| /* |
| * Copyright (C) 2004-2010 NXP Software |
| * Copyright (C) 2010 The Android Open Source Project |
| * |
| * 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. |
| */ |
| |
| /************************************************************************************/ |
| /* */ |
| /* Includes */ |
| /* */ |
| /************************************************************************************/ |
| |
| #include <system/audio.h> |
| #include "LVCS.h" |
| #include "LVCS_Private.h" |
| #include "LVCS_StereoEnhancer.h" |
| #include "VectorArithmetic.h" |
| #include "LVCS_Tables.h" |
| |
| /************************************************************************************/ |
| /* */ |
| /* FUNCTION: LVCS_StereoEnhanceInit */ |
| /* */ |
| /* DESCRIPTION: */ |
| /* Initialises the stereo enhancement module based on the sample rate. */ |
| /* */ |
| /* The function selects the coefficients for the filters and clears the data */ |
| /* history. It is also used for re-initialisation when one of the system control */ |
| /* parameters changes but will only change the coefficients and clear the history */ |
| /* if the sample rate or speaker type has changed. */ |
| /* */ |
| /* PARAMETERS: */ |
| /* hInstance Instance Handle */ |
| /* pParams Initialisation parameters */ |
| /* */ |
| /* RETURNS: */ |
| /* LVCS_Success Always succeeds */ |
| /* */ |
| /* NOTES: */ |
| /* */ |
| /************************************************************************************/ |
| LVCS_ReturnStatus_en LVCS_SEnhancerInit(LVCS_Handle_t hInstance, LVCS_Params_t* pParams) { |
| LVM_UINT16 Offset; |
| LVCS_Instance_t* pInstance = (LVCS_Instance_t*)hInstance; |
| const BiquadA012B12CoefsSP_t* pSESideCoefs; |
| |
| /* |
| * If the sample rate or speaker type has changed update the filters |
| */ |
| if ((pInstance->Params.SampleRate != pParams->SampleRate) || |
| (pInstance->Params.SpeakerType != pParams->SpeakerType)) { |
| /* |
| * Set the filter coefficients based on the sample rate |
| */ |
| /* Mid filter */ |
| Offset = (LVM_UINT16)pParams->SampleRate; |
| |
| std::array<LVM_FLOAT, android::audio_utils::kBiquadNumCoefs> coefs = { |
| LVCS_SEMidCoefTable[Offset].A0, LVCS_SEMidCoefTable[Offset].A1, 0.0, |
| LVCS_SEMidCoefTable[Offset].B1, 0.0}; |
| pInstance->pSEMidBiquad.reset( |
| new android::audio_utils::BiquadFilter<LVM_FLOAT>(FCC_1, coefs)); |
| |
| Offset = (LVM_UINT16)(pParams->SampleRate); |
| pSESideCoefs = (BiquadA012B12CoefsSP_t*)&LVCS_SESideCoefTable[0]; |
| |
| /* Side filter */ |
| coefs = {pSESideCoefs[Offset].A0, pSESideCoefs[Offset].A1, pSESideCoefs[Offset].A2, |
| pSESideCoefs[Offset].B1, pSESideCoefs[Offset].B2}; |
| pInstance->pSESideBiquad.reset( |
| new android::audio_utils::BiquadFilter<LVM_FLOAT>(FCC_1, coefs)); |
| } |
| |
| return (LVCS_SUCCESS); |
| } |
| /************************************************************************************/ |
| /* */ |
| /* FUNCTION: LVCS_StereoEnhance */ |
| /* */ |
| /* DESCRIPTION: */ |
| /* Enhance the stereo image in the input samples based on the following block */ |
| /* diagram: */ |
| /* */ |
| /* ________ */ |
| /* ________ | | ________ */ |
| /* | | Middle | Treble | | | */ |
| /* | |---------->| Boost |-------->| | */ |
| /* | Stereo | |________| | M & S | */ |
| /* -->| to | ________ | to |--> */ |
| /* | M & S | Side | | | Stereo | */ |
| /* | |---------->| Side |-------->| | */ |
| /* |________| | Boost | |________| */ |
| /* |________| */ |
| /* */ |
| /* */ |
| /* If the input signal is a mono signal there will be no side signal and hence */ |
| /* the side filter will not be run. In mobile speaker mode the middle filter is */ |
| /* not required and the Trebble boost filter is replaced by a simple gain block. */ |
| /* */ |
| /* */ |
| /* PARAMETERS: */ |
| /* hInstance Instance Handle */ |
| /* pInData Pointer to the input data */ |
| /* pOutData Pointer to the output data */ |
| /* NumSamples Number of samples to process */ |
| /* */ |
| /* RETURNS: */ |
| /* LVCS_Success Always succeeds */ |
| /* */ |
| /* NOTES: */ |
| /* 1. The side filter is not used in Mobile Speaker mode */ |
| /* */ |
| /************************************************************************************/ |
| LVCS_ReturnStatus_en LVCS_StereoEnhancer(LVCS_Handle_t hInstance, const LVM_FLOAT* pInData, |
| LVM_FLOAT* pOutData, LVM_UINT16 NumSamples) { |
| LVCS_Instance_t* pInstance = (LVCS_Instance_t*)hInstance; |
| LVCS_StereoEnhancer_t* pConfig = (LVCS_StereoEnhancer_t*)&pInstance->StereoEnhancer; |
| LVM_FLOAT* pScratch; |
| pScratch = (LVM_FLOAT*)pInstance->pScratch; |
| LVM_INT32 NumChannels = pInstance->Params.NrChannels; |
| LVM_UINT16 destNumSamples = (NumChannels == FCC_1) ? NumSamples : FCC_2 * NumSamples; |
| /* |
| * Check if the Stereo Enhancer is enabled |
| */ |
| if ((pInstance->Params.OperatingMode & LVCS_STEREOENHANCESWITCH) != 0) { |
| /* |
| * Convert from stereo to middle and side |
| */ |
| if (NumChannels == 1) { |
| // Copy same input to scratch as Middle data |
| Copy_Float((LVM_FLOAT*)pInData, (LVM_FLOAT*)pScratch, (LVM_INT16)NumSamples); |
| } else { |
| From2iToMS_Float(pInData, pScratch, pScratch + NumSamples, (LVM_INT16)NumSamples); |
| } |
| |
| /* |
| * Apply filter to the middle signal |
| */ |
| if (pInstance->OutputDevice == LVCS_HEADPHONE) { |
| pInstance->pSEMidBiquad->process(pScratch, pScratch, NumSamples); |
| } else { |
| Mult3s_Float(pScratch, /* Source */ |
| (LVM_FLOAT)pConfig->MidGain, /* Gain */ |
| pScratch, /* Destination */ |
| (LVM_INT16)NumSamples); /* Number of samples */ |
| } |
| |
| /* |
| * Apply the filter the side signal only in stereo mode for headphones |
| * and in all modes for mobile speakers |
| */ |
| if (pInstance->Params.SourceFormat == LVCS_STEREO) { |
| pInstance->pSESideBiquad->process(pScratch + NumSamples, pScratch + NumSamples, |
| NumSamples); |
| } |
| |
| if (NumChannels == 1) { |
| // Copy processed Middle data from scratch to pOutData |
| Copy_Float((LVM_FLOAT*)pScratch, (LVM_FLOAT*)pOutData, (LVM_INT16)NumSamples); |
| } else { |
| /* |
| * Convert from middle and side to stereo |
| */ |
| MSTo2i_Sat_Float(pScratch, pScratch + NumSamples, pOutData, (LVM_INT16)NumSamples); |
| } |
| |
| } else { |
| /* |
| * The stereo enhancer is disabled so just copy the data |
| */ |
| Copy_Float((LVM_FLOAT*)pInData, /* Source */ |
| (LVM_FLOAT*)pOutData, /* Destination */ |
| (LVM_INT16)destNumSamples); /* Number of frames */ |
| } |
| |
| return (LVCS_SUCCESS); |
| } |
