Cochlear Implant Speech Processing Using Wavelet Transform

Table 2

Comparison of approximate number of multiplications in various speech processing technique.

Approximate number of real multiplications for 𝑚=256 sample frame, 128-point FFT, 22 channels, and 𝑙=12, 24, and 30 length wavelet packet filter
Filter bank	FFT (N-point)	Recursive DFT update		Wavelet
Channels * (6th order BPF)	2𝑁(log2𝑁)+(𝑁/2)∗2	Rectangular window	2nd order all-pole window			𝑚∗𝑙∗7+(𝑚/8)∗channels∗5
		(𝑁/2)∗4+(𝑁/2)∗2	(𝑁/2)∗8+(𝑁/2)∗2
112 k	519 k	100 k	167 k	25 k	47 k	57 k