音频

open

outputDesc-mLatency

mediaplayer.cpp

Media FMAPP

MediaCodec.cpp

Audio Framework(frameworks/av/services/audioflinger/)

openOutputStream

ioConfigChanged

get_channels

Media PlayerAPP

openOutput

IAudioFlingerClient.cpp

android_media_AudioTrack.cpp

AudioStreamOut.cpp

android_media_MediaCodec.cpp

AudioPolicyManager.cpp

IAudioFlinger.cpp

ServerProxy

desc-mPatch = mPatch;desc-mChannelMask = mChannelMask;desc-mSamplingRate = mSampleRate;desc-mFormat = mFormat;desc-mFrameCount = mNormalFrameCount;desc-mLatency = latency_l();

open_output_stream

android_hardware_Radio.cpp

AudioPolicyClientImpl.cpp

Threads.cpp

getChannelMask

AudioMixer.cpp

AudioHwDevice.cpp

android.media.AudioSystem

MixerThread

getTimestamp

Audio Framework(frameworks/av/services/audiopolicy/)

Media JNI(frameworks/base/media/jni/)

releaseBuffer

get_sample_rate

android_media_AmrInputStream.cpp

getSampleRate

outputDesc-mSamplingRate

setDeviceConnectionStateInt

AudioTrack

AudioTrackShared.cpp

Engine.cpp

android_media_MediaPlayer.cpp

IMediaPlayer.cpp

audio_track_cblk_t* cblk = mCblk;front = android_atomic_acquire_load(&cblk-u.mStreaming.mFront);rear = cblk-u.mStreaming.mRear;buffer-mRaw = part1 0 ? &((char *) mBuffers)[(mIsOut ? rear : front) * mFrameSize] : NULL;

if (mLatchDValid) { mLatchQ = mLatchD; mLatchDValid = false; mLatchQValid = true;}

ClientProxy

AudioTrack.cpp

IAudioRecord.cpp

obtainBuffer

android.media.MediaPlayer

getSamplingRate

mEpoch + mCblk-mServer;

getLatency

MultiMedia Service(frameworks/av/media/libmediaplayerservice/)

get_buffer_size

ACodec.cpp

MediaExtractor.cpp

get_presentation_position

openOutput_l

AudioPolicyManager

AudioSystem.cpp

getMinBufferSize

AudioTrackClientProxy

getFrameSize

android.media.MediaRecorder

native_setup

getOutputSamplingRate

Media Part

get_latency

threadLoop_write

AudioTrackShared.h

createTrack

Tracks.cpp

getFormat

android.media.AmrInputStream

get_format

mLatency

Track

TrackHandle

t.in = t.buffer.raw;

AudioTrack.java

mCblkMemory = client-heap()-allocate(size);mCblk = static_cast(mCblkMemory-pointer())new(mCblk) audio_track_cblk_t();mBuffer = (char*)mCblk + sizeof(audio_track_cblk_t);

android.media.AudioRecord

android.media.AudioManager

audio_hw.cpp

mLatchDValid = false; status_t status = mNormalSink-getTimestamp(mLatchD.mTimestamp); if (status == NO_ERROR) { size_t totalFramesWritten = mNormalSink-framesWritten(); if (totalFramesWritten = mLatchD.mTimestamp.mPosition) { mLatchD.mUnpresentedFrames = totalFramesWritten - mLatchD.mTimestamp.mPosition; // mLatchD.mFramesReleased is set immediately before D is clocked into Q mLatchDValid = true; } }

Phone CallAPP

AudioStreamInSource.cpp

IMediaPlayerService.cpp

getMinFrameCount

threadLoop

outputDesc-mFrameCount

readOutputParameters_l

AudioTrackServerProxy

latency

IMediaRecorder.cpp

convertMixerFormat

SoftOMXPlugin.cpp

mLatency = mAfLatency + (1000*frameCount) / mSampleRate;mFrameCount = frameCount;if (frameCount mReqFrameCount) { mReqFrameCount = frameCount;}

MultiMedia

AudioStreamOutSink.cpp

IAudioTrack.cpp

native_get_latency

Audio Framework(frameworks/av/media/libnbaio/)

SoftOMXComponent.cpp

PlaybackThread

getNextBuffer

android_media_MediaRecorder.cpp

uint32_t sampleRate = mAudioTrackServerProxy-getSampleRate();AudioPlaybackRate playbackRate = mAudioTrackServerProxy-getPlaybackRate();uint32_t unpresentedFrames = ((double) playbackThread-mLatchQ.mUnpresentedFrames * sampleRate * playbackRate.mSpeed)/ playbackThread-mSampleRate;ssize_t i = playbackThread-mLatchQ.mFramesReleased.indexOfKey(this);uint32_t framesWritten = i = 0 ? playbackThread-mLatchQ.mFramesReleased[i] : mAudioTrackServerProxy-framesReleased(); if (framesWritten = unpresentedFrames) { timestamp.mPosition = framesWritten - unpresentedFrames; timestamp.mTime = playbackThread-mLatchQ.mTimestamp.mTime; result = NO_ERROR; }

getFrameCount

Application Part

getPosition

createTrack_l

android_media_AudioRecord.cpp

AudioFlinger.cpp

set

getOutputForAttr

PlaybackThread::Track

Binder IPC

const sp t = mActiveTracks[i].promote();Track* const track = t.get();

updateAndGetPosition_l

TrackBase

setParameter

getOutputFrameCount

omx

nuplayer

out_write

out = reinterpret_cast((uint8_t*)out + BLOCKSIZE * t1.mMixerChannelCount * audio_bytes_per_sample(t1.mMixerFormat));

android_media_MediaExtractor.cpp

mediarecorder.cpp

write

MediaPlayerService.cpp

AudioRecord.cpp

prepareTracks_l

mReqFrameCount = frameCount;

frameCount * channelCount * bytesPerSample

OMXClient.cpp

android_media_AudioSystem.cpp

Audio JNI(frameworks/base/core/jni/)

AudioTrack.h

Media RecordAPP

native_get_min_buff_size

android.media.AudioTrack

Application Framework(frameworks/base/media/java/android/media)

native_get_timestamp

buffer-mRaw = NULL;

calculateMinFrameCount

track.mainBuffer = valueBuf;

sp iMem = track-getCblk();void *iMemPointer = iMem-pointer();audio_track_cblk_t* cblk = static_cast(iMemPointer);buffers = cblk + 1;

process__genericNoResampling

AudioPolicyService.cpp

Audio/Media Framework(frameworks/av/media/libmedia/)

audio_a2dp_hw.c

OMX Integration Layer

setBufferProvider

StageFright Engine(frameworks/av/media/libstagefright/)

IAudioPolicyService.cpp

MultiMedia Framework

Audio

Audio Part

ExtendedAudioBufferProvider

checkOutputsForDevice

getOutputLatency

AudioBufferProvider

track__NoResample

int32_t *out = t1.mainBuffer;

MediaRecorderClient.cpp