This work presents the implementation of the Kanade-Lucas-Tomasi tracking algorithm on a Digital Signal Processor with a 40-bit fixed-point Arithmetic Logic Unit built into a smart camera. The main goal of this work was to obtain realtime frame processing performance while loosing as little tracking accuracy as possible. This task was motivated by increasing demand for the application of smart cameras as main data processing units in large surveillance systems, where factors like cost and demand of space are excluding PCs from this role. In a first effort the modification of the Kanade-Lucas-Tomasi to integer numbers was performed and then in the next step the influence on stability and accuracy of this modification was investigated. It is demonstrated how changing the numeric data type of intermediate results within the algorithm from float to integer, and decreasing the number of bits used to store variables, affects tracking accuracy. Nevertheless the DSP implementation can be used where the computation of optical flow based on a tracking algorithm needs to be done in real-time on an embedded platform where limited subpixel accuracy can be tolerated. As a further result of this implementation we can conclude that a DSP with a fixed-point arithmetic logic unit can be very effectively applied for complex computer vision tasks and is able deliver good performance even compared to high-end PC architectures.

Date Published: 10 September 2007
PDF: 11 pages
Proc. SPIE 6764, Intelligent Robots and Computer Vision XXV: Algorithms, Techniques, and Active Vision, 67640B (10 September 2007); doi: 10.1117/12.734151

Published in SPIE Proceedings Vol. 6764:
Intelligent Robots and Computer Vision XXV: Algorithms, Techniques, and Active Vision
David P. Casasent; Ernest L. Hall; Juha Röning, Editor(s)