CN106873301A - Based on the system and method that array camera is imaged to remote aperture rear - Google Patents

Abstract

The invention discloses a system and method for imaging the back of a long-distance small hole based on an array camera. The array camera is used to take multi-angle shots of the scene behind the aperture with a limited field of view, and the multi-angle images are collected, and then the aperture image is extracted, Affine transformation projection and image matching can obtain an image of a larger field of view behind a small aperture; it can take multi-angle shots of the rear scene through a small aperture from a certain distance, and obtain a panoramic image behind the hole. If this imaging system is thoroughly studied and fully used in the military field, it will bring great convenience to our army.

Description

System and method for imaging rear of long-distance small hole based on array camera

technical field

The invention belongs to the field of photoelectric imaging, and in particular relates to a system and method for imaging the rear of a long-distance small hole based on an array camera.

Background technique

The light field is the parametric representation of the four-dimensional optical radiation field that contains both position and direction information in space. The acquisition of light field data provides a lot of new development space for computational parametric imaging.

Light field imaging records the four-dimensional position and direction information of light radiation during propagation, which has two more degrees of freedom than the traditional imaging method that only records two-dimensional, so that richer graphic information can be obtained in the image reconstruction process.

In light field imaging, there are two main ways to obtain the light field:

microlens array. It refers to inserting a microlens array at the primary image plane of an ordinary imaging system, and the light recorded by each microlens element corresponds to the scene image at the same position and different viewing angles, thereby obtaining a four-dimensional light field.

array camera. It refers to the method of reconstructing light field data by simultaneously capturing a series of scene images with slightly different perspectives through a certain arrangement of cameras in space.

In the military field, for example, when rescuing hostages, sometimes it is necessary to spy on the room where the hostages are located through a narrow aperture from a long distance, so as to determine an effective rescue plan. At the same time, in order to ensure safety, it is necessary to observe at a relatively long distance. In this case, if you directly observe with a telescope, it is difficult to conduct a comprehensive observation of the indoor situation due to the limitation of the aperture range. At this time, the principle of the present invention can be used to take a series of scene images of different viewing angles through a group of array cameras, and stitch and process the series of images, so as to obtain a relatively complete scene image in the room observed through the aperture, and obtain a comprehensive view. Indoor information.

Contents of the invention

The purpose of the present invention is to solve the problem that the long-distance micro-aperture limits the observation field of view. The array camera is used to take multi-angle shots of the scene behind the limited aperture of the field of view, collect multi-angle images, and then extract and affine transform the projection through the aperture image. Match the image to obtain an image of a larger field of view behind the small aperture.

The purpose of the present invention is achieved through the following technical solutions.

A system for imaging the scene behind a long-distance small hole based on an array camera. The array camera is aimed at the small hole, and each camera in the array camera performs imaging through the small hole; wherein, the distance from each array element camera to the small hole is the same , and the centerlines of the field of view of each array element camera intersect at one point.

Preferably, the array cameras are divided into five rows, and five cameras are arranged in each row.

Preferably, the small hole is a square of 5cm×5cm, and the array camera is 5m away from the small hole.

A method for imaging a scene behind a long-distance small hole based on an array camera, comprising the following steps:

S1. After the array cameras are placed, control each array camera to shoot the rear scene through the small aperture;

S2 processes each image collected by the camera, and extracts and obtains an effective aperture image captured by each camera;

S3. Define the image captured by the camera located at the center of the array as the central image, and define the images obtained by other cameras as the edge image;

S4. Using affine transformation, the edge image is projected onto the image plane where the center image is located; then the same feature points are extracted to match the edge image with the center image, and finally a complete mosaic panoramic image is obtained.

The present invention has following beneficial effects:

Aiming at the problem of long-distance micro-aperture limiting the observation field of view, such as the problem of spying on the hostage’s room through a narrow aperture at a long distance, the ordinary imaging system cannot solve it at all due to the limitation of the aperture range; the array camera in the present invention The system can take multi-angle shots of the rear scene through a small aperture from a certain distance to obtain a panoramic image behind the aperture. If this imaging system is thoroughly studied and fully used in the military field, it will bring great convenience to our army.

Description of drawings

Figure 1 is a schematic diagram of the arrangement principle of the array camera.

Fig. 2 is a simulation diagram of an array camera system for imaging the scene behind the hole through a long-distance small hole.

Fig. 3 is a simulation diagram of an imaging system for imaging the scene behind the hole through a small hole at a long distance.

Fig. 4 is an effective image captured by a camera in the array camera through a small hole.

Fig. 5 is an image formed by splicing effective images captured by all cameras in the array camera.

Fig. 6 is the experimental flow chart of the whole invention.

Among them, a-the intersection point of the centerline of the field of view of the camera, 1-camera, 2-support, 3-array camera system, 4-small hole.

detailed description

The present invention will be described in detail below with reference to the accompanying drawings and examples.

A system of the present invention based on an array camera for imaging a scene behind a long-distance small hole, as shown in FIG. 3 , the entire imaging system includes an array camera system 3 and a long-distance small hole 4 .

As shown in FIG. 2 , an array camera consists of several rows of cameras 1 . In order to perfectly coincide the adjacent fields of view in the array camera 1 used, and to avoid the problem that the fields of view cannot be perfectly spliced due to the different sizes and resolutions of objects in the fields of view of different cameras 1, the The principle that needs to be observed in the process of determining the overall placement of the camera 1 is that the distance from each camera 1 to the hole 4 is as consistent as possible, and each image has a close magnification, thereby ensuring the splicing quality of the output image.

Another key point is that, as shown in Figure 1, if placed according to the placement method mentioned above, the centerlines of the fields of view of these cameras 1 must intersect at one point (point a in Figure 1), which is The position of the center of the sphere where the lens center of each camera 1 is located. Obviously, the distance from this point to the center of each camera 1 lens is the same.

In the imaging system 3 of the present invention, the array camera 1 is divided into five rows, 5 in each row, supported by the bracket 2 . The small hole 4 is a square of 5cm×5cm, and the array camera is 5m away from the small hole, and each camera collects images of the rear scene through the small hole 4 .

The present invention provides a method for imaging the back of the small hole 4 based on an array camera. As shown in FIG. Shooting of the scene behind. Each camera 1 will capture an image. Since only the part of each image that passes through the tiny aperture is a valid image, it is necessary to process the image collected by each camera to extract the effective aperture captured by each camera 1. image. Relative to the camera 1 in the center, the edge images obtained by other cameras 1 have a certain angular offset relative to the images collected by the center camera 1, and it is necessary to use affine transformation to project the edge images onto the image plane where the center image is located. After the above operations are completed, the same feature points are extracted to match the edge image with the center image, and finally a complete stitched panoramic image is obtained. The flowchart is shown in Figure 6.

As shown in Figure 4, the obtained 25 effective images with overlapping parts are stitched together to obtain a complete scene image, as shown in Figure 5.

To sum up, the above are only preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (4)

1. it is a kind of based on array camera to the system of remote aperture rear Scenery Imaging, it is characterized by：Array camera is directed at institute Aperture is stated, each camera is imaged respectively through aperture in array camera；Wherein, distance phase of each array element camera to aperture Together, and the field of view center line of each array element camera meets at a bit.

2. it is as claimed in claim 1 it is a kind of based on array camera to the system of remote aperture rear Scenery Imaging, its feature It is that 5 cameras are put in five rows of the array camera point, often arrangement.

3. it is as claimed in claim 2 it is a kind of based on array camera to the system of remote aperture rear Scenery Imaging, its feature It is that aperture is the square of 5cm × 5cm, and array camera is apart from aperture 5m.

4. a kind of imaging method based on system described in claim 1, it is characterised in that comprise the following steps：

S1, be well placed array camera after, control each array camera to be shot to rear scenery through the small-bore；

S2 is processed each image that camera is gathered, and is extracted and is obtained the effective subaperture image that each camera shoots；

Image, the image definition that other cameras are obtained centered on S3, the image definition that will be shot positioned at array center's position camera It is edge image；

S4, edge image is projected to center image using affine transformation where image planes on；Then extracting same characteristic features point makes Edge image is matched with center image, finally obtains complete spliced panoramic image.