Efficient and accurate pitch estimation using FFT

The spectral information of sinusoids normally available from FFT does not give enough information about the exact frequency location of the sinusoid. The power of the sinusoids is usually split between the two nearby frequency bins when the location of the sinusoid does not coincide exactly with the location of the frequency bins. Using these power values the exact sinusoid frequency and hence the pitch frequency can be determined. Two solutions, one exact and one approximate are derived. The results obtained from both the algorithms provide very good approximation to the exact frequency location of the sinusoids