windowfilter(1) [debian man page]

WINDOWFILTER(1) 					      General Commands Manual						   WINDOWFILTER(1)

NAME

       windowfilter - design an FIR digital filter by the window method

DESCRIPTION

       The  windowfilter  program designs an FIR digital filter for use with the resample program.  Just run the program and type ? at its prompts
       to get an explanation of its options.

REFERENCES

       Digital Signal Processing Committee, ed., Programs for Digital Signal Processing, IEEE Press, New York, 1979.

       J. F. Kaiser, "Using the I0-sinh Window Function," Proc. IEEE Int. Symp. on Circuits and Syst., April 22-25, pp. 20-23, 1974.

       F. J. Harris, "On the Use of Windows for Harmonic Analysis with the Discrete Fourier Transform," Proceedings of the IEEE, vol. 66,  no.	1,
       pp.  51-83. Jan. 1978.

       A.  H.  Nuttall,  "Some	Windows  with  Very  Good  Sidelobe Behavior," IEEE Transactions on Acoustics, Speech, and Signal Processing, vol.
       ASSP-29, no.  1, pp. 84-91, Feb. 1981.

       L. R. Rabiner and B. Gold, Theory and Application of Digital Signal Processing, Prentice-Hall Inc., Englewood Cliffs, NJ, 1975.

CCRMA
								    19 Jun 2002 						   WINDOWFILTER(1)

mlib_SignalCepstral_F32(3MLIB)				    mediaLib Library Functions				    mlib_SignalCepstral_F32(3MLIB)

NAME

       mlib_SignalCepstral_F32 - perform cepstral analysis

SYNOPSIS

       cc [ flag... ] file... -lmlib [ library... ]
       #include <mlib.h>

       mlib_status mlib_SignalCepstral_F32(mlib_f32 *cepst,
	    const mlib_f32 *signal, void *state);

DESCRIPTION

       The mlib_SignalCepstral_F32() function performs cepstral analysis.

       The basic operations to compute the cepstrum is shown below.

	       +-----------+	  +--------+	   +-----------+
	       |  Fourier  |	  |	   |	   |  Inverse  |
	 ----->|	   |----->| log|*| |------>|  Fourier  |----->
	  x(n) | Transform | X(k) |	   | X'(k) | Transform | c(n)
	       +-----------+	  +--------+	   +-----------+

       where x(n) is the input signal and c(n) is its cepstrum. In mathematics, they are

		N-1		   2*PI*k*n
	 X(k) = SUM x(n) * exp(-j*----------)
		n=0		      N

	 X'(k) = log|X(k)|

		 1  N-1 	       2*PI*k*n
	 c(n) = --- SUM X'(k) * exp(j*----------)
		 N  n=0 		  N

       Since X'(k) is real and even (symmetric), i.e.

	 X'(k) = X'(N - k)

       the c(n) is real and the equation becomes Cosine transform.

		 1  N-1 	     2*PI*k*n
	 c(n) = --- SUM X'(k) * cos(----------)
		 N  n=0 		N

       The cepstral coefficients in LPC is a special case of the above.

       See Digital Signal Processing by Alan V. Oppenheim and Ronald W. Schafer, Prentice Hall, 1974.

       See Fundamentals of Speech Recognition by Lawrence Rabinerand Biing-Hwang Juang, Prentice Hall, 1993.

PARAMETERS

       The function takes the following arguments:

       cepst	 The cepstral coefficients.

       signal	 The input signal vector.

       state	 Pointer to the internal state structure.

RETURN VALUES

       The function returns MLIB_SUCCESS if successful. Otherwise it returns MLIB_FAILURE.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Committed 		   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |MT-Safe			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       mlib_SignalCepstralInit_F32(3MLIB), mlib_SignalCepstralFree_F32(3MLIB), attributes(5)

SunOS 5.11							    2 Mar 2007					    mlib_SignalCepstral_F32(3MLIB)