Introduction of consumer-grade panoramic camera:
Millet
April 5 Xiaomi released the Mijia panoramic camera, which consists of two 190° fisheye lens cameras. It does not need to be used with a cell phone and can be used independently.
Mijia parameters: Anba A12 processor, Sony IMX 206 sensor, 23.88 million effective pixels, built-in 6-axis electronic stabilization, the use of either flip, tilt, yaw, can be corrected in real time and get a stable and smooth picture. Meets IP67 waterproof and dustproof certification. It can meet the daily shooting needs of home, outdoor and news. Priced at $1699.
Nubia
On April 6, Nubia released the NeoAirVR panoramic camera. Equipped with two 210-degree fisheye wide-angle lenses, it can take pictures with a resolution of 3008×1504, video with a resolution of 2560×1280 and a frame rate of 30fps, panoramic content is automatically spliced without post-processing, and it supports a variety of modes such as fisheye, asteroids, crystal ball, perspective, and so on.
Priced at 699, it can only be used with a cell phone (currently only supports Android phones), and cannot be used independently, which is one of the major reasons why it is 1000 cheaper than Xiaomi.
Ricoh
Ricoh has announced a public demonstration of its new THETA 360 panoramic camera, which is the latest development, at the 2017 National Broadcast Equipment Show. The new camera's best feature will be its ability to capture 360 panorama video at 30fps 4K resolution while recording in stereo using a built-in four-channel microphone.
Professional-grade panoramic camera
In late April, Google unveiled YiHalo, an upgraded version of its Jump camera. Developed by Xiaomi's Ant in collaboration with Google, YiHalo consists of 17 cameras, with 16 assembled into a circular array in a wrap-around format, and one mounted on top of a disk.
YiHalo uses the Amba A9SE75 chip and Sony's 12-megapixel IMX377 sensor. Capable of shooting video at 8k resolution at 30 frames per second / 5.8k resolution at 60 frames per second. Priced at ?16,999, it is aimed at professional video content production teams.
Facebook announced the Surround 360 X24/X6 panoramic cameras on April 20th.
The X24 consists of 24 cameras and the X6 consists of 6 cameras. Unlike the previous Surround 360's disk design approach, both the X24/X6 are spherical. Support for shooting video at up to 8K resolution in 6 degrees of freedom (6DoF), with 6DOF tracking, both Facebook's own OculusRift and HTC's Vive users will be able to move in any direction the footage is captured in, rather than just viewing the entire scene in 360 degrees from a fixed center position. Currently, that effect can only be achieved with computer-generated images.
Several important parameters of the panoramic camera are as follows:
1, the number of cameras: panoramic camera using multiple cameras (at least 2) splicing, the more the number of cameras, the higher the number of effective pixels per unit of angle, the smaller the distortion of the picture, the better the visual effect, but the corresponding amount of computation is also the greater the difficulty of splicing, the greater the cost of hardware and algorithms. Currently, panoramic camera solutions with less than 6 cameras can barely achieve in-camera splicing, and more than 6 cameras are generally spliced on dedicated workstations.
2, resolution: including picture resolution, video resolution. For the picture resolution, consumer panoramic camera mainstream is 4K, and professional panoramic camera up to 8K.
3, picture quality: picture quality is the quality of the final picture, including detail resolution, level, contrast, etc.. The main impact on image quality lies in the image CMOS sensor imaging quality and ISP chip processing algorithms.
4, imaging consistency. Mainly refers to the exposure, white balance and other parameters. Panoramic camera based on multiple camera splicing, when the scene has a unidirectional strong light source (such as the morning oblique sun), different angles of the camera incident light intensity is different, the exposure parameters vary greatly. This results in inconsistent exposure, which can be clearly seen in the picture with inconsistent brightness, seriously affecting the stitching algorithm.
5, safe distance: many panoramic cameras rely on the overlap of neighboring lenses to capture the picture, matching *** the same features to achieve splicing. When the object being photographed is closer to the camera, there are few *** same features, and splicing is prone to distortion or misalignment. This critical distance is the safety distance. The smaller the safety distance, the better.
6, in-camera splicing: that is, inside the panoramic camera to complete the panoramic image splicing, so that the operation of the use is very convenient, but the in-camera splicing of heat, computing performance and other aspects of the requirements of the machine is relatively high, the number of cameras is less than 6 easy to realize.
Double fisheye panoramic camera problems
Double fisheye technology program is currently the mainstream panoramic camera program, but the double fisheye technology is not the most ideal panoramic camera program.
Double fisheye panoramic camera because it needs two cameras with the same overlap area to stitch, so each fisheye lens is above 180 °, 190 ° and 200 ° is the most common. And such a large field of view angle of the fisheye lens will produce many problems. Summarized, there are three main:
Serious distortion at the edges of the screen
The degree of distortion of the fisheye image is from the center of the circle to the surrounding gradually become larger. Generally the center of the image is quite normal, but the surrounding area will be distorted more seriously, as shown in the following figure around the people and the roof of the house are seriously distorted. This is not good for stitching after the fisheye is deployed.
Large safety distance
The smaller the safety distance, the better. However, the technical solution of double fisheye makes the safety distance large, and the human arm can't be put together well when shooting handheld. Or when shooting in small spaces such as indoors, pillars or ceilings are prone to breaks and distortions.
Low Effective Pixels Per Angle
The COMS sensor used in a fisheye camera is actually no different from that of a regular camera, but because it utilizes only a portion of the rounded middle of the square COMS, there is less effective sensor area, and because a fisheye lens covers a field of view that is much larger than the normal field of view, there is very little effective pixel per degree of angle of view. For example, a panoramic camera consisting of two 12-megapixel fisheye lenses may be only about one-thirtieth the size of a 12-megapixel cell phone with a normal field of view (generally less than 70°) when translated per unit of angle.
Current shooting equipment classification
Before introducing the development trend of panoramic camera, let's talk about the current shooting equipment classification. Currently shooting equipment is mainly divided into three categories: cell phone camera, camera camera, film and television cameras.
One of the cell phone camera face ordinary personal users, the shooting quality requirements are not high, but the price is sensitive. Generally used to shoot life photos, travel photos and so on.
The film and television camera equipment is facing the professional film and television production company, the imaging quality of the equipment, the stability of the long time working requirements are very high. The price is also very high.
The camera is between the two, the most common is the SLR camera. There are both consumer-grade products for ordinary users and professional-grade products for professional users.
Future development trend of panoramic camera
Future panoramic camera is likely to be divided into three corresponding development direction like the above mentioned shooting equipment.
Panoramic camera as a cell phone accessory
Because of the limitations of the cell phone body size (especially thickness), the cell phone lens can't have a large-size sensor, a wide range of adjustable aperture, a wide range of adjustable focus and a series of other functions like a DSLR. Therefore panoramic camera as a cell phone in the camera an extension of its raison d'être.
This type of panoramic camera is mainly used in the double fisheye technology program, R & D main cell phone manufacturers (Samsung, millet, Nubia, LG, etc.) and some third-party manufacturers (Ricoh, insta 360, etc.).
This direction of the panoramic camera is currently more, the development is more mature, China Augmented Reality Industry Alliance that the future development trend:
1, miniaturization. Because it is mainly used with cell phones, it is very important to be lightweight and compact.
2, foolproof. Can realize automatic panoramic splicing, real-time preview, no need to pass the computer directly to the phone. Simple operation, can quickly get started.
3, ecological. Provide supporting APP software, support picture editing character beautification, mainstream social software sharing, value-added services and other functions. Form a complete industrial chain.