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
FO_1I_D32F32C31_TRC_WRA_01(Biquad_Instance_t * pInstance,LVM_INT32 * pDataIn,LVM_INT32 * pDataOut,LVM_INT16 NrSamples)35 void 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