1e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard/* 2e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard ** Copyright 2003-2010, VisualOn, Inc. 3e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard ** 4e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard ** Licensed under the Apache License, Version 2.0 (the "License"); 5e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard ** you may not use this file except in compliance with the License. 6e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard ** You may obtain a copy of the License at 7e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard ** 8e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard ** http://www.apache.org/licenses/LICENSE-2.0 9e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard ** 10e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard ** Unless required by applicable law or agreed to in writing, software 11e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard ** distributed under the License is distributed on an "AS IS" BASIS, 12e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard ** See the License for the specific language governing permissions and 14e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard ** limitations under the License. 15e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard */ 16e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard 17e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard/*********************************************************************** 18e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard* File: deemph.c * 19e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard* * 20e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard* Description:filtering through 1/(1-mu z^ -1) * 21e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard* Deemph2 --> signal is divided by 2 * 22e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard* Deemph_32 --> for 32 bits signal. * 23e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard* * 24e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard************************************************************************/ 25e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard 26e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard#include "typedef.h" 27e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard#include "basic_op.h" 28e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard#include "math_op.h" 29e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard 30e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgardvoid Deemph( 31e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard Word16 x[], /* (i/o) : input signal overwritten by the output */ 32e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard Word16 mu, /* (i) Q15 : deemphasis factor */ 33e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard Word16 L, /* (i) : vector size */ 34e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard Word16 * mem /* (i/o) : memory (y[-1]) */ 35e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard ) 36e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard{ 37e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard Word32 i; 38e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard Word32 L_tmp; 39e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard 40e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard L_tmp = L_deposit_h(x[0]); 41e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard L_tmp = L_mac(L_tmp, *mem, mu); 42b676a05348e4c516fa8b57e33b10548e6142c3f8Mans Rullgard x[0] = vo_round(L_tmp); 43e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard 44e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard for (i = 1; i < L; i++) 45e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard { 46e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard L_tmp = L_deposit_h(x[i]); 47e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard L_tmp = L_mac(L_tmp, x[i - 1], mu); 48b676a05348e4c516fa8b57e33b10548e6142c3f8Mans Rullgard x[i] = voround(L_tmp); 49e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard } 50e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard 51b676a05348e4c516fa8b57e33b10548e6142c3f8Mans Rullgard *mem = x[L - 1]; 52e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard 53e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard return; 54e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard} 55e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard 56e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard 57e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgardvoid Deemph2( 58e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard Word16 x[], /* (i/o) : input signal overwritten by the output */ 59e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard Word16 mu, /* (i) Q15 : deemphasis factor */ 60e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard Word16 L, /* (i) : vector size */ 61e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard Word16 * mem /* (i/o) : memory (y[-1]) */ 62e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard ) 63e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard{ 64e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard Word32 i; 65e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard Word32 L_tmp; 66e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard L_tmp = x[0] << 15; 67e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard L_tmp += ((*mem) * mu)<<1; 68b676a05348e4c516fa8b57e33b10548e6142c3f8Mans Rullgard x[0] = (L_tmp + 0x8000)>>16; 69e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard for (i = 1; i < L; i++) 70e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard { 71e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard L_tmp = x[i] << 15; 72e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard L_tmp += (x[i - 1] * mu)<<1; 73b676a05348e4c516fa8b57e33b10548e6142c3f8Mans Rullgard x[i] = (L_tmp + 0x8000)>>16; 74e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard } 75b676a05348e4c516fa8b57e33b10548e6142c3f8Mans Rullgard *mem = x[L - 1]; 76e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard return; 77e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard} 78e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard 79e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard 80e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgardvoid Deemph_32( 81e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard Word16 x_hi[], /* (i) : input signal (bit31..16) */ 82e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard Word16 x_lo[], /* (i) : input signal (bit15..4) */ 83e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard Word16 y[], /* (o) : output signal (x16) */ 84e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard Word16 mu, /* (i) Q15 : deemphasis factor */ 85e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard Word16 L, /* (i) : vector size */ 86e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard Word16 * mem /* (i/o) : memory (y[-1]) */ 87e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard ) 88e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard{ 89e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard Word16 fac; 90e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard Word32 i, L_tmp; 91e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard 92e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard fac = mu >> 1; /* Q15 --> Q14 */ 93e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard 94e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard L_tmp = L_deposit_h(x_hi[0]); 95e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard L_tmp += (x_lo[0] * 8)<<1; 96e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard L_tmp = (L_tmp << 3); 97e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard L_tmp += ((*mem) * fac)<<1; 98b676a05348e4c516fa8b57e33b10548e6142c3f8Mans Rullgard L_tmp = (L_tmp << 1); 99b676a05348e4c516fa8b57e33b10548e6142c3f8Mans Rullgard y[0] = (L_tmp + 0x8000)>>16; 100e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard 101e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard for (i = 1; i < L; i++) 102e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard { 103e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard L_tmp = L_deposit_h(x_hi[i]); 104e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard L_tmp += (x_lo[i] * 8)<<1; 105e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard L_tmp = (L_tmp << 3); 106e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard L_tmp += (y[i - 1] * fac)<<1; 107b676a05348e4c516fa8b57e33b10548e6142c3f8Mans Rullgard L_tmp = (L_tmp << 1); 108b676a05348e4c516fa8b57e33b10548e6142c3f8Mans Rullgard y[i] = (L_tmp + 0x8000)>>16; 109e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard } 110e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard 111b676a05348e4c516fa8b57e33b10548e6142c3f8Mans Rullgard *mem = y[L - 1]; 112e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard 113e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard return; 114e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard} 115e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard 116e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard 117e2e838afcf03e603a41a0455846eaf9614537c16Mans Rullgard 118