Critical alignment through Parallax Induction
Critical alignment is a method for generating an autostereoscopic display from source images with parallax differences.1 After acquiring parallax images and aligning at least a portion of the first parallax image with the corresponding portion of another parallax image, a dimensional view is generated by alternating the first parallax image and second parallax image at frequencies between 3 – 6 Hz.2
Following the alignment, computational analysis may be performed on the images. Quantitative information may be extracted from the aligned parallax images. As a result of the parallax information contained in the images, an apparent shift of an object may exist between different views. The apparent shift refers to the distance a point in an image appears to move between images taken from different points of view. By measuring the amount of apparent shift of a point in two or more parallax images, quantitative position values may be computed for the point in relation to objects in the image if certain other information, such as the distance between the camera and a point in the image, is known. For example, by knowing the distance between the camera and the ground in an image captured from the air, and by measuring the apparent shift of the top edge of a building between two or more parallax images, the height and/or volume of the building may be calculated.
See also
parallax scanning
Parallax Image Display (PID™)
References
1. Mayhew, C. et al., "Three-Dimensional Visualization of Geographical Terrain Data Using Temporal Parallax Difference Induction", IS&T/SPIE Paper No. 7240-26, San Jose, CA, January 22, 2009 p.3
2. WIPO Publication No. WO/2004/049736, CRITICAL ALIGNMENT OF PARALLAX IMAGES FOR AUTOSTEREOSCOPIC DISPLAY