Pitch estimation based on Circular AMDF

Pitch period is a key parameter in speech compression, synthesis and recognition. The AMDF is often used to determine this parameter. Due to the falling trend of the AMDF curve, however, it is easy to make the estimated pitch doubled or halved To correct these errors, the algoritlun has to increase its complexity. In this paper, we propose a new function, Circular AMDF (CAMDF), and describe a new pitch detection algoritlnn based on it. The CAMDF conquers the defect of AMDF, and brings us some useful features. which not only simplifies the procedure of estimation, but also efficiently reduces the estimation errors and improves the estimation precision. Lots of experiment shows that the performance of CAMDF outperforms the others AMDF-based functions, such as HRAMDF and LVAMDF.