Autocorr - Analog Devices VISUALDSP++ 3.5 Manual

autocorr

autocorrelation
Synopsis
#include <stats.h>
void autocorrf(a,n,m,c)
const float a[];
int n;
int m;
float c[];
void autocorr_fr16 (a,n,m,c)
const fract16 a[];
int n;
int m;
fract16 c[];
Description
This function computes the autocorrelation of the input elements con-
tained within input vector
autocorr function is used in digital signal processing applications such as
speech analysis.
Algorithm
− −
n k 1
1
∑
=
c * ( a
k
n
=
j 0
where k={0,1,...,m-1}
Domain
38
-3.4 x 10 to +3.4 x 10
-1.0 to + 1.0
VisualDSP++ 3.5 C/C++ Compiler and Library Manual
for ADSP-219x DSPs
, and stores the result to output vector
a
* a )
+
j j k
38
DSP Run-Time Library
/* Input vector a
/* Number of input samples */
/* Lag count
/* Output vector c
/* Input vector a
/* Number of input samples */
/* Lag count
/* Output vector c
for
autocorrf( )
for
autocorr_fr16( )
*/
*/
*/
*/
*/
*/
. The
c
4-29