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#include "BIQUAD.h"
19#include "FO_1I_D32F32Cll_TRC_WRA_01_Private.h"
20#include "LVM_Macros.h"
21
22
23/**************************************************************************
24 ASSUMPTIONS:
25 COEFS-
26 pBiquadState->coefs[0] is A1,
27 pBiquadState->coefs[1] is A0,
28 pBiquadState->coefs[2] is -B1, these are in Q31 format
29
30 DELAYS-
31 pBiquadState->pDelays[0] is x(n-1)L in Q0 format
32 pBiquadState->pDelays[1] is y(n-1)L in Q0 format
33***************************************************************************/
34
35void FO_1I_D32F32C31_TRC_WRA_01( Biquad_Instance_t       *pInstance,
36                                 LVM_INT32               *pDataIn,
37                                 LVM_INT32               *pDataOut,
38                                 LVM_INT16               NrSamples)
39    {
40        LVM_INT32  ynL,templ;
41        LVM_INT16  ii;
42        PFilter_State pBiquadState = (PFilter_State) pInstance;
43
44        for (ii = NrSamples; ii != 0; ii--)
45        {
46
47            /**************************************************************************
48                            PROCESSING OF THE LEFT CHANNEL
49            ***************************************************************************/
50            // ynL=A1 (Q31) * x(n-1)L (Q0) >>31 in Q0
51            MUL32x32INTO32(pBiquadState->coefs[0],pBiquadState->pDelays[0],ynL,31)
52
53            // ynL+=A0 (Q31) * x(n)L (Q0) >> 31 in Q0
54            MUL32x32INTO32(pBiquadState->coefs[1],*pDataIn,templ,31)
55            ynL+=templ;
56
57            // ynL+=  (-B1 (Q31) * y(n-1)L (Q0) ) >> 31 in Q0
58            MUL32x32INTO32(pBiquadState->coefs[2],pBiquadState->pDelays[1],templ,31)
59            ynL+=templ;
60
61            /**************************************************************************
62                            UPDATING THE DELAYS
63            ***************************************************************************/
64            pBiquadState->pDelays[1]=ynL; // Update y(n-1)L in Q0
65            pBiquadState->pDelays[0]=(*pDataIn++); // Update x(n-1)L in Q0
66
67            /**************************************************************************
68                            WRITING THE OUTPUT
69            ***************************************************************************/
70            *pDataOut++=(LVM_INT32)ynL; // Write Left output in Q0
71        }
72
73    }
74
75