In photography, an omnidirectional camera (from "omni", meaning all), also known as 360-degree camera, is a camera having a field of view that covers approximately the entire sphere or at least a full circle in the horizontal plane. Omnidirectional cameras are important in areas where large visual field coverage is needed, such as in panoramic photography and robotics. [1]
A camera normally has a field of view that ranges from a few degrees to, at most, 180°. This means that it captures, at most, light falling onto the camera focal point through a hemisphere. In contrast, an ideal omnidirectional camera captures light from all directions falling onto the focal point, covering a full sphere. In practice, however, most omnidirectional cameras do not cover the entire sphere. Many cameras which are referred to as omnidirectional cover the full 360° along the equator of the sphere but exclude the top and bottom. In the case that they do cover the full sphere, the captured light rays do not intersect exactly in a single focal point.
Various techniques can be used to generate 360-degree images.
These models are used with a fisheye lens. The lens bends the angle of the shot to take a larger radius of the selected subject. It is not possible to take a complete 360-degree picture with this technique because there is always a dead angle directly behind the lens.
360-degree cameras with two lenses are probably the most common type, as they can accommodate a full 360-degree angle with two lenses facing each other. A camera takes pictures and videos with an angle of just over 180 degrees, e.g. 220 degrees. These are then converted into a 360-degree object using software. Problems are often caused by stitching errors that can happen at any given time. This means that an incorrect combination of the images can result in an unclean cut edge that is difficult or impossible to remove.
Depending on the application, manufacturers use more than two camera lenses to produce the images. One of the first cameras was Sony' Fourthview multihead camera [2] and the throwing camera, Panono. It has 36 cameras, which are triggered at the same time at the highest point, if the camera was thrown into the air. The more lenses are installed in the camera, the more difficult it becomes for the software to combine the individual images, however, the possible stitching problems are less with a good stitching.
Camera rigs are mostly used for the attachment of 6 conventional Actioncams. GoPro produced one of the first camera rigs. They are available in different versions and connect several single cameras. [3] The cameras are placed in this cube and record the surroundings in all directions.
If several "normal" cameras are combined in a network, one speaks of mosaic-based cameras. Each of these cameras records a small area of the environment. The individual images are then joined together like mosaic stones to form an omnidirectional overall image. The number of cameras to be used depends on the focal length of the lenses used. The smaller the focal length, the larger the angle of view and the fewer cameras are required.
Cars with omnidirectional camera include Nissan Qashqai, Volvo S90, Range Rover, Peugeot 3008 and Kia Stinger. [4]
Traditional approaches to panoramic photography mainly consists of stitching shots taken separately into a single, continuous image. The stitching of images, however, is computationally intensive (for example using the RANSAC iterative algorithm, commonly used to solve the correspondence problem), and depending upon the quality and consistency of the shots used, the resulting image might contain a number of deficiencies which impair the quality of the resulting image. In contrast, an omnidirectional camera can be used to create panoramic art in real time, without the need for post processing, and will typically give much better quality products.
In 2015 Facebook began rolling out omnidirectional videos where the user can view the video at any arbitrary camera angle around a 360-degree radius and limited tilt up-and-down angles.
In robotics, omnidirectional cameras are frequently used for visual odometry and to solve simultaneous localization and mapping (SLAM) problems visually. [5] [6] [7] [8] Due to its ability to capture a 360-degree view, better results can be obtained for optical flow and feature selection and matching.
360 cameras have become extremely popular within the real estate industry. With more and more homes being purchased sight-unseen, [9] 360 camera technology has offered a way for prospective home buyers to tour the home without having to be there in person. There are even 360 cameras on the market that have been created with real estate as the main subject in mind. [10]
Applications of omnidirectional cameras also include 3D reconstruction [11] and surveillance, when it is important to cover as large a visual field as possible. [12] Microsoft RoundTable was introduced in 2007 for videoconferencing, where all participants on one location can be in the same image.
Several implementations of omnidirectional (360-degree) cameras exist, including two opposing fisheye lens configurations and cameras with more than 30 separate lenses.
There have been fly-by-night companies that have produced prototypes and collected 'backers' on Kickstarter but have not delivered to end-users. [13]
More established 360-camera manufacturers currently actively producing and supporting hardware as of March 2020 include:
Frequent new models and quality improvements in consumer-marketed 360-cameras are blurring the line between the professional and consumer market. [24] [25]
A panorama is any wide-angle view or representation of a physical space, whether in painting, drawing, photography, film, seismic images, or 3D modeling. The word was coined in the 18th century by the English painter Robert Barker to describe his panoramic paintings of Edinburgh and London. The motion-picture term panning is derived from panorama.
In photography, angle of view (AOV) describes the angular extent of a given scene that is imaged by a camera. It is used interchangeably with the more general term field of view.
In photography and cinematography, a normal lens is a lens that reproduces a field of view that appears "natural" to a human observer. In contrast, depth compression and expansion with shorter or longer focal lengths introduces noticeable, and sometimes disturbing, distortion.
In photography and cinematography, a wide-angle lens is a lens covering a large angle of view. Conversely, its focal length is substantially smaller than that of a normal lens for a given film plane. This type of lens allows more of the scene to be included in the photograph, which is useful in architectural, interior, and landscape photography where the photographer may not be able to move farther from the scene to photograph it.
Panoramic photography is a technique of photography, using specialized equipment or software, that captures images with horizontally elongated fields of view. It is sometimes known as wide format photography. The term has also been applied to a photograph that is cropped to a relatively wide aspect ratio, like the familiar letterbox format in wide-screen video.
QuickTime VR is an image file format developed by Apple Inc. for QuickTime, and discontinued along with QuickTime 7. It allows the creation and viewing of VR photography, photographically captured panoramas, and the viewing of objects photographed from multiple angles. It functions as plugins for the QuickTime Player and for the QuickTime Web browser plugin.
A virtual tour is a simulation of an existing location, usually composed of a sequence of videos, still images or 360-degree images. It may also use other multimedia elements such as sound effects, music, narration, text and floor map. It is distinguished from the use of live television to affect tele-tourism.
Image stitching or photo stitching is the process of combining multiple photographic images with overlapping fields of view to produce a segmented panorama or high-resolution image. Commonly performed through the use of computer software, most approaches to image stitching require nearly exact overlaps between images and identical exposures to produce seamless results, although some stitching algorithms actually benefit from differently exposed images by doing high-dynamic-range imaging in regions of overlap. Some digital cameras can stitch their photos internally.
PTGui is a panorama photo stitching program for Windows and macOS developed by New House Internet Services BV. PTGui was created as a GUI frontend to Helmut Dersch's Panorama Tools. It features its own stitching and blending engine along with compatibility to Panorama Tools. PTGui supports telephoto, normal, wide angle and fisheye lenses to create partial cylindrical up to full spherical panoramas. PTGui can handle multiple rows of images.
Fulldome refers to immersive dome-based video display environments. The dome, horizontal or tilted, is filled with real-time (interactive) or pre-rendered (linear) computer animations, live capture images, or composited environments.
360-degree videos, also known as surround video, or immersive videos or spherical videos, are video recordings where a view in every direction is recorded at the same time, shot using an omnidirectional camera or a collection of cameras. The term 360x180 can be used to indicate 360° of azimuth and 180° from nadir to zenith. During playback on normal flat display the viewer has control of the viewing direction like a panorama. It can also be played on a display or projectors arranged in a sphere or some part of a sphere.
VR photography is the interactive viewing of panoramic photographs, generally encompassing a 360-degree circle or a spherical view. The results is known as VR photograph, 360-degree photo, photo sphere, or spherical photo, as well as interactive panorama or immersive panorama.
A panoramic tripod head is a piece of photographic equipment, mounted to a tripod, which allows photographers to shoot a sequence of images around the entrance pupil of a lens that can be used to produce a panorama. The primary function of the panoramic head is to precisely set the point of rotation about the entrance pupil for a given lens and focal length, eliminating parallax error.
A panorama portrait in photography and painting is the use of panoramic photography or imaging to convey a portrait of a person. It intends to be a bi-dimensional record of a 3D reality where the whole environment is emphasized and captured.
The Brenizer method, sometimes referred to as bokeh panorama or bokehrama, is a photographic technique characterized by the creation of a digital image exhibiting a shallow depth of field in tandem with a wide angle of view. Created by use of panoramic stitching techniques applied to portraiture, it was popularized by photographer Ryan Brenizer.
Omniview technology is a vehicle parking assistant technology that first was introduced in 2007 as the "Around View Monitor" option for the Nissan Elgrand and Infiniti EX. It is designed to assist drivers in monitoring their surroundings, for example, while parking a vehicle in a small space.
A 3D rig is a device for mounting two cameras together to one 3D-system in order to shoot stereoscopic films and images.
Panono is a spherical camera developed by the Berlin-based company Professional360 GmbH, formerly known as Panono GmbH. The camera captures full-spherical, 360° x 360° panoramic images with a resolution of 108 megapixels.
Arashi Vision Inc., doing business as Insta360, is a camera company headquartered in Shenzhen, Guangdong, with offices in Los Angeles, Tokyo and Berlin. It makes action cameras, 360-degree cameras, editing software for mobile and desktop and 180-3D cameras.
