I. Introduction
Pitch is the perceived frequency at which vocal cords vibrate in voiced sounds. The pitch plays a key role in the human voice perception, speaker identity, prosodic information, emotions, and the speech itself. The pitch is also used in speech applications such as speech enhancement [1], speech coding [2], and speech recognition [3], [4]. It is used in many music applications such as bass tracking [5], automatic transcription [6], and melody extraction [7], [8]. Moreover, an accurate pitch is desired in various analyses of speech for different psychological and pathological conditions [9], [10].