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27
28 #ifdef HAVE_CONFIG_H
29 #include "config.h"
30 #endif
31
32 #include "SigProc_FLP.h"
33
34 /* step up function, converts reflection coefficients to prediction coefficients */
silk_k2a_FLP(silk_float * A,const silk_float * rc,opus_int32 order)35 void silk_k2a_FLP(
36 silk_float *A, /* O prediction coefficients [order] */
37 const silk_float *rc, /* I reflection coefficients [order] */
38 opus_int32 order /* I prediction order */
39 )
40 {
41 opus_int k, n;
42 silk_float Atmp[ SILK_MAX_ORDER_LPC ];
43
44 for( k = 0; k < order; k++ ) {
45 for( n = 0; n < k; n++ ) {
46 Atmp[ n ] = A[ n ];
47 }
48 for( n = 0; n < k; n++ ) {
49 A[ n ] += Atmp[ k - n - 1 ] * rc[ k ];
50 }
51 A[ k ] = -rc[ k ];
52 }
53 }
54