JP5655750B2 - Video imaging device - Google Patents

Description

  The present invention relates to a video imaging device such as a stereoscopic video that images a subject with a plurality of imaging units.

  3D image systems that allow viewers to perceive 3D images with parallax left-eye video and right-eye video are in the spotlight. On the other hand, a camera having a plurality of image pickup units and having a function of picking up a stereoscopic image has been put into practical use, and the stereoscopic image is spreading widely and generally. As a focus control method for a stereoscopic video imaging apparatus, for example, in Patent Document 1, two images having left and right information of a subject are captured by two cameras, a zoom lens and a short focus lens, and a first video signal and a second video are captured. In a stereoscopic video camera that outputs a signal, it is disclosed that focus control is performed by a zoom lens based on a distance from the camera to a subject.

JP-A-9-37299

  However, in the stereoscopic video imaging apparatus disclosed in Patent Document 1, there may be a case where focusing cannot be performed when a subject to be imaged is captured on only one video.

  In view of such a problem, an object of the present invention is to provide a video imaging apparatus capable of appropriately performing focus control depending on the position of a subject to be imaged.

In order to solve the above-described problems, the present invention provides the following image pickup devices (a) and (b).
(A) a first imaging unit (102L) for imaging, a second imaging unit (102R) for imaging, a subject identifying unit (104) for identifying a subject, the identified subject and the first A distance detection unit (104) that detects a subject distance that is a distance between the first imaging unit and the second imaging unit; and the first imaging unit and the first imaging unit based on the distance information detected by the distance detection unit. And a position control unit (106) for controlling the focus position of each of the two imaging units. The first imaging unit captures images within a predetermined range and the second imaging unit. When the subject is located within a predetermined range of the second video, the distance detection unit detects the subject distance based on the first video or the second video, and the predetermined distance of the first video is determined. The image of the subject is located within the range of When the subject is not located within a predetermined range of the second video, the distance detection unit detects the subject distance based on the first video, and the distance within the predetermined range of the first video When the subject is not located and the subject is located within a predetermined range of the second video, the distance detection unit detects the subject distance based on the second video. apparatus.
(B) When the video of the subject is located within a predetermined range of the first video and within a predetermined range of the second video, the distance detection unit detects the subject distance based on the first video Switching between detection of the subject and the second video based on the position of the subject video, and the distance detection unit detecting the subject distance based on the first video The position of the subject when switching to a state of detecting the subject based on a second video and the state of detecting the subject distance based on the second video based on the first video The stereoscopic video imaging apparatus according to (a), wherein the position of the subject when switching to the state of detecting the subject is set to a different position.

  According to the video imaging apparatus of the present invention, it is possible to appropriately perform focus control depending on the position of the subject to be imaged.

It is a block diagram which shows the structure of a video imaging device. It is a figure for demonstrating operation | movement of a video imaging device. It is another figure for demonstrating operation | movement of a video imaging device.

  FIG. 1 shows a configuration of a video imaging apparatus according to the present invention. The video imaging apparatus 100 includes a left imaging unit 102L, a right imaging unit 102R, a subject distance detection unit 104, a focus adjustment unit 106, a left video processing unit 108L, a right video processing unit 108R, a left and right video synthesis unit 110, a compression unit 112, a recording Part 114.

  The left imaging unit 102L captures an image for the left eye and sends an imaging signal to the subject distance detection unit 104 and the left image processing unit 108L. The right imaging unit 102R captures the right-eye video and sends an imaging signal to the subject distance detection unit 104 and the right video processing unit 108R. The subject distance detection unit 104 extracts a high-frequency component of the subject video signal obtained from the imaging signal, detects the lens position where the high-frequency component is the largest as the best focus point, and focuses the detection result as the best focus point signal. This is sent to the adjustment unit 106. In addition, the subject distance detection unit 104 is separately arranged around the imaging unit when the high-frequency component of the subject video signal obtained from the imaging signal cannot be accurately detected when the subject to be imaged or the background is dark. A measurement unit that irradiates infrared rays in the imaging direction and measures the distance of the subject from the response may be provided, and the distance measurement signal may be sent to the focus adjustment unit 106. This focus best point signal or distance measurement signal is hereinafter also referred to as subject distance information. The subject distance detection unit 104 has a face detection engine that detects a human face, for example, which is a subject as a subject according to the present invention, or an engine that detects a car license plate. It also has a function of detecting a subject from the left-eye video signal and the right-eye video signal.

  The focus adjustment unit 106 adjusts the focus of the left imaging unit 102L and the right imaging unit 102R to optimum values based on the subject distance information received from the subject distance detection unit 104. As a result, the stereoscopic video imaging apparatus 100 is set to an appropriate focus according to the subject distance. The left video processing unit 108L performs signal processing on the left-eye video signal received from the left imaging unit 102L and sends the signal to the left and right video synthesis unit 110. The right video processing unit 108R performs signal processing on the right-eye video signal received from the right imaging unit 102R and sends the signal to the left and right video synthesis unit 110. The left and right video synthesizing unit 110 synthesizes the received left-eye video signal and right-eye video signal, and sends the synthesized stereoscopic video signal to the compression unit 112. The compression unit 112 compresses the received stereoscopic video signal and sends it to the recording unit 114. The recording unit 114 includes a semiconductor memory such as a flash memory, an HDD, and the like, and records the received compressed signal. The video imaging apparatus 100 combines the left-eye video signal and the right-eye video signal via an interface (not shown), or transmits the left-eye video signal and the right-eye video signal to the outside.

The subject distance detection operation will be described with reference to FIGS.
FIG. 2A shows a state where a moving subject is imaged by the left imaging unit 102L and the right imaging unit 102R. A circular figure represents a subject, and the subject position moves in the order of a, b, and c. The ranges indicated as the left imaging unit imaging range and the right imaging unit imaging range indicate ranges captured by the imaging units. FIGS. 2B to 2G show images obtained by imaging the subjects at the respective positions a, b, and c with the respective imaging units. 2B, 2D, and 2F show images captured by the left imaging unit 102L, and FIGS. 2C, 2E, and 2G show images captured by the right imaging unit 102R. 2B and 2C show images when the subject is at the position a, and FIGS. 2D and 2E show images when the subject is at the position b, and FIG. ) And (g) show images when the subject is at the position c.

  When the subject is at the position a, as shown in FIGS. 2B and 2C, the subject video is located within the range of the video imaged by the left imaging unit 102L and the video imaged by the right imaging unit 102R. Not within range. Therefore, at this time, a high-frequency signal can be obtained from the video signal from the left imaging unit 102L due to the presence of the subject, or subject distance information can be obtained from the infrared measurement result. Can do. When the subject is at the position b, as shown in FIGS. 2D and 2E, the subject video is located within the range of the video imaged by the left imaging unit 102L and the video imaged by the right imaging unit 102R. Yes. Accordingly, at this time, the distance of the subject can be similarly detected from both the video signal from the left imaging unit 102L and the video signal from the right imaging unit 102R. When the subject is at the position c, as shown in FIGS. 2F and 2G, the subject image is not located within the range of the image captured by the left imaging unit 102L, and is captured by the right imaging unit 102R. Is within the range of the selected video. Accordingly, at this time, the distance of the subject can be similarly detected from the video signal from the right imaging unit 102R.

As described above, depending on the position of the subject, there may be a subject image for both of the images captured by the left and right imaging units, but there may be a subject image only in one of the images. When the subject video is within a predetermined range of one of the images captured by the left and right imaging units and not within the predetermined range of the other video, the subject distance detection unit 104 has the subject video within the predetermined range. The subject distance is detected based on the video signal of the other side. When the subject video is within a predetermined range of both the images taken by the left and right imaging units, the subject distance detection unit 104 is either a video signal taken by the left imaging unit or a video taken by the right imaging unit. The subject distance is detected based on the above.
When the subject moves to positions a, b, and c as shown in FIG. 2, the subject distance detection unit 104 first converts the video signal for detecting the subject distance into a video signal captured by the left imaging unit. Is switched to the video signal imaged by the right imaging unit immediately before the image captured by the left imaging unit passes the vicinity of the center of the image and immediately before deviating from the imaging range of the left imaging unit. The switching position is appropriately changed depending on the position of the subject and the position, moving direction, and moving speed of the subject.

Specifically, subject distance detection is performed from the video signal imaged by the left imaging unit and the video signal imaged by the right imaging unit, and the focus is adjusted based on the subject distance information that can be obtained accurately and stably. For example, it is determined whether the subject is in the vicinity of the center position in the captured image or in the peripheral position, and the subject is particularly positioned near the right (inner) boundary in the image captured by the left imaging unit. When switching to the subject distance detection from the video signal imaged by the right imaging unit, when the subject is located near the left (inside) boundary in the video imaged by the right imaging unit, the left imaging unit Control is performed so as to switch to subject distance detection from the video signal picked up in step (b).
In addition to grasping the current position of the subject, the position of the subject in the previous video signal is stored in time, and the moving direction and moving speed information are obtained by comparing with the position, and the moving direction and Based on the moving speed information, it may be controlled which of the imaging units switches to subject distance detection from a video signal captured by the imaging unit.

  Further, it may be determined based on distance information in the focus direction of the position of the subject whether to switch to subject distance detection from the video signal captured by the left or right imaging unit. For example, the current distance information and the previous distance information in advance are stored, and the subject distance information from the video signal imaged by either imaging unit does not change so much, and the left and right are almost the same value. , Control is performed so that either one of them is changed, and when only one of them is suddenly changed, control is performed so that the distance information of the one not changed is adopted.

  As in FIG. 2, FIG. 3 schematically shows a state in which a moving subject is imaged by each imaging unit and an image in which the subject at each position is imaged by each imaging unit. In FIG. 2, the subject has moved from left to right at positions a, b, and c, whereas in FIG. 3, the subject has moved from right to left to positions a, b, and c. In this case, the subject distance detection unit 104 first uses the video signal for detecting the subject distance as a video signal captured by the right imaging unit, and the subject video passes through the vicinity of the center of the video captured by the right imaging unit and captures the right image. The video signal is switched to the video signal captured by the left imaging unit immediately before the imaging range of the unit is out of range. The switching position is appropriately changed depending on the position of the subject and the position, moving direction, and moving speed of the subject.

Specifically, in the same manner as described above, the subject distance is detected from the video signal captured by the left imaging unit and the video signal captured by the right imaging unit, and the focus is adjusted based on the distance information that can be obtained accurately and stably. To do. For example, it is determined whether the subject is in the vicinity of the center position in the captured image or in the peripheral position, and the subject is particularly positioned near the right (inner) boundary in the image captured by the left imaging unit. When switching to the subject distance detection from the video signal imaged by the right imaging unit, when the subject is located near the left (inside) boundary in the video imaged by the right imaging unit, the left imaging unit Control is performed so as to switch to subject distance detection from the video signal picked up in step (b).
In addition to grasping the current position of the subject, the position of the subject in the previous video signal is stored in time, and the moving direction and moving speed information are obtained by comparing with the position, and the moving direction and Based on the moving speed information, it may be controlled which of the imaging units switches to subject distance detection from a video signal captured by the imaging unit.

  Further, it may be determined based on distance information in the focus direction of the position of the subject whether to switch to subject distance detection from the video signal captured by the left or right imaging unit. For example, the current distance information and the previous distance information in advance are stored, and the subject distance information from the video signal imaged by either imaging unit does not change so much, and the left and right are almost the same value. , Control is performed so that either one of them is changed, and when only one of them is suddenly changed, control is performed so that the distance information of the one not changed is adopted.

As described above, appropriate object distance detection and focus control are performed by switching the image for the object distance detection unit 104 to detect the object distance according to the object position, the object position, the moving direction, and the moving speed. be able to. In addition, the subject distance detection unit 104 sets the position in the subject video as a reference for switching the video for detecting the subject distance to a position in the video that differs depending on the moving direction of the subject, so that If the subject stays near the position in the video to be switched or moves back and forth near the position in the video to be switched, unnecessary power consumption due to frequent switching is provided. Consumption can be prevented.
Since the subject distance detection from the video signal captured by the left imaging unit and the video signal captured by the right imaging unit has a slight increase in power consumption, the shooting mode can be selectively switched, for example, Only a shooting mode such as sports with intense movement may be enabled.
It should be noted that the present invention is not limited to the case of shooting a stereoscopic video by imaging the same subject with the right and left imaging units as in a stereoscopic video shooting device, and can be applied. For example, in the imaging range of the imaging unit on one side, when a car or a ball crosses in front of the subject for a short time, the lens cover is momentarily applied to the imaging unit on one side, and the subject is in some areas The same applies to a case where imaging cannot be performed.

DESCRIPTION OF SYMBOLS 100 Stereoscopic imaging device 102L Left imaging part 102R Right imaging part 104 Subject distance detection part 106 Focus adjustment part 108L Left video processing part 108R Right video processing part 110 Left-right video synthetic | combination part 112 Compression part 114 Recording part

Claims (2)

A first imaging unit for imaging;
A second imaging unit for imaging;
A subject identifying unit for identifying a subject;
A distance detection unit that detects a subject distance that is a distance between the identified subject and the first imaging unit and the second imaging unit;
A position control unit that controls a focus position of each of the first imaging unit and the second imaging unit based on distance information detected by the distance detection unit;
When the subject is located within a predetermined range of the first video imaged by the first imaging unit and within a predetermined range of the second video imaged by the second imaging unit, the distance detection unit is Detecting the subject distance based on the first video or the second video;
When the image of the subject is located within a predetermined range of the first video and the subject is not located within a predetermined range of the second video, the distance detection unit is based on the first video Detecting the subject distance,
When the subject is not located within a predetermined range of the first video and the subject is located within a predetermined range of the second video, the distance detection unit is configured to perform the distance detection based on the second video. A video imaging apparatus characterized by detecting a subject distance. When the subject video is located within a predetermined range of the first video and within a predetermined range of the second video, the distance detection unit detects a subject distance based on the first video. Or whether to detect based on the second video, depending on the position of the video of the subject,
The position of the subject when the distance detection unit switches from a state in which the subject distance is detected based on the first video to a state in which the subject is detected based on the second video; The position of the subject when switching from the state in which the subject distance is detected based on the second video to the state in which the subject is detected based on the first video is set to a different position. Item 2. The video imaging apparatus according to Item 1.

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