| /* |
| * Copyright (C) 2019 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. |
| */ |
| |
| /* |
| * Definitions and interface related to HAL implementations of Acoustic Echo Canceller (AEC). |
| * |
| * AEC cleans the microphone signal by removing from it audio data corresponding to loudspeaker |
| * playback. Note that this process can be nonlinear. |
| * |
| */ |
| |
| #ifndef _AUDIO_AEC_H_ |
| #define _AUDIO_AEC_H_ |
| |
| #include <stdint.h> |
| #include <pthread.h> |
| #include <sys/time.h> |
| #include <hardware/audio.h> |
| #include <audio_utils/resampler.h> |
| #include "audio_hw.h" |
| #include "fifo_wrapper.h" |
| |
| struct aec_t { |
| pthread_mutex_t lock; |
| size_t num_reference_channels; |
| int32_t *mic_buf; |
| size_t mic_num_channels; |
| size_t mic_buf_size_bytes; |
| size_t mic_frame_size_bytes; |
| uint32_t mic_sampling_rate; |
| struct aec_info last_mic_info; |
| int32_t *spk_buf; |
| size_t spk_num_channels; |
| size_t spk_buf_size_bytes; |
| size_t spk_frame_size_bytes; |
| uint32_t spk_sampling_rate; |
| struct aec_info last_spk_info; |
| int16_t *spk_buf_playback_format; |
| int16_t *spk_buf_resampler_out; |
| void *spk_fifo; |
| void *ts_fifo; |
| ssize_t read_write_diff_bytes; |
| struct resampler_itfe *spk_resampler; |
| bool spk_running; |
| bool prev_spk_running; |
| }; |
| |
| #ifdef AEC_HAL |
| |
| /* Write audio samples to AEC reference FIFO for use in AEC. |
| * Both audio samples and timestamps are added in FIFO fashion. |
| * Must be called after every write to PCM. */ |
| int write_to_reference_fifo (struct aec_t *aec, void *buffer, struct aec_info *info); |
| |
| /* Processing function call for AEC. |
| * AEC output is updated at location pointed to by 'buffer'. |
| * This function does not run AEC when there is no playback - |
| * as communicated to this AEC interface using aec_set_spk_running().*/ |
| int process_aec (struct aec_t *aec, void* buffer, struct aec_info *info); |
| |
| /* Initialize AEC object. |
| * This must be called when the audio device is opened. |
| * ALSA device mutex must be held before calling this API.*/ |
| int init_aec (int sampling_rate, int num_reference_channels, |
| int num_microphone_channels, struct aec_t **); |
| |
| /* Release AEC object. |
| * This must be called when the audio device is closed. */ |
| void release_aec(struct aec_t *aec); |
| |
| /* Initialize reference configuration for AEC. |
| * Must be called when a new output stream is opened. */ |
| int init_aec_reference_config (struct aec_t *aec, struct alsa_stream_out *out); |
| |
| /* Initialize microphone configuration for AEC. |
| * Must be called when a new input stream is opened. */ |
| int init_aec_mic_config (struct aec_t *aec, struct alsa_stream_in *in); |
| |
| /* Clear reference configuration for AEC. |
| * Must be called when the output stream is closed. */ |
| void destroy_aec_reference_config (struct aec_t *aec); |
| |
| /* Clear microphone configuration for AEC. |
| * Must be called when the input stream is closed. */ |
| void destroy_aec_mic_config (struct aec_t *aec); |
| |
| /* Used to communicate playback state (running or not) to AEC interface. |
| * This is used by process_aec() to determine if AEC processing is to be run. */ |
| void aec_set_spk_running (struct aec_t *aec, bool state); |
| |
| #else /* #ifdef AEC_HAL */ |
| |
| #define write_to_reference_fifo(...) ((int)0) |
| #define process_aec(...) ((int)0) |
| #define init_aec(...) ((int)0) |
| #define release_aec(...) ((void)0) |
| #define init_aec_reference_config(...) ((int)0) |
| #define init_aec_mic_config(...) ((int)0) |
| #define destroy_aec_reference_config(...) ((void)0) |
| #define destroy_aec_mic_config(...) ((void)0) |
| #define aec_set_spk_running(...) ((void)0) |
| |
| #endif /* #ifdef AEC_HAL */ |
| |
| #endif /* _AUDIO_AEC_H_ */ |