens driving unit 105 to perform zooming, focusing, aperture opening amount (F value) change, and mechanical shutter opening / closing operations. It has become.

  The image sensor 106 is disposed on the rear stage side of the lens 104 and receives the subject light transmitted through the lens 104 and images the subject light. On the light receiving surface of the image sensor 106, a large number of light receiving portions (not shown) are two-dimensionally arranged in a matrix in the matrix direction, and red (R) and green (G) (not shown) corresponding to each light receiving portion. , Blue (B) primary color filters are arranged in a predetermined arrangement structure. The subject light imaged on the light receiving surface is converted into an electrical signal by each light receiving element and accumulated.

  The electrical signal accumulated in each light receiving unit is read out to a vertical transfer path (not shown). The vertical transfer path transfers this image pickup signal line by line in the vertical transfer direction in synchronization with the clock supplied from the image pickup element driving unit 107. Thereafter, each image signal for one line is output to the image signal processing unit 108 in synchronization with a clock supplied from the image sensor driving unit 107.

  The second imaging optical system has the same configuration as that of the first imaging optical system. The subject light transmitted through the lens 104 is converted into an electrical signal by each light receiving unit of the image sensor 106 and output to the image signal processor 108.

  Note that, as a through image displayed on the display screen of the display unit 109, an imaging signal captured by the second imaging optical system is used. When the conventional compound-eye camera 100 is set to the photographing mode, output of an image signal is started in order to display a through image on the display unit 109. The output of the image signal for the through image is temporarily stopped when the instruction for the main photographing is given, and is started again when the main photographing is finished. At the end of the main shooting, the captured image is displayed on the display unit 109 for a predetermined time (post view). The user can confirm whether or not the captured image has been properly captured by confirming the postview.

  The imaging signal processing unit 108 includes a correlated double sampling circuit (CDS), a clamp processing circuit, an automatic gain control circuit (AGC), and an A / D converter (not shown).

  The CDS removes noise included in each image signal from each image sensor 106. The clamp processing circuit performs processing for removing dark current components. Further, the AGC amplifies the imaging signal from which the dark current component has been removed with a predetermined gain corresponding to the set imaging sensitivity (ISO sensitivity). The analog image signal subjected to the required signal processing is converted into a digital image signal having a gradation width of a predetermined bit by an A / D converter. This image signal is so-called RAW data, and has a gradation value indicating the density of R, G, and B for each pixel. This digital image signal is stored in the main memory 103 via the data bus 110 and the memory control unit 111.

  In addition to the memory control unit 111, the data bus 110 and the control bus 112 include a digital signal processing unit 113, a compression / decompression processing unit 114, an integration unit 115, an external memory control unit 116, a display control unit 117, an AF processing unit 118, and the like. Each processing unit is connected so that information can be transmitted / received to / from each other via the data bus 110 based on a control signal of the control bus 112.

  The digital signal processing unit 113 performs predetermined signal processing on the image signals of R, G, and B colors stored in the main memory 103, and an image signal (Y that includes the luminance signal Y and the color difference signals Cr and Cb). / C signal).

  The compression / decompression processing unit 114 performs compression processing in a predetermined format (for example, JPEG) on an image signal (Y / C signal) including the input luminance signal Y and color difference signals Cr and Cb in accordance with a compression command from the CPU 101. Generate compressed image data. In addition, in accordance with a decompression command from the CPU 101, the input compressed image data is subjected to a decompression process in a predetermined format to generate uncompressed image data.

  The accumulating unit 115 takes in R, G, and B image signals stored in the main memory 103 in accordance with a command from the CPU 101, and calculates an accumulated value necessary for AE control. The CPU 101 calculates a luminance value from the integrated value, and obtains an exposure value from the calculated luminance value. Further, the aperture value and the shutter speed are determined from the exposure value according to a predetermined program diagram.

  The external memory control unit 116 controls reading / writing of data with respect to the recording medium 119 in accordance with a command from the CPU 101. The recording medium 119 may be detachable from the main body of the compound eye camera 100 such as a memory card, or may be built into the main body of the compound eye camera 100. When the recording medium 119 is detachable, a card slot is provided in the main body of the compound eye camera 100, and the recording medium 119 is loaded into the card slot for use.

  The display control unit 117 controls display on the display unit 109 in accordance with a command from the CPU 101. The display unit 109 can display a moving image (through image) and can be used as an electronic viewfinder, and can display a captured image (post-view image) and a reproduced image read from the recording medium 119. It is a monitor. The display unit 109 can display the left and right images captured simultaneously in the first imaging optical system and the second imaging optical system with directivity alternately in a time-sharing manner. It is also possible for the user to stereoscopically view the image. The display unit 109 can also be used as a user interface display screen using a touch panel. Further, the autofocus AF operation is performed with one monocular of the left and right imaging optical systems, and the display control unit 117 may display an image captured with the other monocular on the display screen of the display unit 109. it can.

  The AF processing unit 118 performs the AF lens operation with one monocular of the left and right imaging optical systems and stores the first imaging optical for AF stored in the main memory 103 during the AF processing in accordance with a command from the CPU 101. A focus evaluation value necessary for AF (Automatic Focus) control is calculated based on the system image signal. The AF processing unit 118 includes a main subject extraction unit that extracts a main subject in the shooting screen as a focus region, a focus region extraction unit that extracts a signal in the focus region, and an integration unit that integrates absolute value data in the focus region. In addition, the absolute value data in the focus area integrated by the integration unit is output to the CPU 101 as a focus evaluation value. During the AF control, the CPU 101 searches for a position where the focus evaluation value output from the AF processing unit 118 becomes a maximum, and the lens 104 of the first imaging optical system and the lens 104 of the second imaging optical system are located at the maximum position. By moving it, focusing on the main subject is performed.

  As described above, in the conventional compound-eye camera 100, the focus lens (not shown) in the lens 104 of the second imaging optical system is moved based on the focus evaluation value calculated from the image signal of the first imaging optical system, and the lens 104 is moved. Focusing.

JP 2010-134291 A

  In the conventional compound-eye camera 100 disclosed in Patent Document 1, as shown in FIG. 5, the image when the lens 104 moves during AF does not have to be shown as a through image. The operation is the same as that performed, and the following problems occur when continuous AF is performed. 4 and 5, the lens driving unit 105 in FIG. 4 includes the lens driving motor 105a and the motor control unit 105b in FIG. 5, and the AF processing unit 118 and the CPU 101 in FIG. This corresponds to the data processing unit 121 for use. The signal processing unit 120 in FIG. 5 includes the CPU 101, the imaging signal processing unit 108, the memory control unit 111, the digital signal processing unit 113, the compression / decompression processing unit 114, the integration unit 115, the display control unit 117, and the AF processing unit 118 in FIG. It corresponds to.

  First, in the AF process, it is necessary to determine that a focus shift has occurred when a change in the data amount thereafter is detected based on the focus data amount (peak value) once in focus. For this reason, when the subject is in focus but the subject has changed significantly, the amount of data changes, and it is misrecognized that the focus has shifted, and the lens position is swept again to focus. It was necessary to realign.

  Next, if there is a real shift in focus, the amount of data will decrease, but it will not be possible to determine whether the subject has shifted far or near, and it will be necessary to sweep the lens position again to refocus. . For this reason, there is a large time lag until the AF result is reflected in the focus position for image through.

  The present invention solves the above-described conventional problems, and a compound-eye camera that can improve AF response and improve image quality when shooting using continuous AF in a monocular mode, and the same A continuous automatic focusing control method using a computer, a control program describing a processing procedure for causing a computer to execute each step of the continuous automatic focusing control method, and a computer-readable readable storage medium storing the control program The purpose is to provide.

  The compound-eye camera of the present invention is a compound-eye camera having at least two first imaging units and a second imaging unit, and is continuously focused from the time when the first imaging unit performs focus control and focuses. In addition, when the lens position of the second imaging unit is shifted from the in-focus state to either the front or the rear by a predetermined amount, the data amount from the first imaging unit and the data amount from the second imaging unit are Based on the correlation, the lens driving direction of the first image pickup unit is determined and focus control is performed, or a focus data processing unit that does not perform the focus control is provided, and thereby the above-described object is achieved. Is done.

  Preferably, the focus data processing unit in the compound-eye camera of the present invention includes a data amount change detecting unit that detects whether or not the data amount of the predetermined subject area from the first imaging unit has changed, and the data amount change A data amount correlation detecting means for detecting a correlation between the data amount from the first imaging unit and the data amount from the second imaging unit when the detecting unit detects that the data amount has changed; and the data amount correlation Lens driving direction determining means for determining the lens driving direction of the first imaging unit from the correlation detected by the detecting means.

  Further preferably, the focus data processing unit in the compound eye camera of the present invention controls the lens drive so that the lens position of the second imaging unit is shifted by a predetermined amount from the in-focus state to either the front or the rear by a predetermined amount. The camera further includes offset means for outputting a control signal to the unit and moving the lens position by the lens driving member.

  Further preferably, the focus data processing unit in the compound-eye camera of the present invention searches for a position where the focus evaluation value is maximized by sequentially moving the lens position in the lens driving direction determined by the lens driving direction determining means, AF processing means for setting the local maximum position to the in-focus position is provided.

  Further preferably, the data amount correlation detecting means in the compound eye camera of the present invention is such that the data amount of the first imaging unit is decreased and the data amount of the second imaging unit is increased as the correlation of the data amount. When the lens is detected, the lens driving direction determination means determines the lens driving direction in the same direction as the direction in which the lens position is shifted by the second imaging unit.

  Further preferably, the data amount correlation detecting means in the compound eye camera of the present invention is such that the data amount of the first imaging unit is reduced and the data amount of the second imaging unit is also reduced as the correlation of the data amount. When the lens driving direction is detected, the lens driving direction determination unit determines the lens driving direction in the direction opposite to the direction in which the lens position is shifted by the second imaging unit.

  Still preferably, in a compound eye camera according to the present invention, the data amount correlation detecting means changes the data amount of the first imaging unit and the data amount of the second imaging unit at the same rate as the correlation of the data amount. When this is detected, the data amount correlation detecting unit determines that the focus is not deviated, and the lens driving direction determining process by the lens driving direction determining unit is not performed, and the data amount change by the data amount change detecting unit is performed. Return to the detection process.

  The continuous automatic focusing control method of the present invention is a continuous automatic focusing control method using a compound eye camera having at least two first imaging units and second imaging units, wherein the focus data processing unit includes the first imaging unit. When continuously focusing from the time when the focus control is performed by the unit, the lens position of the second imaging unit is shifted from the focused state either forward or backward by a predetermined amount, Based on the correlation between the amount of data from the first imaging unit and the amount of data from the second imaging unit, the lens driving direction of the first imaging unit is determined and focus control is performed, or the focus control is performed It has a focus data processing step that is not performed, whereby the above object is achieved.

  Preferably, in the data processing step for focus in the continuous automatic focusing control method of the present invention, the data amount change detecting unit detects whether or not the data amount of the predetermined subject area from the first imaging unit has changed. When the data amount change detection step and the data amount correlation detection unit detect that the data amount has changed in the data amount change detection step, the data amount from the first imaging unit and the data from the second imaging unit A data amount correlation detecting step for detecting a correlation between the amounts, and a lens driving direction determining step in which the lens driving direction determining means determines the lens driving direction of the first imaging unit from the correlation detected in the data amount correlation detecting step. And have.

  Further preferably, in the focusing data processing step in the continuous automatic focusing control method of the present invention, the offset means sets the lens position of the second imaging unit from a focused state either forward or backward by a predetermined amount. An offset process is further included in which a control signal is output to the lens drive control unit so as to be shifted by a fixed amount, and the lens position is moved by the lens drive member.

  Further preferably, in the focus data processing step in the continuous automatic focusing control method of the present invention, the AF processing means sequentially moves the lens position in the lens driving direction determined in the lens driving direction determination step, thereby evaluating the focus evaluation value. Is searched for a position where the local maximum is, and an AF processing step is performed in which the local maximum position is set as a focus position.

  Further preferably, in the data amount correlation detecting step in the continuous automatic focusing control method of the present invention, as the data amount correlation, the data amount correlation detecting means reduces the data amount of the first imaging unit, When it is detected that the data amount of the second image pickup unit has increased, the lens drive direction determination step is configured such that the lens drive direction determination unit has a lens in the same direction as the direction in which the lens position is shifted by the second image pickup unit. Determine the drive direction.

  Further preferably, in the data amount correlation detecting step in the continuous automatic focusing control method of the present invention, as the data amount correlation, the data amount correlation detecting means reduces the data amount of the first imaging unit, When it is detected that the data amount of the second imaging unit has also decreased, the lens driving direction determination step is performed in a direction opposite to the direction in which the lens driving direction determination unit shifts the lens position in the second imaging unit. Determine the lens driving direction.

  Further preferably, in the data amount correlation detecting step in the continuous automatic focusing control method of the present invention, the data amount correlation detecting means uses the data amount of the first imaging unit and the second amount as the correlation of the data amount. When it is detected that the data amount of the imaging unit has changed at the same rate, the data amount correlation detection unit determines that the focus is not shifted, and performs lens driving direction determination processing by the lens driving direction determination unit. First, the process returns to the data amount change detection process by the data amount change detection means.

  The control program according to the present invention describes a processing procedure for causing a computer to execute each step of the continuous automatic focusing control method according to the present invention, thereby achieving the above object.

  The readable storage medium of the present invention is a computer-readable storage medium storing the control program of the present invention, thereby achieving the above object.

  With the above configuration, the operation of the present invention will be described below.

  In the present invention, in a compound eye camera having at least two first imaging units and second imaging units, the first imaging unit performs focus control and continuously focuses from the point of focus. Based on the correlation between the amount of data from the first imaging unit and the amount of data from the second imaging unit, with the lens position of the two imaging units shifted from the focused state to either the front or the rear by a predetermined amount, A focus data processing unit that determines the lens driving direction of the first imaging unit and performs focus control or does not perform focus control is provided.

  This allows focus control by determining the lens drive direction during continuous AF or does not perform focus control, so unnecessary lens scanning can be reduced, so when shooting using continuous AF in monocular mode In addition, the AF response can be improved, and the image quality can be improved.

  As described above, according to the present invention, since the lens driving direction is determined during continuous AF and focus control is performed or focus control is not performed, continuous lens AF is performed in monocular mode in order to reduce unnecessary lens scanning. When shooting is performed, the AF response can be improved (the AF focusing speed can be improved), and the image quality can be improved. It also leads to a reduction in out of focus frames.

BRIEF DESCRIPTION OF THE DRAWINGS It is a block diagram which shows the principal part structural example of the compound eye camera in Embodiment 1 of this invention, Comprising: (a) is a block diagram for demonstrating AF process in the case of obtaining a stereo image with a compound eye, (b) is It is a block diagram for demonstrating AF process in the case of obtaining an image with a single eye. FIG. 2 is a block diagram illustrating a configuration example of a main part of a focus data processing unit in the compound eye camera of FIG. 1. 6 is a flowchart for explaining AF processing when the compound eye camera of FIG. 1 is used with a single eye. It is a block diagram which shows the principal part structural example of the conventional compound eye camera currently disclosed by patent document 1. FIG. It is a block diagram for demonstrating the AF process in the conventional compound eye camera of FIG.

  Hereinafter, Embodiment 1 of the compound eye camera of the present invention will be described in detail with reference to the drawings.

(Embodiment 1)
FIG. 1 is a block diagram illustrating a configuration example of a main part of a compound eye camera according to Embodiment 1 of the present invention. FIG. 1A is a block diagram for explaining AF processing when a stereoscopic image is obtained with a compound eye. FIG. 6B is a block diagram for explaining AF processing when an image is obtained with a single eye.

  1A and 1B, the compound eye camera 1 of the first embodiment has at least two first imaging units 11 and 12 on the left and right sides, and these first imaging unit 11 and The second imaging unit 12 includes a lens 2, a lens driving motor 3 that moves the position of the lens 2, a motor control unit 4 that controls the driving direction and driving amount of the lens driving motor 3, and the subsequent stage of the lens 2. An image sensor 5 which is disposed on the side and receives the subject light transmitted through the lens 2 and images the subject light, and a signal processing unit 6 which obtains a color image signal by performing various signal processing on each imaging signal from the image sensor 5 have.

  The lens 2 includes a diaphragm and a mechanical shutter in addition to a zoom lens and a focus lens (not shown).

  The image sensor 5 is arranged on the rear side of the lens 2 and receives the subject light transmitted through the lens 2 to capture the subject light. A large number of light receiving portions (not shown) are two-dimensionally arranged in a matrix in the matrix direction on the light receiving surface of the image sensor 5, and red (R) and green (G) (not shown) corresponding to each light receiving portion. , Blue (B) primary color filters are arranged in a predetermined color arrangement, for example, a Bayer arrangement.

  The signal processing unit 6 is provided in an analog signal processing unit including a correlated double sampling circuit (CDS), a clamp processing circuit, an automatic gain control circuit (AGC) and an A / D converter, and a subsequent stage of the analog signal processing unit, Digital signal processing unit such as color interpolation, white balance and γ correction for obtaining color image signal, and analog signal processing unit are provided in the subsequent stage, compression / decompression processing unit, integration unit and external memory control unit, analog signal processing A focus data processing unit 61 that is provided in a subsequent stage and performs focus control continuously, and a memory control unit 62 that is provided in a subsequent stage of the analog signal processing unit and stores or reads out an image signal in an image memory; Each process with the display control unit 63 that is provided in the subsequent stage of the analog signal processing unit and controls the display of the image signal on the display screen of the display unit The has.

  When obtaining a stereoscopic image with compound eyes, the focus data processing unit 61 individually performs continuous focusing control on each of the first imaging unit 11 and the second imaging unit 12 as shown in FIG. In other words, the focus data processing unit 61 in each signal processing unit 6 of the first imaging unit 11 and the second imaging unit 12 respectively controls the motor control unit 4 to move the lens 2 sequentially by the lens driving motor 3. Then, continuous focus control is performed to obtain the focus position from the image signal captured by the image sensor 5 at this time. In addition, when obtaining an image with a single eye, the focus data processing unit 61 continuously focuses from the time point when the first imaging unit 11 performs focus control to focus, as shown in FIG. When focusing, the amount of data obtained from the first imaging unit 11 and the second imaging in a state where the lens position of the second imaging unit 12 is shifted from the in-focus state to either the front or the rear by a predetermined amount D. Based on the correlation with the data amount obtained from the unit 12, the lens drive direction of the first image pickup unit 11 is determined, and focus control is performed with the lens position having the largest data amount as the focal point.

  That is, in the continuous focus control process using the compound eye camera 1 of the first embodiment, as shown in FIG. 1B, the compound eye camera 1 is used as a monocular camera (here, the first imaging unit 11 is used). In addition, when shooting with continuous AF, the lens position of the second image pickup unit 12 on the unused side is set to the same position as the lens position of the first image pickup unit 11 in which the focus on the use side is focused. The first imaging unit 11 that captures and displays an image is continuously set by setting the lens position shifted forward or backward by a predetermined amount D from the lens position in focus, and comparing the data amounts for each focus. Since it is possible to easily predict the moving direction of the lens 2 for the next focusing by AF processing, it is not necessary to move the lens 2 in an unnecessary direction as in the prior art, and the focusing time is greatly increased. So that the can be shortened.

  Further, in the continuous focusing control process using the compound eye camera 1 according to the first embodiment, as shown in FIG. 1B, the main camera (here, the first imaging unit 11 is used) that performs monocular imaging using continuous AF. The second image pickup unit 12 other than the use) is used as an auxiliary, and is intentionally more than the focus point of the main camera (here, the first image pickup unit 11 is used) (the first time focus is performed by the conventional method). The lens position is moved and controlled so that the focal point is shifted to the far side or the near side (forward or backward) by the fixed amount D, and the amount of focus data of both cameras (the first imaging unit 11 and the second imaging unit 12) is subjected to signal processing. Monitoring is performed by the focus data processing unit 61 of the unit 6. By correlating both data amounts, it is possible to perform the prediction of the true / false of the focus shift and the shift direction.

  Here, the compound eye camera 1 of Embodiment 1 and the continuous automatic focusing control method using the same will be described in more detail with reference to FIGS. 1B and 2.

  The focus data processing unit 61 of the first imaging unit 11 is configured by a CPU (Central Processing Unit), and is based on a control program read from the ROM 616 into the RAM 617 at startup and various data used for the control program. The absolute value data in the focus area such as a human face as the subject area is integrated to obtain a focus evaluation value (the higher the contrast, the larger the data amount, the value corresponding to the data amount), and the motor control unit 4 is controlled. Then, the lens position is sequentially moved by the lens driving motor 3 to search for a position where the focus evaluation value becomes maximum, and the lens 2 is moved to the maximum position (focusing position) by the motor control unit 4 and the lens driving motor 3. AF processing means 611 for moving the lens and the lens position of the second image pickup unit 12 from the in-focus state to either the front or the rear by a predetermined amount D. An offset unit 612 that outputs a control signal to the lens drive control unit so as to shift by D and moves the lens position by the lens drive member, and detects whether the data amount of the predetermined subject area from the first imaging unit 11 has changed. When the data amount change detecting unit 613 and the data amount change detecting unit 613 detect that the data amount has changed, the correlation between the data amount from the first imaging unit 11 and the data amount from the second imaging unit 12 is obtained. A data amount correlation detecting unit 614 to be detected, and a lens driving direction determining unit 615 for determining the lens driving direction of the first imaging unit 11 from the correlation detected by the data amount correlation detecting unit 614, and the AF processing unit 611 Then, the lens position is sequentially moved in the lens driving direction determined by the lens driving direction determination means 615 to search for a position where the focus evaluation value is maximized. A large position as the focusing position.

  When the data amount correlation detection unit 614 detects that the data amount of the first imaging unit 11 is decreased and the data amount of the second imaging unit 12 is increased as the correlation of the data amount, the lens driving direction determination unit 615 determines the lens driving direction in the same direction as the direction in which the second imaging unit 12 has shifted the lens position by a predetermined amount D.

  Further, when the data amount correlation detection unit 614 detects that the data amount of the first imaging unit 11 is decreased and the data amount of the second imaging unit 12 is also decreased as the correlation of the data amount, the lens driving direction The determination unit 615 determines the lens driving direction in the direction opposite to the direction in which the second imaging unit 12 has shifted the lens position by a predetermined amount D.

  Furthermore, when the data amount correlation detection unit 614 detects that the data amount of the first imaging unit 11 and the data amount of the second imaging unit 12 have changed at the same rate as the correlation of the data amount, the data amount The correlation detection unit 614 determines that the focus is not deviated, and does not perform the lens drive direction determination process by the lens drive direction determination unit 615, and returns to the data amount change detection process by the data amount change detection unit 613. Is done.

  The continuous automatic focusing control method using the compound eye camera 1 is based on the control program in the RAM 617 and various data used for the AF processing means 611 in the focus area such as a human face as a predetermined subject area. The absolute value data is integrated to obtain a focus evaluation value, and the motor control unit 4 is controlled to sequentially move the lens position by the lens driving motor 3 to search for a position where the focus evaluation value becomes maximum, and the maximum position. The AF processing step of moving the lens 2 by the motor control unit 4 and the lens driving motor 3 to (focus position) and the offset means 612 moves the lens position of the second imaging unit 12 forward or backward by a predetermined amount D. A control signal is output to the lens drive control unit so that the lens position is moved by the lens drive member so as to be shifted by a predetermined amount D from the in-focus state. A data amount change detecting step in which the data amount change detecting unit 613 detects whether the data amount of the predetermined subject area from the first imaging unit 11 has changed; and a data amount correlation detecting unit 614 A data amount correlation detection step of detecting a correlation between the data amount from the first image pickup unit 11 and the data amount from the second image pickup unit 12 when the change detection unit 613 detects that the data amount has changed; A lens driving direction determining step in which the direction determining unit 615 determines the lens driving direction of the first imaging unit 11 from the correlation detected by the data amount correlation detecting unit 614, and the AF processing unit 611 is in the lens driving direction determining unit 615. An AF processing step in which the lens position is sequentially moved in the determined lens driving direction to search for a position where the focus evaluation value becomes maximum, and the maximum position is set as an in-focus position; It has.

  In the data amount correlation detecting step, when the data amount correlation detecting unit 614 detects that the data amount of the first imaging unit 11 is decreased and the data amount of the second imaging unit 12 is increased as the correlation of the data amount. In the lens driving direction determination step, the lens driving direction determination unit 615 determines the lens driving direction in the same direction as the direction in which the lens position is shifted by the predetermined amount D by the second imaging unit 12.

  Further, in the data amount correlation detection step, as the data amount correlation, the data amount correlation detection unit 614 detects that the data amount of the first imaging unit 11 has decreased and the data amount of the second imaging unit 12 has also decreased. In this case, in the lens driving direction determination step, the lens driving direction determination unit 615 determines the lens driving direction in a direction opposite to the direction in which the second imaging unit 12 has shifted the lens position by the predetermined amount D.

  Further, in the data amount correlation detecting step, as the data amount correlation, the data amount correlation detecting means 614 detects that the data amount of the first image pickup unit 11 and the data amount of the second image pickup unit 12 have changed at the same rate. In this case, the data amount correlation detection unit 614 determines that the focus is not shifted, and does not perform the lens drive direction determination process by the lens drive direction determination unit 615 but performs the data amount change detection process by the data amount change detection unit 613. Return.

  Hereinafter, the continuous automatic focusing operation of the compound eye camera 1 with the above configuration will be described.

  FIG. 3 is a flowchart for explaining AF processing when the compound eye camera 1 of FIG. 1 is used with a single eye.

  As shown in FIG. 3, first, in step S1, the AF processing unit 611 of the first imaging unit 11 performs AF processing, integrates absolute value data in a focus area such as a human face, and the focus evaluation value (contrast is reduced). The higher the value is, the larger the data amount is, and a value corresponding to the data amount is obtained. The position where the focus evaluation value is maximized is searched, and the motors of the first imaging unit 11 and the second imaging unit 12 are located at the maximum position. The lens 2 is moved by the control unit 4 and each lens driving motor 3 to perform in-focus imaging. A color image signal obtained by subjecting the image pickup signal to various signal processing by the signal processing unit 6 is stored in an image memory (not shown) via the memory control unit 62, and a display unit (not shown) via the display control unit 63. Display control on the display screen.

  Next, in step S2, the offset unit 612 performs an offset process. That is, the lens position is shifted by intentionally moving the position of the lens 2 of the second imaging unit 12 forward or backward in a predetermined direction by a predetermined amount D.

  Subsequently, in step S3, the data amount change detection unit 613 determines whether or not AF (autofocus) has been lost depending on whether or not the data amount has changed. The data amount change determination process in step S3 is repeated until AF is removed. If the data amount has changed in step S3 (YES), the process proceeds to the data amount correlation detection process in the next step S4. It should be noted that an appropriate value is determined in advance by an experiment to determine how much the data amount changes to determine that AF is lost.

  Thereafter, if the data amount has changed in step S3 (YES), the data amount correlation detecting means 614 performs the data amount correlation detection processing by looking at the correlation of the data amount in step S4, and according to the correlation detection processing result, In step S5, the lens drive direction determination unit 615 determines the lens drive direction of the first imaging unit 11 for AF processing from the correlation detected by the data amount correlation detection unit 614.

  That is, the data amount correlation detection unit 614 has the data amount correlation by the AF processing unit 611 of the first imaging unit 11 decreased and the data amount by the AF processing unit 611 of the second imaging unit 12 increased as the data amount correlation. In this case, the lens driving direction determination unit 615 determines the lens driving direction in the same direction as the direction in which the lens 2 is shifted by the second imaging unit 12, and the lens 2 of the first imaging unit 11 is moved to the motor of the first imaging unit 11. The control unit 4 and the lens driving motor 3 are moved to a position where the focus evaluation value (data amount) is maximized in the determined lens driving direction to perform in-focus imaging.

  Further, the data amount correlation detecting unit 614 reduces the data amount by the AF processing unit 611 of the first imaging unit 11 and the data amount by the AF processing unit 611 of the second imaging unit 12 as the correlation of the data amount. In this case, the lens driving direction determination unit 615 determines the lens driving direction in the direction opposite to the direction in which the lens 2 is shifted by the second imaging unit 12, and the lens 2 of the first imaging unit 11 is connected to the first imaging unit 11. The motor control unit 4 and the lens driving motor 3 are moved to a position where the focus evaluation value (data amount) is maximized in the determined lens driving direction to perform in-focus imaging.

  Furthermore, when the data amount by the AF processing unit 611 of the first imaging unit 11 and the data amount by the AF processing unit 611 of the second imaging unit 12 change (increase or decrease) at the same rate as the correlation of the data amount Therefore, the data amount correlation detection unit 614 determines that the focus is not shifted, and does not perform the lens drive direction determination process by the lens drive direction determination unit 615, and returns to the data amount change detection process by the data amount change detection unit 613. . For example, when the focus area, such as a person's face, changes and the area increases, the amount of data increases even if focus is achieved. Conversely, if the focus area changes and its area decreases, the amount of data decreases even if focus is achieved. In these cases, the amount of data changes (increases or decreases) at the same rate.

  As described above, according to the first embodiment, the lens position of the second imaging unit 12 is set to the predetermined amount D when the first imaging unit 11 performs focus control and continuously focuses from the point of focus. Based on the correlation between the amount of data from the first imaging unit 11 and the amount of data from the second imaging unit 12 in a state shifted from the in-focus state to either the front or the rear, the lens drive of the first imaging unit 11 A focus data processing unit 61 that determines the direction and performs focus control is provided.

  Thus, in the continuous automatic focusing control method using the compound eye camera 1 of the first embodiment, the focus position of the image display camera is simultaneously performed with the AF performed by the main camera for image display (first imaging unit 11). On the other hand, the auxiliary camera (second image pickup unit 12) in which the lens position is aligned with the position where the focus is intentionally shifted is also picking up an image. By monitoring the amount of data for both the main and sub focus and taking the correlation, it is possible to predict the direction of the focus shift when it is assumed that the focus shift is true or false. The focus can be focused in the shortest time. As described above, when shooting using continuous AF in the monocular mode, the AF response can be improved and the image quality can be improved.

  In short, in the continuous AF, when the AF is removed, it is possible to predict the perspective direction (front side or front side movement) of the lens 2 to be moved next. Since it is not necessary to sweep the lens 2 in the reverse direction, the time until focusing is shortened, and the AF response can be improved. Further, since it is not necessary to sweep the lens 2 in the reverse direction, unnecessary defocus frames until focusing can be reduced, and the image quality can be improved. Furthermore, even when the focus data amount changes due to the subject moving out of the focus area, the correlation of the change in the data amount of each camera (the first image pickup unit 11 and the second image pickup unit 12) is correlated. It can also be determined whether or not to refocus by looking.

  Furthermore, the continuous automatic focusing control method in the compound eye camera 1 of Embodiment 1 is a change in the control method without changing the system configuration in one use mode when the compound eye camera 1 is used as a monocular camera. It is possible to provide an image in which image quality deterioration is suppressed, and application to a 3D camera having a compound eye is expected.

  In the first embodiment, each of the light passing through the lens 2 is subjected to photoelectric conversion by the image sensor 5 and signal processing is performed so that it can be displayed as an image. During the signal processing, there is a focus data processing unit 61 for adjusting the focus. The data is processed and fed back to the lens position via the motor control unit 4 and the lens driving motor 3. In FIG. 1, the processing is completed inside the system. However, a system may be used in which the focus data is output outside the system, the determination is performed outside, and the motor is controlled.

  As mentioned above, although this invention has been illustrated using preferable Embodiment 1 of this invention, this invention should not be limited and limited to this Embodiment 1. It is understood that the scope of the present invention should be construed only by the claims. It is understood that those skilled in the art can implement an equivalent range based on the description of the present invention and the common general technical knowledge from the description of specific preferred embodiments 1 to 3 of the present invention. Patents, patent applications, and documents cited herein should be incorporated by reference in their entirety, as if the contents themselves were specifically described herein. Understood.

  The present invention has a compound eye camera that has at least two imaging optical systems on the left and right and enables stereoscopic imaging, a continuous automatic focusing control method using the same, and each step of the continuous automatic focusing control method is executed on a computer In the field of a control program in which a processing procedure for performing the control is described and a computer-readable readable storage medium storing the control program, the AF response is improved when shooting using continuous AF in the monocular mode. Image quality can be improved.

DESCRIPTION OF SYMBOLS 1 Compound eye camera 11 1st imaging part 12 2nd imaging part 2 Lens 3 Lens drive motor (Lens drive member)
4 Motor controller (Lens drive controller)
DESCRIPTION OF SYMBOLS 5 Image sensor 6 Signal processing part 61 Focusing data processing part 611 AF processing means 612 Offset means 613 Data amount change detection means 614 Data amount correlation detection means 615 Lens drive direction determination means 62 Memory control part 63 Display control part D Predetermined amount

Claims (16)

In a compound eye camera having at least two first imaging units and second imaging units,
When continuously focusing from the time point when focus control is performed by the first image pickup unit, the lens position of the second image pickup unit is shifted from the focus state either forward or backward by a predetermined amount. In this state, based on the correlation between the data amount from the first imaging unit and the data amount from the second imaging unit, the lens driving direction of the first imaging unit is determined and focus control is performed, or A compound-eye camera having a focus data processing unit that does not perform the focus control.   The focus data processing unit detects data amount change detecting means for detecting whether or not the data amount of the predetermined subject area from the first imaging unit has changed, and detects that the data amount has changed by the data amount change detecting means. The data amount correlation detecting means for detecting the correlation between the data amount from the first imaging unit and the data amount from the second imaging unit, and the correlation detected by the data amount correlation detecting means. The compound-eye camera according to claim 1, further comprising: a lens driving direction determination unit that determines a lens driving direction of one imaging unit.   The focus data processing unit outputs a control signal to the lens drive control unit to drive the lens so that the lens position of the second imaging unit is shifted by a predetermined amount from the in-focus state either forward or backward by a predetermined amount. The compound eye camera according to claim 1, further comprising offset means for moving the lens position by a member.   The focus data processing unit sequentially moves the lens position in the lens driving direction determined by the lens driving direction determination unit to search for a position where the focus evaluation value becomes a maximum, and uses the maximum position as an in-focus position. The compound eye camera according to claim 2, further comprising a processing unit.   When the data amount correlation detection unit detects that the data amount of the first imaging unit is decreased and the data amount of the second imaging unit is increased as the correlation of the data amount, the lens driving direction The compound eye camera according to claim 2, wherein the determination unit determines the lens driving direction in the same direction as the direction in which the lens position is shifted in the second imaging unit.   When the data amount correlation detecting unit detects that the data amount of the first imaging unit is decreased and the data amount of the second imaging unit is also decreased as the correlation of the data amount, the lens driving direction The compound-eye camera according to claim 2, wherein the determination unit determines the lens driving direction in a direction opposite to a direction in which the lens position is shifted by the second imaging unit.   When the data amount correlation detection unit detects that the data amount of the first imaging unit and the data amount of the second imaging unit change at the same rate as the correlation of the data amount, the data amount The correlation detection unit determines that the focus is not deviated, and does not perform the lens drive direction determination process by the lens drive direction determination unit, and returns to the data amount change detection process by the data amount change detection unit. Compound eye camera. In a continuous automatic focusing control method using a compound eye camera having at least two first imaging units and second imaging units,
When the focus data processing unit continuously focuses from the time point when the first imaging unit performs focus control, the lens position of the second imaging unit is either forward or backward by a predetermined amount. The lens drive direction of the first image pickup unit is determined based on the correlation between the data amount from the first image pickup unit and the data amount from the second image pickup unit in a state shifted from the in-focus state. A continuous automatic focusing control method including a focus data processing step in which focus control is performed or the focus control is not performed.   In the focus data processing step, the data amount change detecting unit detects whether the data amount of the predetermined subject area from the first imaging unit has changed, and the data amount correlation detecting unit includes: A data amount correlation detecting step of detecting a correlation between the data amount from the first imaging unit and the data amount from the second imaging unit when it is detected that the data amount has changed in the data amount change detecting step; The continuous automatic focusing control according to claim 8, further comprising: a lens driving direction determination unit that determines a lens driving direction of the first imaging unit from the correlation detected in the data amount correlation detection step. Method.   In the focus data processing step, the offset means outputs a control signal to the lens drive control unit so that the lens position of the second imaging unit is shifted by a predetermined amount from the in-focus state to either the front or rear by a predetermined amount. The continuous automatic focusing control method according to claim 8, further comprising an offset step of moving the lens position by a lens driving member.   In the focus data processing step, the AF processing means sequentially moves the lens position in the lens driving direction determined in the lens driving direction determination step to search for a position where the focus evaluation value becomes maximum, and matches the maximum position. The continuous automatic focusing control method according to claim 9, further comprising an AF processing step for setting a focal position.   In the data amount correlation detecting step, the data amount correlation detecting means detects that the data amount of the first imaging unit has decreased and the data amount of the second imaging unit has increased as the correlation of the data amount. In this case, the lens driving direction determining step determines the lens driving direction in the same direction as the direction in which the lens driving direction is shifted by the second imaging unit. Focus control method.   In the data amount correlation detecting step, as the data amount correlation, the data amount correlation detecting unit detects that the data amount of the first imaging unit is decreased and the data amount of the second imaging unit is also decreased. In this case, the lens driving direction determination step determines the lens driving direction in a direction opposite to the direction in which the lens driving direction determination unit has shifted the lens position in the second imaging unit. Focus control method.   In the data amount correlation detecting step, the data amount correlation detecting means determines that the data amount of the first imaging unit and the data amount of the second imaging unit have changed at the same rate as the correlation of the data amount. When detected, the data amount correlation detection means determines that the focus is not shifted, and does not perform the lens driving direction determination processing by the lens driving direction determination means, but the data amount change detection processing by the data amount change detection means. The continuous automatic focusing control method according to claim 9, wherein   A control program in which a processing procedure for causing a computer to execute each step of the continuous automatic focusing control method according to claim 8 is described.   A computer-readable storage medium in which the control program according to claim 15 is stored.

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