| /* |
| ** Copyright 2003-2010, VisualOn, Inc. |
| ** |
| ** Licensed under the Apache License, Version 2.0 (the "License"); |
| ** you may not use this file except in compliance with the License. |
| ** You may obtain a copy of the License at |
| ** |
| ** http://www.apache.org/licenses/LICENSE-2.0 |
| ** |
| ** Unless required by applicable law or agreed to in writing, software |
| ** distributed under the License is distributed on an "AS IS" BASIS, |
| ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| ** See the License for the specific language governing permissions and |
| ** limitations under the License. |
| */ |
| |
| /*********************************************************************** |
| * File: syn_filt.c * |
| * * |
| * Description: Do the synthesis filtering 1/A(z) * |
| * * |
| ************************************************************************/ |
| |
| #include "typedef.h" |
| #include "basic_op.h" |
| #include "math_op.h" |
| #include "cnst.h" |
| |
| #define UNUSED(x) (void)(x) |
| |
| void Syn_filt( |
| Word16 a[], /* (i) Q12 : a[m+1] prediction coefficients */ |
| Word16 x[], /* (i) : input signal */ |
| Word16 y[], /* (o) : output signal */ |
| Word16 lg, /* (i) : size of filtering */ |
| Word16 mem[], /* (i/o) : memory associated with this filtering. */ |
| Word16 update /* (i) : 0=no update, 1=update of memory. */ |
| ) |
| { |
| Word32 i, a0; |
| Word16 y_buf[L_SUBFR16k + M16k]; |
| Word32 L_tmp; |
| Word16 *yy, *p1, *p2; |
| yy = &y_buf[0]; |
| /* copy initial filter states into synthesis buffer */ |
| for (i = 0; i < 16; i++) |
| { |
| *yy++ = mem[i]; |
| } |
| a0 = (a[0] >> 1); /* input / 2 */ |
| /* Do the filtering. */ |
| for (i = 0; i < lg; i++) |
| { |
| p1 = &a[1]; |
| p2 = &yy[i-1]; |
| L_tmp = vo_mult32(a0, x[i]); |
| L_tmp -= vo_mult32((*p1++), (*p2--)); |
| L_tmp -= vo_mult32((*p1++), (*p2--)); |
| L_tmp -= vo_mult32((*p1++), (*p2--)); |
| L_tmp -= vo_mult32((*p1++), (*p2--)); |
| L_tmp -= vo_mult32((*p1++), (*p2--)); |
| L_tmp -= vo_mult32((*p1++), (*p2--)); |
| L_tmp -= vo_mult32((*p1++), (*p2--)); |
| L_tmp -= vo_mult32((*p1++), (*p2--)); |
| L_tmp -= vo_mult32((*p1++), (*p2--)); |
| L_tmp -= vo_mult32((*p1++), (*p2--)); |
| L_tmp -= vo_mult32((*p1++), (*p2--)); |
| L_tmp -= vo_mult32((*p1++), (*p2--)); |
| L_tmp -= vo_mult32((*p1++), (*p2--)); |
| L_tmp -= vo_mult32((*p1++), (*p2--)); |
| L_tmp -= vo_mult32((*p1++), (*p2--)); |
| L_tmp -= vo_mult32((*p1), (*p2)); |
| |
| L_tmp = L_shl2(L_tmp, 4); |
| y[i] = yy[i] = extract_h(L_add(L_tmp, 0x8000)); |
| } |
| /* Update memory if required */ |
| if (update) |
| for (i = 0; i < 16; i++) |
| { |
| mem[i] = yy[lg - 16 + i]; |
| } |
| return; |
| } |
| |
| |
| void Syn_filt_32( |
| Word16 a[], /* (i) Q12 : a[m+1] prediction coefficients */ |
| Word16 m, /* (i) : order of LP filter */ |
| Word16 exc[], /* (i) Qnew: excitation (exc[i] >> Qnew) */ |
| Word16 Qnew, /* (i) : exc scaling = 0(min) to 8(max) */ |
| Word16 sig_hi[], /* (o) /16 : synthesis high */ |
| Word16 sig_lo[], /* (o) /16 : synthesis low */ |
| Word16 lg /* (i) : size of filtering */ |
| ) |
| { |
| Word32 i,a0; |
| Word32 L_tmp, L_tmp1; |
| Word16 *p1, *p2, *p3; |
| UNUSED(m); |
| |
| a0 = a[0] >> (4 + Qnew); /* input / 16 and >>Qnew */ |
| /* Do the filtering. */ |
| for (i = 0; i < lg; i++) |
| { |
| L_tmp = 0; |
| L_tmp1 = 0; |
| p1 = a; |
| p2 = &sig_lo[i - 1]; |
| p3 = &sig_hi[i - 1]; |
| |
| L_tmp -= vo_mult32((*p2--), (*p1)); |
| L_tmp1 -= vo_mult32((*p3--), (*p1++)); |
| L_tmp -= vo_mult32((*p2--), (*p1)); |
| L_tmp1 -= vo_mult32((*p3--), (*p1++)); |
| L_tmp -= vo_mult32((*p2--), (*p1)); |
| L_tmp1 -= vo_mult32((*p3--), (*p1++)); |
| L_tmp -= vo_mult32((*p2--), (*p1)); |
| L_tmp1 -= vo_mult32((*p3--), (*p1++)); |
| L_tmp -= vo_mult32((*p2--), (*p1)); |
| L_tmp1 -= vo_mult32((*p3--), (*p1++)); |
| L_tmp -= vo_mult32((*p2--), (*p1)); |
| L_tmp1 -= vo_mult32((*p3--), (*p1++)); |
| L_tmp -= vo_mult32((*p2--), (*p1)); |
| L_tmp1 -= vo_mult32((*p3--), (*p1++)); |
| L_tmp -= vo_mult32((*p2--), (*p1)); |
| L_tmp1 -= vo_mult32((*p3--), (*p1++)); |
| L_tmp -= vo_mult32((*p2--), (*p1)); |
| L_tmp1 -= vo_mult32((*p3--), (*p1++)); |
| L_tmp -= vo_mult32((*p2--), (*p1)); |
| L_tmp1 -= vo_mult32((*p3--), (*p1++)); |
| L_tmp -= vo_mult32((*p2--), (*p1)); |
| L_tmp1 -= vo_mult32((*p3--), (*p1++)); |
| L_tmp -= vo_mult32((*p2--), (*p1)); |
| L_tmp1 -= vo_mult32((*p3--), (*p1++)); |
| L_tmp -= vo_mult32((*p2--), (*p1)); |
| L_tmp1 -= vo_mult32((*p3--), (*p1++)); |
| L_tmp -= vo_mult32((*p2--), (*p1)); |
| L_tmp1 -= vo_mult32((*p3--), (*p1++)); |
| L_tmp -= vo_mult32((*p2--), (*p1)); |
| L_tmp1 -= vo_mult32((*p3--), (*p1++)); |
| L_tmp -= vo_mult32((*p2--), (*p1)); |
| L_tmp1 -= vo_mult32((*p3--), (*p1++)); |
| |
| L_tmp = L_tmp >> 11; |
| L_tmp += vo_L_mult(exc[i], a0); |
| |
| /* sig_hi = bit16 to bit31 of synthesis */ |
| L_tmp = L_tmp - (L_tmp1<<1); |
| |
| L_tmp = L_tmp >> 3; /* ai in Q12 */ |
| sig_hi[i] = extract_h(L_tmp); |
| |
| /* sig_lo = bit4 to bit15 of synthesis */ |
| L_tmp >>= 4; /* 4 : sig_lo[i] >> 4 */ |
| sig_lo[i] = (Word16)((L_tmp - (sig_hi[i] << 13))); |
| } |
| |
| return; |
| } |
| |
| |
| |
| |