diff options
Diffstat (limited to 'media/libeffects/downmix/EffectDownmix.c')
-rw-r--r-- | media/libeffects/downmix/EffectDownmix.c | 889 |
1 files changed, 889 insertions, 0 deletions
diff --git a/media/libeffects/downmix/EffectDownmix.c b/media/libeffects/downmix/EffectDownmix.c new file mode 100644 index 0000000..a325172 --- /dev/null +++ b/media/libeffects/downmix/EffectDownmix.c @@ -0,0 +1,889 @@ +/* + * Copyright (C) 2012 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. + */ + +#define LOG_TAG "EffectDownmix" +#define LOG_NDEBUG 0 +#include <cutils/log.h> +#include <stdlib.h> +#include <string.h> +#include <stdbool.h> +#include "EffectDownmix.h" + +#define MINUS_3_DB_IN_Q19_12 2896 // -3dB = 0.707 * 2^12 = 2896 + +// effect_handle_t interface implementation for downmix effect +const struct effect_interface_s gDownmixInterface = { + Downmix_Process, + Downmix_Command, + Downmix_GetDescriptor, + NULL /* no process_reverse function, no reference stream needed */ +}; + +audio_effect_library_t AUDIO_EFFECT_LIBRARY_INFO_SYM = { + tag : AUDIO_EFFECT_LIBRARY_TAG, + version : EFFECT_LIBRARY_API_VERSION, + name : "Downmix Library", + implementor : "The Android Open Source Project", + query_num_effects : DownmixLib_QueryNumberEffects, + query_effect : DownmixLib_QueryEffect, + create_effect : DownmixLib_Create, + release_effect : DownmixLib_Release, + get_descriptor : DownmixLib_GetDescriptor, +}; + + +// AOSP insert downmix UUID: 93f04452-e4fe-41cc-91f9-e475b6d1d69f +static const effect_descriptor_t gDownmixDescriptor = { + EFFECT_UIID_DOWNMIX__, //type + {0x93f04452, 0xe4fe, 0x41cc, 0x91f9, {0xe4, 0x75, 0xb6, 0xd1, 0xd6, 0x9f}}, // uuid + EFFECT_CONTROL_API_VERSION, + EFFECT_FLAG_TYPE_INSERT | EFFECT_FLAG_INSERT_FIRST, + 0, //FIXME what value should be reported? // cpu load + 0, //FIXME what value should be reported? // memory usage + "Multichannel Downmix To Stereo", // human readable effect name + "The Android Open Source Project" // human readable effect implementor name +}; + +// gDescriptors contains pointers to all defined effect descriptor in this library +static const effect_descriptor_t * const gDescriptors[] = { + &gDownmixDescriptor +}; + +// number of effects in this library +const int kNbEffects = sizeof(gDescriptors) / sizeof(const effect_descriptor_t *); + + +/*---------------------------------------------------------------------------- + * Effect API implementation + *--------------------------------------------------------------------------*/ + +/*--- Effect Library Interface Implementation ---*/ + +int32_t DownmixLib_QueryNumberEffects(uint32_t *pNumEffects) { + ALOGV("DownmixLib_QueryNumberEffects()"); + *pNumEffects = kNbEffects; + return 0; +} + +int32_t DownmixLib_QueryEffect(uint32_t index, effect_descriptor_t *pDescriptor) { + ALOGV("DownmixLib_QueryEffect() index=%d", index); + if (pDescriptor == NULL) { + return -EINVAL; + } + if (index >= (uint32_t)kNbEffects) { + return -EINVAL; + } + memcpy(pDescriptor, gDescriptors[index], sizeof(effect_descriptor_t)); + return 0; +} + + +int32_t DownmixLib_Create(const effect_uuid_t *uuid, + int32_t sessionId, + int32_t ioId, + effect_handle_t *pHandle) { + int ret; + int i; + downmix_module_t *module; + const effect_descriptor_t *desc; + + ALOGV("DownmixLib_Create()"); + + if (pHandle == NULL || uuid == NULL) { + return -EINVAL; + } + + for (i = 0 ; i < kNbEffects ; i++) { + desc = gDescriptors[i]; + if (memcmp(uuid, &desc->uuid, sizeof(effect_uuid_t)) == 0) { + break; + } + } + + if (i == kNbEffects) { + return -ENOENT; + } + + module = malloc(sizeof(downmix_module_t)); + + module->itfe = &gDownmixInterface; + + module->context.state = DOWNMIX_STATE_UNINITIALIZED; + + ret = Downmix_Init(module); + if (ret < 0) { + ALOGW("DownmixLib_Create() init failed"); + free(module); + return ret; + } + + *pHandle = (effect_handle_t) module; + + ALOGV("DownmixLib_Create() %p , size %d", module, sizeof(downmix_module_t)); + + return 0; +} + + +int32_t DownmixLib_Release(effect_handle_t handle) { + downmix_module_t *pDwmModule = (downmix_module_t *)handle; + + ALOGV("DownmixLib_Release() %p", handle); + if (handle == NULL) { + return -EINVAL; + } + + pDwmModule->context.state = DOWNMIX_STATE_UNINITIALIZED; + + free(pDwmModule); + return 0; +} + + +int32_t DownmixLib_GetDescriptor(const effect_uuid_t *uuid, effect_descriptor_t *pDescriptor) { + ALOGV("DownmixLib_GetDescriptor()"); + int i; + + if (pDescriptor == NULL || uuid == NULL){ + ALOGE("DownmixLib_Create() called with NULL pointer"); + return -EINVAL; + } + ALOGV("DownmixLib_GetDescriptor() nb effects=%d", kNbEffects); + for (i = 0; i < kNbEffects; i++) { + ALOGV("DownmixLib_GetDescriptor() i=%d", i); + if (memcmp(uuid, &gDescriptors[i]->uuid, sizeof(effect_uuid_t)) == 0) { + memcpy(pDescriptor, gDescriptors[i], sizeof(effect_descriptor_t)); + ALOGV("EffectGetDescriptor - UUID matched downmix type %d, UUID = %x", + i, gDescriptors[i]->uuid.timeLow); + return 0; + } + } + + return -EINVAL; +} + + +/*--- Effect Control Interface Implementation ---*/ + +static int Downmix_Process(effect_handle_t self, + audio_buffer_t *inBuffer, audio_buffer_t *outBuffer) { + + downmix_object_t *pDownmixer; + int16_t *pSrc, *pDst; + downmix_module_t *pDwmModule = (downmix_module_t *)self; + + if (pDwmModule == NULL) { + return -EINVAL; + } + + if (inBuffer == NULL || inBuffer->raw == NULL || + outBuffer == NULL || outBuffer->raw == NULL || + inBuffer->frameCount != outBuffer->frameCount) { + return -EINVAL; + } + + pDownmixer = (downmix_object_t*) &pDwmModule->context; + + if (pDownmixer->state == DOWNMIX_STATE_UNINITIALIZED) { + ALOGE("Downmix_Process error: trying to use an uninitialized downmixer"); + return -EINVAL; + } else if (pDownmixer->state == DOWNMIX_STATE_INITIALIZED) { + ALOGE("Downmix_Process error: trying to use a non-configured downmixer"); + return -ENODATA; + } + + pSrc = inBuffer->s16; + pDst = outBuffer->s16; + size_t numFrames = outBuffer->frameCount; + + const bool accumulate = + (pDwmModule->config.outputCfg.accessMode == EFFECT_BUFFER_ACCESS_ACCUMULATE); + + switch(pDownmixer->type) { + + case DOWNMIX_TYPE_STRIP: + if (accumulate) { + while (numFrames) { + pDst[0] = clamp16(pDst[0] + pSrc[0]); + pDst[1] = clamp16(pDst[1] + pSrc[1]); + pSrc += pDownmixer->input_channel_count; + pDst += 2; + numFrames--; + } + } else { + while (numFrames) { + pDst[0] = pSrc[0]; + pDst[1] = pSrc[1]; + pSrc += pDownmixer->input_channel_count; + pDst += 2; + numFrames--; + } + } + break; + + case DOWNMIX_TYPE_FOLD: + // optimize for the common formats + switch(pDwmModule->config.inputCfg.channels) { + case AUDIO_CHANNEL_OUT_QUAD: + Downmix_foldFromQuad(pSrc, pDst, numFrames, accumulate); + break; + case AUDIO_CHANNEL_OUT_SURROUND: + Downmix_foldFromSurround(pSrc, pDst, numFrames, accumulate); + break; + case AUDIO_CHANNEL_OUT_5POINT1: + Downmix_foldFrom5Point1(pSrc, pDst, numFrames, accumulate); + break; + case AUDIO_CHANNEL_OUT_7POINT1: + Downmix_foldFrom7Point1(pSrc, pDst, numFrames, accumulate); + break; + default: + // FIXME implement generic downmix + ALOGE("Multichannel configurations other than quad, 4.0, 5.1 and 7.1 are not supported"); + break; + } + break; + + default: + return -EINVAL; + } + + return 0; +} + + +static int Downmix_Command(effect_handle_t self, uint32_t cmdCode, uint32_t cmdSize, + void *pCmdData, uint32_t *replySize, void *pReplyData) { + + downmix_module_t *pDwmModule = (downmix_module_t *) self; + downmix_object_t *pDownmixer; + int retsize; + + if (pDwmModule == NULL || pDwmModule->context.state == DOWNMIX_STATE_UNINITIALIZED) { + return -EINVAL; + } + + pDownmixer = (downmix_object_t*) &pDwmModule->context; + + ALOGV("Downmix_Command command %d cmdSize %d",cmdCode, cmdSize); + + switch (cmdCode) { + case EFFECT_CMD_INIT: + if (pReplyData == NULL || *replySize != sizeof(int)) { + return -EINVAL; + } + *(int *) pReplyData = Downmix_Init(pDwmModule); + break; + + case EFFECT_CMD_SET_CONFIG: + if (pCmdData == NULL || cmdSize != sizeof(effect_config_t) + || pReplyData == NULL || *replySize != sizeof(int)) { + return -EINVAL; + } + *(int *) pReplyData = Downmix_Configure(pDwmModule, + (effect_config_t *)pCmdData, false); + break; + + case EFFECT_CMD_RESET: + Downmix_Reset(pDownmixer, false); + break; + + case EFFECT_CMD_GET_PARAM: + ALOGV("Downmix_Command EFFECT_CMD_GET_PARAM pCmdData %p, *replySize %d, pReplyData: %p", + pCmdData, *replySize, pReplyData); + if (pCmdData == NULL || cmdSize < (int)(sizeof(effect_param_t) + sizeof(int32_t)) || + pReplyData == NULL || + *replySize < (int) sizeof(effect_param_t) + 2 * sizeof(int32_t)) { + return -EINVAL; + } + effect_param_t *rep = (effect_param_t *) pReplyData; + memcpy(pReplyData, pCmdData, sizeof(effect_param_t) + sizeof(int32_t)); + ALOGV("Downmix_Command EFFECT_CMD_GET_PARAM param %d, replySize %d", + *(int32_t *)rep->data, rep->vsize); + rep->status = Downmix_getParameter(pDownmixer, *(int32_t *)rep->data, &rep->vsize, + rep->data + sizeof(int32_t)); + *replySize = sizeof(effect_param_t) + sizeof(int32_t) + rep->vsize; + break; + + case EFFECT_CMD_SET_PARAM: + ALOGV("Downmix_Command EFFECT_CMD_SET_PARAM cmdSize %d pCmdData %p, *replySize %d, " \ + "pReplyData %p", cmdSize, pCmdData, *replySize, pReplyData); + if (pCmdData == NULL || (cmdSize < (int)(sizeof(effect_param_t) + sizeof(int32_t))) + || pReplyData == NULL || *replySize != (int)sizeof(int32_t)) { + return -EINVAL; + } + effect_param_t *cmd = (effect_param_t *) pCmdData; + *(int *)pReplyData = Downmix_setParameter(pDownmixer, *(int32_t *)cmd->data, + cmd->vsize, cmd->data + sizeof(int32_t)); + break; + + case EFFECT_CMD_SET_PARAM_DEFERRED: + //FIXME implement + ALOGW("Downmix_Command command EFFECT_CMD_SET_PARAM_DEFERRED not supported, FIXME"); + break; + + case EFFECT_CMD_SET_PARAM_COMMIT: + //FIXME implement + ALOGW("Downmix_Command command EFFECT_CMD_SET_PARAM_COMMIT not supported, FIXME"); + break; + + case EFFECT_CMD_ENABLE: + if (pReplyData == NULL || *replySize != sizeof(int)) { + return -EINVAL; + } + if (pDownmixer->state != DOWNMIX_STATE_INITIALIZED) { + return -ENOSYS; + } + pDownmixer->state = DOWNMIX_STATE_ACTIVE; + ALOGV("EFFECT_CMD_ENABLE() OK"); + *(int *)pReplyData = 0; + break; + + case EFFECT_CMD_DISABLE: + if (pReplyData == NULL || *replySize != sizeof(int)) { + return -EINVAL; + } + if (pDownmixer->state != DOWNMIX_STATE_ACTIVE) { + return -ENOSYS; + } + pDownmixer->state = DOWNMIX_STATE_INITIALIZED; + ALOGV("EFFECT_CMD_DISABLE() OK"); + *(int *)pReplyData = 0; + break; + + case EFFECT_CMD_SET_DEVICE: + if (pCmdData == NULL || cmdSize != (int)sizeof(uint32_t)) { + return -EINVAL; + } + // FIXME change type if playing on headset vs speaker + ALOGV("Downmix_Command EFFECT_CMD_SET_DEVICE: 0x%08x", *(uint32_t *)pCmdData); + break; + + case EFFECT_CMD_SET_VOLUME: { + // audio output is always stereo => 2 channel volumes + if (pCmdData == NULL || cmdSize != (int)sizeof(uint32_t) * 2) { + return -EINVAL; + } + // FIXME change volume + ALOGW("Downmix_Command command EFFECT_CMD_SET_VOLUME not supported, FIXME"); + float left = (float)(*(uint32_t *)pCmdData) / (1 << 24); + float right = (float)(*((uint32_t *)pCmdData + 1)) / (1 << 24); + ALOGV("Downmix_Command EFFECT_CMD_SET_VOLUME: left %f, right %f ", left, right); + break; + } + + case EFFECT_CMD_SET_AUDIO_MODE: + if (pCmdData == NULL || cmdSize != (int)sizeof(uint32_t)) { + return -EINVAL; + } + ALOGV("Downmix_Command EFFECT_CMD_SET_AUDIO_MODE: %d", *(uint32_t *)pCmdData); + break; + + case EFFECT_CMD_SET_CONFIG_REVERSE: + case EFFECT_CMD_SET_INPUT_DEVICE: + // these commands are ignored by a downmix effect + break; + + default: + ALOGW("Downmix_Command invalid command %d",cmdCode); + return -EINVAL; + } + + return 0; +} + + +int Downmix_GetDescriptor(effect_handle_t self, effect_descriptor_t *pDescriptor) +{ + downmix_module_t *pDwnmxModule = (downmix_module_t *) self; + + if (pDwnmxModule == NULL || + pDwnmxModule->context.state == DOWNMIX_STATE_UNINITIALIZED) { + return -EINVAL; + } + + memcpy(pDescriptor, &gDownmixDescriptor, sizeof(effect_descriptor_t)); + + return 0; +} + + +/*---------------------------------------------------------------------------- + * Downmix internal functions + *--------------------------------------------------------------------------*/ + +/*---------------------------------------------------------------------------- + * Downmix_Init() + *---------------------------------------------------------------------------- + * Purpose: + * Initialize downmix context and apply default parameters + * + * Inputs: + * pDwmModule pointer to downmix effect module + * + * Outputs: + * + * Returns: + * 0 indicates success + * + * Side Effects: + * updates: + * pDwmModule->context.type + * pDwmModule->context.apply_volume_correction + * pDwmModule->config.inputCfg + * pDwmModule->config.outputCfg + * pDwmModule->config.inputCfg.samplingRate + * pDwmModule->config.outputCfg.samplingRate + * pDwmModule->context.state + * doesn't set: + * pDwmModule->itfe + * + *---------------------------------------------------------------------------- + */ + +int Downmix_Init(downmix_module_t *pDwmModule) { + + ALOGV("Downmix_Init module %p", pDwmModule); + int ret = 0; + + memset(&pDwmModule->context, 0, sizeof(downmix_object_t)); + + pDwmModule->config.inputCfg.accessMode = EFFECT_BUFFER_ACCESS_READ; + pDwmModule->config.inputCfg.format = AUDIO_FORMAT_PCM_16_BIT; + pDwmModule->config.inputCfg.channels = AUDIO_CHANNEL_OUT_7POINT1; + pDwmModule->config.inputCfg.bufferProvider.getBuffer = NULL; + pDwmModule->config.inputCfg.bufferProvider.releaseBuffer = NULL; + pDwmModule->config.inputCfg.bufferProvider.cookie = NULL; + pDwmModule->config.inputCfg.mask = EFFECT_CONFIG_ALL; + + pDwmModule->config.inputCfg.samplingRate = 44100; + pDwmModule->config.outputCfg.samplingRate = pDwmModule->config.inputCfg.samplingRate; + + // set a default value for the access mode, but should be overwritten by caller + pDwmModule->config.outputCfg.accessMode = EFFECT_BUFFER_ACCESS_ACCUMULATE; + pDwmModule->config.outputCfg.format = AUDIO_FORMAT_PCM_16_BIT; + pDwmModule->config.outputCfg.channels = AUDIO_CHANNEL_OUT_STEREO; + pDwmModule->config.outputCfg.bufferProvider.getBuffer = NULL; + pDwmModule->config.outputCfg.bufferProvider.releaseBuffer = NULL; + pDwmModule->config.outputCfg.bufferProvider.cookie = NULL; + pDwmModule->config.outputCfg.mask = EFFECT_CONFIG_ALL; + + ret = Downmix_Configure(pDwmModule, &pDwmModule->config, true); + if (ret != 0) { + ALOGV("Downmix_Init error %d on module %p", ret, pDwmModule); + } else { + pDwmModule->context.state = DOWNMIX_STATE_INITIALIZED; + } + + return ret; +} + + +/*---------------------------------------------------------------------------- + * Downmix_Configure() + *---------------------------------------------------------------------------- + * Purpose: + * Set input and output audio configuration. + * + * Inputs: + * pDwmModule pointer to downmix effect module + * pConfig pointer to effect_config_t structure containing input + * and output audio parameters configuration + * init true if called from init function + * + * Outputs: + * + * Returns: + * 0 indicates success + * + * Side Effects: + * + *---------------------------------------------------------------------------- + */ + +int Downmix_Configure(downmix_module_t *pDwmModule, effect_config_t *pConfig, bool init) { + + downmix_object_t *pDownmixer = &pDwmModule->context; + + // Check configuration compatibility with build options, and effect capabilities + if (pConfig->inputCfg.samplingRate != pConfig->outputCfg.samplingRate + || pConfig->outputCfg.channels != DOWNMIX_OUTPUT_CHANNELS + || pConfig->inputCfg.format != AUDIO_FORMAT_PCM_16_BIT + || pConfig->outputCfg.format != AUDIO_FORMAT_PCM_16_BIT) { + ALOGE("Downmix_Configure error: invalid config"); + return -EINVAL; + } + + memcpy(&pDwmModule->config, pConfig, sizeof(effect_config_t)); + + if (init) { + pDownmixer->type = DOWNMIX_TYPE_FOLD; + pDownmixer->apply_volume_correction = false; + pDownmixer->input_channel_count = 8; // matches default input of AUDIO_CHANNEL_OUT_7POINT1 + } else { + // when configuring the effect, do not allow a blank channel mask + if (pConfig->inputCfg.channels == 0) { + ALOGE("Downmix_Configure error: input channel mask can't be 0"); + return -EINVAL; + } + pDownmixer->input_channel_count = popcount(pConfig->inputCfg.channels); + } + + Downmix_Reset(pDownmixer, init); + + return 0; +} + + +/*---------------------------------------------------------------------------- + * Downmix_Reset() + *---------------------------------------------------------------------------- + * Purpose: + * Reset internal states. + * + * Inputs: + * pDownmixer pointer to downmix context + * init true if called from init function + * + * Outputs: +* + * Returns: + * 0 indicates success + * + * Side Effects: + * + *---------------------------------------------------------------------------- + */ + +int Downmix_Reset(downmix_object_t *pDownmixer, bool init) { + // nothing to do here + return 0; +} + + +/*---------------------------------------------------------------------------- + * Downmix_setParameter() + *---------------------------------------------------------------------------- + * Purpose: + * Set a Downmix parameter + * + * Inputs: + * pDownmixer handle to instance data + * param parameter + * pValue pointer to parameter value + * size value size + * + * Outputs: + * + * Returns: + * 0 indicates success + * + * Side Effects: + * + *---------------------------------------------------------------------------- + */ +int Downmix_setParameter(downmix_object_t *pDownmixer, int32_t param, size_t size, void *pValue) { + + int16_t value16; + ALOGV("Downmix_setParameter, context %p, param %d, value16 %d, value32 %d", + pDownmixer, param, *(int16_t *)pValue, *(int32_t *)pValue); + + switch (param) { + + case DOWNMIX_PARAM_TYPE: + if (size != sizeof(downmix_type_t)) { + ALOGE("Downmix_setParameter(DOWNMIX_PARAM_TYPE) invalid size %d, should be %d", + size, sizeof(downmix_type_t)); + return -EINVAL; + } + value16 = *(int16_t *)pValue; + ALOGV("set DOWNMIX_PARAM_TYPE, type %d", value16); + if (!((value16 > DOWNMIX_TYPE_INVALID) && (value16 < DOWNMIX_TYPE_LAST))) { + ALOGE("Downmix_setParameter invalid DOWNMIX_PARAM_TYPE value %d", value16); + return -EINVAL; + } else { + pDownmixer->type = (downmix_type_t) value16; + break; + + default: + ALOGE("Downmix_setParameter unknown parameter %d", param); + return -EINVAL; + } +} + + return 0; +} /* end Downmix_setParameter */ + + +/*---------------------------------------------------------------------------- + * Downmix_getParameter() + *---------------------------------------------------------------------------- + * Purpose: + * Get a Downmix parameter + * + * Inputs: + * pDownmixer handle to instance data + * param parameter + * pValue pointer to variable to hold retrieved value + * pSize pointer to value size: maximum size as input + * + * Outputs: + * *pValue updated with parameter value + * *pSize updated with actual value size + * + * Returns: + * 0 indicates success + * + * Side Effects: + * + *---------------------------------------------------------------------------- + */ +int Downmix_getParameter(downmix_object_t *pDownmixer, int32_t param, size_t *pSize, void *pValue) { + int16_t *pValue16; + + switch (param) { + + case DOWNMIX_PARAM_TYPE: + if (*pSize < sizeof(int16_t)) { + ALOGE("Downmix_getParameter invalid parameter size %d for DOWNMIX_PARAM_TYPE", *pSize); + return -EINVAL; + } + pValue16 = (int16_t *)pValue; + *pValue16 = (int16_t) pDownmixer->type; + *pSize = sizeof(int16_t); + ALOGV("Downmix_getParameter DOWNMIX_PARAM_TYPE is %d", *pValue16); + break; + + default: + ALOGE("Downmix_getParameter unknown parameter %d", param); + return -EINVAL; + } + + return 0; +} /* end Downmix_getParameter */ + + +/*---------------------------------------------------------------------------- + * Downmix_foldFromQuad() + *---------------------------------------------------------------------------- + * Purpose: + * downmix a quad signal to stereo + * + * Inputs: + * pSrc quad audio samples to downmix + * numFrames the number of quad frames to downmix + * + * Outputs: + * pDst downmixed stereo audio samples + * + *---------------------------------------------------------------------------- + */ +void Downmix_foldFromQuad(int16_t *pSrc, int16_t*pDst, size_t numFrames, bool accumulate) { + // sample at index 0 is FL + // sample at index 1 is FR + // sample at index 2 is RL + // sample at index 3 is RR + if (accumulate) { + while (numFrames) { + // FL + RL + pDst[0] = clamp16(pDst[0] + pSrc[0] + pSrc[2]); + // FR + RR + pDst[1] = clamp16(pDst[1] + pSrc[1] + pSrc[3]); + pSrc += 4; + pDst += 2; + numFrames--; + } + } else { // same code as above but without adding and clamping pDst[i] to itself + while (numFrames) { + // FL + RL + pDst[0] = clamp16(pSrc[0] + pSrc[2]); + // FR + RR + pDst[1] = clamp16(pSrc[1] + pSrc[3]); + pSrc += 4; + pDst += 2; + numFrames--; + } + } +} + + +/*---------------------------------------------------------------------------- + * Downmix_foldFromSurround() + *---------------------------------------------------------------------------- + * Purpose: + * downmix a "surround sound" (mono rear) signal to stereo + * + * Inputs: + * pSrc surround signal to downmix + * numFrames the number of surround frames to downmix + * + * Outputs: + * pDst downmixed stereo audio samples + * + *---------------------------------------------------------------------------- + */ +void Downmix_foldFromSurround(int16_t *pSrc, int16_t*pDst, size_t numFrames, bool accumulate) { + int32_t lt, rt, centerPlusRearContrib; // samples in Q19.12 format + // sample at index 0 is FL + // sample at index 1 is FR + // sample at index 2 is FC + // sample at index 3 is RC + if (accumulate) { + while (numFrames) { + // centerPlusRearContrib = FC(-3dB) + RC(-3dB) + centerPlusRearContrib = (pSrc[2] * MINUS_3_DB_IN_Q19_12) + (pSrc[3] * MINUS_3_DB_IN_Q19_12); + // FL + centerPlusRearContrib + lt = (pSrc[0] << 12) + centerPlusRearContrib; + // FR + centerPlusRearContrib + rt = (pSrc[1] << 12) + centerPlusRearContrib; + pDst[0] = clamp16(pDst[0] + (lt >> 12)); + pDst[1] = clamp16(pDst[1] + (rt >> 12)); + pSrc += 4; + pDst += 2; + numFrames--; + } + } else { // same code as above but without adding and clamping pDst[i] to itself + while (numFrames) { + // centerPlusRearContrib = FC(-3dB) + RC(-3dB) + centerPlusRearContrib = (pSrc[2] * MINUS_3_DB_IN_Q19_12) + (pSrc[3] * MINUS_3_DB_IN_Q19_12); + // FL + centerPlusRearContrib + lt = (pSrc[0] << 12) + centerPlusRearContrib; + // FR + centerPlusRearContrib + rt = (pSrc[1] << 12) + centerPlusRearContrib; + pDst[0] = clamp16(lt >> 12); + pDst[1] = clamp16(rt >> 12); + pSrc += 4; + pDst += 2; + numFrames--; + } + } +} + + +/*---------------------------------------------------------------------------- + * Downmix_foldFrom5Point1() + *---------------------------------------------------------------------------- + * Purpose: + * downmix a 5.1 signal to stereo + * + * Inputs: + * pSrc 5.1 audio samples to downmix + * numFrames the number of 5.1 frames to downmix + * + * Outputs: + * pDst downmixed stereo audio samples + * + *---------------------------------------------------------------------------- + */ +void Downmix_foldFrom5Point1(int16_t *pSrc, int16_t*pDst, size_t numFrames, bool accumulate) { + int32_t lt, rt, centerPlusLfeContrib; // samples in Q19.12 format + // sample at index 0 is FL + // sample at index 1 is FR + // sample at index 2 is FC + // sample at index 3 is LFE + // sample at index 4 is RL + // sample at index 5 is RR + if (accumulate) { + while (numFrames) { + // centerPlusLfeContrib = FC(-3dB) + LFE(-3dB) + centerPlusLfeContrib = (pSrc[2] * MINUS_3_DB_IN_Q19_12) + + (pSrc[3] * MINUS_3_DB_IN_Q19_12); + // FL + centerPlusLfeContrib + RL + lt = (pSrc[0] << 12) + centerPlusLfeContrib + (pSrc[4] << 12); + // FR + centerPlusLfeContrib + RR + rt = (pSrc[1] << 12) + centerPlusLfeContrib + (pSrc[5] << 12); + pDst[0] = clamp16(pDst[0] + (lt >> 12)); + pDst[1] = clamp16(pDst[1] + (rt >> 12)); + pSrc += 6; + pDst += 2; + numFrames--; + } + } else { // same code as above but without adding and clamping pDst[i] to itself + while (numFrames) { + // centerPlusLfeContrib = FC(-3dB) + LFE(-3dB) + centerPlusLfeContrib = (pSrc[2] * MINUS_3_DB_IN_Q19_12) + + (pSrc[3] * MINUS_3_DB_IN_Q19_12); + // FL + centerPlusLfeContrib + RL + lt = (pSrc[0] << 12) + centerPlusLfeContrib + (pSrc[4] << 12); + // FR + centerPlusLfeContrib + RR + rt = (pSrc[1] << 12) + centerPlusLfeContrib + (pSrc[5] << 12); + pDst[0] = clamp16(lt >> 12); + pDst[1] = clamp16(rt >> 12); + pSrc += 6; + pDst += 2; + numFrames--; + } + } +} + + +/*---------------------------------------------------------------------------- + * Downmix_foldFrom7Point1() + *---------------------------------------------------------------------------- + * Purpose: + * downmix a 7.1 signal to stereo + * + * Inputs: + * pSrc 7.1 audio samples to downmix + * numFrames the number of 7.1 frames to downmix + * + * Outputs: + * pDst downmixed stereo audio samples + * + *---------------------------------------------------------------------------- + */ +void Downmix_foldFrom7Point1(int16_t *pSrc, int16_t*pDst, size_t numFrames, bool accumulate) { + int32_t lt, rt, centerPlusLfeContrib; // samples in Q19.12 format + // sample at index 0 is FL + // sample at index 1 is FR + // sample at index 2 is FC + // sample at index 3 is LFE + // sample at index 4 is RL + // sample at index 5 is RR + // sample at index 6 is SL + // sample at index 7 is SR + if (accumulate) { + while (numFrames) { + // centerPlusLfeContrib = FC(-3dB) + LFE(-3dB) + centerPlusLfeContrib = (pSrc[2] * MINUS_3_DB_IN_Q19_12) + + (pSrc[3] * MINUS_3_DB_IN_Q19_12); + // FL + centerPlusLfeContrib + SL + RL + lt = (pSrc[0] << 12) + centerPlusLfeContrib + (pSrc[6] << 12) + (pSrc[4] << 12); + // FR + centerPlusLfeContrib + SR + RR + rt = (pSrc[1] << 12) + centerPlusLfeContrib + (pSrc[7] << 12) + (pSrc[5] << 12); + pDst[0] = clamp16(lt >> 12); + pDst[1] = clamp16(rt >> 12); + pSrc += 8; + pDst += 2; + numFrames--; + } + } else { // same code as above but without adding and clamping pDst[i] to itself + while (numFrames) { + // centerPlusLfeContrib = FC(-3dB) + LFE(-3dB) + centerPlusLfeContrib = (pSrc[2] * MINUS_3_DB_IN_Q19_12) + + (pSrc[3] * MINUS_3_DB_IN_Q19_12); + // FL + centerPlusLfeContrib + SL + RL + lt = (pSrc[0] << 12) + centerPlusLfeContrib + (pSrc[6] << 12) + (pSrc[4] << 12); + // FR + centerPlusLfeContrib + SR + RR + rt = (pSrc[1] << 12) + centerPlusLfeContrib + (pSrc[7] << 12) + (pSrc[5] << 12); + pDst[0] = clamp16(pDst[0] + (lt >> 12)); + pDst[1] = clamp16(pDst[1] + (rt >> 12)); + pSrc += 8; + pDst += 2; + numFrames--; + } + } +} + |