This paper introduces an affine invariant of trapezia, and the explicit constraint equation between the intrinsic matrix of a camera and the similarity invariants of a trapezium are established using the affine invariant. By this constraint, the inner parameters, motion parameters of the cameras and the similarity invariants of trapezia can be linearly determined using some prior knowledge on the cameras or the trapezia. The proposed algorithms have wide applicability since parallel lines are not rare in many scenes. Experimental results validate the proposed approaches. This work presents a unifying framework based on the parallelism constraint, and the previous methods based on the parallelograms or the parallelepipeds can be integrated into this framework.
Key words: invariant parallelism constraint camera calibration 3D reconstruction
Core Java 2 Volume I - Fundamentals, Seventh Edition
Completely revised and up-to-date coverage of
Generic programming, restrictions and limitations, type bounds, wilcard types, and generic reflection
Swing GUI development, including input validation and other enhancements
Exception handling and debugging, including chained exceptions, stack frames, assertions, and logging
Streams and files, the new I/O API, memory-mapped files, file locking, and character set encoders/decoders
Regular expressions using the powerful java.util.regex package
inner classes, reflection, and dynamic proxies
Application packaging and the Preferences API
DataDraw is an ultra-fast persistent database for high performance programs written in C. It s so fast that
many programs keep all their data in a DataDraw database, even whi le being manipulated in inner loop s
of compute intensive appl ications.
Abstract-The effect of the companding process on QAM signals
has been under investigation for the past several years. The
compander, included in the PCM telephone network to improve
voice performance, has an unusual affect on digital QAM data
signals which are transmitted over the same channel. The quantization
noise, generated by the companding process which is multiplicative
(and asymmetric), degrades the detectability performance
of the outermost points of the QAM constellation more
than that of the inner points.
The combined effect of the companding noise and the inherent
white gaussian noise of the system, leads us to a re-examination of
signal constellation design.
In this paper we investigate the detectability performance of a
number of candidates for signal constellations including, a typical
rectangular QAM constellation, the same constellation with the
addition of a smear-desmear operation, and two new improved
QAM constellation designs with two-dimensional warpi
In this book, you will learn about what drives the Linux development process. You will discover the wide
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understand your role as one of a budding new generation of Linux developers.
