BQ_2I_D16F32C13_TRC_WRA_01.c revision 2c8e5cab3faa6d360e222b7a6c40a80083d021ac 
1/*
2 * Copyright (C) 2004-2010 NXP Software
3 * Copyright (C) 2010 The Android Open Source Project
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at
8 *
9 *      http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17
18/************************************************************************/
19/*                                                                      */
20/*     Project::                                                        */
21/*     $Author: beq07716 $*/
22/*     $Revision: 1000 $*/
23/*     $Date: 2010-06-28 13:08:20 +0200 (Mon, 28 Jun 2010) $*/
24/*                                                                      */
25/************************************************************************/
26
27#include "BIQUAD.h"
28#include "BQ_2I_D16F32Css_TRC_WRA_01_Private.h"
29#include "LVM_Macros.h"
30
31
32/**************************************************************************
33 ASSUMPTIONS:
34 COEFS-
35 pBiquadState->coefs[0] is A2, pBiquadState->coefs[1] is A1
36 pBiquadState->coefs[2] is A0, pBiquadState->coefs[3] is -B2
37 pBiquadState->coefs[4] is -B1, these are in Q13 format
38
39 DELAYS-
40 pBiquadState->pDelays[0] is x(n-1)L in Q0 format
41 pBiquadState->pDelays[1] is x(n-1)R in Q0 format
42 pBiquadState->pDelays[2] is x(n-2)L in Q0 format
43 pBiquadState->pDelays[3] is x(n-2)R in Q0 format
44 pBiquadState->pDelays[4] is y(n-1)L in Q16 format
45 pBiquadState->pDelays[5] is y(n-1)R in Q16 format
46 pBiquadState->pDelays[6] is y(n-2)L in Q16 format
47 pBiquadState->pDelays[7] is y(n-2)R in Q16 format
48***************************************************************************/
49
50void BQ_2I_D16F32C13_TRC_WRA_01 (           Biquad_Instance_t       *pInstance,
51                                            LVM_INT16                    *pDataIn,
52                                            LVM_INT16                    *pDataOut,
53                                            LVM_INT16                    NrSamples)
54    {
55        LVM_INT32  ynL,ynR,templ;
56        LVM_INT16 ii;
57        PFilter_State pBiquadState = (PFilter_State) pInstance;
58
59         for (ii = NrSamples; ii != 0; ii--)
60         {
61
62
63            /**************************************************************************
64                            PROCESSING OF THE LEFT CHANNEL
65            ***************************************************************************/
66            /* ynL=A2 (Q13) * x(n-2)L (Q0) in Q13*/
67            ynL=(LVM_INT32)pBiquadState->coefs[0]* pBiquadState->pDelays[2];
68
69            /* ynL+=A1 (Q13) * x(n-1)L (Q0) in Q13*/
70            ynL+=(LVM_INT32)pBiquadState->coefs[1]* pBiquadState->pDelays[0];
71
72            /* ynL+=A0 (Q13) * x(n)L (Q0) in Q13*/
73            ynL+=(LVM_INT32)pBiquadState->coefs[2]* (*pDataIn);
74
75            /* ynL+= ( (-B2 (Q13) * y(n-2)L (Q16) )>>16) in Q13 */
76            MUL32x16INTO32(pBiquadState->pDelays[6],pBiquadState->coefs[3],templ,16)
77            ynL+=templ;
78
79            /* ynL+=( (-B1 (Q13) * y(n-1)L (Q16) )>>16) in Q13 */
80            MUL32x16INTO32(pBiquadState->pDelays[4],pBiquadState->coefs[4],templ,16)
81            ynL+=templ;
82
83            /**************************************************************************
84                            PROCESSING OF THE RIGHT CHANNEL
85            ***************************************************************************/
86            /* ynR=A2 (Q13) * x(n-2)R (Q0) in Q13*/
87            ynR=(LVM_INT32)pBiquadState->coefs[0]*pBiquadState->pDelays[3];
88
89            /* ynR+=A1 (Q13) * x(n-1)R (Q0) in Q13*/
90            ynR+=(LVM_INT32)pBiquadState->coefs[1]*pBiquadState->pDelays[1];
91
92            /* ynR+=A0 (Q13) * x(n)R (Q0) in Q13*/
93            ynR+=(LVM_INT32)pBiquadState->coefs[2]*(*(pDataIn+1));
94
95            /* ynR+= ( (-B2 (Q13) * y(n-2)R (Q16) )>>16) in Q13*/
96            MUL32x16INTO32(pBiquadState->pDelays[7],pBiquadState->coefs[3],templ,16)
97            ynR+=templ;
98
99            /* ynR+=( (-B1 (Q13) * y(n-1)R (Q16) )>>16) in Q13 */
100            MUL32x16INTO32(pBiquadState->pDelays[5],pBiquadState->coefs[4],templ,16)
101            ynR+=templ;
102
103            /**************************************************************************
104                            UPDATING THE DELAYS
105            ***************************************************************************/
106            pBiquadState->pDelays[7]=pBiquadState->pDelays[5];  /* y(n-2)R=y(n-1)R*/
107            pBiquadState->pDelays[6]=pBiquadState->pDelays[4];  /* y(n-2)L=y(n-1)L*/
108            pBiquadState->pDelays[3]=pBiquadState->pDelays[1];  /* x(n-2)R=x(n-1)R*/
109            pBiquadState->pDelays[2]=pBiquadState->pDelays[0];  /* x(n-2)L=x(n-1)L*/
110            pBiquadState->pDelays[5]=ynR<<3;                    /* Update y(n-1)R in Q16*/
111            pBiquadState->pDelays[4]=ynL<<3;                    /* Update y(n-1)L in Q16*/
112            pBiquadState->pDelays[0]=(*pDataIn);                /* Update x(n-1)L in Q0*/
113            pDataIn++;
114            pBiquadState->pDelays[1]=(*pDataIn);                /* Update x(n-1)R in Q0*/
115            pDataIn++;
116
117            /**************************************************************************
118                            WRITING THE OUTPUT
119            ***************************************************************************/
120            *pDataOut=(LVM_INT16)(ynL>>13); /* Write Left output in Q0*/
121            pDataOut++;
122            *pDataOut=(LVM_INT16)(ynR>>13); /* Write Right ouput in Q0*/
123            pDataOut++;
124        }
125
126    }
127
128