FPGA-based real-time visual tracking system using adaptive color histograms

Visual tracking using a color feature is based on pattern matching algorithms where the appearance of the target is compared with a reference model in successive images and the position of the target is estimated. The major drawback of these methods is that such operations are usually considered at the top level of image processing both due to the data´s intrinsic complexity and to the high computational cost associated with a solution in real time. The probabilistic tracking methods have been shown to be robust and versatile for a modest computational cost. However, the probabilistic tracking methods break down easily when the object moves very fast because these methods search only the regions of interest (ROIs) based on the probability density function (pdf) to estimate the position of the moving object. In this paper, we propose a real-time visual tracking circuit using adaptive color histograms. We propose a window- based image processing structure to improve the processing speed of the visual tracking circuit. The visual tracking circuit searches all regions of the image to perform a matching operation in order to estimate the position of the moving object. The main results of our work are that we have designed and implemented a physically feasible hardware circuit to improve the processing speed of the operations required for real-time visual tracking. Therefore, this work has resulted in the development of a real-time visual tracking system employing an FPGA (field programmable gate array) implemented circuit designed by VHDL (the VHSIC hardware description language). Its performance has been measured to compare with the equivalent software implementation.