Imaging device, image processing apparatus, and image processing method

1. An imaging device, comprising:

at least six imagers, each including an imaging element configured to receive light incident through a lens having an angle of view of 180° or more; and

a casing on which at least six of the at least six imagers are arranged, the casing being a hexagonal column having eight surfaces and being configured such that each one of the imagers and another one of the imagers have optical axes substantially parallel to each other and have opposite incident directions of light on the optical axes, and each one of the imagers is arranged outside imageable ranges of the other imagers,

wherein the at least six imagers are configured to capture images in all three-dimensional direction, and the images in each direction are captured with three imagers among the at least six imagers.

2. The imaging device according to claim 1 , wherein eight of the imagers are arranged on the casing.

3. The imaging device according to claim 1 , wherein the imagers are arranged on only six surfaces from among the eight surfaces.

4. An image processing apparatus, comprising:

an acquirer configured to acquire captured images captured by at least four imagers, each including an imaging element configured to receive light incident through a lens having an angle of view of 180° or more, the imagers being arranged on a casing such that each one of the imagers and another one of the imagers have optical axes substantially parallel to each other and have opposite incident directions of light on the optical axes, and each one of the imagers is arranged outside imageable ranges of the other imagers; and

an image processor configured to generate a spherical distance image expressed by three-dimensional point-group information, based on the captured images acquired from all the imagers arranged on the casing, by extracting feature points in a first captured image of the captured images, and transforming the extracted feature points into a reference image obtained from a second captured image of the captured images,

wherein the first captured image and the second captured image are captured by two of the imagers arranged at two surfaces sharing an edge of the casing, respectively.

5. The image processing apparatus according to claim 4 , wherein the image processor further generates a spherical image in which each pixel is expressed by at least brightness information based on the captured images acquired from all the imagers arranged at the casing.

6. The image processing apparatus according to claim 5 , wherein the image processor combines a set of the captured images acquired from the two of the imagers arranged at two surfaces sharing an edge of the casing, and a set of the captured images acquired from two of the imagers arranged at the casing and having optical axes substantially parallel to each other and having opposite incident directions of light on the optical axes, and generates the spherical distance image and the spherical image in all three-dimensional directions.

7. The image processing apparatus according to claim 4 , wherein the acquirer acquires the captured image from each one of the imagers each including the imaging element configured to receive light incident through the lens having an angle of view of 180° or more.

8. The image processing apparatus of claim 4 , wherein the image processor is further configured to obtain the reference image by transforming the second captured image into an equidistant cylindrical image.

9. An image processing method, comprising:

acquiring captured images captured by at least four imagers, each including a lens with a total angle of view of 180° or more and an imaging element configured to receive light incident through the lens, the imagers being arranged on a casing such that each one of the imagers and another one of the imagers have optical axes substantially parallel to each other and have opposite incident directions of light on the optical axes, and each one of the imagers is arranged outside imageable ranges of the other imagers; and

generating a spherical distance image expressed by three-dimensional point-group information, based on the captured images acquired from all the imagers arranged on the casing, by extracting feature points in a first captured image of the captured images, and transforming the extracted feature points into a reference image obtained from a second captured image of the captured images,

wherein the first captured image and the second captured image are captured by two of the imagers arranged at two surfaces sharing an edge of the casing, respectively.

10. An imaging system, comprising:

the image processing apparatus of claim 4 ; and

an imaging device including the at least four imagers and the casing, wherein the casing is a cube having chamfered surfaces.