| /* |
| ** Copyright 2011, 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 ANDROID_ECHO_REFERENCE_H |
| #define ANDROID_ECHO_REFERENCE_H |
| |
| #include <stdint.h> |
| #include <sys/time.h> |
| |
| __BEGIN_DECLS |
| |
| /* Buffer descriptor used by read() and write() methods, including the time stamp and delay. */ |
| struct echo_reference_buffer { |
| void *raw; // pointer to audio frame |
| size_t frame_count; // number of frames in buffer |
| int32_t delay_ns; // delay for this buffer (see comment below) |
| struct timespec time_stamp; // time stamp for this buffer (see comment below) |
| // default ALSA gettimeofday() format |
| }; |
| /** |
| * + as input: |
| * - delay_ns is the delay introduced by playback buffers |
| * - time_stamp is the time stamp corresponding to the delay calculation |
| * + as output: |
| * unused |
| * when used for EchoReference::read(): |
| * + as input: |
| * - delay_ns is the delay introduced by capture buffers |
| * - time_stamp is the time stamp corresponding to the delay calculation |
| * + as output: |
| * - delay_ns is the delay between the returned frames and the capture time derived from |
| * delay and time stamp indicated as input. This delay is to be communicated to the AEC. |
| * - frame_count is updated with the actual number of frames returned |
| */ |
| |
| struct echo_reference_itfe { |
| int (*read)(struct echo_reference_itfe *echo_reference, struct echo_reference_buffer *buffer); |
| int (*write)(struct echo_reference_itfe *echo_reference, struct echo_reference_buffer *buffer); |
| }; |
| |
| int create_echo_reference(audio_format_t rdFormat, |
| uint32_t rdChannelCount, |
| uint32_t rdSamplingRate, |
| audio_format_t wrFormat, |
| uint32_t wrChannelCount, |
| uint32_t wrSamplingRate, |
| struct echo_reference_itfe **); |
| |
| void release_echo_reference(struct echo_reference_itfe *echo_reference); |
| |
| __END_DECLS |
| |
| #endif // ANDROID_ECHO_REFERENCE_H |