Exploring Catadioptric Panoramas: A Technological Study

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2.5 Capturing panorama by spatial camera equipment
2.5.1 Catadioptric Panoramas
A catadioptric camera system enables us to record a full “half sphere image’’ in one shot. The word catadioptric means pertaining to or involving both the reflection and the refraction of light. A catadioptric camera system is engineered as a combination of a quadric mirror and a conventional sensor-matrix camera; see Figure ‎2 2. Catadioptric camera systems provide real-time and highly portable imaging capabilities at affordable cost. Figure ‎2 2(a) a commercial catadioptric camera system. The shape of the mirror has been emphasized by an added black curve for clarity. (b) an image taken by this panoramic sensor. (c) a panorama produced by rectifying the …show more content…

Both catadioptric sensors allow that all the reflected projection rays intersect at a single point, and hence possess a simple computational model which supports various applications. Both sensor models are illustrated in Figure ‎2 3. Figure ‎2 3 Catadioptric panoramas: Parabolic mirror with orthographic projection (left), and hyperboloidal mirror with perspective projection (right).
The major drawbacks of the catadioptric approach include low resolution near the center of an image, non-uniform spatial sampling, inefficient usage of images (i.e., there is a self-occluded or mirror-occluded area in each captured image), severe distortions and image blurring due to aberrations caused by coma, astigmatism, field curvature, and chromatic aberration.
These drawbacks suggest that catadioptric panoramas are not suitable for those recognition or inspection types of applications where high accuracy or high image resolution is required (as in close-range photogrammetry).
2.5.2 Camera with Fish-eye …show more content…

In interiors however, lighting conditions are rarely ideal, in dark spaces this method of recording can last for several hours (!).
2.6 Construction Digital Panoramas
There are many methods to Create Digital Panoramas
2.6.1 Image Mosaicing
Image mosaicing is often just a single component of a rather complex project.
An image mosaicing method assumes motion-uncontrolled image sequences (see Figure ‎2 7 (a) Motion-controlled and (b) motion-uncontrolled scanning.(b)), or just sets of images (e.g., taken by different satellites on different days, at different elevations, and with various resolutions above the same location).
Mosaicing is simplified if the non-rotational motion of the camera can be controlled (to some extent). For example, a geostationary satellite, which is constantly looking down at a fixed angle, provides ideal conditions for mosaicing. Figure ‎2 7 (a) Motion-controlled and (b) motion-uncontrolled scanning.
(Huang et al., 2008)

The problem of accurate mosaicing appears in photogrammetry, computer vision, image processing, and computer graphics. Application areas of mosaicing include change detection. (Huang et al.,

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