Adaptively undersampled, circular histogram based image processing for rotation invariant coin detection

As in many real time signal processing application in image processing the computation time and the number of operations is very critical. Correlation as the most known and most widely used algorithm in image matching has a tendency to grow the number of operations rapidly when the range of discretion increases. In this paper adaptively undersampled circular histogram based image processing algorithm for the validation of fast moving and rotating coins has been developed and evaluated. The combination of adaptive undersampling and circular area histogram matching makes the method highly accurate and rotation invariant while significantly reducing the calculations operations needed for the validation of fast moving and rotating coins. This method has been tested on real euro coins and the results show that this method is suitable for accurate rotation invariant coin verification system.