JP2018007055A - Digital camera, image processing apparatus, and wide-angle lens - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique for improving the impression of boundary region of a circular image and the outer image of outer circumference, even in the image data captured using a wide angle lens having an angular field of view of 180 degrees or more.SOLUTION: A digital camera (1) including a wide angle lens (2) having an angular field of view of 180 degrees or more, a digital image pickup device (3) for capturing the image data, and image processing means (4) for processing the image data captured by the digital image pickup device, and outputting or saving in a predetermined image format, is further provided with boundary area image generation means (22) for generating a boundary area image in the boundary area of a circular image incident on the digital image pickup device (3) from the wide angle lens (2), and the outer image of outer circumference.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a wide-angle lens having a viewing angle of 180 degrees or more, a digital camera and an image processing apparatus using the wide-angle lens, and particularly to processing of a boundary region between a circular image captured by a super-wide-angle lens and an outer peripheral image. This is the technology.

  In recent years, the application of VR (virtual reality) technology has progressed, and accordingly, the demand for photographing the surroundings with an ultra-wide angle image has increased. The applicants of the present application have also provided ultra wide-angle lenses with viewing angles of 220, 250 degrees, 270 degrees, and 280 degrees. Images taken using such an ultra-wide-angle lens can be digitally imaged and converted to a viewing angle close to that of human vision, and then reproduced on-site by scrolling on a computer screen. it can.

For example, when taking a picture in the horizontal direction using a lens with a viewing angle of 220 degrees, an image taken with an ultra-wide-angle lens is recorded as a circular image by a digital image sensor in a digital camera. When this image is displayed by 360 degree VR technology, the 140 degree part on the back side is positioned outside the image, and no light is incident on the digital image sensor, so that the image data is blackened.
When the wide angle lens is photographed vertically upward, an image of 360 degrees around the horizon can be photographed. If the viewing angle is 200 degrees, the ground side is photographed by 10 degrees from the horizontal direction, and the ground side is in a blackened state.

  As a related prior art, Patent Document 1 relates to a technique for irradiating light from an LED light source to a peripheral portion of a field of view of a wide-angle imaging lens. When a wide-angle lens having a viewing angle of about 180 degrees is used, the peripheral portion of the field of view The structure using the LED for cameras which can irradiate and the light guide lens of a rotary body shape is disclosed.

  Further, Patent Document 2 discloses a solid-state imaging device and an imaging system that can capture bright images up to the periphery even when a single-lens reflex imaging lens that is used by exchanging various lenses is used in a digital camera or the like. An apparatus is disclosed, and it can be avoided that a peripheral portion becomes dark at the time of photographing.

  In Patent Document 3, a single image sensor has an image circle necessary for the diagonal fisheye system on the telephoto side and a light beam having a desired shooting angle of view or more is effective for the circumferential fisheye system on the wide angle side. A zoom lens and an image pickup apparatus that can shield light are disclosed. In this technique, a fish-eye zoom lens including a light shielding member that shields an end portion is proposed.

JP2013-15211A JP2012-094601 JP 2014-137383 A

  In the above prior art, Patent Documents 1 and 2 are techniques for capturing a bright image so that the amount of light in the peripheral image is not short, that is, Patent Document 3 is provided with a light-shielding member at the end, and the end is clear. It can be said that it is a technique for classifying. Not only in Patent Document 3, but with an ultra-wide-angle lens, the outer portion of the circular image is extremely bad, but the design of the lens also requires a larger internal lens, so the incident portion that becomes the end Is well known to include a light shielding member to make it difficult to see the aberration at the periphery of the circular image.

However, when an image with an ultra-wide angle is processed and scrolled as described above, the edge may suddenly fall out of black, which may cause a sense of discomfort or be confused with an image defect.
The present invention was created in view of such problems of the prior art, and even in image data captured using a wide-angle lens with a viewing angle of 180 degrees or more, a circular image and an outer peripheral image position are included. An object is to provide a technique for improving the impression of the boundary region.

In order to solve the above problems, the present invention provides the following means.
That is, the invention according to claim 1 processes a wide-angle lens having a viewing angle of 180 degrees or more, a digital image sensor that captures image data of a moving image or a still image, image data captured by the digital image sensor, and performs predetermined processing. A digital camera having image processing means for outputting or saving in an image format, and generates a boundary region image in a boundary region between a circular image incident on a digital image sensor from a wide-angle lens and an outer peripheral image. A boundary area image generation means is provided.

  The invention according to claim 2 provides a configuration in which the boundary region image generation means forms a transition image in which the brightness changes at least in steps.

  In the invention according to claim 3, the boundary region image generation means generates a predetermined image external position image at the image external position, and the boundary region image generation means transitions from the circular image to the image external position image. A transition image can be formed.

  The invention according to claim 4 is characterized in that, as the boundary region image generating means, the wide-angle lens is provided with a lens-side filter member that blocks the light beam near the wide-angle end in a stepwise manner to lower the brightness.

  The invention according to claim 5 is characterized in that, as the boundary region image generation means, the digital image sensor includes an image sensor side filter member that gradually reduces the brightness of incident light in the boundary region.

  The invention according to claim 6 provides a configuration in which the image processing means adds a predetermined additional image to at least one of the boundary region and the image external position.

  According to a seventh aspect of the present invention, the boundary region image generating means in the digital camera is provided in an independent computer image processing apparatus. That is, an image processing device for processing image data captured by a wide-angle lens having a viewing angle of 180 degrees or more, and a circular image incident on the digital image sensor from the wide-angle lens and an outer image position on the outer periphery. Image processing means for generating a border area image in the border area, and the image processing means forms a transition image whose brightness changes stepwise at least, or forms a predetermined image outside image at the image outside position. A transition image that is generated and transitions from the circular image to the external image is formed.

  The invention according to claim 8 is a wide-angle lens having a viewing angle of 180 degrees or more for use in a digital camera, and a boundary region between a circular image incident on the digital image sensor from the wide-angle lens and an outer peripheral image position. A wide-angle lens is characterized in that a transition image in which the brightness changes at least in steps is formed.

The present invention has the following effects by the above configuration.
That is, by providing the boundary area image generating means in the digital camera, the boundary area image can be generated in the boundary area between the circular image incident on the digital image sensor and the outer peripheral image. Impression can be improved.
In particular, by forming a transition image in which the brightness changes stepwise in the boundary region, it is easy to understand that it is an end portion, and contributes to the provision of an image without a sense of incongruity.

  In addition, the boundary region image generation means generates a predetermined image external position image at the image external position, and forms a transition image that transitions from the circular image to the image external position image, thereby further inserting an image without a sense of incongruity It is also possible to insert desired information.

  A configuration that adds a predetermined additional image to at least one of the boundary area and the image external position is provided in combination with the boundary area image to further reduce the uncomfortable feeling of the boundary area and provide additional information to the user can do.

  The present invention is not limited to a digital camera, and can be provided as an interchangeable lens for a digital camera.

It is explanatory drawing of Example 1 of the digital camera which concerns on this invention. It is explanatory drawing of Example 2 of the digital camera which concerns on this invention. It is explanatory drawing which shows the relationship between a viewing angle and a boundary area | region. It is an image which shows the aspect of the boundary area | region which concerns on this invention. It is an image which shows the aspect (Example 1) of the boundary area | region which concerns on this invention. It is an image which shows the additional image (Example 3) which concerns on this invention. It is an image which shows the aspect (Example 4) of the boundary area | region which concerns on this invention. 1 is a configuration diagram of an image processing apparatus according to the present invention.

Hereinafter, embodiments of the present invention will be described based on examples shown in the drawings. The embodiment is not limited to the following.
Example 1
FIG. 1 is an explanatory diagram of Embodiment 1 of a digital camera according to the present invention. In the present invention, the digital camera (1) processes a wide-angle lens (2) having a viewing angle of 180 degrees or more, a digital imaging device (3) for imaging image data, and image data captured by the digital imaging device. And an image processing circuit (4) which is an image processing means for outputting or saving in a predetermined image format.

Such a digital imaging device is well known as a CCD image sensor or a CMOS image sensor, and the type of the device is not limited in the present invention. The image processing circuit is also mounted on a known digital camera or smartphone, and a known technique can be used as appropriate.
The image data targeted by the present invention may be either a moving image or a still image. In the case of a moving image, a known VR moving image technology, for example, a technology related to Google Cardboard (registered trademark) of Google (registered trademark), YouTube ( 360 degree moving image technology in (registered trademark) can be used.

  As shown in the figure, when a wide-angle lens (2) having a viewing angle of, for example, 220 degrees is used, the incident light (20) to the wide-angle lens (2) is refracted according to the lens design within the wide-angle lens (2). To reach the digital imaging device (3). Incident light (21) from the inside, for example from a direction of 180 degrees, is incident on the center side of the digital imaging device (3). The illustrated optical path is simplified for the sake of explanation, and does not accurately display the optical path in the lens. Needless to say, the optical path can be appropriately designed.

  FIG. 3 is an explanatory diagram showing the relationship between the viewing angle and the boundary region. 3A shows a case where the viewing angle of the wide-angle lens 2 is 180 degrees, FIG. 3B shows a case where the viewing angle is 220 degrees, and FIG. 3C shows a case where the viewing angle is 250 degrees. In the figure, the images (50) (51) (52) on the upper side are the front side (object side) of the wide-angle lens (2). The lower image external positions (53) (54) (55) are on the back side. Due to the aberration of the lens, a boundary region (56) having a large color blur or distortion between the images (50) (51) (52) within the viewing angle of the lens and the image external positions (53) (54) (55). ) (57) (58).

  FIG. 4 is an image showing an aspect of the boundary region according to the present invention. As is well known, an image acquired with a digital imaging device using a wide-angle lens with a very large viewing angle shows a circular image (image circle) in the center, and there is no incident light around it. Place. The boundary region described in FIG. 3 appears in an annular shape on the outer peripheral portion of the circular image.

  In the prior art, by providing a light blocking member for blocking the light flux in the boundary region, the boundary region is not captured as shown in FIG. Therefore, the boundary between the circular image (60) and the image external position (61) is clearly separated. Such a conventional configuration is considered to have a purpose of giving a clear impression to an image obtained by not showing an unclear portion of an image.

  However, when an image such as a VR is created using a wide-angle lens as in the present invention, it is common to convert to a viewing angle close to human vision by image processing, and scroll to browse. If the border between the circular image (60) and the image external position (61) is suddenly blackened as in the case of the scroll, there is a sudden impression when scrolling, and there is a problem of giving the viewer unnaturalness. . In addition, since it suddenly becomes black, it is easy to misunderstand image defects, and there is also a problem in terms of ease of use.

  Therefore, as shown in FIG. 4B, in the present invention, boundary region image generating means for generating a boundary region image (62) in the boundary region between the circular image (60) and the outer peripheral image position (61). It is provided with.

  As the boundary region image, in this embodiment, a gradation (transition image) is formed in which the brightness changes stepwise from the circular image (60) toward the external image position (61). In the figure, blurring is performed so as to gradually change to black toward the image external position (61). As described above, the VR image is displayed by enlarging and converting a small part of the main image to an image close to the human viewing angle, so that even when scrolling to the end, it may be the end by gradation. It is easy to understand and can reduce discomfort.

When the gradation is set as the boundary region image (62), the transition image is not limited to blur, but may be a transition image by increasing black dots in a dot pattern, for example. (A) and (b) of FIG. 5 are display examples using dots of different modes.
The boundary region image (62) of the present invention is intended to naturally recognize that it is the edge of the image, and therefore any image or pattern can be used.
The image external position does not necessarily need to be black, and may be a white or transparent image. In that case, you may use the transition image which changes so that the brightness may become bright in steps.

As the boundary region image generating means, in this embodiment, as shown in FIG. 1, the wide-angle lens (2) is provided with a lens-side filter member (22) that gradually blocks the light beam near the wide-angle end to lower the brightness.
The lens-side filter member (22) is a member whose transmittance decreases in the circumferential direction, thereby realizing the transition image by stepping the light flux in the outer portion of the effective image.

  By applying a predetermined pattern to the lens-side filter member (22), the pattern of the boundary region image (62) can be realized. The lens-side filter member (22) is not limited to black, and may be given any color, for example, brown, green that matches the color of the ground, blue that matches the color of the sky, or the like. Furthermore, you may use the material which has the frequency selectivity of a light ray for the lens side filter member (22).

  In principle, the lens-side filter member (22) is provided in an annular shape so as to cover the outer portion of the circular image (60). However, the lens-side filter member (22) may cover a part of the boundary region or change the mode depending on the part. . For example, a configuration may be adopted in which only the portions on the left and right sides are used as the above transition image and the upper and lower portions are shielded from light as in the conventional case. The left and right sides and the lower side may be brown and the upper side may be blue.

(Example 2)
As another embodiment of the boundary region image generating means, as shown in FIG. 2, the image pickup device side filter member (30) for gradually decreasing the brightness of incident light in the boundary region can be provided in the digital image pickup device (3). . The image sensor side filter member (30) is provided at the boundary portion of the image connected on the digital image sensor (3), and is not limited to being in close contact with the digital image sensor (3), but corresponding to the digital image sensor (3). As long as it is provided, the distance may be some distance away.

  The image sensor side filter member (30) is also a member whose transmittance decreases in the circumferential direction of the formed circular image (60), thereby blocking the light flux in the outer portion of the effective image stepwise. The transition image can be realized.

  Moreover, the pattern of the said border area image (62) is also realizable by attaching | subjecting a predetermined pattern to the image pick-up element side filter member (30). The image pickup element side filter member (30) is not limited to black, and may be given any color, for example, brown, green matching the ground color, blue matching the sky color, or the like. Furthermore, you may use the material which has the frequency selectivity of a light ray for the image pick-up element side filter member (30).

  The imaging element side filter member (30) may also cover a part of the boundary region or change the mode depending on the part. For example, a configuration may be adopted in which only the portions on the left and right sides are used as the above transition image and the upper and lower portions are shielded from light as in the conventional case. The left and right sides and the lower side may be brown and the upper side may be blue.

In the above embodiment, the transition image is generated only in the vicinity of the boundary region between the circular image (60) and the external image position (61). The transition image may be extended to the inside.
For example, a transition image according to the present invention may be used in a range of 5%, 10%, 15%, and 20% inside the viewing angle. Although this portion can be visually recognized as an image in the super-wide-angle lens, the image quality may be deteriorated, and the present invention can be applied to connect the line of sight to the outside of the image without a sense of incongruity.

(Example 3)
In the present invention, as the processing of the image processing circuit (4), a predetermined additional image can be added to at least one of the boundary region image (62) and the image external position (61).
FIG. 6 is an image showing an additional image according to the present invention.

As a first example of the additional image, a character or a pattern, for example, a company name (70) can be added as an additional image so as to overlap the boundary region image (62). By using a border area that cannot be used as an image, it is easy to identify the edge when scrolling and displaying a VR image, and the image creator can include information such as attributes. Can do.
In the present invention, when a character or a pattern is added to the boundary region as described above, the boundary region image (62) itself can be used.

  As a second example of the additional image, a character (71) or a photograph (72) can be added to the image external position (61). The image external position (61) is a part resulting from the difference between the shape of the digital image sensor (3) and the shape of the circular image (60), and is not originally used as an image area. In the present invention, an image space can be used effectively by adding an additional image to the image external position (61), and the viewer can also enjoy watching the image external position (61).

The character (71) can be added by deforming the character in the same manner as the distortion of the image (60) so that the character (71) can be easily read when the VR image is enlarged or converted.
The additional image may be a two-dimensional barcode, a three-dimensional barcode, etc. in addition to characters and photographs. The bar code can include link information to a home page, or can include contact information, information related to shooting parameters at the time of shooting, and the like using a three-dimensional bar code.

The additional image may be an advertisement for promoting a product or a company. Further, the additional image may be a lottery so that it can be determined whether the image is hit or missed depending on the image.
As the additional image, an arbitrary image such as a graphic image, a drawing, a table, or a graph can be used in addition to characters and photographs. It may also be a video. In the case of a moving image, a moving image that progresses simultaneously with a timeline in a circular image may be used, or a moving image may be added to a circular image of a still image.

Example 4
In the present invention, as the processing of the image processing circuit (4), a predetermined image external position image can be generated at the image external position (61). In this embodiment, the image processing circuit (4) forms a transition image for transitioning from a circular image to an image external level image.
As an example of the image external position image, as shown in FIG. 7, an image related to the circular image (60), for example, an image obtained by extending a part of the circular image (60) is displayed as the image external position (61). Insert as image (80).

Here, the external image (80) may be generated using the circular image (60) itself, or a general landscape may be used. Further, an image in the circular image (60) may be acquired, and an image similar to the image may be selected by a known selection technique to generate the image external position image (80).
The external image (80) does not necessarily need to be identified when viewed visually, and when it appears on the outer periphery of the field of view, it seems to continue from the circular image (60) without any sense of incongruity. The purpose is to be felt.

The image processing circuit (4) generates the transition image (81) so that the circular image (60) and the image external level image (80) continuously transition. The transition image (81) can be processed so that the circular image (60) and the image external position image (80) are continuous by a known image composition technique. Moreover, after making a transition from a circular image (60) to a predetermined color such as black once, it may be changed to the image external level image (80) again.
The additional image may be further added to the external image (80).

In the present invention, the processing in the image processing circuit (4) and the like can be performed in a known personal computer or server device.
FIG. 8 is a block diagram of an image processing apparatus (9) according to the present invention. The image processing apparatus (9) has a configuration of a known personal computer or the like. In the figure, only the CPU (90), the card reading unit (91), and the monitor (92) are shown, but other configurations are provided. Can do.

  An image is taken using a digital camera according to the present invention or provided with a wide-angle lens having a viewing angle of 180 degrees or more, which is generally distributed, and stored in a known memory card or the like. By reading this memory card with the card reading unit (91), the image processing unit (901) can process it.

As the first processing of the image processing unit (901), a transition image can be generated in the boundary region between the circular image (60) and the image external position (61) in the input image. The transition image may be configured such that at least the brightness changes stepwise from the circular image (60) to the image external position (61) as in the second embodiment, or in the image external position as in the fourth embodiment. A configuration may be employed in which a predetermined image external position image is generated and a transition image for transitioning from a circular image to the image external position image is formed.
Further, an additional image can be added as shown in the third embodiment.

  As described above, in the transition image, the image selection unit (902) generates an image similar to the circular image (60) in order to continue the circular image (60) to the external image (81) without a sense of incongruity. The image may be selected by a selection technique, and the image outside image (80) may be generated in the image processing unit (901) and stored in the memory card.

The image processing apparatus (9) may be provided with a monitor (92) so that the processed image can be browsed.
When the image processing device (9) is provided as a server, the image data received through the communication network may be processed by the image processing unit (901) and transmitted through the processed image data communication network.

  The present invention can also be provided as a wide-angle lens having a viewing angle of 180 degrees or more for use in a digital camera having the above-described features. Thereby, the boundary area image having the effect of the present invention can be used for each interchangeable lens.

According to the present invention, not only a 360-degree VR image but also a VR display using an image with a viewing angle that is not so large can provide a good viewing angle effect. For example, in recent years, a head-mounted display for displaying a VR image has become widespread, but a portion with a viewing angle of 200 degrees or more corresponds to a portion that is shaken or viewed with a horizontal eye. If the image of this part is suddenly interrupted and becomes black or a different color, it gives a sense of incongruity. In this regard, in the present invention, such a sense of incongruity can be greatly reduced by generating a transition image.
In addition, the line of sight can be naturally induced even when information or advertisement is displayed outside the image, so that these effects can be enhanced.

  Also, many images are not suitable for 360-degree images. For example, there may be a case where one side is a wall or there is no need to take a picture up to the back of the audience seat such as a soccer ground. In the VR technology, a viewing angle of 200 degrees or more is sufficient for sitting and viewing, and the present invention is particularly suitable for displaying such an image without a sense of incongruity.

DESCRIPTION OF SYMBOLS 1 Digital camera 2 Wide angle lens 3 Digital image sensor 4 Image processing circuit 20 Incident light (220 degree | times)
21 Incident light (180 degrees)
22 Lens side filter member

Claims (8)

A wide-angle lens with a viewing angle of 180 degrees or more;
A digital image sensor that captures video or still image data;
An image processing means that processes image data captured by the digital image sensor and outputs or stores the image data in a predetermined image format,
A digital camera comprising boundary region image generation means for generating a boundary region image in a boundary region between a circular image incident on the digital image sensor from the wide-angle lens and an outer peripheral image. The boundary region image generating means is
The digital camera according to claim 1, wherein at least a transition image whose brightness changes stepwise is formed. The boundary region image generating means is
Generating a predetermined image external position image at the image external position;
The digital camera according to claim 1, wherein a transition image for transitioning from the circular image to the external image is formed. As the boundary region image generation means,
The digital camera according to claim 2, wherein the wide-angle lens includes a lens-side filter member that gradually blocks a light beam near the wide-angle end to lower brightness. As the boundary region image generation means,
The digital camera according to claim 2, wherein the digital image sensor includes an image sensor side filter member that gradually reduces the brightness of incident light in the boundary region. The digital camera according to any one of claims 1 to 5, wherein the image processing means adds a predetermined additional image to at least one of the boundary region and the image external position. An image processing apparatus for processing image data shot with a wide-angle lens having a viewing angle of 180 degrees or more,
Image processing means for generating a boundary region image in a boundary region between a circular image incident on the digital image sensor from the wide-angle lens and the outer peripheral image;
The image processing means forms at least a transition image whose brightness changes stepwise, or generates a predetermined image external image at the image external position, and transitions from the circular image to the image external image. An image processing apparatus characterized in that a transition image is formed. A wide-angle lens with a viewing angle of 180 degrees or more for use in a digital camera,
A wide-angle lens, wherein a transition image in which brightness changes at least in a stepwise manner is formed in a boundary region between a circular image incident on a digital image sensor from the wide-angle lens and an outer peripheral image.

Images