ref: 205443a1cccac1dcd3e9648ef53b7b7eba4e1fb8
dir: /amr-wb/int_lpc.c/
/*-----------------------------------------------------------------------* * HP400.C * *-----------------------------------------------------------------------* * Interpolation of the LP parameters in 4 subframes. * *-----------------------------------------------------------------------*/ #include "typedef.h" #include "basic_op.h" #include "cnst.h" #include "acelp.h" #include "count.h" #define MP1 (M+1) void Int_isp( Word16 isp_old[], /* input : isps from past frame */ Word16 isp_new[], /* input : isps from present frame */ Word16 frac[], /* input : fraction for 3 first subfr (Q15) */ Word16 Az[] /* output: LP coefficients in 4 subframes */ ) { Word16 i, k, fac_old, fac_new; Word16 isp[M]; Word32 L_tmp; for (k = 0; k < 3; k++) { fac_new = frac[k]; move16(); fac_old = add(sub(32767, fac_new), 1); /* 1.0 - fac_new */ for (i = 0; i < M; i++) { L_tmp = L_mult(isp_old[i], fac_old); L_tmp = L_mac(L_tmp, isp_new[i], fac_new); isp[i] = round(L_tmp); move16(); } Isp_Az(isp, Az, M, 0); Az += MP1; } /* 4th subframe: isp_new (frac=1.0) */ Isp_Az(isp_new, Az, M, 0); return; }