LoudnessEnhancer audio effect implementation
Implementation based on DRC effect, controlled by a
target gain.
The target gain is used to amplify the signal at
the input of the DRC, and to compute the knee
of the DRC.
Bug 8413913
Change-Id: I386d64793a9fa3f7218e053d6f0a99f6836c02bd
diff --git a/media/libeffects/data/audio_effects.conf b/media/libeffects/data/audio_effects.conf
index 69a3c53..c3c4b67 100644
--- a/media/libeffects/data/audio_effects.conf
+++ b/media/libeffects/data/audio_effects.conf
@@ -35,6 +35,9 @@
downmix {
path /system/lib/soundfx/libdownmix.so
}
+ loudness_enhancer {
+ path /system/lib/soundfx/libldnhncr.so
+ }
}
# Default pre-processing library. Add to audio_effect.conf "libraries" section if
@@ -122,6 +125,10 @@
library downmix
uuid 93f04452-e4fe-41cc-91f9-e475b6d1d69f
}
+ loudness_enhancer {
+ library loudness_enhancer
+ uuid fa415329-2034-4bea-b5dc-5b381c8d1e2c
+ }
}
# Default pre-processing effects. Add to audio_effect.conf "effects" section if
diff --git a/media/libeffects/loudness/Android.mk b/media/libeffects/loudness/Android.mk
new file mode 100644
index 0000000..dcb7b27
--- /dev/null
+++ b/media/libeffects/loudness/Android.mk
@@ -0,0 +1,27 @@
+LOCAL_PATH:= $(call my-dir)
+
+# LoudnessEnhancer library
+include $(CLEAR_VARS)
+
+LOCAL_SRC_FILES:= \
+ EffectLoudnessEnhancer.cpp \
+ dsp/core/dynamic_range_compression.cpp
+
+LOCAL_CFLAGS+= -O2 -fvisibility=hidden
+
+LOCAL_SHARED_LIBRARIES := \
+ libcutils \
+ liblog \
+ libstlport
+
+LOCAL_MODULE_PATH := $(TARGET_OUT_SHARED_LIBRARIES)/soundfx
+LOCAL_MODULE:= libldnhncr
+
+LOCAL_C_INCLUDES := \
+ $(call include-path-for, audio-effects) \
+ bionic \
+ bionic/libstdc++/include \
+ external/stlport/stlport
+
+
+include $(BUILD_SHARED_LIBRARY)
diff --git a/media/libeffects/loudness/EffectLoudnessEnhancer.cpp b/media/libeffects/loudness/EffectLoudnessEnhancer.cpp
new file mode 100644
index 0000000..dfc25db
--- /dev/null
+++ b/media/libeffects/loudness/EffectLoudnessEnhancer.cpp
@@ -0,0 +1,474 @@
+/*
+ * Copyright (C) 2013 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 "EffectLE"
+//#define LOG_NDEBUG 0
+#include <cutils/log.h>
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+#include <new>
+#include <time.h>
+#include <math.h>
+#include <audio_effects/effect_loudnessenhancer.h>
+#include "dsp/core/dynamic_range_compression.h"
+
+extern "C" {
+
+// effect_handle_t interface implementation for LE effect
+extern const struct effect_interface_s gLEInterface;
+
+// AOSP Loudness Enhancer UUID: fa415329-2034-4bea-b5dc-5b381c8d1e2c
+const effect_descriptor_t gLEDescriptor = {
+ {0xfe3199be, 0xaed0, 0x413f, 0x87bb, {0x11, 0x26, 0x0e, 0xb6, 0x3c, 0xf1}}, // type
+ {0xfa415329, 0x2034, 0x4bea, 0xb5dc, {0x5b, 0x38, 0x1c, 0x8d, 0x1e, 0x2c}}, // uuid
+ EFFECT_CONTROL_API_VERSION,
+ (EFFECT_FLAG_TYPE_INSERT | EFFECT_FLAG_INSERT_FIRST),
+ 0, // TODO
+ 1,
+ "Loudness Enhancer",
+ "The Android Open Source Project",
+};
+
+enum le_state_e {
+ LOUDNESS_ENHANCER_STATE_UNINITIALIZED,
+ LOUDNESS_ENHANCER_STATE_INITIALIZED,
+ LOUDNESS_ENHANCER_STATE_ACTIVE,
+};
+
+struct LoudnessEnhancerContext {
+ const struct effect_interface_s *mItfe;
+ effect_config_t mConfig;
+ uint8_t mState;
+ int32_t mTargetGainmB;// target gain in mB
+ // in this implementation, there is no coupling between the compression on the left and right
+ // channels
+ le_fx::AdaptiveDynamicRangeCompression* mCompressorL;
+ le_fx::AdaptiveDynamicRangeCompression* mCompressorR;
+};
+
+//
+//--- Local functions (not directly used by effect interface)
+//
+
+void LE_reset(LoudnessEnhancerContext *pContext)
+{
+ ALOGV(" > LE_reset(%p)", pContext);
+
+ if ((pContext->mCompressorL != NULL) && (pContext->mCompressorR != NULL)) {
+ float targetAmp = pow(10, pContext->mTargetGainmB/2000.0f); // mB to linear amplification
+ ALOGV("LE_reset(): Target gain=%dmB <=> factor=%.2fX", pContext->mTargetGainmB, targetAmp);
+ pContext->mCompressorL->Initialize(targetAmp, pContext->mConfig.inputCfg.samplingRate);
+ pContext->mCompressorR->Initialize(targetAmp, pContext->mConfig.inputCfg.samplingRate);
+ } else {
+ ALOGE("LE_reset(%p): null compressors, can't apply target gain", pContext);
+ }
+}
+
+static inline int16_t clamp16(int32_t sample)
+{
+ if ((sample>>15) ^ (sample>>31))
+ sample = 0x7FFF ^ (sample>>31);
+ return sample;
+}
+
+//----------------------------------------------------------------------------
+// LE_setConfig()
+//----------------------------------------------------------------------------
+// Purpose: Set input and output audio configuration.
+//
+// Inputs:
+// pContext: effect engine context
+// pConfig: pointer to effect_config_t structure holding input and output
+// configuration parameters
+//
+// Outputs:
+//
+//----------------------------------------------------------------------------
+
+int LE_setConfig(LoudnessEnhancerContext *pContext, effect_config_t *pConfig)
+{
+ ALOGV("LE_setConfig(%p)", pContext);
+
+ if (pConfig->inputCfg.samplingRate != pConfig->outputCfg.samplingRate) return -EINVAL;
+ if (pConfig->inputCfg.channels != pConfig->outputCfg.channels) return -EINVAL;
+ if (pConfig->inputCfg.format != pConfig->outputCfg.format) return -EINVAL;
+ if (pConfig->inputCfg.channels != AUDIO_CHANNEL_OUT_STEREO) return -EINVAL;
+ if (pConfig->outputCfg.accessMode != EFFECT_BUFFER_ACCESS_WRITE &&
+ pConfig->outputCfg.accessMode != EFFECT_BUFFER_ACCESS_ACCUMULATE) return -EINVAL;
+ if (pConfig->inputCfg.format != AUDIO_FORMAT_PCM_16_BIT) return -EINVAL;
+
+ pContext->mConfig = *pConfig;
+
+ LE_reset(pContext);
+
+ return 0;
+}
+
+
+//----------------------------------------------------------------------------
+// LE_getConfig()
+//----------------------------------------------------------------------------
+// Purpose: Get input and output audio configuration.
+//
+// Inputs:
+// pContext: effect engine context
+// pConfig: pointer to effect_config_t structure holding input and output
+// configuration parameters
+//
+// Outputs:
+//
+//----------------------------------------------------------------------------
+
+void LE_getConfig(LoudnessEnhancerContext *pContext, effect_config_t *pConfig)
+{
+ *pConfig = pContext->mConfig;
+}
+
+
+//----------------------------------------------------------------------------
+// LE_init()
+//----------------------------------------------------------------------------
+// Purpose: Initialize engine with default configuration.
+//
+// Inputs:
+// pContext: effect engine context
+//
+// Outputs:
+//
+//----------------------------------------------------------------------------
+
+int LE_init(LoudnessEnhancerContext *pContext)
+{
+ ALOGV("LE_init(%p)", pContext);
+
+ pContext->mConfig.inputCfg.accessMode = EFFECT_BUFFER_ACCESS_READ;
+ pContext->mConfig.inputCfg.channels = AUDIO_CHANNEL_OUT_STEREO;
+ pContext->mConfig.inputCfg.format = AUDIO_FORMAT_PCM_16_BIT;
+ pContext->mConfig.inputCfg.samplingRate = 44100;
+ pContext->mConfig.inputCfg.bufferProvider.getBuffer = NULL;
+ pContext->mConfig.inputCfg.bufferProvider.releaseBuffer = NULL;
+ pContext->mConfig.inputCfg.bufferProvider.cookie = NULL;
+ pContext->mConfig.inputCfg.mask = EFFECT_CONFIG_ALL;
+ pContext->mConfig.outputCfg.accessMode = EFFECT_BUFFER_ACCESS_ACCUMULATE;
+ pContext->mConfig.outputCfg.channels = AUDIO_CHANNEL_OUT_STEREO;
+ pContext->mConfig.outputCfg.format = AUDIO_FORMAT_PCM_16_BIT;
+ pContext->mConfig.outputCfg.samplingRate = 44100;
+ pContext->mConfig.outputCfg.bufferProvider.getBuffer = NULL;
+ pContext->mConfig.outputCfg.bufferProvider.releaseBuffer = NULL;
+ pContext->mConfig.outputCfg.bufferProvider.cookie = NULL;
+ pContext->mConfig.outputCfg.mask = EFFECT_CONFIG_ALL;
+
+ pContext->mTargetGainmB = LOUDNESS_ENHANCER_DEFAULT_TARGET_GAIN_MB;
+ float targetAmp = pow(10, pContext->mTargetGainmB/2000.0f); // mB to linear amplification
+ ALOGV("LE_init(): Target gain=%dmB <=> factor=%.2fX", pContext->mTargetGainmB, targetAmp);
+
+ if (pContext->mCompressorL == NULL) {
+ pContext->mCompressorL = new le_fx::AdaptiveDynamicRangeCompression();
+ pContext->mCompressorL->Initialize(targetAmp, pContext->mConfig.inputCfg.samplingRate);
+ }
+ if (pContext->mCompressorR == NULL) {
+ pContext->mCompressorR = new le_fx::AdaptiveDynamicRangeCompression();
+ pContext->mCompressorR->Initialize(targetAmp, pContext->mConfig.inputCfg.samplingRate);
+ }
+
+ LE_setConfig(pContext, &pContext->mConfig);
+
+ return 0;
+}
+
+//
+//--- Effect Library Interface Implementation
+//
+
+int LELib_Create(const effect_uuid_t *uuid,
+ int32_t sessionId,
+ int32_t ioId,
+ effect_handle_t *pHandle) {
+ ALOGV("LELib_Create()");
+ int ret;
+ int i;
+
+ if (pHandle == NULL || uuid == NULL) {
+ return -EINVAL;
+ }
+
+ if (memcmp(uuid, &gLEDescriptor.uuid, sizeof(effect_uuid_t)) != 0) {
+ return -EINVAL;
+ }
+
+ LoudnessEnhancerContext *pContext = new LoudnessEnhancerContext;
+
+ pContext->mItfe = &gLEInterface;
+ pContext->mState = LOUDNESS_ENHANCER_STATE_UNINITIALIZED;
+
+ pContext->mCompressorL = NULL;
+ pContext->mCompressorR = NULL;
+ ret = LE_init(pContext);
+ if (ret < 0) {
+ ALOGW("LELib_Create() init failed");
+ delete pContext;
+ return ret;
+ }
+
+ *pHandle = (effect_handle_t)pContext;
+
+ pContext->mState = LOUDNESS_ENHANCER_STATE_INITIALIZED;
+
+ ALOGV(" LELib_Create context is %p", pContext);
+
+ return 0;
+
+}
+
+int LELib_Release(effect_handle_t handle) {
+ LoudnessEnhancerContext * pContext = (LoudnessEnhancerContext *)handle;
+
+ ALOGV("LELib_Release %p", handle);
+ if (pContext == NULL) {
+ return -EINVAL;
+ }
+ pContext->mState = LOUDNESS_ENHANCER_STATE_UNINITIALIZED;
+ if (pContext->mCompressorL != NULL) {
+ delete pContext->mCompressorL;
+ pContext->mCompressorL = NULL;
+ }
+ if (pContext->mCompressorR != NULL) {
+ delete pContext->mCompressorR;
+ pContext->mCompressorR = NULL;
+ }
+ delete pContext;
+
+ return 0;
+}
+
+int LELib_GetDescriptor(const effect_uuid_t *uuid,
+ effect_descriptor_t *pDescriptor) {
+
+ if (pDescriptor == NULL || uuid == NULL){
+ ALOGV("LELib_GetDescriptor() called with NULL pointer");
+ return -EINVAL;
+ }
+
+ if (memcmp(uuid, &gLEDescriptor.uuid, sizeof(effect_uuid_t)) == 0) {
+ *pDescriptor = gLEDescriptor;
+ return 0;
+ }
+
+ return -EINVAL;
+} /* end LELib_GetDescriptor */
+
+//
+//--- Effect Control Interface Implementation
+//
+int LE_process(
+ effect_handle_t self, audio_buffer_t *inBuffer, audio_buffer_t *outBuffer)
+{
+ LoudnessEnhancerContext * pContext = (LoudnessEnhancerContext *)self;
+
+ if (pContext == NULL) {
+ return -EINVAL;
+ }
+
+ if (inBuffer == NULL || inBuffer->raw == NULL ||
+ outBuffer == NULL || outBuffer->raw == NULL ||
+ inBuffer->frameCount != outBuffer->frameCount ||
+ inBuffer->frameCount == 0) {
+ return -EINVAL;
+ }
+
+ //ALOGV("LE about to process %d samples", inBuffer->frameCount);
+ uint16_t inIdx;
+ float inputAmp = pow(10, pContext->mTargetGainmB/2000.0f);
+ for (inIdx = 0 ; inIdx < inBuffer->frameCount ; inIdx++) {
+ inBuffer->s16[2*inIdx] = pContext->mCompressorL->Compress(
+ inputAmp * (float)inBuffer->s16[2*inIdx]);
+ inBuffer->s16[2*inIdx +1] = pContext->mCompressorR->Compress(
+ inputAmp * (float)inBuffer->s16[2*inIdx +1]);
+ }
+
+ if (inBuffer->raw != outBuffer->raw) {
+ if (pContext->mConfig.outputCfg.accessMode == EFFECT_BUFFER_ACCESS_ACCUMULATE) {
+ for (size_t i = 0; i < outBuffer->frameCount*2; i++) {
+ outBuffer->s16[i] = clamp16(outBuffer->s16[i] + inBuffer->s16[i]);
+ }
+ } else {
+ memcpy(outBuffer->raw, inBuffer->raw, outBuffer->frameCount * 2 * sizeof(int16_t));
+ }
+ }
+ if (pContext->mState != LOUDNESS_ENHANCER_STATE_ACTIVE) {
+ return -ENODATA;
+ }
+ return 0;
+}
+
+int LE_command(effect_handle_t self, uint32_t cmdCode, uint32_t cmdSize,
+ void *pCmdData, uint32_t *replySize, void *pReplyData) {
+
+ LoudnessEnhancerContext * pContext = (LoudnessEnhancerContext *)self;
+ int retsize;
+
+ if (pContext == NULL || pContext->mState == LOUDNESS_ENHANCER_STATE_UNINITIALIZED) {
+ return -EINVAL;
+ }
+
+// ALOGV("LE_command command %d cmdSize %d",cmdCode, cmdSize);
+ switch (cmdCode) {
+ case EFFECT_CMD_INIT:
+ if (pReplyData == NULL || *replySize != sizeof(int)) {
+ return -EINVAL;
+ }
+ *(int *) pReplyData = LE_init(pContext);
+ break;
+ case EFFECT_CMD_SET_CONFIG:
+ if (pCmdData == NULL || cmdSize != sizeof(effect_config_t)
+ || pReplyData == NULL || *replySize != sizeof(int)) {
+ return -EINVAL;
+ }
+ *(int *) pReplyData = LE_setConfig(pContext,
+ (effect_config_t *) pCmdData);
+ break;
+ case EFFECT_CMD_GET_CONFIG:
+ if (pReplyData == NULL ||
+ *replySize != sizeof(effect_config_t)) {
+ return -EINVAL;
+ }
+ LE_getConfig(pContext, (effect_config_t *)pReplyData);
+ break;
+ case EFFECT_CMD_RESET:
+ LE_reset(pContext);
+ break;
+ case EFFECT_CMD_ENABLE:
+ if (pReplyData == NULL || *replySize != sizeof(int)) {
+ return -EINVAL;
+ }
+ if (pContext->mState != LOUDNESS_ENHANCER_STATE_INITIALIZED) {
+ return -ENOSYS;
+ }
+ pContext->mState = LOUDNESS_ENHANCER_STATE_ACTIVE;
+ ALOGV("EFFECT_CMD_ENABLE() OK");
+ *(int *)pReplyData = 0;
+ break;
+ case EFFECT_CMD_DISABLE:
+ if (pReplyData == NULL || *replySize != sizeof(int)) {
+ return -EINVAL;
+ }
+ if (pContext->mState != LOUDNESS_ENHANCER_STATE_ACTIVE) {
+ return -ENOSYS;
+ }
+ pContext->mState = LOUDNESS_ENHANCER_STATE_INITIALIZED;
+ ALOGV("EFFECT_CMD_DISABLE() OK");
+ *(int *)pReplyData = 0;
+ break;
+ case EFFECT_CMD_GET_PARAM: {
+ if (pCmdData == NULL ||
+ cmdSize != (int)(sizeof(effect_param_t) + sizeof(uint32_t)) ||
+ pReplyData == NULL ||
+ *replySize < (int)(sizeof(effect_param_t) + sizeof(uint32_t) + sizeof(uint32_t))) {
+ return -EINVAL;
+ }
+ memcpy(pReplyData, pCmdData, sizeof(effect_param_t) + sizeof(uint32_t));
+ effect_param_t *p = (effect_param_t *)pReplyData;
+ p->status = 0;
+ *replySize = sizeof(effect_param_t) + sizeof(uint32_t);
+ if (p->psize != sizeof(uint32_t)) {
+ p->status = -EINVAL;
+ break;
+ }
+ switch (*(uint32_t *)p->data) {
+ case LOUDNESS_ENHANCER_PARAM_TARGET_GAIN_MB:
+ ALOGV("get target gain(mB) = %d", pContext->mTargetGainmB);
+ *((int32_t *)p->data + 1) = pContext->mTargetGainmB;
+ p->vsize = sizeof(int32_t);
+ *replySize += sizeof(int32_t);
+ break;
+ default:
+ p->status = -EINVAL;
+ }
+ } break;
+ case EFFECT_CMD_SET_PARAM: {
+ if (pCmdData == NULL ||
+ cmdSize != (int)(sizeof(effect_param_t) + sizeof(uint32_t) + sizeof(uint32_t)) ||
+ pReplyData == NULL || *replySize != sizeof(int32_t)) {
+ return -EINVAL;
+ }
+ *(int32_t *)pReplyData = 0;
+ effect_param_t *p = (effect_param_t *)pCmdData;
+ if (p->psize != sizeof(uint32_t) || p->vsize != sizeof(uint32_t)) {
+ *(int32_t *)pReplyData = -EINVAL;
+ break;
+ }
+ switch (*(uint32_t *)p->data) {
+ case LOUDNESS_ENHANCER_PARAM_TARGET_GAIN_MB:
+ pContext->mTargetGainmB = *((int32_t *)p->data + 1);
+ ALOGV("set target gain(mB) = %d", pContext->mTargetGainmB);
+ LE_reset(pContext); // apply parameter update
+ break;
+ default:
+ *(int32_t *)pReplyData = -EINVAL;
+ }
+ } break;
+ case EFFECT_CMD_SET_DEVICE:
+ case EFFECT_CMD_SET_VOLUME:
+ case EFFECT_CMD_SET_AUDIO_MODE:
+ break;
+
+ default:
+ ALOGW("LE_command invalid command %d",cmdCode);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/* Effect Control Interface Implementation: get_descriptor */
+int LE_getDescriptor(effect_handle_t self,
+ effect_descriptor_t *pDescriptor)
+{
+ LoudnessEnhancerContext * pContext = (LoudnessEnhancerContext *) self;
+
+ if (pContext == NULL || pDescriptor == NULL) {
+ ALOGV("LE_getDescriptor() invalid param");
+ return -EINVAL;
+ }
+
+ *pDescriptor = gLEDescriptor;
+
+ return 0;
+} /* end LE_getDescriptor */
+
+// effect_handle_t interface implementation for DRC effect
+const struct effect_interface_s gLEInterface = {
+ LE_process,
+ LE_command,
+ LE_getDescriptor,
+ NULL,
+};
+
+// This is the only symbol that needs to be exported
+__attribute__ ((visibility ("default")))
+audio_effect_library_t AUDIO_EFFECT_LIBRARY_INFO_SYM = {
+ tag : AUDIO_EFFECT_LIBRARY_TAG,
+ version : EFFECT_LIBRARY_API_VERSION,
+ name : "Loudness Enhancer Library",
+ implementor : "The Android Open Source Project",
+ create_effect : LELib_Create,
+ release_effect : LELib_Release,
+ get_descriptor : LELib_GetDescriptor,
+};
+
+}; // extern "C"
+
diff --git a/media/libeffects/loudness/MODULE_LICENSE_APACHE2 b/media/libeffects/loudness/MODULE_LICENSE_APACHE2
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/media/libeffects/loudness/MODULE_LICENSE_APACHE2
diff --git a/media/libeffects/loudness/NOTICE b/media/libeffects/loudness/NOTICE
new file mode 100644
index 0000000..ad6ed94
--- /dev/null
+++ b/media/libeffects/loudness/NOTICE
@@ -0,0 +1,190 @@
+
+ Copyright (c) 2013, 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.
+
+ 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.
+
+
+ Apache License
+ Version 2.0, January 2004
+ http://www.apache.org/licenses/
+
+ TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
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+
+ (b) You must cause any modified files to carry prominent notices
+ stating that You changed the files; and
+
+ (c) You must retain, in the Source form of any Derivative Works
+ that You distribute, all copyright, patent, trademark, and
+ attribution notices from the Source form of the Work,
+ excluding those notices that do not pertain to any part of
+ the Derivative Works; and
+
+ (d) If the Work includes a "NOTICE" text file as part of its
+ distribution, then any Derivative Works that You distribute must
+ include a readable copy of the attribution notices contained
+ within such NOTICE file, excluding those notices that do not
+ pertain to any part of the Derivative Works, in at least one
+ of the following places: within a NOTICE text file distributed
+ as part of the Derivative Works; within the Source form or
+ documentation, if provided along with the Derivative Works; or,
+ within a display generated by the Derivative Works, if and
+ wherever such third-party notices normally appear. The contents
+ of the NOTICE file are for informational purposes only and
+ do not modify the License. You may add Your own attribution
+ notices within Derivative Works that You distribute, alongside
+ or as an addendum to the NOTICE text from the Work, provided
+ that such additional attribution notices cannot be construed
+ as modifying the License.
+
+ You may add Your own copyright statement to Your modifications and
+ may provide additional or different license terms and conditions
+ for use, reproduction, or distribution of Your modifications, or
+ for any such Derivative Works as a whole, provided Your use,
+ reproduction, and distribution of the Work otherwise complies with
+ the conditions stated in this License.
+
+ 5. Submission of Contributions. Unless You explicitly state otherwise,
+ any Contribution intentionally submitted for inclusion in the Work
+ by You to the Licensor shall be under the terms and conditions of
+ this License, without any additional terms or conditions.
+ Notwithstanding the above, nothing herein shall supersede or modify
+ the terms of any separate license agreement you may have executed
+ with Licensor regarding such Contributions.
+
+ 6. Trademarks. This License does not grant permission to use the trade
+ names, trademarks, service marks, or product names of the Licensor,
+ except as required for reasonable and customary use in describing the
+ origin of the Work and reproducing the content of the NOTICE file.
+
+ 7. Disclaimer of Warranty. Unless required by applicable law or
+ agreed to in writing, Licensor provides the Work (and each
+ Contributor provides its Contributions) on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+ implied, including, without limitation, any warranties or conditions
+ of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+ PARTICULAR PURPOSE. You are solely responsible for determining the
+ appropriateness of using or redistributing the Work and assume any
+ risks associated with Your exercise of permissions under this License.
+
+ 8. Limitation of Liability. In no event and under no legal theory,
+ whether in tort (including negligence), contract, or otherwise,
+ unless required by applicable law (such as deliberate and grossly
+ negligent acts) or agreed to in writing, shall any Contributor be
+ liable to You for damages, including any direct, indirect, special,
+ incidental, or consequential damages of any character arising as a
+ result of this License or out of the use or inability to use the
+ Work (including but not limited to damages for loss of goodwill,
+ work stoppage, computer failure or malfunction, or any and all
+ other commercial damages or losses), even if such Contributor
+ has been advised of the possibility of such damages.
+
+ 9. Accepting Warranty or Additional Liability. While redistributing
+ the Work or Derivative Works thereof, You may choose to offer,
+ and charge a fee for, acceptance of support, warranty, indemnity,
+ or other liability obligations and/or rights consistent with this
+ License. However, in accepting such obligations, You may act only
+ on Your own behalf and on Your sole responsibility, not on behalf
+ of any other Contributor, and only if You agree to indemnify,
+ defend, and hold each Contributor harmless for any liability
+ incurred by, or claims asserted against, such Contributor by reason
+ of your accepting any such warranty or additional liability.
+
+ END OF TERMS AND CONDITIONS
+
diff --git a/media/libeffects/loudness/common/core/basic_types.h b/media/libeffects/loudness/common/core/basic_types.h
new file mode 100644
index 0000000..593e914
--- /dev/null
+++ b/media/libeffects/loudness/common/core/basic_types.h
@@ -0,0 +1,114 @@
+/*
+ * Copyright (C) 2013 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.
+ */
+
+#ifndef LE_FX_ENGINE_COMMON_CORE_BASIC_TYPES_H_
+#define LE_FX_ENGINE_COMMON_CORE_BASIC_TYPES_H_
+
+#include <stddef.h>
+#include <stdlib.h>
+#include <string>
+using ::std::string;
+using ::std::basic_string;
+#include <vector>
+using ::std::vector;
+
+#include "common/core/os.h"
+
+// -----------------------------------------------------------------------------
+// Definitions of common basic types:
+// -----------------------------------------------------------------------------
+
+#if !defined(G_COMPILE) && !defined(BASE_INTEGRAL_TYPES_H_)
+
+namespace le_fx {
+
+typedef signed char schar;
+typedef signed char int8;
+typedef short int16;
+typedef int int32;
+typedef long long int64;
+
+typedef unsigned char uint8;
+typedef unsigned short uint16;
+typedef unsigned int uint32;
+typedef unsigned long long uint64;
+
+} // namespace le_fx
+
+#endif
+
+namespace le_fx {
+
+struct FloatArray {
+ int length;
+ float *data;
+
+ FloatArray(void) {
+ data = NULL;
+ length = 0;
+ }
+};
+
+struct Int16Array {
+ int length;
+ int16 *data;
+
+ Int16Array(void) {
+ data = NULL;
+ length = 0;
+ }
+};
+
+struct Int32Array {
+ int length;
+ int32 *data;
+
+ Int32Array(void) {
+ data = NULL;
+ length = 0;
+ }
+};
+
+struct Int8Array {
+ int length;
+ uint8 *data;
+
+ Int8Array(void) {
+ data = NULL;
+ length = 0;
+ }
+};
+
+//
+// Simple wrapper for waveform data:
+//
+class WaveData : public vector<int16> {
+ public:
+ WaveData();
+ ~WaveData();
+
+ void Set(int number_samples, int sampling_rate, int16 *data);
+ int sample_rate(void) const;
+ void set_sample_rate(int sample_rate);
+ bool Equals(const WaveData &wave_data, int threshold = 0) const;
+
+ private:
+ int sample_rate_;
+};
+
+} // namespace le_fx
+
+#endif // LE_FX_ENGINE_COMMON_CORE_BASIC_TYPES_H_
diff --git a/media/libeffects/loudness/common/core/byte_swapper.h b/media/libeffects/loudness/common/core/byte_swapper.h
new file mode 100644
index 0000000..8f0caf3
--- /dev/null
+++ b/media/libeffects/loudness/common/core/byte_swapper.h
@@ -0,0 +1,151 @@
+/*
+ * Copyright (C) 2013 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.
+ */
+
+#ifndef LE_FX_ENGINE_COMMON_CORE_BYTE_SWAPPER_H_
+#define LE_FX_ENGINE_COMMON_CORE_BYTE_SWAPPER_H_
+
+#include <stdio.h>
+#include <string.h>
+
+#include "common/core/basic_types.h"
+#include "common/core/os.h"
+
+namespace le_fx {
+
+namespace arch {
+
+inline bool IsLittleEndian(void) {
+ int16 word = 1;
+ char *cp = reinterpret_cast<char *>(&word);
+ return cp[0] != 0;
+}
+
+inline bool IsBigEndian(void) {
+ return !IsLittleEndian();
+}
+
+template <typename T, unsigned int kValSize>
+struct ByteSwapper {
+ static T Swap(const T &val) {
+ T new_val = val;
+ char *first = &new_val, *last = first + kValSize - 1, x;
+ for (; first < last; ++first, --last) {
+ x = *last;
+ *last = *first;
+ *first = x;
+ }
+ return new_val;
+ }
+};
+
+template <typename T>
+struct ByteSwapper<T, 1> {
+ static T Swap(const T &val) {
+ return val;
+ }
+};
+
+template <typename T>
+struct ByteSwapper<T, 2> {
+ static T Swap(const T &val) {
+ T new_val;
+ const char *o = (const char *)&val;
+ char *p = reinterpret_cast<char *>(&new_val);
+ p[0] = o[1];
+ p[1] = o[0];
+ return new_val;
+ }
+};
+
+template <typename T>
+struct ByteSwapper<T, 4> {
+ static T Swap(const T &val) {
+ T new_val;
+ const char *o = (const char *)&val;
+ char *p = reinterpret_cast<char *>(&new_val);
+ p[0] = o[3];
+ p[1] = o[2];
+ p[2] = o[1];
+ p[3] = o[0];
+ return new_val;
+ }
+};
+
+template <typename T>
+struct ByteSwapper<T, 8> {
+ static T Swap(const T &val) {
+ T new_val = val;
+ const char *o = (const char *)&val;
+ char *p = reinterpret_cast<char *>(&new_val);
+ p[0] = o[7];
+ p[1] = o[6];
+ p[2] = o[5];
+ p[3] = o[4];
+ p[4] = o[3];
+ p[5] = o[2];
+ p[6] = o[1];
+ p[7] = o[0];
+ return new_val;
+ }
+};
+
+template <typename T>
+T SwapBytes(const T &val, bool force_swap) {
+ if (force_swap) {
+#if !defined(LE_FX__NEED_BYTESWAP)
+ return ByteSwapper<T, sizeof(T)>::Swap(val);
+#else
+ return val;
+#endif // !LE_FX_NEED_BYTESWAP
+ } else {
+#if !defined(LE_FX_NEED_BYTESWAP)
+ return val;
+#else
+ return ByteSwapper<T, sizeof(T)>::Swap(val);
+#endif // !LE_FX_NEED_BYTESWAP
+ }
+}
+
+template <typename T>
+const T *SwapBytes(const T *vals, unsigned int num_items, bool force_swap) {
+ if (force_swap) {
+#if !defined(LE_FX_NEED_BYTESWAP)
+ T *writeable_vals = const_cast<T *>(vals);
+ for (unsigned int i = 0; i < num_items; i++) {
+ writeable_vals[i] = ByteSwapper<T, sizeof(T)>::Swap(vals[i]);
+ }
+ return writeable_vals;
+#else
+ return vals;
+#endif // !LE_FX_NEED_BYTESWAP
+ } else {
+#if !defined(LE_FX_NEED_BYTESWAP)
+ return vals;
+#else
+ T *writeable_vals = const_cast<T *>(vals);
+ for (unsigned int i = 0; i < num_items; i++) {
+ writeable_vals[i] = ByteSwapper<T, sizeof(T)>::Swap(vals[i]);
+ }
+ return writeable_vals;
+#endif // !LE_FX_NEED_BYTESWAP
+ }
+}
+
+} // namespace arch
+
+} // namespace le_fx
+
+#endif // LE_FX_ENGINE_COMMON_CORE_BYTE_SWAPPER_H_
diff --git a/media/libeffects/loudness/common/core/math.h b/media/libeffects/loudness/common/core/math.h
new file mode 100644
index 0000000..3f302cc
--- /dev/null
+++ b/media/libeffects/loudness/common/core/math.h
@@ -0,0 +1,89 @@
+/*
+ * Copyright (C) 2013 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.
+ */
+
+#ifndef LE_FX_ENGINE_COMMON_CORE_MATH_H_
+#define LE_FX_ENGINE_COMMON_CORE_MATH_H_
+
+#include <math.h>
+#include <algorithm>
+using ::std::min;
+using ::std::max;
+using ::std::fill;
+using ::std::fill_n;using ::std::lower_bound;
+#include <cmath>
+#include <math.h>
+//using ::std::fpclassify;
+
+#include "common/core/os.h"
+#include "common/core/types.h"
+
+namespace le_fx {
+namespace math {
+
+// A fast approximation to log2(.)
+inline float fast_log2(float val) {
+ int* const exp_ptr = reinterpret_cast <int *> (&val);
+ int x = *exp_ptr;
+ const int log_2 = ((x >> 23) & 255) - 128;
+ x &= ~(255 << 23);
+ x += 127 << 23;
+ *exp_ptr = x;
+ val = ((-1.0f / 3) * val + 2) * val - 2.0f / 3;
+ return static_cast<float>(val + log_2);
+}
+
+// A fast approximation to log(.)
+inline float fast_log(float val) {
+ return fast_log2(val) *
+ 0.693147180559945286226763982995180413126945495605468750f;
+}
+
+// An approximation of the exp(.) function using a 5-th order Taylor expansion.
+// It's pretty accurate between +-0.1 and accurate to 10e-3 between +-1
+template <typename T>
+inline T ExpApproximationViaTaylorExpansionOrder5(T x) {
+ const T x2 = x * x;
+ const T x3 = x2 * x;
+ const T x4 = x2 * x2;
+ const T x5 = x3 * x2;
+ return 1.0f + x + 0.5f * x2 +
+ 0.16666666666666665741480812812369549646973609924316406250f * x3 +
+ 0.0416666666666666643537020320309238741174340248107910156250f * x4 +
+ 0.008333333333333333217685101601546193705871701240539550781250f * x5;
+}
+
+} // namespace math
+} // namespace le_fx
+
+// Math functions missing in Android NDK:
+#if defined(LE_FX_OS_ANDROID)
+
+namespace std {
+
+//
+// Round to the nearest integer: We need this implementation
+// since std::round is missing on android.
+//
+template <typename T>
+inline T round(const T &x) {
+ return static_cast<T>(std::floor(static_cast<double>(x) + 0.5));
+}
+
+} // namespace std
+
+#endif // LE_FX_OS_ANDROID
+
+#endif // LE_FX_ENGINE_COMMON_CORE_MATH_H_
diff --git a/media/libeffects/loudness/common/core/os.h b/media/libeffects/loudness/common/core/os.h
new file mode 100644
index 0000000..4a8ce82
--- /dev/null
+++ b/media/libeffects/loudness/common/core/os.h
@@ -0,0 +1,29 @@
+/*
+ * Copyright (C) 2013 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.
+ */
+
+#ifndef LE_FX_ENGINE_COMMON_CORE_OS_H_
+#define LE_FX_ENGINE_COMMON_CORE_OS_H_
+
+// -----------------------------------------------------------------------------
+// OS Identification:
+// -----------------------------------------------------------------------------
+
+#define LE_FX_OS_UNIX
+#if defined(__ANDROID__)
+# define LE_FX_OS_ANDROID
+#endif // Android
+
+#endif // LE_FX_ENGINE_COMMON_CORE_OS_H_
diff --git a/media/libeffects/loudness/common/core/types.h b/media/libeffects/loudness/common/core/types.h
new file mode 100644
index 0000000..d1b6c6a
--- /dev/null
+++ b/media/libeffects/loudness/common/core/types.h
@@ -0,0 +1,31 @@
+/*
+ * Copyright (C) 2013 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.
+ */
+
+#ifndef LE_FX_ENGINE_COMMON_CORE_TYPES_H_
+#define LE_FX_ENGINE_COMMON_CORE_TYPES_H_
+
+#include "common/core/os.h"
+
+#include "common/core/basic_types.h"
+
+#ifndef LE_FX_DISALLOW_COPY_AND_ASSIGN
+#define LE_FX_DISALLOW_COPY_AND_ASSIGN(TypeName) \
+ TypeName(const TypeName&); \
+ void operator=(const TypeName&)
+#endif // LE_FX_DISALLOW_COPY_AND_ASSIGN
+
+
+#endif // LE_FX_ENGINE_COMMON_CORE_TYPES_H_
diff --git a/media/libeffects/loudness/dsp/core/basic-inl.h b/media/libeffects/loudness/dsp/core/basic-inl.h
new file mode 100644
index 0000000..3f77147
--- /dev/null
+++ b/media/libeffects/loudness/dsp/core/basic-inl.h
@@ -0,0 +1,48 @@
+/*
+ * Copyright (C) 2013 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.
+ */
+
+#ifndef LE_FX_ENGINE_DSP_CORE_BASIC_INL_H_
+#define LE_FX_ENGINE_DSP_CORE_BASIC_INL_H_
+
+#include <math.h>
+
+namespace le_fx {
+
+namespace sigmod {
+
+template <typename T>
+int SearchIndex(const T x_data[],
+ T x,
+ int start_index,
+ int end_index) {
+ int start = start_index;
+ int end = end_index;
+ while (end > start + 1) {
+ int i = (end + start) / 2;
+ if (x_data[i] > x) {
+ end = i;
+ } else {
+ start = i;
+ }
+ }
+ return start;
+}
+
+} // namespace sigmod
+
+} // namespace le_fx
+
+#endif // LE_FX_ENGINE_DSP_CORE_BASIC_INL_H_
diff --git a/media/libeffects/loudness/dsp/core/basic.h b/media/libeffects/loudness/dsp/core/basic.h
new file mode 100644
index 0000000..27e0a8d
--- /dev/null
+++ b/media/libeffects/loudness/dsp/core/basic.h
@@ -0,0 +1,48 @@
+/*
+ * Copyright (C) 2013 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.
+ */
+
+#ifndef LE_FX_ENGINE_DSP_CORE_BASIC_H_
+#define LE_FX_ENGINE_DSP_CORE_BASIC_H_
+
+#include <limits.h>
+#include "common/core/math.h"
+#include "common/core/types.h"
+
+namespace le_fx {
+
+namespace sigmod {
+
+// Searchs for the interval that contains <x> using a divide-and-conquer
+// algorithm.
+// X[]: a vector of sorted values (X[i+1] > X[i])
+// x: a value
+// StartIndex: the minimum searched index
+// EndIndex: the maximum searched index
+// returns: the index <i> that satisfies: X[i] <= x <= X[i+1] &&
+// StartIndex <= i <= (EndIndex-1)
+template <typename T>
+int SearchIndex(const T x_data[],
+ T x,
+ int start_index,
+ int end_index);
+
+} // namespace sigmod
+
+} // namespace le_fx
+
+#include "dsp/core/basic-inl.h"
+
+#endif // LE_FX_ENGINE_DSP_CORE_BASIC_H_
diff --git a/media/libeffects/loudness/dsp/core/dynamic_range_compression-inl.h b/media/libeffects/loudness/dsp/core/dynamic_range_compression-inl.h
new file mode 100644
index 0000000..fed8c2a
--- /dev/null
+++ b/media/libeffects/loudness/dsp/core/dynamic_range_compression-inl.h
@@ -0,0 +1,45 @@
+/*
+ * Copyright (C) 2013 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.
+ */
+#ifndef LE_FX_ENGINE_DSP_CORE_DYNAMIC_RANGE_COMPRESSION_INL_H_
+#define LE_FX_ENGINE_DSP_CORE_DYNAMIC_RANGE_COMPRESSION_INL_H_
+
+//#define LOG_NDEBUG 0
+#include <cutils/log.h>
+
+
+namespace le_fx {
+
+
+inline void AdaptiveDynamicRangeCompression::set_knee_threshold(float decibel) {
+ // Converts to 1og-base
+ knee_threshold_in_decibel_ = decibel;
+ knee_threshold_ = 0.1151292546497023061569109358970308676362037658691406250f *
+ decibel + 10.39717719035538401328722102334722876548767089843750f;
+}
+
+
+inline void AdaptiveDynamicRangeCompression::set_knee_threshold_via_target_gain(
+ float target_gain) {
+ const float decibel = target_gain_to_knee_threshold_.Interpolate(
+ target_gain);
+ ALOGE("set_knee_threshold_via_target_gain: decibel =%.3f", decibel);
+ set_knee_threshold(decibel);
+}
+
+} // namespace le_fx
+
+
+#endif // LE_FX_ENGINE_DSP_CORE_DYNAMIC_RANGE_COMPRESSION_INL_H_
diff --git a/media/libeffects/loudness/dsp/core/dynamic_range_compression.cpp b/media/libeffects/loudness/dsp/core/dynamic_range_compression.cpp
new file mode 100644
index 0000000..2bbd043
--- /dev/null
+++ b/media/libeffects/loudness/dsp/core/dynamic_range_compression.cpp
@@ -0,0 +1,106 @@
+/*
+ * Copyright (C) 2013 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.
+ */
+
+#include <cmath>
+
+#include "common/core/math.h"
+#include "common/core/types.h"
+#include "dsp/core/basic.h"
+#include "dsp/core/interpolation.h"
+#include "dsp/core/dynamic_range_compression.h"
+
+//#define LOG_NDEBUG 0
+#include <cutils/log.h>
+
+
+namespace le_fx {
+
+// Definitions for static const class members declared in
+// dynamic_range_compression.h.
+const float AdaptiveDynamicRangeCompression::kMinAbsValue = 0.000001f;
+const float AdaptiveDynamicRangeCompression::kMinLogAbsValue =
+ 0.032766999999999997517097227728299912996590137481689453125f;
+const float AdaptiveDynamicRangeCompression::kFixedPointLimit = 32767.0f;
+const float AdaptiveDynamicRangeCompression::kInverseFixedPointLimit =
+ 1.0f / AdaptiveDynamicRangeCompression::kFixedPointLimit;
+const float AdaptiveDynamicRangeCompression::kDefaultKneeThresholdInDecibel =
+ -8.0f;
+const float AdaptiveDynamicRangeCompression::kCompressionRatio = 7.0f;
+const float AdaptiveDynamicRangeCompression::kTauAttack = 0.001f;
+const float AdaptiveDynamicRangeCompression::kTauRelease = 0.015f;
+
+AdaptiveDynamicRangeCompression::AdaptiveDynamicRangeCompression() {
+ static const float kTargetGain[] = {
+ 1.0f, 2.0f, 3.0f, 4.0f, 5.0f };
+ static const float kKneeThreshold[] = {
+ -8.0f, -8.0f, -8.5f, -9.0f, -10.0f };
+ target_gain_to_knee_threshold_.Initialize(
+ &kTargetGain[0], &kKneeThreshold[0],
+ sizeof(kTargetGain) / sizeof(kTargetGain[0]));
+}
+
+bool AdaptiveDynamicRangeCompression::Initialize(
+ float target_gain, float sampling_rate) {
+ set_knee_threshold_via_target_gain(target_gain);
+ sampling_rate_ = sampling_rate;
+ state_ = 0.0f;
+ compressor_gain_ = 1.0f;
+ if (kTauAttack > 0.0f) {
+ const float taufs = kTauAttack * sampling_rate_;
+ alpha_attack_ = std::exp(-1.0f / taufs);
+ } else {
+ alpha_attack_ = 0.0f;
+ }
+ if (kTauRelease > 0.0f) {
+ const float taufs = kTauRelease * sampling_rate_;
+ alpha_release_ = std::exp(-1.0f / taufs);
+ } else {
+ alpha_release_ = 0.0f;
+ }
+ // Feed-forward topology
+ slope_ = 1.0f / kCompressionRatio - 1.0f;
+ return true;
+}
+
+float AdaptiveDynamicRangeCompression::Compress(float x) {
+ const float max_abs_x = std::max(std::fabs(x), kMinLogAbsValue);
+ const float max_abs_x_dB = math::fast_log(max_abs_x);
+ // Subtract Threshold from log-encoded input to get the amount of overshoot
+ const float overshoot = max_abs_x_dB - knee_threshold_;
+ // Hard half-wave rectifier
+ const float rect = std::max(overshoot, 0.0f);
+ // Multiply rectified overshoot with slope
+ const float cv = rect * slope_;
+ const float prev_state = state_;
+ if (cv <= state_) {
+ state_ = alpha_attack_ * state_ + (1.0f - alpha_attack_) * cv;
+ } else {
+ state_ = alpha_release_ * state_ + (1.0f - alpha_release_) * cv;
+ }
+ compressor_gain_ *=
+ math::ExpApproximationViaTaylorExpansionOrder5(state_ - prev_state);
+ x *= compressor_gain_;
+ if (x > kFixedPointLimit) {
+ return kFixedPointLimit;
+ }
+ if (x < -kFixedPointLimit) {
+ return -kFixedPointLimit;
+ }
+ return x;
+}
+
+} // namespace le_fx
+
diff --git a/media/libeffects/loudness/dsp/core/dynamic_range_compression.h b/media/libeffects/loudness/dsp/core/dynamic_range_compression.h
new file mode 100644
index 0000000..4c015df
--- /dev/null
+++ b/media/libeffects/loudness/dsp/core/dynamic_range_compression.h
@@ -0,0 +1,116 @@
+/*
+ * Copyright (C) 2013 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.
+ */
+#ifndef LE_FX_ENGINE_DSP_CORE_DYNAMIC_RANGE_COMPRESSION_H_
+#define LE_FX_ENGINE_DSP_CORE_DYNAMIC_RANGE_COMPRESSION_H_
+
+#include "common/core/types.h"
+#include "common/core/math.h"
+#include "dsp/core/basic.h"
+#include "dsp/core/interpolation.h"
+
+//#define LOG_NDEBUG 0
+#include <cutils/log.h>
+
+
+namespace le_fx {
+
+// An adaptive dynamic range compression algorithm. The gain adaptation is made
+// at the logarithmic domain and it is based on a Branching-Smooth compensated
+// digital peak detector with different time constants for attack and release.
+class AdaptiveDynamicRangeCompression {
+ public:
+ AdaptiveDynamicRangeCompression();
+
+ // Initializes the compressor using prior information. It assumes that the
+ // input signal is speech from high-quality recordings that is scaled and then
+ // fed to the compressor. The compressor is tuned according to the target gain
+ // that is expected to be applied.
+ //
+ // Target gain receives values between 0.0 and 10.0. The knee threshold is
+ // reduced as the target gain increases in order to fit the increased range of
+ // values.
+ //
+ // Values between 1.0 and 2.0 will only mildly affect your signal. Higher
+ // values will reduce the dynamic range of the signal to the benefit of
+ // increased loudness.
+ //
+ // If nothing is known regarding the input, a `target_gain` of 1.0f is a
+ // relatively safe choice for many signals.
+ bool Initialize(float target_gain, float sampling_rate);
+
+ // A fast version of the algorithm that uses approximate computations for the
+ // log(.) and exp(.).
+ float Compress(float x);
+
+ // This version is slower than Compress(.) but faster than CompressSlow(.)
+ float CompressNormalSpeed(float x);
+
+ // A slow version of the algorithm that is easier for further developement,
+ // tuning and debugging
+ float CompressSlow(float x);
+
+ // Sets knee threshold (in decibel).
+ void set_knee_threshold(float decibel);
+
+ // Sets knee threshold via the target gain using an experimentally derived
+ // relationship.
+ void set_knee_threshold_via_target_gain(float target_gain);
+
+ private:
+ // The minimum accepted absolute input value and it's natural logarithm. This
+ // is to prevent numerical issues when the input is close to zero
+ static const float kMinAbsValue;
+ static const float kMinLogAbsValue;
+ // Fixed-point arithmetic limits
+ static const float kFixedPointLimit;
+ static const float kInverseFixedPointLimit;
+ // The default knee threshold in decibel. The knee threshold defines when the
+ // compressor is actually starting to compress the value of the input samples
+ static const float kDefaultKneeThresholdInDecibel;
+ // The compression ratio is the reciprocal of the slope of the line segment
+ // above the threshold (in the log-domain). The ratio controls the
+ // effectiveness of the compression.
+ static const float kCompressionRatio;
+ // The attack time of the envelope detector
+ static const float kTauAttack;
+ // The release time of the envelope detector
+ static const float kTauRelease;
+
+ float sampling_rate_;
+ // the internal state of the envelope detector
+ float state_;
+ // the latest gain factor that was applied to the input signal
+ float compressor_gain_;
+ // attack constant for exponential dumping
+ float alpha_attack_;
+ // release constant for exponential dumping
+ float alpha_release_;
+ float slope_;
+ // The knee threshold
+ float knee_threshold_;
+ float knee_threshold_in_decibel_;
+ // This interpolator provides the function that relates target gain to knee
+ // threshold.
+ sigmod::InterpolatorLinear<float> target_gain_to_knee_threshold_;
+
+ LE_FX_DISALLOW_COPY_AND_ASSIGN(AdaptiveDynamicRangeCompression);
+};
+
+} // namespace le_fx
+
+#include "dsp/core/dynamic_range_compression-inl.h"
+
+#endif // LE_FX_ENGINE_DSP_CORE_DYNAMIC_RANGE_COMPRESSION_H_
diff --git a/media/libeffects/loudness/dsp/core/interpolation.h b/media/libeffects/loudness/dsp/core/interpolation.h
new file mode 100644
index 0000000..23c287c
--- /dev/null
+++ b/media/libeffects/loudness/dsp/core/interpolation.h
@@ -0,0 +1,24 @@
+/*
+ * Copyright (C) 2013 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.
+ */
+#ifndef LE_FX_ENGINE_DSP_CORE_INTERPOLATION_H_
+#define LE_FX_ENGINE_DSP_CORE_INTERPOLATION_H_
+
+#include "common/core/math.h"
+#include "dsp/core/interpolator_base.h"
+#include "dsp/core/interpolator_linear.h"
+
+#endif // LE_FX_ENGINE_DSP_CORE_INTERPOLATION_H_
+
diff --git a/media/libeffects/loudness/dsp/core/interpolator_base-inl.h b/media/libeffects/loudness/dsp/core/interpolator_base-inl.h
new file mode 100644
index 0000000..bd08b65
--- /dev/null
+++ b/media/libeffects/loudness/dsp/core/interpolator_base-inl.h
@@ -0,0 +1,180 @@
+/*
+ * Copyright (C) 2013 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.
+ */
+
+#ifndef LE_FX_ENGINE_DSP_CORE_INTERPOLATOR_BASE_INL_H_
+#define LE_FX_ENGINE_DSP_CORE_INTERPOLATOR_BASE_INL_H_
+
+#include "dsp/core/basic.h"
+
+//#define LOG_NDEBUG 0
+#include <cutils/log.h>
+
+
+namespace le_fx {
+
+namespace sigmod {
+
+template <typename T, class Algorithm>
+InterpolatorBase<T, Algorithm>::InterpolatorBase() {
+ status_ = false;
+ cached_index_ = 0;
+ x_data_ = NULL;
+ y_data_ = NULL;
+ data_length_ = 0;
+ own_x_data_ = false;
+ x_start_offset_ = 0.0;
+ last_element_index_ = -1;
+ x_inverse_sampling_interval_ = 0.0;
+ state_ = NULL;
+}
+
+template <typename T, class Algorithm>
+InterpolatorBase<T, Algorithm>::~InterpolatorBase() {
+ delete [] state_;
+ if (own_x_data_) {
+ delete [] x_data_;
+ }
+}
+
+template <typename T, class Algorithm>
+bool InterpolatorBase<T, Algorithm>::Initialize(const vector<T> &x_data,
+ const vector<T> &y_data) {
+#ifndef NDEBUG
+ if (x_data.size() != y_data.size()) {
+ LoggerError("InterpolatorBase::Initialize: xData size (%d) != yData size"
+ " (%d)", x_data.size(), y_data.size());
+ }
+#endif
+ return Initialize(&x_data[0], &y_data[0], x_data.size());
+}
+
+template <typename T, class Algorithm>
+bool InterpolatorBase<T, Algorithm>::Initialize(double x_start_offset,
+ double x_sampling_interval,
+ const vector<T> &y_data) {
+ return Initialize(x_start_offset,
+ x_sampling_interval,
+ &y_data[0],
+ y_data.size());
+}
+
+template <typename T, class Algorithm>
+bool InterpolatorBase<T, Algorithm>::Initialize(double x_start_offset,
+ double x_sampling_interval,
+ const T *y_data,
+ int data_length) {
+ // Constructs and populate x-axis data: `x_data_`
+ T *x_data_tmp = new T[data_length];
+ float time_offset = x_start_offset;
+ for (int n = 0; n < data_length; n++) {
+ x_data_tmp[n] = time_offset;
+ time_offset += x_sampling_interval;
+ }
+ Initialize(x_data_tmp, y_data, data_length);
+ // Sets-up the regularly sampled interpolation mode
+ x_start_offset_ = x_start_offset;
+ x_inverse_sampling_interval_ = 1.0 / x_sampling_interval;
+ own_x_data_ = true;
+ return status_;
+}
+
+
+template <typename T, class Algorithm>
+bool InterpolatorBase<T, Algorithm>::Initialize(
+ const T *x_data, const T *y_data, int data_length) {
+ // Default settings
+ cached_index_ = 0;
+ data_length_ = 0;
+ x_start_offset_ = 0;
+ x_inverse_sampling_interval_ = 0;
+ state_ = NULL;
+ // Input data is externally owned
+ own_x_data_ = false;
+ x_data_ = x_data;
+ y_data_ = y_data;
+ data_length_ = data_length;
+ last_element_index_ = data_length - 1;
+ // Check input data sanity
+ for (int n = 0; n < last_element_index_; ++n) {
+ if (x_data_[n + 1] <= x_data_[n]) {
+ ALOGE("InterpolatorBase::Initialize: xData are not ordered or "
+ "contain equal values (X[%d] <= X[%d]) (%.5e <= %.5e)",
+ n + 1, n, x_data_[n + 1], x_data_[n]);
+ status_ = false;
+ return false;
+ }
+ }
+ // Pre-compute internal state by calling the corresponding function of the
+ // derived class.
+ status_ = static_cast<Algorithm*>(this)->SetInternalState();
+ return status_;
+}
+
+template <typename T, class Algorithm>
+T InterpolatorBase<T, Algorithm>::Interpolate(T x) {
+#ifndef NDEBUG
+ if (cached_index_ < 0 || cached_index_ > data_length_ - 2) {
+ LoggerError("InterpolatorBase:Interpolate: CachedIndex_ out of bounds "
+ "[0, %d, %d]", cached_index_, data_length_ - 2);
+ }
+#endif
+ // Search for the containing interval
+ if (x <= x_data_[cached_index_]) {
+ if (cached_index_ <= 0) {
+ cached_index_ = 0;
+ return y_data_[0];
+ }
+ if (x >= x_data_[cached_index_ - 1]) {
+ cached_index_--; // Fast descending
+ } else {
+ if (x <= x_data_[0]) {
+ cached_index_ = 0;
+ return y_data_[0];
+ }
+ cached_index_ = SearchIndex(x_data_, x, 0, cached_index_);
+ }
+ } else {
+ if (cached_index_ >= last_element_index_) {
+ cached_index_ = last_element_index_;
+ return y_data_[last_element_index_];
+ }
+ if (x > x_data_[cached_index_ + 1]) {
+ if (cached_index_ + 2 > last_element_index_) {
+ cached_index_ = last_element_index_ - 1;
+ return y_data_[last_element_index_];
+ }
+ if (x <= x_data_[cached_index_ + 2]) {
+ cached_index_++; // Fast ascending
+ } else {
+ if (x >= x_data_[last_element_index_]) {
+ cached_index_ = last_element_index_ - 1;
+ return y_data_[last_element_index_];
+ }
+ cached_index_ = SearchIndex(
+ x_data_, x, cached_index_, last_element_index_);
+ }
+ }
+ }
+ // Compute interpolated value by calling the corresponding function of the
+ // derived class.
+ return static_cast<Algorithm*>(this)->MethodSpecificInterpolation(x);
+}
+
+} // namespace sigmod
+
+} // namespace le_fx
+
+#endif // LE_FX_ENGINE_DSP_CORE_INTERPOLATOR_BASE_INL_H_
diff --git a/media/libeffects/loudness/dsp/core/interpolator_base.h b/media/libeffects/loudness/dsp/core/interpolator_base.h
new file mode 100644
index 0000000..0cd1a35
--- /dev/null
+++ b/media/libeffects/loudness/dsp/core/interpolator_base.h
@@ -0,0 +1,112 @@
+/*
+ * Copyright (C) 2013 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.
+ */
+
+#ifndef LE_FX_ENGINE_DSP_CORE_INTERPOLATOR_BASE_H_
+#define LE_FX_ENGINE_DSP_CORE_INTERPOLATOR_BASE_H_
+
+#include "common/core/types.h"
+
+namespace le_fx {
+
+namespace sigmod {
+
+// Interpolation base-class that provides the interface, while it is the derived
+// class that provides the specific interpolation algorithm. The following list
+// of interpolation algorithms are currently present:
+//
+// InterpolationSine<T>: weighted interpolation between y_data[n] and
+// y_data[n+1] using a sin(.) weighting factor from
+// 0 to pi/4.
+// InterpolationLinear<T>: linear interpolation
+// InterpolationSplines<T>: spline-based interpolation
+//
+// Example (using derived spline-based interpolation class):
+// InterpolatorSplines<float> interp(x_data, y_data, data_length);
+// for (int n = 0; n < data_length; n++) Y[n] = interp.Interpolate(X[n]);
+//
+template <typename T, class Algorithm>
+class InterpolatorBase {
+ public:
+ InterpolatorBase();
+ ~InterpolatorBase();
+
+ // Generic random-access interpolation with arbitrary spaced x-axis samples.
+ // Below X[0], the interpolator returns Y[0]. Above X[data_length-1], it
+ // returns Y[data_length-1].
+ T Interpolate(T x);
+
+ bool get_status() const {
+ return status_;
+ }
+
+ // Initializes internal buffers.
+ // x_data: [(data_length)x1] x-axis coordinates (searching axis)
+ // y_data: [(data_length)x1] y-axis coordinates (interpolation axis)
+ // data_length: number of points
+ // returns `true` if everything is ok, `false`, otherwise
+ bool Initialize(const T *x_data, const T *y_data, int data_length);
+
+ // Initializes internal buffers.
+ // x_data: x-axis coordinates (searching axis)
+ // y_data: y-axis coordinates (interpolating axis)
+ // returns `true` if everything is ok, `false`, otherwise
+ bool Initialize(const vector<T> &x_data, const vector<T> &y_data);
+
+ // Initialization for regularly sampled sequences, where:
+ // x_data[i] = x_start_offset + i * x_sampling_interval
+ bool Initialize(double x_start_offset,
+ double x_sampling_interval,
+ const vector<T> &y_data);
+
+ // Initialization for regularly sampled sequences, where:
+ // x_data[i] = x_start_offset + i * x_sampling_interval
+ bool Initialize(double x_start_offset,
+ double x_sampling_interval,
+ const T *y_data,
+ int data_length);
+
+ protected:
+ // Is set to false if something goes wrong, and to true if everything is ok.
+ bool status_;
+
+ // The start-index of the previously searched interval
+ int cached_index_;
+
+ // Data points
+ const T *x_data_; // Externally or internally owned, depending on own_x_data_
+ const T *y_data_; // Externally owned (always)
+ int data_length_;
+ // Index of the last element `data_length_ - 1` kept here for optimization
+ int last_element_index_;
+ bool own_x_data_;
+ // For regularly-samples sequences, keep only the boundaries and the intervals
+ T x_start_offset_;
+ float x_inverse_sampling_interval_;
+
+ // Algorithm state (internally owned)
+ double *state_;
+
+ private:
+ LE_FX_DISALLOW_COPY_AND_ASSIGN(InterpolatorBase);
+};
+
+} // namespace sigmod
+
+} // namespace le_fx
+
+#include "dsp/core/interpolator_base-inl.h"
+
+#endif // LE_FX_ENGINE_DSP_CORE_INTERPOLATOR_BASE_H_
diff --git a/media/libeffects/loudness/dsp/core/interpolator_linear.h b/media/libeffects/loudness/dsp/core/interpolator_linear.h
new file mode 100644
index 0000000..434698a
--- /dev/null
+++ b/media/libeffects/loudness/dsp/core/interpolator_linear.h
@@ -0,0 +1,81 @@
+/*
+ * Copyright (C) 2013 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.
+ */
+
+#ifndef LE_FX_ENGINE_DSP_CORE_INTERPOLATOR_LINEAR_H_
+#define LE_FX_ENGINE_DSP_CORE_INTERPOLATOR_LINEAR_H_
+
+#include <math.h>
+#include "dsp/core/interpolator_base.h"
+
+namespace le_fx {
+
+namespace sigmod {
+
+// Linear interpolation class.
+//
+// The main functionality of this class is provided by it's base-class, so
+// please refer to: InterpolatorBase
+//
+// Example:
+// InterpolatorLinear<float> interp(x_data, y_data, data_length);
+// for (int n = 0; n < data_length; n++) Y[n] = interp.Interpolate(X[n]);
+//
+template <typename T>
+class InterpolatorLinear: public InterpolatorBase<T, InterpolatorLinear<T> > {
+ public:
+ InterpolatorLinear() { }
+ ~InterpolatorLinear() { }
+
+ protected:
+ // Provides the main implementation of the linear interpolation algorithm.
+ // Assumes that: X[cached_index_] < x < X[cached_index_ + 1]
+ T MethodSpecificInterpolation(T x);
+
+ // Pre-compute internal state_ parameters.
+ bool SetInternalState();
+
+ private:
+ friend class InterpolatorBase<T, InterpolatorLinear<T> >;
+ typedef InterpolatorBase<T, InterpolatorLinear<T> > BaseClass;
+ using BaseClass::status_;
+ using BaseClass::cached_index_;
+ using BaseClass::x_data_;
+ using BaseClass::y_data_;
+ using BaseClass::data_length_;
+ using BaseClass::state_;
+
+ LE_FX_DISALLOW_COPY_AND_ASSIGN(InterpolatorLinear<T>);
+};
+
+template <typename T>
+inline T InterpolatorLinear<T>::MethodSpecificInterpolation(T x) {
+ T dX = x_data_[cached_index_ + 1] - x_data_[cached_index_];
+ T dY = y_data_[cached_index_ + 1] - y_data_[cached_index_];
+ T dx = x - x_data_[cached_index_];
+ return y_data_[cached_index_] + (dY * dx) / dX;
+}
+
+template <typename T>
+bool InterpolatorLinear<T>::SetInternalState() {
+ state_ = NULL;
+ return true;
+}
+
+} // namespace sigmod
+
+} // namespace le_fx
+
+#endif // LE_FX_ENGINE_DSP_CORE_INTERPOLATOR_LINEAR_H_