diff --git a/media/audioaidlconversion/AidlConversionCppNdk.cpp b/media/audioaidlconversion/AidlConversionCppNdk.cpp
index 46bb6f1..8c2b940 100644
--- a/media/audioaidlconversion/AidlConversionCppNdk.cpp
+++ b/media/audioaidlconversion/AidlConversionCppNdk.cpp
@@ -43,6 +43,9 @@
 
 using ::android::BAD_VALUE;
 using ::android::OK;
+using ::android::String16;
+using ::android::String8;
+using ::android::status_t;
 using ::android::base::unexpected;
 
 using media::audio::common::AudioChannelLayout;
diff --git a/media/audioaidlconversion/AidlConversionEffect.cpp b/media/audioaidlconversion/AidlConversionEffect.cpp
index c053a5d..611cfab 100644
--- a/media/audioaidlconversion/AidlConversionEffect.cpp
+++ b/media/audioaidlconversion/AidlConversionEffect.cpp
@@ -49,6 +49,7 @@
 
 using ::android::BAD_VALUE;
 using ::android::OK;
+using ::android::status_t;
 using ::android::base::unexpected;
 using ::android::effect::utils::EffectParamReader;
 using ::android::effect::utils::EffectParamWriter;
diff --git a/media/audioaidlconversion/include/media/AidlConversionCppNdk-impl.h b/media/audioaidlconversion/include/media/AidlConversionCppNdk-impl.h
new file mode 100644
index 0000000..9100892
--- /dev/null
+++ b/media/audioaidlconversion/include/media/AidlConversionCppNdk-impl.h
@@ -0,0 +1,433 @@
+/*
+ * Copyright (C) 2023 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.
+ */
+
+// WARNING: This file is intended for multiple inclusion.
+// Do not include directly, use 'AidlConversionCppNdk.h'.
+#if (defined(BACKEND_NDK_IMPL) && !defined(AUDIO_AIDL_CONVERSION_AIDL_CONVERSION_CPP_NDK_NDK)) || \
+    (!defined(BACKEND_NDK_IMPL) && !defined(AUDIO_AIDL_CONVERSION_AIDL_CONVERSION_CPP_NDK_CPP))
+#if defined(BACKEND_NDK_IMPL)
+#define AUDIO_AIDL_CONVERSION_AIDL_CONVERSION_CPP_NDK_NDK
+#else
+#define AUDIO_AIDL_CONVERSION_AIDL_CONVERSION_CPP_NDK_CPP
+#endif  // BACKEND_NDK_IMPL
+
+#include <limits>
+#include <type_traits>
+
+/**
+ * Can handle conversion between AIDL (both CPP and NDK backend) and legacy type.
+ * Controlled by the cflags preprocessor in Android.bp.
+ */
+#if defined(BACKEND_NDK_IMPL)
+#define PREFIX(f) <aidl/f>
+#else
+#define PREFIX(f) <f>
+#endif
+
+#include PREFIX(android/media/audio/common/AudioChannelLayout.h)
+#include PREFIX(android/media/audio/common/AudioConfig.h)
+#include PREFIX(android/media/audio/common/AudioConfigBase.h)
+#include PREFIX(android/media/audio/common/AudioContentType.h)
+#include PREFIX(android/media/audio/common/AudioDeviceDescription.h)
+#include PREFIX(android/media/audio/common/AudioDualMonoMode.h)
+#include PREFIX(android/media/audio/common/AudioEncapsulationMetadataType.h)
+#include PREFIX(android/media/audio/common/AudioEncapsulationMode.h)
+#include PREFIX(android/media/audio/common/AudioEncapsulationType.h)
+#include PREFIX(android/media/audio/common/AudioFormatDescription.h)
+#include PREFIX(android/media/audio/common/AudioGain.h)
+#include PREFIX(android/media/audio/common/AudioGainConfig.h)
+#include PREFIX(android/media/audio/common/AudioGainMode.h)
+#include PREFIX(android/media/audio/common/AudioInputFlags.h)
+#include PREFIX(android/media/audio/common/AudioIoFlags.h)
+#include PREFIX(android/media/audio/common/AudioLatencyMode.h)
+#include PREFIX(android/media/audio/common/AudioMode.h)
+#include PREFIX(android/media/audio/common/AudioOffloadInfo.h)
+#include PREFIX(android/media/audio/common/AudioOutputFlags.h)
+#include PREFIX(android/media/audio/common/AudioPort.h)
+#include PREFIX(android/media/audio/common/AudioPortConfig.h)
+#include PREFIX(android/media/audio/common/AudioPortExt.h)
+#include PREFIX(android/media/audio/common/AudioPortMixExt.h)
+#include PREFIX(android/media/audio/common/AudioPlaybackRate.h)
+#include PREFIX(android/media/audio/common/AudioProfile.h)
+#include PREFIX(android/media/audio/common/AudioSource.h)
+#include PREFIX(android/media/audio/common/AudioStandard.h)
+#include PREFIX(android/media/audio/common/AudioUsage.h)
+#include PREFIX(android/media/audio/common/AudioUuid.h)
+#include PREFIX(android/media/audio/common/ExtraAudioDescriptor.h)
+#include PREFIX(android/media/audio/common/Int.h)
+#include PREFIX(android/media/audio/common/MicrophoneDynamicInfo.h)
+#include PREFIX(android/media/audio/common/MicrophoneInfo.h)
+#undef PREFIX
+
+#include <system/audio.h>
+#include <system/audio_effect.h>
+
+#if defined(BACKEND_NDK_IMPL)
+namespace aidl {
+#endif
+
+namespace android {
+
+// maxSize is the size of the C-string buffer (including the 0-terminator), NOT the max length of
+// the string.
+::android::status_t aidl2legacy_string(std::string_view aidl, char* dest, size_t maxSize);
+ConversionResult<std::string> legacy2aidl_string(const char* legacy, size_t maxSize);
+
+ConversionResult<audio_module_handle_t> aidl2legacy_int32_t_audio_module_handle_t(int32_t aidl);
+ConversionResult<int32_t> legacy2aidl_audio_module_handle_t_int32_t(audio_module_handle_t legacy);
+
+ConversionResult<audio_io_handle_t> aidl2legacy_int32_t_audio_io_handle_t(int32_t aidl);
+ConversionResult<int32_t> legacy2aidl_audio_io_handle_t_int32_t(audio_io_handle_t legacy);
+
+ConversionResult<audio_port_handle_t> aidl2legacy_int32_t_audio_port_handle_t(int32_t aidl);
+ConversionResult<int32_t> legacy2aidl_audio_port_handle_t_int32_t(audio_port_handle_t legacy);
+
+ConversionResult<audio_patch_handle_t> aidl2legacy_int32_t_audio_patch_handle_t(int32_t aidl);
+ConversionResult<int32_t> legacy2aidl_audio_patch_handle_t_int32_t(audio_patch_handle_t legacy);
+
+ConversionResult<audio_unique_id_t> aidl2legacy_int32_t_audio_unique_id_t(int32_t aidl);
+ConversionResult<int32_t> legacy2aidl_audio_unique_id_t_int32_t(audio_unique_id_t legacy);
+
+ConversionResult<audio_hw_sync_t> aidl2legacy_int32_t_audio_hw_sync_t(int32_t aidl);
+ConversionResult<int32_t> legacy2aidl_audio_hw_sync_t_int32_t(audio_hw_sync_t legacy);
+
+ConversionResult<unsigned int> aidl2legacy_int32_t_config_mask(int32_t aidl);
+ConversionResult<int32_t> legacy2aidl_config_mask_int32_t(unsigned int legacy);
+
+ConversionResult<pid_t> aidl2legacy_int32_t_pid_t(int32_t aidl);
+ConversionResult<int32_t> legacy2aidl_pid_t_int32_t(pid_t legacy);
+
+ConversionResult<uid_t> aidl2legacy_int32_t_uid_t(int32_t aidl);
+ConversionResult<int32_t> legacy2aidl_uid_t_int32_t(uid_t legacy);
+
+ConversionResult<::android::String8> aidl2legacy_string_view_String8(std::string_view aidl);
+ConversionResult<std::string> legacy2aidl_String8_string(const ::android::String8& legacy);
+
+ConversionResult<::android::String16> aidl2legacy_string_view_String16(std::string_view aidl);
+ConversionResult<std::string> legacy2aidl_String16_string(const ::android::String16& legacy);
+
+ConversionResult<std::optional<::android::String16>>
+aidl2legacy_optional_string_view_optional_String16(std::optional<std::string_view> aidl);
+ConversionResult<std::optional<std::string_view>>
+legacy2aidl_optional_String16_optional_string(std::optional<::android::String16> legacy);
+
+ConversionResult<audio_channel_mask_t> aidl2legacy_AudioChannelLayout_audio_channel_mask_t(
+        const media::audio::common::AudioChannelLayout& aidl, bool isInput);
+ConversionResult<media::audio::common::AudioChannelLayout>
+legacy2aidl_audio_channel_mask_t_AudioChannelLayout(audio_channel_mask_t legacy, bool isInput);
+
+audio_channel_mask_t aidl2legacy_AudioChannelLayout_layout_audio_channel_mask_t_bits(
+        int aidlLayout, bool isInput);
+int legacy2aidl_audio_channel_mask_t_bits_AudioChannelLayout_layout(
+        audio_channel_mask_t legacy, bool isInput);
+
+enum class AudioPortDirection {
+    INPUT, OUTPUT
+};
+ConversionResult<AudioPortDirection> portDirection(audio_port_role_t role, audio_port_type_t type);
+ConversionResult<audio_port_role_t> portRole(AudioPortDirection direction, audio_port_type_t type);
+
+ConversionResult<audio_config_t>
+aidl2legacy_AudioConfig_audio_config_t(const media::audio::common::AudioConfig& aidl, bool isInput);
+ConversionResult<media::audio::common::AudioConfig>
+legacy2aidl_audio_config_t_AudioConfig(const audio_config_t& legacy, bool isInput);
+
+ConversionResult<audio_config_base_t>
+aidl2legacy_AudioConfigBase_audio_config_base_t(
+        const media::audio::common::AudioConfigBase& aidl, bool isInput);
+ConversionResult<media::audio::common::AudioConfigBase>
+legacy2aidl_audio_config_base_t_AudioConfigBase(const audio_config_base_t& legacy, bool isInput);
+
+ConversionResult<audio_input_flags_t>
+aidl2legacy_AudioInputFlags_audio_input_flags_t(media::audio::common::AudioInputFlags aidl);
+ConversionResult<media::audio::common::AudioInputFlags>
+legacy2aidl_audio_input_flags_t_AudioInputFlags(audio_input_flags_t legacy);
+
+ConversionResult<audio_output_flags_t>
+aidl2legacy_AudioOutputFlags_audio_output_flags_t(media::audio::common::AudioOutputFlags aidl);
+ConversionResult<media::audio::common::AudioOutputFlags>
+legacy2aidl_audio_output_flags_t_AudioOutputFlags(audio_output_flags_t legacy);
+
+ConversionResult<audio_input_flags_t> aidl2legacy_int32_t_audio_input_flags_t_mask(
+        int32_t aidl);
+ConversionResult<int32_t> legacy2aidl_audio_input_flags_t_int32_t_mask(
+        audio_input_flags_t legacy);
+
+ConversionResult<audio_output_flags_t> aidl2legacy_int32_t_audio_output_flags_t_mask(
+        int32_t aidl);
+ConversionResult<int32_t> legacy2aidl_audio_output_flags_t_int32_t_mask(
+        audio_output_flags_t legacy);
+
+ConversionResult<audio_io_flags> aidl2legacy_AudioIoFlags_audio_io_flags(
+        const media::audio::common::AudioIoFlags& aidl, bool isInput);
+ConversionResult<media::audio::common::AudioIoFlags> legacy2aidl_audio_io_flags_AudioIoFlags(
+        const audio_io_flags& legacy, bool isInput);
+
+ConversionResult<audio_session_t> aidl2legacy_int32_t_audio_session_t(int32_t aidl);
+ConversionResult<int32_t> legacy2aidl_audio_session_t_int32_t(audio_session_t legacy);
+
+ConversionResult<audio_content_type_t>
+aidl2legacy_AudioContentType_audio_content_type_t(
+        media::audio::common::AudioContentType aidl);
+ConversionResult<media::audio::common::AudioContentType>
+legacy2aidl_audio_content_type_t_AudioContentType(audio_content_type_t legacy);
+
+ConversionResult<audio_devices_t> aidl2legacy_AudioDeviceDescription_audio_devices_t(
+        const media::audio::common::AudioDeviceDescription& aidl);
+ConversionResult<media::audio::common::AudioDeviceDescription>
+legacy2aidl_audio_devices_t_AudioDeviceDescription(audio_devices_t legacy);
+
+::android::status_t aidl2legacy_AudioDevice_audio_device(
+        const media::audio::common::AudioDevice& aidl, audio_devices_t* legacyType,
+        char* legacyAddress);
+::android::status_t aidl2legacy_AudioDevice_audio_device(
+        const media::audio::common::AudioDevice& aidl, audio_devices_t* legacyType,
+        ::android::String8* legacyAddress);
+::android::status_t aidl2legacy_AudioDevice_audio_device(
+        const media::audio::common::AudioDevice& aidl, audio_devices_t* legacyType,
+        std::string* legacyAddress);
+
+ConversionResult<media::audio::common::AudioDevice> legacy2aidl_audio_device_AudioDevice(
+        audio_devices_t legacyType, const char* legacyAddress);
+ConversionResult<media::audio::common::AudioDevice> legacy2aidl_audio_device_AudioDevice(
+        audio_devices_t legacyType, const ::android::String8& legacyAddress);
+
+ConversionResult<audio_extra_audio_descriptor>
+aidl2legacy_ExtraAudioDescriptor_audio_extra_audio_descriptor(
+        const media::audio::common::ExtraAudioDescriptor& aidl);
+
+ConversionResult<media::audio::common::ExtraAudioDescriptor>
+legacy2aidl_audio_extra_audio_descriptor_ExtraAudioDescriptor(
+        const audio_extra_audio_descriptor& legacy);
+
+ConversionResult<audio_encapsulation_metadata_type_t>
+aidl2legacy_AudioEncapsulationMetadataType_audio_encapsulation_metadata_type_t(
+        media::audio::common::AudioEncapsulationMetadataType aidl);
+ConversionResult<media::audio::common::AudioEncapsulationMetadataType>
+legacy2aidl_audio_encapsulation_metadata_type_t_AudioEncapsulationMetadataType(
+        audio_encapsulation_metadata_type_t legacy);
+
+ConversionResult<uint32_t> aidl2legacy_AudioEncapsulationMetadataType_mask(int32_t aidl);
+ConversionResult<int32_t> legacy2aidl_AudioEncapsulationMetadataType_mask(uint32_t legacy);
+
+ConversionResult<audio_encapsulation_mode_t>
+aidl2legacy_AudioEncapsulationMode_audio_encapsulation_mode_t(
+        media::audio::common::AudioEncapsulationMode aidl);
+ConversionResult<media::audio::common::AudioEncapsulationMode>
+legacy2aidl_audio_encapsulation_mode_t_AudioEncapsulationMode(audio_encapsulation_mode_t legacy);
+
+ConversionResult<uint32_t> aidl2legacy_AudioEncapsulationMode_mask(int32_t aidl);
+ConversionResult<int32_t> legacy2aidl_AudioEncapsulationMode_mask(uint32_t legacy);
+
+ConversionResult<audio_encapsulation_type_t>
+aidl2legacy_AudioEncapsulationType_audio_encapsulation_type_t(
+        const media::audio::common::AudioEncapsulationType& aidl);
+ConversionResult<media::audio::common::AudioEncapsulationType>
+legacy2aidl_audio_encapsulation_type_t_AudioEncapsulationType(
+        const audio_encapsulation_type_t& legacy);
+
+ConversionResult<audio_format_t> aidl2legacy_AudioFormatDescription_audio_format_t(
+        const media::audio::common::AudioFormatDescription& aidl);
+ConversionResult<media::audio::common::AudioFormatDescription>
+legacy2aidl_audio_format_t_AudioFormatDescription(audio_format_t legacy);
+
+ConversionResult<audio_gain_mode_t>
+aidl2legacy_AudioGainMode_audio_gain_mode_t(media::audio::common::AudioGainMode aidl);
+ConversionResult<media::audio::common::AudioGainMode>
+legacy2aidl_audio_gain_mode_t_AudioGainMode(audio_gain_mode_t legacy);
+
+ConversionResult<audio_gain_mode_t> aidl2legacy_int32_t_audio_gain_mode_t_mask(int32_t aidl);
+ConversionResult<int32_t> legacy2aidl_audio_gain_mode_t_int32_t_mask(audio_gain_mode_t legacy);
+
+ConversionResult<audio_gain_config> aidl2legacy_AudioGainConfig_audio_gain_config(
+        const media::audio::common::AudioGainConfig& aidl, bool isInput);
+ConversionResult<media::audio::common::AudioGainConfig>
+legacy2aidl_audio_gain_config_AudioGainConfig(const audio_gain_config& legacy, bool isInput);
+
+ConversionResult<audio_gain>
+aidl2legacy_AudioGain_audio_gain(const media::audio::common::AudioGain& aidl, bool isInput);
+ConversionResult<media::audio::common::AudioGain>
+legacy2aidl_audio_gain_AudioGain(const audio_gain& legacy, bool isInput);
+
+ConversionResult<audio_input_flags_t>
+aidl2legacy_AudioInputFlags_audio_input_flags_t(media::audio::common::AudioInputFlags aidl);
+ConversionResult<media::audio::common::AudioInputFlags>
+legacy2aidl_audio_input_flags_t_AudioInputFlags(audio_input_flags_t legacy);
+
+ConversionResult<audio_mode_t>
+aidl2legacy_AudioMode_audio_mode_t(media::audio::common::AudioMode aidl);
+ConversionResult<media::audio::common::AudioMode>
+legacy2aidl_audio_mode_t_AudioMode(audio_mode_t legacy);
+
+ConversionResult<audio_offload_info_t>
+aidl2legacy_AudioOffloadInfo_audio_offload_info_t(
+        const media::audio::common::AudioOffloadInfo& aidl);
+ConversionResult<media::audio::common::AudioOffloadInfo>
+legacy2aidl_audio_offload_info_t_AudioOffloadInfo(const audio_offload_info_t& legacy);
+
+ConversionResult<audio_output_flags_t>
+aidl2legacy_AudioOutputFlags_audio_output_flags_t(media::audio::common::AudioOutputFlags aidl);
+ConversionResult<media::audio::common::AudioOutputFlags>
+legacy2aidl_audio_output_flags_t_AudioOutputFlags(audio_output_flags_t legacy);
+
+// This type is unnamed in the original definition, thus we name it here.
+using audio_port_config_mix_ext_usecase = decltype(audio_port_config_mix_ext::usecase);
+ConversionResult<audio_port_config_mix_ext_usecase>
+aidl2legacy_AudioPortMixExtUseCase_audio_port_config_mix_ext_usecase(
+        const media::audio::common::AudioPortMixExtUseCase& aidl, bool isInput);
+ConversionResult<media::audio::common::AudioPortMixExtUseCase>
+legacy2aidl_audio_port_config_mix_ext_usecase_AudioPortMixExtUseCase(
+        const audio_port_config_mix_ext_usecase& legacy, bool isInput);
+
+ConversionResult<audio_port_config_device_ext>
+aidl2legacy_AudioPortDeviceExt_audio_port_config_device_ext(
+        const media::audio::common::AudioPortDeviceExt& aidl);
+ConversionResult<media::audio::common::AudioPortDeviceExt>
+        legacy2aidl_audio_port_config_device_ext_AudioPortDeviceExt(
+        const audio_port_config_device_ext& legacy);
+
+::android::status_t aidl2legacy_AudioPortConfig_audio_port_config(
+        const media::audio::common::AudioPortConfig& aidl, bool isInput,
+        audio_port_config* legacy, int32_t* portId);
+ConversionResult<media::audio::common::AudioPortConfig>
+legacy2aidl_audio_port_config_AudioPortConfig(
+        const audio_port_config& legacy, bool isInput, int32_t portId);
+
+ConversionResult<audio_port_mix_ext> aidl2legacy_AudioPortMixExt_audio_port_mix_ext(
+        const media::audio::common::AudioPortMixExt& aidl);
+ConversionResult<media::audio::common::AudioPortMixExt>
+legacy2aidl_audio_port_mix_ext_AudioPortMixExt(
+        const audio_port_mix_ext& legacy);
+
+ConversionResult<audio_port_device_ext>
+aidl2legacy_AudioPortDeviceExt_audio_port_device_ext(
+        const media::audio::common::AudioPortDeviceExt& aidl);
+ConversionResult<media::audio::common::AudioPortDeviceExt>
+legacy2aidl_audio_port_device_ext_AudioPortDeviceExt(
+        const audio_port_device_ext& legacy);
+
+ConversionResult<audio_port_v7>
+aidl2legacy_AudioPort_audio_port_v7(
+        const media::audio::common::AudioPort& aidl, bool isInput);
+ConversionResult<media::audio::common::AudioPort>
+legacy2aidl_audio_port_v7_AudioPort(const audio_port_v7& legacy, bool isInput);
+
+ConversionResult<audio_profile> aidl2legacy_AudioProfile_audio_profile(
+        const media::audio::common::AudioProfile& aidl, bool isInput);
+ConversionResult<media::audio::common::AudioProfile> legacy2aidl_audio_profile_AudioProfile(
+        const audio_profile& legacy, bool isInput);
+
+ConversionResult<audio_standard_t> aidl2legacy_AudioStandard_audio_standard_t(
+        media::audio::common::AudioStandard aidl);
+ConversionResult<media::audio::common::AudioStandard> legacy2aidl_audio_standard_t_AudioStandard(
+        audio_standard_t legacy);
+
+ConversionResult<audio_source_t> aidl2legacy_AudioSource_audio_source_t(
+        media::audio::common::AudioSource aidl);
+ConversionResult<media::audio::common::AudioSource> legacy2aidl_audio_source_t_AudioSource(
+        audio_source_t legacy);
+
+ConversionResult<audio_usage_t> aidl2legacy_AudioUsage_audio_usage_t(
+        media::audio::common::AudioUsage aidl);
+ConversionResult<media::audio::common::AudioUsage> legacy2aidl_audio_usage_t_AudioUsage(
+        audio_usage_t legacy);
+
+ConversionResult<audio_uuid_t> aidl2legacy_AudioUuid_audio_uuid_t(
+        const media::audio::common::AudioUuid &aidl);
+ConversionResult<media::audio::common::AudioUuid> legacy2aidl_audio_uuid_t_AudioUuid(
+        const audio_uuid_t& legacy);
+
+ConversionResult<audio_dual_mono_mode_t>
+aidl2legacy_AudioDualMonoMode_audio_dual_mono_mode_t(media::audio::common::AudioDualMonoMode aidl);
+ConversionResult<media::audio::common::AudioDualMonoMode>
+legacy2aidl_audio_dual_mono_mode_t_AudioDualMonoMode(audio_dual_mono_mode_t legacy);
+
+ConversionResult<audio_timestretch_fallback_mode_t>
+aidl2legacy_TimestretchFallbackMode_audio_timestretch_fallback_mode_t(
+        media::audio::common::AudioPlaybackRate::TimestretchFallbackMode aidl);
+ConversionResult<media::audio::common::AudioPlaybackRate::TimestretchFallbackMode>
+legacy2aidl_audio_timestretch_fallback_mode_t_TimestretchFallbackMode(
+        audio_timestretch_fallback_mode_t legacy);
+
+ConversionResult<audio_timestretch_stretch_mode_t>
+aidl2legacy_TimestretchMode_audio_timestretch_stretch_mode_t(
+        media::audio::common::AudioPlaybackRate::TimestretchMode aidl);
+ConversionResult<media::audio::common::AudioPlaybackRate::TimestretchMode>
+legacy2aidl_audio_timestretch_stretch_mode_t_TimestretchMode(
+        audio_timestretch_stretch_mode_t legacy);
+
+ConversionResult<audio_playback_rate_t>
+aidl2legacy_AudioPlaybackRate_audio_playback_rate_t(
+        const media::audio::common::AudioPlaybackRate& aidl);
+ConversionResult<media::audio::common::AudioPlaybackRate>
+legacy2aidl_audio_playback_rate_t_AudioPlaybackRate(const audio_playback_rate_t& legacy);
+
+ConversionResult<audio_latency_mode_t>
+aidl2legacy_AudioLatencyMode_audio_latency_mode_t(media::audio::common::AudioLatencyMode aidl);
+ConversionResult<media::audio::common::AudioLatencyMode>
+legacy2aidl_audio_latency_mode_t_AudioLatencyMode(audio_latency_mode_t legacy);
+
+ConversionResult<audio_microphone_location_t>
+aidl2legacy_MicrophoneInfoLocation_audio_microphone_location_t(
+        media::audio::common::MicrophoneInfo::Location aidl);
+ConversionResult<media::audio::common::MicrophoneInfo::Location>
+legacy2aidl_audio_microphone_location_t_MicrophoneInfoLocation(audio_microphone_location_t legacy);
+
+ConversionResult<audio_microphone_group_t> aidl2legacy_int32_t_audio_microphone_group_t(
+        int32_t aidl);
+ConversionResult<int32_t> legacy2aidl_audio_microphone_group_t_int32_t(
+        audio_microphone_group_t legacy);
+
+ConversionResult<audio_microphone_directionality_t>
+aidl2legacy_MicrophoneInfoDirectionality_audio_microphone_directionality_t(
+        media::audio::common::MicrophoneInfo::Directionality aidl);
+ConversionResult<media::audio::common::MicrophoneInfo::Directionality>
+legacy2aidl_audio_microphone_directionality_t_MicrophoneInfoDirectionality(
+        audio_microphone_directionality_t legacy);
+
+ConversionResult<audio_microphone_coordinate>
+aidl2legacy_MicrophoneInfoCoordinate_audio_microphone_coordinate(
+        const media::audio::common::MicrophoneInfo::Coordinate& aidl);
+ConversionResult<media::audio::common::MicrophoneInfo::Coordinate>
+legacy2aidl_audio_microphone_coordinate_MicrophoneInfoCoordinate(
+        const audio_microphone_coordinate& legacy);
+
+ConversionResult<audio_microphone_channel_mapping_t>
+aidl2legacy_MicrophoneDynamicInfoChannelMapping_audio_microphone_channel_mapping_t(
+        media::audio::common::MicrophoneDynamicInfo::ChannelMapping aidl);
+ConversionResult<media::audio::common::MicrophoneDynamicInfo::ChannelMapping>
+legacy2aidl_audio_microphone_channel_mapping_t_MicrophoneDynamicInfoChannelMapping(
+        audio_microphone_channel_mapping_t legacy);
+
+ConversionResult<audio_microphone_characteristic_t>
+aidl2legacy_MicrophoneInfos_audio_microphone_characteristic_t(
+        const media::audio::common::MicrophoneInfo& aidlInfo,
+        const media::audio::common::MicrophoneDynamicInfo& aidlDynamic);
+::android::status_t
+legacy2aidl_audio_microphone_characteristic_t_MicrophoneInfos(
+        const audio_microphone_characteristic_t& legacy,
+        media::audio::common::MicrophoneInfo* aidlInfo,
+        media::audio::common::MicrophoneDynamicInfo* aidlDynamic);
+
+}  // namespace android
+
+#if defined(BACKEND_NDK_IMPL)
+} // aidl
+#endif
+
+// (defined(BACKEND_NDK_IMPL) && !defined(AUDIO_AIDL_CONVERSION_AIDL_CONVERSION_CPP_NDK_NDK)) || \
+// (!defined(BACKEND_NDK_IMPL) && !defined(AUDIO_AIDL_CONVERSION_AIDL_CONVERSION_CPP_NDK_CPP))
+#endif
diff --git a/media/audioaidlconversion/include/media/AidlConversionCppNdk.h b/media/audioaidlconversion/include/media/AidlConversionCppNdk.h
index e1daf31..ea168a4 100644
--- a/media/audioaidlconversion/include/media/AidlConversionCppNdk.h
+++ b/media/audioaidlconversion/include/media/AidlConversionCppNdk.h
@@ -16,412 +16,19 @@
 
 #pragma once
 
-#include <limits>
-#include <type_traits>
-#include <system/audio.h>
-
-/**
- * Can handle conversion between AIDL (both CPP and NDK backend) and legacy type.
- * Controlled by the cflags preprocessor in Android.bp.
- */
-#if defined(BACKEND_NDK)
-#define PREFIX(f) <aidl/f>
-#else
-#define PREFIX(f) <f>
-#endif
-
-#include PREFIX(android/media/audio/common/AudioChannelLayout.h)
-#include PREFIX(android/media/audio/common/AudioConfig.h)
-#include PREFIX(android/media/audio/common/AudioConfigBase.h)
-#include PREFIX(android/media/audio/common/AudioContentType.h)
-#include PREFIX(android/media/audio/common/AudioDeviceDescription.h)
-#include PREFIX(android/media/audio/common/AudioDualMonoMode.h)
-#include PREFIX(android/media/audio/common/AudioEncapsulationMetadataType.h)
-#include PREFIX(android/media/audio/common/AudioEncapsulationMode.h)
-#include PREFIX(android/media/audio/common/AudioEncapsulationType.h)
-#include PREFIX(android/media/audio/common/AudioFormatDescription.h)
-#include PREFIX(android/media/audio/common/AudioGain.h)
-#include PREFIX(android/media/audio/common/AudioGainConfig.h)
-#include PREFIX(android/media/audio/common/AudioGainMode.h)
-#include PREFIX(android/media/audio/common/AudioInputFlags.h)
-#include PREFIX(android/media/audio/common/AudioIoFlags.h)
-#include PREFIX(android/media/audio/common/AudioLatencyMode.h)
-#include PREFIX(android/media/audio/common/AudioMode.h)
-#include PREFIX(android/media/audio/common/AudioOffloadInfo.h)
-#include PREFIX(android/media/audio/common/AudioOutputFlags.h)
-#include PREFIX(android/media/audio/common/AudioPort.h)
-#include PREFIX(android/media/audio/common/AudioPortConfig.h)
-#include PREFIX(android/media/audio/common/AudioPortExt.h)
-#include PREFIX(android/media/audio/common/AudioPortMixExt.h)
-#include PREFIX(android/media/audio/common/AudioPlaybackRate.h)
-#include PREFIX(android/media/audio/common/AudioProfile.h)
-#include PREFIX(android/media/audio/common/AudioSource.h)
-#include PREFIX(android/media/audio/common/AudioStandard.h)
-#include PREFIX(android/media/audio/common/AudioUsage.h)
-#include PREFIX(android/media/audio/common/AudioUuid.h)
-#include PREFIX(android/media/audio/common/ExtraAudioDescriptor.h)
-#include PREFIX(android/media/audio/common/Int.h)
-#include PREFIX(android/media/audio/common/MicrophoneDynamicInfo.h)
-#include PREFIX(android/media/audio/common/MicrophoneInfo.h)
-#undef PREFIX
-
+// Since conversion functions use ConversionResult, pull it in here.
 #include <media/AidlConversionUtil.h>
-#include <system/audio.h>
-#include <system/audio_effect.h>
 
-using ::android::String16;
-using ::android::String8;
-using ::android::status_t;
+// Include 'AidlConversionCppNdk.h' once if 'BACKEND_NDK' is defined,
+// or no 'BACKEND_*' is defined (C++ backend). Include twice if
+// 'BACKEND_CPP_NDK' is defined: once with 'BACKEND_NDK_IMPL', once w/o defines.
 
-#if defined(BACKEND_NDK)
-namespace aidl {
+#if defined(BACKEND_CPP_NDK) || defined(BACKEND_NDK)
+#define BACKEND_NDK_IMPL
+#include <media/AidlConversionCppNdk-impl.h>
+#undef BACKEND_NDK_IMPL
 #endif
 
-namespace android {
-
-// maxSize is the size of the C-string buffer (including the 0-terminator), NOT the max length of
-// the string.
-status_t aidl2legacy_string(std::string_view aidl, char* dest, size_t maxSize);
-ConversionResult<std::string> legacy2aidl_string(const char* legacy, size_t maxSize);
-
-ConversionResult<audio_module_handle_t> aidl2legacy_int32_t_audio_module_handle_t(int32_t aidl);
-ConversionResult<int32_t> legacy2aidl_audio_module_handle_t_int32_t(audio_module_handle_t legacy);
-
-ConversionResult<audio_io_handle_t> aidl2legacy_int32_t_audio_io_handle_t(int32_t aidl);
-ConversionResult<int32_t> legacy2aidl_audio_io_handle_t_int32_t(audio_io_handle_t legacy);
-
-ConversionResult<audio_port_handle_t> aidl2legacy_int32_t_audio_port_handle_t(int32_t aidl);
-ConversionResult<int32_t> legacy2aidl_audio_port_handle_t_int32_t(audio_port_handle_t legacy);
-
-ConversionResult<audio_patch_handle_t> aidl2legacy_int32_t_audio_patch_handle_t(int32_t aidl);
-ConversionResult<int32_t> legacy2aidl_audio_patch_handle_t_int32_t(audio_patch_handle_t legacy);
-
-ConversionResult<audio_unique_id_t> aidl2legacy_int32_t_audio_unique_id_t(int32_t aidl);
-ConversionResult<int32_t> legacy2aidl_audio_unique_id_t_int32_t(audio_unique_id_t legacy);
-
-ConversionResult<audio_hw_sync_t> aidl2legacy_int32_t_audio_hw_sync_t(int32_t aidl);
-ConversionResult<int32_t> legacy2aidl_audio_hw_sync_t_int32_t(audio_hw_sync_t legacy);
-
-ConversionResult<unsigned int> aidl2legacy_int32_t_config_mask(int32_t aidl);
-ConversionResult<int32_t> legacy2aidl_config_mask_int32_t(unsigned int legacy);
-
-ConversionResult<pid_t> aidl2legacy_int32_t_pid_t(int32_t aidl);
-ConversionResult<int32_t> legacy2aidl_pid_t_int32_t(pid_t legacy);
-
-ConversionResult<uid_t> aidl2legacy_int32_t_uid_t(int32_t aidl);
-ConversionResult<int32_t> legacy2aidl_uid_t_int32_t(uid_t legacy);
-
-ConversionResult<String8> aidl2legacy_string_view_String8(std::string_view aidl);
-ConversionResult<std::string> legacy2aidl_String8_string(const String8& legacy);
-
-ConversionResult<String16> aidl2legacy_string_view_String16(std::string_view aidl);
-ConversionResult<std::string> legacy2aidl_String16_string(const String16& legacy);
-
-ConversionResult<std::optional<String16>>
-aidl2legacy_optional_string_view_optional_String16(std::optional<std::string_view> aidl);
-ConversionResult<std::optional<std::string_view>>
-legacy2aidl_optional_String16_optional_string(std::optional<String16> legacy);
-
-ConversionResult<audio_channel_mask_t> aidl2legacy_AudioChannelLayout_audio_channel_mask_t(
-        const media::audio::common::AudioChannelLayout& aidl, bool isInput);
-ConversionResult<media::audio::common::AudioChannelLayout>
-legacy2aidl_audio_channel_mask_t_AudioChannelLayout(audio_channel_mask_t legacy, bool isInput);
-
-audio_channel_mask_t aidl2legacy_AudioChannelLayout_layout_audio_channel_mask_t_bits(
-        int aidlLayout, bool isInput);
-int legacy2aidl_audio_channel_mask_t_bits_AudioChannelLayout_layout(
-        audio_channel_mask_t legacy, bool isInput);
-
-enum class AudioPortDirection {
-    INPUT, OUTPUT
-};
-ConversionResult<AudioPortDirection> portDirection(audio_port_role_t role, audio_port_type_t type);
-ConversionResult<audio_port_role_t> portRole(AudioPortDirection direction, audio_port_type_t type);
-
-ConversionResult<audio_config_t>
-aidl2legacy_AudioConfig_audio_config_t(const media::audio::common::AudioConfig& aidl, bool isInput);
-ConversionResult<media::audio::common::AudioConfig>
-legacy2aidl_audio_config_t_AudioConfig(const audio_config_t& legacy, bool isInput);
-
-ConversionResult<audio_config_base_t>
-aidl2legacy_AudioConfigBase_audio_config_base_t(
-        const media::audio::common::AudioConfigBase& aidl, bool isInput);
-ConversionResult<media::audio::common::AudioConfigBase>
-legacy2aidl_audio_config_base_t_AudioConfigBase(const audio_config_base_t& legacy, bool isInput);
-
-ConversionResult<audio_input_flags_t>
-aidl2legacy_AudioInputFlags_audio_input_flags_t(media::audio::common::AudioInputFlags aidl);
-ConversionResult<media::audio::common::AudioInputFlags>
-legacy2aidl_audio_input_flags_t_AudioInputFlags(audio_input_flags_t legacy);
-
-ConversionResult<audio_output_flags_t>
-aidl2legacy_AudioOutputFlags_audio_output_flags_t(media::audio::common::AudioOutputFlags aidl);
-ConversionResult<media::audio::common::AudioOutputFlags>
-legacy2aidl_audio_output_flags_t_AudioOutputFlags(audio_output_flags_t legacy);
-
-ConversionResult<audio_input_flags_t> aidl2legacy_int32_t_audio_input_flags_t_mask(
-        int32_t aidl);
-ConversionResult<int32_t> legacy2aidl_audio_input_flags_t_int32_t_mask(
-        audio_input_flags_t legacy);
-
-ConversionResult<audio_output_flags_t> aidl2legacy_int32_t_audio_output_flags_t_mask(
-        int32_t aidl);
-ConversionResult<int32_t> legacy2aidl_audio_output_flags_t_int32_t_mask(
-        audio_output_flags_t legacy);
-
-ConversionResult<audio_io_flags> aidl2legacy_AudioIoFlags_audio_io_flags(
-        const media::audio::common::AudioIoFlags& aidl, bool isInput);
-ConversionResult<media::audio::common::AudioIoFlags> legacy2aidl_audio_io_flags_AudioIoFlags(
-        const audio_io_flags& legacy, bool isInput);
-
-ConversionResult<audio_session_t> aidl2legacy_int32_t_audio_session_t(int32_t aidl);
-ConversionResult<int32_t> legacy2aidl_audio_session_t_int32_t(audio_session_t legacy);
-
-ConversionResult<audio_content_type_t>
-aidl2legacy_AudioContentType_audio_content_type_t(
-        media::audio::common::AudioContentType aidl);
-ConversionResult<media::audio::common::AudioContentType>
-legacy2aidl_audio_content_type_t_AudioContentType(audio_content_type_t legacy);
-
-ConversionResult<audio_devices_t> aidl2legacy_AudioDeviceDescription_audio_devices_t(
-        const media::audio::common::AudioDeviceDescription& aidl);
-ConversionResult<media::audio::common::AudioDeviceDescription>
-legacy2aidl_audio_devices_t_AudioDeviceDescription(audio_devices_t legacy);
-
-status_t aidl2legacy_AudioDevice_audio_device(
-        const media::audio::common::AudioDevice& aidl, audio_devices_t* legacyType,
-        char* legacyAddress);
-status_t aidl2legacy_AudioDevice_audio_device(
-        const media::audio::common::AudioDevice& aidl, audio_devices_t* legacyType,
-        String8* legacyAddress);
-status_t aidl2legacy_AudioDevice_audio_device(
-        const media::audio::common::AudioDevice& aidl, audio_devices_t* legacyType,
-        std::string* legacyAddress);
-
-ConversionResult<media::audio::common::AudioDevice> legacy2aidl_audio_device_AudioDevice(
-        audio_devices_t legacyType, const char* legacyAddress);
-ConversionResult<media::audio::common::AudioDevice> legacy2aidl_audio_device_AudioDevice(
-        audio_devices_t legacyType, const String8& legacyAddress);
-
-ConversionResult<audio_extra_audio_descriptor>
-aidl2legacy_ExtraAudioDescriptor_audio_extra_audio_descriptor(
-        const media::audio::common::ExtraAudioDescriptor& aidl);
-
-ConversionResult<media::audio::common::ExtraAudioDescriptor>
-legacy2aidl_audio_extra_audio_descriptor_ExtraAudioDescriptor(
-        const audio_extra_audio_descriptor& legacy);
-
-ConversionResult<audio_encapsulation_metadata_type_t>
-aidl2legacy_AudioEncapsulationMetadataType_audio_encapsulation_metadata_type_t(
-        media::audio::common::AudioEncapsulationMetadataType aidl);
-ConversionResult<media::audio::common::AudioEncapsulationMetadataType>
-legacy2aidl_audio_encapsulation_metadata_type_t_AudioEncapsulationMetadataType(
-        audio_encapsulation_metadata_type_t legacy);
-
-ConversionResult<uint32_t> aidl2legacy_AudioEncapsulationMetadataType_mask(int32_t aidl);
-ConversionResult<int32_t> legacy2aidl_AudioEncapsulationMetadataType_mask(uint32_t legacy);
-
-ConversionResult<audio_encapsulation_mode_t>
-aidl2legacy_AudioEncapsulationMode_audio_encapsulation_mode_t(
-        media::audio::common::AudioEncapsulationMode aidl);
-ConversionResult<media::audio::common::AudioEncapsulationMode>
-legacy2aidl_audio_encapsulation_mode_t_AudioEncapsulationMode(audio_encapsulation_mode_t legacy);
-
-ConversionResult<uint32_t> aidl2legacy_AudioEncapsulationMode_mask(int32_t aidl);
-ConversionResult<int32_t> legacy2aidl_AudioEncapsulationMode_mask(uint32_t legacy);
-
-ConversionResult<audio_encapsulation_type_t>
-aidl2legacy_AudioEncapsulationType_audio_encapsulation_type_t(
-        const media::audio::common::AudioEncapsulationType& aidl);
-ConversionResult<media::audio::common::AudioEncapsulationType>
-legacy2aidl_audio_encapsulation_type_t_AudioEncapsulationType(
-        const audio_encapsulation_type_t& legacy);
-
-ConversionResult<audio_format_t> aidl2legacy_AudioFormatDescription_audio_format_t(
-        const media::audio::common::AudioFormatDescription& aidl);
-ConversionResult<media::audio::common::AudioFormatDescription>
-legacy2aidl_audio_format_t_AudioFormatDescription(audio_format_t legacy);
-
-ConversionResult<audio_gain_mode_t>
-aidl2legacy_AudioGainMode_audio_gain_mode_t(media::audio::common::AudioGainMode aidl);
-ConversionResult<media::audio::common::AudioGainMode>
-legacy2aidl_audio_gain_mode_t_AudioGainMode(audio_gain_mode_t legacy);
-
-ConversionResult<audio_gain_mode_t> aidl2legacy_int32_t_audio_gain_mode_t_mask(int32_t aidl);
-ConversionResult<int32_t> legacy2aidl_audio_gain_mode_t_int32_t_mask(audio_gain_mode_t legacy);
-
-ConversionResult<audio_gain_config> aidl2legacy_AudioGainConfig_audio_gain_config(
-        const media::audio::common::AudioGainConfig& aidl, bool isInput);
-ConversionResult<media::audio::common::AudioGainConfig>
-legacy2aidl_audio_gain_config_AudioGainConfig(const audio_gain_config& legacy, bool isInput);
-
-ConversionResult<audio_gain>
-aidl2legacy_AudioGain_audio_gain(const media::audio::common::AudioGain& aidl, bool isInput);
-ConversionResult<media::audio::common::AudioGain>
-legacy2aidl_audio_gain_AudioGain(const audio_gain& legacy, bool isInput);
-
-ConversionResult<audio_input_flags_t>
-aidl2legacy_AudioInputFlags_audio_input_flags_t(media::audio::common::AudioInputFlags aidl);
-ConversionResult<media::audio::common::AudioInputFlags>
-legacy2aidl_audio_input_flags_t_AudioInputFlags(audio_input_flags_t legacy);
-
-ConversionResult<audio_mode_t>
-aidl2legacy_AudioMode_audio_mode_t(media::audio::common::AudioMode aidl);
-ConversionResult<media::audio::common::AudioMode>
-legacy2aidl_audio_mode_t_AudioMode(audio_mode_t legacy);
-
-ConversionResult<audio_offload_info_t>
-aidl2legacy_AudioOffloadInfo_audio_offload_info_t(
-        const media::audio::common::AudioOffloadInfo& aidl);
-ConversionResult<media::audio::common::AudioOffloadInfo>
-legacy2aidl_audio_offload_info_t_AudioOffloadInfo(const audio_offload_info_t& legacy);
-
-ConversionResult<audio_output_flags_t>
-aidl2legacy_AudioOutputFlags_audio_output_flags_t(media::audio::common::AudioOutputFlags aidl);
-ConversionResult<media::audio::common::AudioOutputFlags>
-legacy2aidl_audio_output_flags_t_AudioOutputFlags(audio_output_flags_t legacy);
-
-// This type is unnamed in the original definition, thus we name it here.
-using audio_port_config_mix_ext_usecase = decltype(audio_port_config_mix_ext::usecase);
-ConversionResult<audio_port_config_mix_ext_usecase>
-aidl2legacy_AudioPortMixExtUseCase_audio_port_config_mix_ext_usecase(
-        const media::audio::common::AudioPortMixExtUseCase& aidl, bool isInput);
-ConversionResult<media::audio::common::AudioPortMixExtUseCase>
-legacy2aidl_audio_port_config_mix_ext_usecase_AudioPortMixExtUseCase(
-        const audio_port_config_mix_ext_usecase& legacy, bool isInput);
-
-ConversionResult<audio_port_config_device_ext>
-aidl2legacy_AudioPortDeviceExt_audio_port_config_device_ext(
-        const media::audio::common::AudioPortDeviceExt& aidl);
-ConversionResult<media::audio::common::AudioPortDeviceExt>
-        legacy2aidl_audio_port_config_device_ext_AudioPortDeviceExt(
-        const audio_port_config_device_ext& legacy);
-
-status_t aidl2legacy_AudioPortConfig_audio_port_config(
-        const media::audio::common::AudioPortConfig& aidl, bool isInput,
-        audio_port_config* legacy, int32_t* portId);
-ConversionResult<media::audio::common::AudioPortConfig>
-legacy2aidl_audio_port_config_AudioPortConfig(
-        const audio_port_config& legacy, bool isInput, int32_t portId);
-
-ConversionResult<audio_port_mix_ext> aidl2legacy_AudioPortMixExt_audio_port_mix_ext(
-        const media::audio::common::AudioPortMixExt& aidl);
-ConversionResult<media::audio::common::AudioPortMixExt>
-legacy2aidl_audio_port_mix_ext_AudioPortMixExt(
-        const audio_port_mix_ext& legacy);
-
-ConversionResult<audio_port_device_ext>
-aidl2legacy_AudioPortDeviceExt_audio_port_device_ext(
-        const media::audio::common::AudioPortDeviceExt& aidl);
-ConversionResult<media::audio::common::AudioPortDeviceExt>
-legacy2aidl_audio_port_device_ext_AudioPortDeviceExt(
-        const audio_port_device_ext& legacy);
-
-ConversionResult<audio_port_v7>
-aidl2legacy_AudioPort_audio_port_v7(
-        const media::audio::common::AudioPort& aidl, bool isInput);
-ConversionResult<media::audio::common::AudioPort>
-legacy2aidl_audio_port_v7_AudioPort(const audio_port_v7& legacy, bool isInput);
-
-ConversionResult<audio_profile> aidl2legacy_AudioProfile_audio_profile(
-        const media::audio::common::AudioProfile& aidl, bool isInput);
-ConversionResult<media::audio::common::AudioProfile> legacy2aidl_audio_profile_AudioProfile(
-        const audio_profile& legacy, bool isInput);
-
-ConversionResult<audio_standard_t> aidl2legacy_AudioStandard_audio_standard_t(
-        media::audio::common::AudioStandard aidl);
-ConversionResult<media::audio::common::AudioStandard> legacy2aidl_audio_standard_t_AudioStandard(
-        audio_standard_t legacy);
-
-ConversionResult<audio_source_t> aidl2legacy_AudioSource_audio_source_t(
-        media::audio::common::AudioSource aidl);
-ConversionResult<media::audio::common::AudioSource> legacy2aidl_audio_source_t_AudioSource(
-        audio_source_t legacy);
-
-ConversionResult<audio_usage_t> aidl2legacy_AudioUsage_audio_usage_t(
-        media::audio::common::AudioUsage aidl);
-ConversionResult<media::audio::common::AudioUsage> legacy2aidl_audio_usage_t_AudioUsage(
-        audio_usage_t legacy);
-
-ConversionResult<audio_uuid_t> aidl2legacy_AudioUuid_audio_uuid_t(
-        const media::audio::common::AudioUuid &aidl);
-ConversionResult<media::audio::common::AudioUuid> legacy2aidl_audio_uuid_t_AudioUuid(
-        const audio_uuid_t& legacy);
-
-ConversionResult<audio_dual_mono_mode_t>
-aidl2legacy_AudioDualMonoMode_audio_dual_mono_mode_t(media::audio::common::AudioDualMonoMode aidl);
-ConversionResult<media::audio::common::AudioDualMonoMode>
-legacy2aidl_audio_dual_mono_mode_t_AudioDualMonoMode(audio_dual_mono_mode_t legacy);
-
-ConversionResult<audio_timestretch_fallback_mode_t>
-aidl2legacy_TimestretchFallbackMode_audio_timestretch_fallback_mode_t(
-        media::audio::common::AudioPlaybackRate::TimestretchFallbackMode aidl);
-ConversionResult<media::audio::common::AudioPlaybackRate::TimestretchFallbackMode>
-legacy2aidl_audio_timestretch_fallback_mode_t_TimestretchFallbackMode(
-        audio_timestretch_fallback_mode_t legacy);
-
-ConversionResult<audio_timestretch_stretch_mode_t>
-aidl2legacy_TimestretchMode_audio_timestretch_stretch_mode_t(
-        media::audio::common::AudioPlaybackRate::TimestretchMode aidl);
-ConversionResult<media::audio::common::AudioPlaybackRate::TimestretchMode>
-legacy2aidl_audio_timestretch_stretch_mode_t_TimestretchMode(
-        audio_timestretch_stretch_mode_t legacy);
-
-ConversionResult<audio_playback_rate_t>
-aidl2legacy_AudioPlaybackRate_audio_playback_rate_t(
-        const media::audio::common::AudioPlaybackRate& aidl);
-ConversionResult<media::audio::common::AudioPlaybackRate>
-legacy2aidl_audio_playback_rate_t_AudioPlaybackRate(const audio_playback_rate_t& legacy);
-
-ConversionResult<audio_latency_mode_t>
-aidl2legacy_AudioLatencyMode_audio_latency_mode_t(media::audio::common::AudioLatencyMode aidl);
-ConversionResult<media::audio::common::AudioLatencyMode>
-legacy2aidl_audio_latency_mode_t_AudioLatencyMode(audio_latency_mode_t legacy);
-
-ConversionResult<audio_microphone_location_t>
-aidl2legacy_MicrophoneInfoLocation_audio_microphone_location_t(
-        media::audio::common::MicrophoneInfo::Location aidl);
-ConversionResult<media::audio::common::MicrophoneInfo::Location>
-legacy2aidl_audio_microphone_location_t_MicrophoneInfoLocation(audio_microphone_location_t legacy);
-
-ConversionResult<audio_microphone_group_t> aidl2legacy_int32_t_audio_microphone_group_t(
-        int32_t aidl);
-ConversionResult<int32_t> legacy2aidl_audio_microphone_group_t_int32_t(
-        audio_microphone_group_t legacy);
-
-ConversionResult<audio_microphone_directionality_t>
-aidl2legacy_MicrophoneInfoDirectionality_audio_microphone_directionality_t(
-        media::audio::common::MicrophoneInfo::Directionality aidl);
-ConversionResult<media::audio::common::MicrophoneInfo::Directionality>
-legacy2aidl_audio_microphone_directionality_t_MicrophoneInfoDirectionality(
-        audio_microphone_directionality_t legacy);
-
-ConversionResult<audio_microphone_coordinate>
-aidl2legacy_MicrophoneInfoCoordinate_audio_microphone_coordinate(
-        const media::audio::common::MicrophoneInfo::Coordinate& aidl);
-ConversionResult<media::audio::common::MicrophoneInfo::Coordinate>
-legacy2aidl_audio_microphone_coordinate_MicrophoneInfoCoordinate(
-        const audio_microphone_coordinate& legacy);
-
-ConversionResult<audio_microphone_channel_mapping_t>
-aidl2legacy_MicrophoneDynamicInfoChannelMapping_audio_microphone_channel_mapping_t(
-        media::audio::common::MicrophoneDynamicInfo::ChannelMapping aidl);
-ConversionResult<media::audio::common::MicrophoneDynamicInfo::ChannelMapping>
-legacy2aidl_audio_microphone_channel_mapping_t_MicrophoneDynamicInfoChannelMapping(
-        audio_microphone_channel_mapping_t legacy);
-
-ConversionResult<audio_microphone_characteristic_t>
-aidl2legacy_MicrophoneInfos_audio_microphone_characteristic_t(
-        const media::audio::common::MicrophoneInfo& aidlInfo,
-        const media::audio::common::MicrophoneDynamicInfo& aidlDynamic);
-status_t
-legacy2aidl_audio_microphone_characteristic_t_MicrophoneInfos(
-        const audio_microphone_characteristic_t& legacy,
-        media::audio::common::MicrophoneInfo* aidlInfo,
-        media::audio::common::MicrophoneDynamicInfo* aidlDynamic);
-
-}  // namespace android
-
-#if defined(BACKEND_NDK)
-} // aidl
+#if defined(BACKEND_CPP_NDK) || !defined(BACKEND_NDK)
+#include <media/AidlConversionCppNdk-impl.h>
 #endif
diff --git a/media/audioaidlconversion/include/media/AidlConversionUtil-impl.h b/media/audioaidlconversion/include/media/AidlConversionUtil-impl.h
new file mode 100644
index 0000000..ed91e2c
--- /dev/null
+++ b/media/audioaidlconversion/include/media/AidlConversionUtil-impl.h
@@ -0,0 +1,438 @@
+/*
+ * Copyright (C) 2023 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.
+ */
+
+// WARNING: This file is intended for multiple inclusion, one time
+// with BACKEND_NDK_IMPL defined, one time without it.
+// Do not include directly, use 'AidlConversionUtil.h'.
+#if (defined(BACKEND_NDK_IMPL) && !defined(AUDIO_AIDL_CONVERSION_AIDL_CONVERSION_UTIL_NDK)) || \
+    (!defined(BACKEND_NDK_IMPL) && !defined(AUDIO_AIDL_CONVERSION_AIDL_CONVERSION_UTIL_CPP))
+#if defined(BACKEND_NDK_IMPL)
+#define AUDIO_AIDL_CONVERSION_AIDL_CONVERSION_UTIL_NDK
+#else
+#define AUDIO_AIDL_CONVERSION_AIDL_CONVERSION_UTIL_CPP
+#endif  // BACKEND_NDK_IMPL
+
+#include <limits>
+#include <type_traits>
+#include <utility>
+
+#include <android-base/expected.h>
+#include <binder/Status.h>
+
+#if defined(BACKEND_NDK_IMPL)
+#include <android/binder_auto_utils.h>
+#include <android/binder_enums.h>
+#include <android/binder_status.h>
+
+namespace aidl {
+#else
+#include <binder/Enums.h>
+#endif  // BACKEND_NDK_IMPL
+namespace android {
+
+#if defined(BACKEND_NDK_IMPL)
+// This adds `::aidl::android::ConversionResult` for convenience.
+// Otherwise, it would be required to write `::android::ConversionResult` everywhere.
+template <typename T>
+using ConversionResult = ::android::ConversionResult<T>;
+#endif  // BACKEND_NDK_IMPL
+
+/**
+ * A generic template to safely cast between integral types, respecting limits of the destination
+ * type.
+ */
+template<typename To, typename From>
+ConversionResult<To> convertIntegral(From from) {
+    // Special handling is required for signed / vs. unsigned comparisons, since otherwise we may
+    // have the signed converted to unsigned and produce wrong results.
+    if (std::is_signed_v<From> && !std::is_signed_v<To>) {
+        if (from < 0 || from > std::numeric_limits<To>::max()) {
+            return ::android::base::unexpected(::android::BAD_VALUE);
+        }
+    } else if (std::is_signed_v<To> && !std::is_signed_v<From>) {
+        if (from > std::numeric_limits<To>::max()) {
+            return ::android::base::unexpected(::android::BAD_VALUE);
+        }
+    } else {
+        if (from < std::numeric_limits<To>::min() || from > std::numeric_limits<To>::max()) {
+            return ::android::base::unexpected(::android::BAD_VALUE);
+        }
+    }
+    return static_cast<To>(from);
+}
+
+/**
+ * A generic template to safely cast between types, that are intended to be the same size, but
+ * interpreted differently.
+ */
+template<typename To, typename From>
+ConversionResult<To> convertReinterpret(From from) {
+    static_assert(sizeof(From) == sizeof(To));
+    return static_cast<To>(from);
+}
+
+/**
+ * A generic template that helps convert containers of convertible types, using iterators.
+ */
+template<typename InputIterator, typename OutputIterator, typename Func>
+::android::status_t convertRange(InputIterator start,
+                      InputIterator end,
+                      OutputIterator out,
+                      const Func& itemConversion) {
+    for (InputIterator iter = start; iter != end; ++iter, ++out) {
+        *out = VALUE_OR_RETURN_STATUS(itemConversion(*iter));
+    }
+    return ::android::OK;
+}
+
+/**
+ * A generic template that helps convert containers of convertible types, using iterators.
+ * Uses a limit as maximum conversion items.
+ */
+template<typename InputIterator, typename OutputIterator, typename Func>
+::android::status_t convertRangeWithLimit(InputIterator start,
+                      InputIterator end,
+                      OutputIterator out,
+                      const Func& itemConversion,
+                      const size_t limit) {
+    InputIterator last = end;
+    if (end - start > limit) {
+        last = start + limit;
+    }
+    for (InputIterator iter = start; (iter != last); ++iter, ++out) {
+        *out = VALUE_OR_RETURN_STATUS(itemConversion(*iter));
+    }
+    return ::android::OK;
+}
+
+/**
+ * A generic template that helps convert containers of convertible types.
+ */
+template<typename OutputContainer, typename InputContainer, typename Func>
+ConversionResult<OutputContainer>
+convertContainer(const InputContainer& input, const Func& itemConversion) {
+    OutputContainer output;
+    auto ins = std::inserter(output, output.begin());
+    for (const auto& item : input) {
+        *ins = VALUE_OR_RETURN(itemConversion(item));
+    }
+    return output;
+}
+
+/**
+ * A generic template that helps convert containers of convertible types
+ * using an item conversion function with an additional parameter.
+ */
+template<typename OutputContainer, typename InputContainer, typename Func, typename Parameter>
+ConversionResult<OutputContainer>
+convertContainer(const InputContainer& input, const Func& itemConversion, const Parameter& param) {
+    OutputContainer output;
+    auto ins = std::inserter(output, output.begin());
+    for (const auto& item : input) {
+        *ins = VALUE_OR_RETURN(itemConversion(item, param));
+    }
+    return output;
+}
+
+/**
+ * A generic template that helps to "zip" two input containers of the same size
+ * into a single vector of converted types. The conversion function must
+ * thus accept two arguments.
+ */
+template<typename OutputContainer, typename InputContainer1,
+        typename InputContainer2, typename Func>
+ConversionResult<OutputContainer>
+convertContainers(const InputContainer1& input1, const InputContainer2& input2,
+        const Func& itemConversion) {
+    auto iter2 = input2.begin();
+    OutputContainer output;
+    auto ins = std::inserter(output, output.begin());
+    for (const auto& item1 : input1) {
+        RETURN_IF_ERROR(iter2 != input2.end() ? ::android::OK : ::android::BAD_VALUE);
+        *ins = VALUE_OR_RETURN(itemConversion(item1, *iter2++));
+    }
+    return output;
+}
+
+/**
+ * A generic template that helps to "unzip" a per-element conversion into
+ * a pair of elements into a pair of containers. The conversion function
+ * must emit a pair of elements.
+ */
+template<typename OutputContainer1, typename OutputContainer2,
+        typename InputContainer, typename Func>
+ConversionResult<std::pair<OutputContainer1, OutputContainer2>>
+convertContainerSplit(const InputContainer& input, const Func& itemConversion) {
+    OutputContainer1 output1;
+    OutputContainer2 output2;
+    auto ins1 = std::inserter(output1, output1.begin());
+    auto ins2 = std::inserter(output2, output2.begin());
+    for (const auto& item : input) {
+        auto out_pair = VALUE_OR_RETURN(itemConversion(item));
+        *ins1 = out_pair.first;
+        *ins2 = out_pair.second;
+    }
+    return std::make_pair(output1, output2);
+}
+
+////////////////////////////////////////////////////////////////////////////////////////////////////
+// The code below establishes:
+// IntegralTypeOf<T>, which works for either integral types (in which case it evaluates to T), or
+// enum types (in which case it evaluates to std::underlying_type_T<T>).
+
+template<typename T, typename = std::enable_if_t<std::is_integral_v<T> || std::is_enum_v<T>>>
+struct IntegralTypeOfStruct {
+    using Type = T;
+};
+
+template<typename T>
+struct IntegralTypeOfStruct<T, std::enable_if_t<std::is_enum_v<T>>> {
+    using Type = std::underlying_type_t<T>;
+};
+
+template<typename T>
+using IntegralTypeOf = typename IntegralTypeOfStruct<T>::Type;
+
+////////////////////////////////////////////////////////////////////////////////////////////////////
+// Utilities for handling bitmasks.
+
+template<typename Enum>
+Enum indexToEnum_index(int index) {
+    static_assert(std::is_enum_v<Enum> || std::is_integral_v<Enum>);
+    return static_cast<Enum>(index);
+}
+
+template<typename Enum>
+Enum indexToEnum_bitmask(int index) {
+    static_assert(std::is_enum_v<Enum> || std::is_integral_v<Enum>);
+    return static_cast<Enum>(1 << index);
+}
+
+template<typename Mask, typename Enum>
+Mask enumToMask_bitmask(Enum e) {
+    static_assert(std::is_enum_v<Enum> || std::is_integral_v<Enum>);
+    static_assert(std::is_enum_v<Mask> || std::is_integral_v<Mask>);
+    return static_cast<Mask>(e);
+}
+
+template<typename Mask, typename Enum>
+Mask enumToMask_index(Enum e) {
+    static_assert(std::is_enum_v<Enum> || std::is_integral_v<Enum>);
+    static_assert(std::is_enum_v<Mask> || std::is_integral_v<Mask>);
+    return static_cast<Mask>(static_cast<std::make_unsigned_t<IntegralTypeOf<Mask>>>(1)
+            << static_cast<int>(e));
+}
+
+template<typename DestMask, typename SrcMask, typename DestEnum, typename SrcEnum>
+ConversionResult<DestMask> convertBitmask(
+        SrcMask src, const std::function<ConversionResult<DestEnum>(SrcEnum)>& enumConversion,
+        const std::function<SrcEnum(int)>& srcIndexToEnum,
+        const std::function<DestMask(DestEnum)>& destEnumToMask) {
+    using UnsignedDestMask = std::make_unsigned_t<IntegralTypeOf<DestMask>>;
+    using UnsignedSrcMask = std::make_unsigned_t<IntegralTypeOf<SrcMask>>;
+
+    UnsignedDestMask dest = static_cast<UnsignedDestMask>(0);
+    UnsignedSrcMask usrc = static_cast<UnsignedSrcMask>(src);
+
+    int srcBitIndex = 0;
+    while (usrc != 0) {
+        if (usrc & 1) {
+            SrcEnum srcEnum = srcIndexToEnum(srcBitIndex);
+            DestEnum destEnum = VALUE_OR_RETURN(enumConversion(srcEnum));
+            DestMask destMask = destEnumToMask(destEnum);
+            dest |= destMask;
+        }
+        ++srcBitIndex;
+        usrc >>= 1;
+    }
+    return static_cast<DestMask>(dest);
+}
+
+template<typename Mask, typename Enum>
+bool bitmaskIsSet(Mask mask, Enum index) {
+    return (mask & enumToMask_index<Mask, Enum>(index)) != 0;
+}
+
+////////////////////////////////////////////////////////////////////////////////////////////////////
+// Utilities for working with AIDL unions.
+// UNION_GET(obj, fieldname) returns a ConversionResult<T> containing either the strongly-typed
+//   value of the respective field, or ::android::BAD_VALUE if the union is not set to the requested
+//   field.
+// UNION_SET(obj, fieldname, value) sets the requested field to the given value.
+
+template<typename T, typename T::Tag tag>
+using UnionFieldType = std::decay_t<decltype(std::declval<T>().template get<tag>())>;
+
+template<typename T, typename T::Tag tag>
+ConversionResult<UnionFieldType<T, tag>> unionGetField(const T& u) {
+    if (u.getTag() != tag) {
+        return ::android::base::unexpected(::android::BAD_VALUE);
+    }
+    return u.template get<tag>();
+}
+
+#define UNION_GET(u, field) \
+    unionGetField<std::decay_t<decltype(u)>, std::decay_t<decltype(u)>::Tag::field>(u)
+
+#define UNION_SET(u, field, value) \
+    (u).set<std::decay_t<decltype(u)>::Tag::field>(value)
+
+#define UNION_MAKE(u, field, value) u::make<u::Tag::field>(value)
+
+namespace aidl_utils {
+
+/**
+ * Return true if the value is valid for the AIDL enumeration.
+ */
+template <typename T>
+bool isValidEnum(T value) {
+#if defined(BACKEND_NDK_IMPL)
+    constexpr ndk::enum_range<T> er{};
+#else
+    constexpr ::android::enum_range<T> er{};
+#endif
+    return std::find(er.begin(), er.end(), value) != er.end();
+}
+
+// T is a "container" of enum binder types with a toString().
+template <typename T>
+std::string enumsToString(const T& t) {
+    std::string s;
+    for (const auto item : t) {
+        if (s.empty()) {
+            s = toString(item);
+        } else {
+            s.append("|").append(toString(item));
+        }
+    }
+    return s;
+}
+
+/**
+ * Return the equivalent Android ::android::status_t from a binder exception code.
+ *
+ * Generally one should use statusTFromBinderStatus() instead.
+ *
+ * Exception codes can be generated from a remote Java service exception, translate
+ * them for use on the Native side.
+ *
+ * Note: for EX_TRANSACTION_FAILED and EX_SERVICE_SPECIFIC a more detailed error code
+ * can be found from transactionError() or serviceSpecificErrorCode().
+ */
+static inline ::android::status_t statusTFromExceptionCode(int32_t exceptionCode) {
+    using namespace ::android::binder;
+    switch (exceptionCode) {
+        case Status::EX_NONE:
+            return ::android::OK;
+        case Status::EX_SECURITY:  // Java SecurityException, rethrows locally in Java
+            return ::android::PERMISSION_DENIED;
+        case Status::EX_BAD_PARCELABLE:  // Java BadParcelableException, rethrows in Java
+        case Status::EX_ILLEGAL_ARGUMENT:  // Java IllegalArgumentException, rethrows in Java
+        case Status::EX_NULL_POINTER:  // Java NullPointerException, rethrows in Java
+            return ::android::BAD_VALUE;
+        case Status::EX_ILLEGAL_STATE:  // Java IllegalStateException, rethrows in Java
+        case Status::EX_UNSUPPORTED_OPERATION:  // Java UnsupportedOperationException, rethrows
+            return ::android::INVALID_OPERATION;
+        case Status::EX_HAS_REPLY_HEADER: // Native strictmode violation
+        case Status::EX_PARCELABLE:  // Java bootclass loader (not standard exception), rethrows
+        case Status::EX_NETWORK_MAIN_THREAD:  // Java NetworkOnMainThreadException, rethrows
+        case Status::EX_TRANSACTION_FAILED: // Native - see error code
+        case Status::EX_SERVICE_SPECIFIC:   // Java ServiceSpecificException,
+                                            // rethrows in Java with integer error code
+            return ::android::UNKNOWN_ERROR;
+    }
+    return ::android::UNKNOWN_ERROR;
+}
+
+/**
+ * Return the equivalent Android ::android::status_t from a binder status.
+ *
+ * Used to handle errors from a AIDL method declaration
+ *
+ * [oneway] void method(type0 param0, ...)
+ *
+ * or the following (where return_type is not a status_t)
+ *
+ * return_type method(type0 param0, ...)
+ */
+static inline ::android::status_t statusTFromBinderStatus(const ::android::binder::Status &status) {
+    return status.isOk() ? ::android::OK // check ::android::OK,
+        : status.serviceSpecificErrorCode() // service-side error, not standard Java exception
+                                            // (fromServiceSpecificError)
+        ?: status.transactionError() // a native binder transaction error (fromStatusT)
+        ?: statusTFromExceptionCode(status.exceptionCode()); // a service-side error with a
+                                                    // standard Java exception (fromExceptionCode)
+}
+
+#if defined(BACKEND_NDK_IMPL)
+static inline ::android::status_t statusTFromBinderStatus(const ::ndk::ScopedAStatus &status) {
+    // What we want to do is to 'return statusTFromBinderStatus(status.get()->get())'
+    // However, since the definition of AStatus is not exposed, we have to do the same
+    // via methods of ScopedAStatus:
+    return status.isOk() ? ::android::OK // check ::android::OK,
+        : status.getServiceSpecificError() // service-side error, not standard Java exception
+                                           // (fromServiceSpecificError)
+        ?: status.getStatus() // a native binder transaction error (fromStatusT)
+        ?: statusTFromExceptionCode(status.getExceptionCode()); // a service-side error with a
+                                                     // standard Java exception (fromExceptionCode)
+}
+#endif
+
+/**
+ * Return a binder::Status from native service status.
+ *
+ * This is used for methods not returning an explicit status_t,
+ * where Java callers expect an exception, not an integer return value.
+ */
+static inline ::android::binder::Status binderStatusFromStatusT(
+        ::android::status_t status, const char *optionalMessage = nullptr) {
+    const char * const emptyIfNull = optionalMessage == nullptr ? "" : optionalMessage;
+    // From binder::Status instructions:
+    //  Prefer a generic exception code when possible, then a service specific
+    //  code, and finally a ::android::status_t for low level failures or legacy support.
+    //  Exception codes and service specific errors map to nicer exceptions for
+    //  Java clients.
+
+    using namespace ::android::binder;
+    switch (status) {
+        case ::android::OK:
+            return Status::ok();
+        case ::android::PERMISSION_DENIED: // throw SecurityException on Java side
+            return Status::fromExceptionCode(Status::EX_SECURITY, emptyIfNull);
+        case ::android::BAD_VALUE: // throw IllegalArgumentException on Java side
+            return Status::fromExceptionCode(Status::EX_ILLEGAL_ARGUMENT, emptyIfNull);
+        case ::android::INVALID_OPERATION: // throw IllegalStateException on Java side
+            return Status::fromExceptionCode(Status::EX_ILLEGAL_STATE, emptyIfNull);
+    }
+
+    // A service specific error will not show on status.transactionError() so
+    // be sure to use statusTFromBinderStatus() for reliable error handling.
+
+    // throw a ServiceSpecificException.
+    return Status::fromServiceSpecificError(status, emptyIfNull);
+}
+
+} // namespace aidl_utils
+
+}  // namespace android
+
+#if defined(BACKEND_NDK_IMPL)
+}  // namespace aidl
+#endif
+
+// (defined(BACKEND_NDK_IMPL) && !defined(AUDIO_AIDL_CONVERSION_AIDL_CONVERSION_UTIL_NDK)) || \
+// (!defined(BACKEND_NDK_IMPL) && !defined(AUDIO_AIDL_CONVERSION_AIDL_CONVERSION_UTIL_CPP))
+#endif
diff --git a/media/audioaidlconversion/include/media/AidlConversionUtil.h b/media/audioaidlconversion/include/media/AidlConversionUtil.h
index 8469f44..b846436 100644
--- a/media/audioaidlconversion/include/media/AidlConversionUtil.h
+++ b/media/audioaidlconversion/include/media/AidlConversionUtil.h
@@ -16,12 +16,6 @@
 
 #pragma once
 
-#include <limits>
-#include <type_traits>
-#include <utility>
-
-#include <android-base/expected.h>
-#include <binder/Status.h>
 #include <error/Result.h>
 
 namespace android {
@@ -32,403 +26,16 @@
 using ConversionResult = ::android::error::Result<T>;
 }  // namespace android
 
-#if defined(BACKEND_NDK)
-#include <android/binder_auto_utils.h>
-#include <android/binder_enums.h>
-#include <android/binder_status.h>
+// Include 'AidlConversionUtil.h' once if 'BACKEND_NDK' is defined,
+// or no 'BACKEND_*' is defined (C++ backend). Include twice if
+// 'BACKEND_CPP_NDK' is defined: once with 'BACKEND_NDK_IMPL', once w/o defines.
 
-namespace aidl {
-#else
-#include <binder/Enums.h>
-#endif  // BACKEND_NDK
-namespace android {
-
-#if defined(BACKEND_NDK)
-// This adds `::aidl::android::ConversionResult` for convenience.
-// Otherwise, it would be required to write `::android::ConversionResult` everywhere.
-template <typename T>
-using ConversionResult = ::android::ConversionResult<T>;
-#endif  // BACKEND_NDK
-
-/**
- * A generic template to safely cast between integral types, respecting limits of the destination
- * type.
- */
-template<typename To, typename From>
-ConversionResult<To> convertIntegral(From from) {
-    // Special handling is required for signed / vs. unsigned comparisons, since otherwise we may
-    // have the signed converted to unsigned and produce wrong results.
-    if (std::is_signed_v<From> && !std::is_signed_v<To>) {
-        if (from < 0 || from > std::numeric_limits<To>::max()) {
-            return ::android::base::unexpected(::android::BAD_VALUE);
-        }
-    } else if (std::is_signed_v<To> && !std::is_signed_v<From>) {
-        if (from > std::numeric_limits<To>::max()) {
-            return ::android::base::unexpected(::android::BAD_VALUE);
-        }
-    } else {
-        if (from < std::numeric_limits<To>::min() || from > std::numeric_limits<To>::max()) {
-            return ::android::base::unexpected(::android::BAD_VALUE);
-        }
-    }
-    return static_cast<To>(from);
-}
-
-/**
- * A generic template to safely cast between types, that are intended to be the same size, but
- * interpreted differently.
- */
-template<typename To, typename From>
-ConversionResult<To> convertReinterpret(From from) {
-    static_assert(sizeof(From) == sizeof(To));
-    return static_cast<To>(from);
-}
-
-/**
- * A generic template that helps convert containers of convertible types, using iterators.
- */
-template<typename InputIterator, typename OutputIterator, typename Func>
-::android::status_t convertRange(InputIterator start,
-                      InputIterator end,
-                      OutputIterator out,
-                      const Func& itemConversion) {
-    for (InputIterator iter = start; iter != end; ++iter, ++out) {
-        *out = VALUE_OR_RETURN_STATUS(itemConversion(*iter));
-    }
-    return ::android::OK;
-}
-
-/**
- * A generic template that helps convert containers of convertible types, using iterators.
- * Uses a limit as maximum conversion items.
- */
-template<typename InputIterator, typename OutputIterator, typename Func>
-::android::status_t convertRangeWithLimit(InputIterator start,
-                      InputIterator end,
-                      OutputIterator out,
-                      const Func& itemConversion,
-                      const size_t limit) {
-    InputIterator last = end;
-    if (end - start > limit) {
-        last = start + limit;
-    }
-    for (InputIterator iter = start; (iter != last); ++iter, ++out) {
-        *out = VALUE_OR_RETURN_STATUS(itemConversion(*iter));
-    }
-    return ::android::OK;
-}
-
-/**
- * A generic template that helps convert containers of convertible types.
- */
-template<typename OutputContainer, typename InputContainer, typename Func>
-ConversionResult<OutputContainer>
-convertContainer(const InputContainer& input, const Func& itemConversion) {
-    OutputContainer output;
-    auto ins = std::inserter(output, output.begin());
-    for (const auto& item : input) {
-        *ins = VALUE_OR_RETURN(itemConversion(item));
-    }
-    return output;
-}
-
-/**
- * A generic template that helps convert containers of convertible types
- * using an item conversion function with an additional parameter.
- */
-template<typename OutputContainer, typename InputContainer, typename Func, typename Parameter>
-ConversionResult<OutputContainer>
-convertContainer(const InputContainer& input, const Func& itemConversion, const Parameter& param) {
-    OutputContainer output;
-    auto ins = std::inserter(output, output.begin());
-    for (const auto& item : input) {
-        *ins = VALUE_OR_RETURN(itemConversion(item, param));
-    }
-    return output;
-}
-
-/**
- * A generic template that helps to "zip" two input containers of the same size
- * into a single vector of converted types. The conversion function must
- * thus accept two arguments.
- */
-template<typename OutputContainer, typename InputContainer1,
-        typename InputContainer2, typename Func>
-ConversionResult<OutputContainer>
-convertContainers(const InputContainer1& input1, const InputContainer2& input2,
-        const Func& itemConversion) {
-    auto iter2 = input2.begin();
-    OutputContainer output;
-    auto ins = std::inserter(output, output.begin());
-    for (const auto& item1 : input1) {
-        RETURN_IF_ERROR(iter2 != input2.end() ? ::android::OK : ::android::BAD_VALUE);
-        *ins = VALUE_OR_RETURN(itemConversion(item1, *iter2++));
-    }
-    return output;
-}
-
-/**
- * A generic template that helps to "unzip" a per-element conversion into
- * a pair of elements into a pair of containers. The conversion function
- * must emit a pair of elements.
- */
-template<typename OutputContainer1, typename OutputContainer2,
-        typename InputContainer, typename Func>
-ConversionResult<std::pair<OutputContainer1, OutputContainer2>>
-convertContainerSplit(const InputContainer& input, const Func& itemConversion) {
-    OutputContainer1 output1;
-    OutputContainer2 output2;
-    auto ins1 = std::inserter(output1, output1.begin());
-    auto ins2 = std::inserter(output2, output2.begin());
-    for (const auto& item : input) {
-        auto out_pair = VALUE_OR_RETURN(itemConversion(item));
-        *ins1 = out_pair.first;
-        *ins2 = out_pair.second;
-    }
-    return std::make_pair(output1, output2);
-}
-
-////////////////////////////////////////////////////////////////////////////////////////////////////
-// The code below establishes:
-// IntegralTypeOf<T>, which works for either integral types (in which case it evaluates to T), or
-// enum types (in which case it evaluates to std::underlying_type_T<T>).
-
-template<typename T, typename = std::enable_if_t<std::is_integral_v<T> || std::is_enum_v<T>>>
-struct IntegralTypeOfStruct {
-    using Type = T;
-};
-
-template<typename T>
-struct IntegralTypeOfStruct<T, std::enable_if_t<std::is_enum_v<T>>> {
-    using Type = std::underlying_type_t<T>;
-};
-
-template<typename T>
-using IntegralTypeOf = typename IntegralTypeOfStruct<T>::Type;
-
-////////////////////////////////////////////////////////////////////////////////////////////////////
-// Utilities for handling bitmasks.
-
-template<typename Enum>
-Enum indexToEnum_index(int index) {
-    static_assert(std::is_enum_v<Enum> || std::is_integral_v<Enum>);
-    return static_cast<Enum>(index);
-}
-
-template<typename Enum>
-Enum indexToEnum_bitmask(int index) {
-    static_assert(std::is_enum_v<Enum> || std::is_integral_v<Enum>);
-    return static_cast<Enum>(1 << index);
-}
-
-template<typename Mask, typename Enum>
-Mask enumToMask_bitmask(Enum e) {
-    static_assert(std::is_enum_v<Enum> || std::is_integral_v<Enum>);
-    static_assert(std::is_enum_v<Mask> || std::is_integral_v<Mask>);
-    return static_cast<Mask>(e);
-}
-
-template<typename Mask, typename Enum>
-Mask enumToMask_index(Enum e) {
-    static_assert(std::is_enum_v<Enum> || std::is_integral_v<Enum>);
-    static_assert(std::is_enum_v<Mask> || std::is_integral_v<Mask>);
-    return static_cast<Mask>(static_cast<std::make_unsigned_t<IntegralTypeOf<Mask>>>(1)
-            << static_cast<int>(e));
-}
-
-template<typename DestMask, typename SrcMask, typename DestEnum, typename SrcEnum>
-ConversionResult<DestMask> convertBitmask(
-        SrcMask src, const std::function<ConversionResult<DestEnum>(SrcEnum)>& enumConversion,
-        const std::function<SrcEnum(int)>& srcIndexToEnum,
-        const std::function<DestMask(DestEnum)>& destEnumToMask) {
-    using UnsignedDestMask = std::make_unsigned_t<IntegralTypeOf<DestMask>>;
-    using UnsignedSrcMask = std::make_unsigned_t<IntegralTypeOf<SrcMask>>;
-
-    UnsignedDestMask dest = static_cast<UnsignedDestMask>(0);
-    UnsignedSrcMask usrc = static_cast<UnsignedSrcMask>(src);
-
-    int srcBitIndex = 0;
-    while (usrc != 0) {
-        if (usrc & 1) {
-            SrcEnum srcEnum = srcIndexToEnum(srcBitIndex);
-            DestEnum destEnum = VALUE_OR_RETURN(enumConversion(srcEnum));
-            DestMask destMask = destEnumToMask(destEnum);
-            dest |= destMask;
-        }
-        ++srcBitIndex;
-        usrc >>= 1;
-    }
-    return static_cast<DestMask>(dest);
-}
-
-template<typename Mask, typename Enum>
-bool bitmaskIsSet(Mask mask, Enum index) {
-    return (mask & enumToMask_index<Mask, Enum>(index)) != 0;
-}
-
-////////////////////////////////////////////////////////////////////////////////////////////////////
-// Utilities for working with AIDL unions.
-// UNION_GET(obj, fieldname) returns a ConversionResult<T> containing either the strongly-typed
-//   value of the respective field, or ::android::BAD_VALUE if the union is not set to the requested
-//   field.
-// UNION_SET(obj, fieldname, value) sets the requested field to the given value.
-
-template<typename T, typename T::Tag tag>
-using UnionFieldType = std::decay_t<decltype(std::declval<T>().template get<tag>())>;
-
-template<typename T, typename T::Tag tag>
-ConversionResult<UnionFieldType<T, tag>> unionGetField(const T& u) {
-    if (u.getTag() != tag) {
-        return ::android::base::unexpected(::android::BAD_VALUE);
-    }
-    return u.template get<tag>();
-}
-
-#define UNION_GET(u, field) \
-    unionGetField<std::decay_t<decltype(u)>, std::decay_t<decltype(u)>::Tag::field>(u)
-
-#define UNION_SET(u, field, value) \
-    (u).set<std::decay_t<decltype(u)>::Tag::field>(value)
-
-#define UNION_MAKE(u, field, value) u::make<u::Tag::field>(value)
-
-namespace aidl_utils {
-
-/**
- * Return true if the value is valid for the AIDL enumeration.
- */
-template <typename T>
-bool isValidEnum(T value) {
-#if defined(BACKEND_NDK)
-    constexpr ndk::enum_range<T> er{};
-#else
-    constexpr ::android::enum_range<T> er{};
-#endif
-    return std::find(er.begin(), er.end(), value) != er.end();
-}
-
-// T is a "container" of enum binder types with a toString().
-template <typename T>
-std::string enumsToString(const T& t) {
-    std::string s;
-    for (const auto item : t) {
-        if (s.empty()) {
-            s = toString(item);
-        } else {
-            s.append("|").append(toString(item));
-        }
-    }
-    return s;
-}
-
-/**
- * Return the equivalent Android ::android::status_t from a binder exception code.
- *
- * Generally one should use statusTFromBinderStatus() instead.
- *
- * Exception codes can be generated from a remote Java service exception, translate
- * them for use on the Native side.
- *
- * Note: for EX_TRANSACTION_FAILED and EX_SERVICE_SPECIFIC a more detailed error code
- * can be found from transactionError() or serviceSpecificErrorCode().
- */
-static inline ::android::status_t statusTFromExceptionCode(int32_t exceptionCode) {
-    using namespace ::android::binder;
-    switch (exceptionCode) {
-        case Status::EX_NONE:
-            return ::android::OK;
-        case Status::EX_SECURITY:  // Java SecurityException, rethrows locally in Java
-            return ::android::PERMISSION_DENIED;
-        case Status::EX_BAD_PARCELABLE:  // Java BadParcelableException, rethrows in Java
-        case Status::EX_ILLEGAL_ARGUMENT:  // Java IllegalArgumentException, rethrows in Java
-        case Status::EX_NULL_POINTER:  // Java NullPointerException, rethrows in Java
-            return ::android::BAD_VALUE;
-        case Status::EX_ILLEGAL_STATE:  // Java IllegalStateException, rethrows in Java
-        case Status::EX_UNSUPPORTED_OPERATION:  // Java UnsupportedOperationException, rethrows
-            return ::android::INVALID_OPERATION;
-        case Status::EX_HAS_REPLY_HEADER: // Native strictmode violation
-        case Status::EX_PARCELABLE:  // Java bootclass loader (not standard exception), rethrows
-        case Status::EX_NETWORK_MAIN_THREAD:  // Java NetworkOnMainThreadException, rethrows
-        case Status::EX_TRANSACTION_FAILED: // Native - see error code
-        case Status::EX_SERVICE_SPECIFIC:   // Java ServiceSpecificException,
-                                            // rethrows in Java with integer error code
-            return ::android::UNKNOWN_ERROR;
-    }
-    return ::android::UNKNOWN_ERROR;
-}
-
-/**
- * Return the equivalent Android ::android::status_t from a binder status.
- *
- * Used to handle errors from a AIDL method declaration
- *
- * [oneway] void method(type0 param0, ...)
- *
- * or the following (where return_type is not a status_t)
- *
- * return_type method(type0 param0, ...)
- */
-static inline ::android::status_t statusTFromBinderStatus(const ::android::binder::Status &status) {
-    return status.isOk() ? ::android::OK // check ::android::OK,
-        : status.serviceSpecificErrorCode() // service-side error, not standard Java exception
-                                            // (fromServiceSpecificError)
-        ?: status.transactionError() // a native binder transaction error (fromStatusT)
-        ?: statusTFromExceptionCode(status.exceptionCode()); // a service-side error with a
-                                                    // standard Java exception (fromExceptionCode)
-}
-
-#if defined(BACKEND_NDK)
-static inline ::android::status_t statusTFromBinderStatus(const ::ndk::ScopedAStatus &status) {
-    // What we want to do is to 'return statusTFromBinderStatus(status.get()->get())'
-    // However, since the definition of AStatus is not exposed, we have to do the same
-    // via methods of ScopedAStatus:
-    return status.isOk() ? ::android::OK // check ::android::OK,
-        : status.getServiceSpecificError() // service-side error, not standard Java exception
-                                           // (fromServiceSpecificError)
-        ?: status.getStatus() // a native binder transaction error (fromStatusT)
-        ?: statusTFromExceptionCode(status.getExceptionCode()); // a service-side error with a
-                                                     // standard Java exception (fromExceptionCode)
-}
+#if defined(BACKEND_CPP_NDK) || defined(BACKEND_NDK)
+#define BACKEND_NDK_IMPL
+#include <media/AidlConversionUtil-impl.h>
+#undef BACKEND_NDK_IMPL
 #endif
 
-/**
- * Return a binder::Status from native service status.
- *
- * This is used for methods not returning an explicit status_t,
- * where Java callers expect an exception, not an integer return value.
- */
-static inline ::android::binder::Status binderStatusFromStatusT(
-        ::android::status_t status, const char *optionalMessage = nullptr) {
-    const char * const emptyIfNull = optionalMessage == nullptr ? "" : optionalMessage;
-    // From binder::Status instructions:
-    //  Prefer a generic exception code when possible, then a service specific
-    //  code, and finally a ::android::status_t for low level failures or legacy support.
-    //  Exception codes and service specific errors map to nicer exceptions for
-    //  Java clients.
-
-    using namespace ::android::binder;
-    switch (status) {
-        case ::android::OK:
-            return Status::ok();
-        case ::android::PERMISSION_DENIED: // throw SecurityException on Java side
-            return Status::fromExceptionCode(Status::EX_SECURITY, emptyIfNull);
-        case ::android::BAD_VALUE: // throw IllegalArgumentException on Java side
-            return Status::fromExceptionCode(Status::EX_ILLEGAL_ARGUMENT, emptyIfNull);
-        case ::android::INVALID_OPERATION: // throw IllegalStateException on Java side
-            return Status::fromExceptionCode(Status::EX_ILLEGAL_STATE, emptyIfNull);
-    }
-
-    // A service specific error will not show on status.transactionError() so
-    // be sure to use statusTFromBinderStatus() for reliable error handling.
-
-    // throw a ServiceSpecificException.
-    return Status::fromServiceSpecificError(status, emptyIfNull);
-}
-
-} // namespace aidl_utils
-
-}  // namespace android
-
-#if defined(BACKEND_NDK)
-}  // namespace aidl
+#if defined(BACKEND_CPP_NDK) || !defined(BACKEND_NDK)
+#include <media/AidlConversionUtil-impl.h>
 #endif
diff --git a/media/libaudiohal/impl/Android.bp b/media/libaudiohal/impl/Android.bp
index aea31a0..d5f6598 100644
--- a/media/libaudiohal/impl/Android.bp
+++ b/media/libaudiohal/impl/Android.bp
@@ -281,6 +281,7 @@
     ],
     shared_libs: [
         "libbinder_ndk",
+        "libaudio_aidl_conversion_common_cpp",
         "libaudio_aidl_conversion_common_ndk",
         "libaudio_aidl_conversion_effect_ndk",
         "libaudioaidlcommon",
@@ -293,6 +294,6 @@
         "-Wextra",
         "-Werror",
         "-Wthread-safety",
-        "-DBACKEND_NDK",
+        "-DBACKEND_CPP_NDK",
     ],
 }
diff --git a/media/libaudiohal/impl/EffectsFactoryHalAidl.cpp b/media/libaudiohal/impl/EffectsFactoryHalAidl.cpp
index b418b6c..f289f24 100644
--- a/media/libaudiohal/impl/EffectsFactoryHalAidl.cpp
+++ b/media/libaudiohal/impl/EffectsFactoryHalAidl.cpp
@@ -89,7 +89,8 @@
         return BAD_VALUE;
     }
 
-    AudioUuid uuid = VALUE_OR_RETURN_STATUS(legacy2aidl_audio_uuid_t_AudioUuid(*halUuid));
+    AudioUuid uuid = VALUE_OR_RETURN_STATUS(
+            ::aidl::android::legacy2aidl_audio_uuid_t_AudioUuid(*halUuid));
     std::lock_guard lg(mLock);
     return getHalDescriptorWithImplUuid_l(uuid, pDescriptor);
 }
@@ -100,7 +101,8 @@
         return BAD_VALUE;
     }
 
-    AudioUuid type = VALUE_OR_RETURN_STATUS(legacy2aidl_audio_uuid_t_AudioUuid(*halType));
+    AudioUuid type = VALUE_OR_RETURN_STATUS(
+            ::aidl::android::legacy2aidl_audio_uuid_t_AudioUuid(*halType));
     std::lock_guard lg(mLock);
     return getHalDescriptorWithTypeUuid_l(type, descriptors);
 }
@@ -117,7 +119,8 @@
 
     ALOGI("%s session %d ioId %d", __func__, sessionId, ioId);
 
-    AudioUuid aidlUuid = VALUE_OR_RETURN_STATUS(legacy2aidl_audio_uuid_t_AudioUuid(*uuid));
+    AudioUuid aidlUuid = VALUE_OR_RETURN_STATUS(
+            ::aidl::android::legacy2aidl_audio_uuid_t_AudioUuid(*uuid));
     std::shared_ptr<IEffect> aidlEffect;
     Descriptor desc;
     RETURN_STATUS_IF_ERROR(statusTFromBinderStatus(mFactory->createEffect(aidlUuid, &aidlEffect)));
diff --git a/media/libaudiohal/impl/StreamHalAidl.cpp b/media/libaudiohal/impl/StreamHalAidl.cpp
index 1c15cfb..5f62ad8 100644
--- a/media/libaudiohal/impl/StreamHalAidl.cpp
+++ b/media/libaudiohal/impl/StreamHalAidl.cpp
@@ -505,7 +505,8 @@
     // Initialize the offload metadata
     mOffloadMetadata.sampleRate = static_cast<int32_t>(config.sample_rate);
     mOffloadMetadata.channelMask = VALUE_OR_FATAL(
-            legacy2aidl_audio_channel_mask_t_AudioChannelLayout(config.channel_mask, false));
+            ::aidl::android::legacy2aidl_audio_channel_mask_t_AudioChannelLayout(
+                    config.channel_mask, false));
     mOffloadMetadata.averageBitRatePerSecond = static_cast<int32_t>(config.offload_info.bit_rate);
 }
 
@@ -769,8 +770,9 @@
                 return BAD_VALUE;
             }
             mOffloadMetadata.channelMask =
-                    VALUE_OR_RETURN_STATUS(legacy2aidl_audio_channel_mask_t_AudioChannelLayout(
-                        channel_mask, false));
+                    VALUE_OR_RETURN_STATUS(
+                            ::aidl::android::legacy2aidl_audio_channel_mask_t_AudioChannelLayout(
+                                    channel_mask, false));
             parameters.remove(String8(AudioParameter::keyOffloadCodecChannels));
         }