问题描述：客户定制的开机动画是带有开机铃声的，但发现用system/media/bootanimation.ts和/oem/media/bootanimation.zip（包含了audio.wav）的方式都试过，开机(视频)动画没问题，但开机铃声会延迟一两秒。

logcat分析：

D BootAnimation found audio.wav, creating playback engine

04-04 185737.155 371 383 D BootAnimation BootAnimationShownTiming start time 5115ms

04-04 185737.155 371 383 D BootAnimation playing clip for part0, size=2642254

04-04 185737.156 371 395 E libOpenSLES CEngine_Realize binding to audio service failed, service up

04-04 185737.158 371 395 D PlayerBasePlayerBase()

04-04 185737.158 371 395 E PlayerBase() binding to audio service f

看开机的logcat，个人理解是播放audio.wav这段音频铃声的时候，audio service服务还没有初始化成功，一直在等待，导致会延迟一点播放。

最终参考了一位网友的文章，顺利解决此问题。修改如下：

frameworks/av/

diff --git a/media/libmediaplayerservice/MediaPlayerService.cpp b/media/libmediaplayerservice/MediaPlayerService.cpp

index bb17943..a1652c2 100755

--- a/media/libmediaplayerservice/MediaPlayerService.cpp

+++ b/media/libmediaplayerservice/MediaPlayerService.cpp

@@ -2622,7 +2622,7 @@ MediaPlayerService::BatteryTracker::BatteryTracker() {

// reset battery stats

// if the mediaserver has crashed, battery stats could be left

// in bad state, reset the state upon service start.

- BatteryNotifier::getInstance().noteResetVideo();

+ // BatteryNotifier::getInstance().noteResetVideo();

}

void MediaPlayerService::BatteryTracker::addBatteryData(uint32_t params)

diff --git a/services/audioflinger/AudioFlinger.cpp b/services/audioflinger/AudioFlinger.cpp

old mode 100644

new mode 100755

index ff5f745..b02e74a

--- a/services/audioflinger/AudioFlinger.cpp

+++ b/services/audioflinger/AudioFlinger.cpp

@@ -156,7 +156,7 @@ AudioFlinger::AudioFlinger()

mIsLowRamDevice(true),

mIsDeviceTypeKnown(false),

mGlobalEffectEnableTime(0),

- mSystemReady(false)

+ mSystemReady(true)

{

// unsigned instead of audio_unique_id_use_t, because ++ operator is unavailable for enum

for (unsigned use = AUDIO_UNIQUE_ID_USE_UNSPECIFIED; use < AUDIO_UNIQUE_ID_USE_MAX; use++) {

diff --git a/services/audioflinger/Threads.cpp b/services/audioflinger/Threads.cpp

old mode 100644

new mode 100755

index a30c460..fb536d6

--- a/services/audioflinger/Threads.cpp

+++ b/services/audioflinger/Threads.cpp

@@ -576,11 +576,11 @@ status_t AudioFlinger::ThreadBase::sendConfigEvent_l(sp& event)

{

status_t status = NO_ERROR;

- if (event->mRequiresSystemReady && !mSystemReady) {

+/* if (event->mRequiresSystemReady && !mSystemReady) {

event->mWaitStatus = false;

mPendingConfigEvents.add(event);

return status;

- }

+ }*/

mConfigEvents.add(event);

ALOGV("sendConfigEvent_l() num events %zu event %d", mConfigEvents.size(), event->mType);

mWaitWorkCV.signal();

@@ -934,7 +934,7 @@ void AudioFlinger::ThreadBase::releaseWakeLock_l()

}

void AudioFlinger::ThreadBase::getPowerManager_l() {

- if (mSystemReady && mPowerManager == 0) {

+ if (mPowerManager == 0) {

// use checkService() to avoid blocking if power service is not up yet

sp binder =

defaultServiceManager()->checkService(String16("power"));

@@ -2642,6 +2642,9 @@ ssize_t AudioFlinger::PlaybackThread::threadLoop_write()

ssize_t bytesWritten;

const size_t offset = mCurrentWriteLength - mBytesRemaining;

+ if (mPowerManager == 0)

+ acquireWakeLock();

+

// If an NBAIO sink is present, use it to write the normal mixer's submix

if (mNormalSink != 0) {

初次开机无开机铃声：

frameworks/av/services/audioflinger/Threads.cpp

@@ -4383,6 +4383,15 @@ AudioFlinger::PlaybackThread::mixer_state AudioFlinger::MixerThread::prepareTrac

track->mHasVolumeController = false;

}

+ /*wmc modify start */

+ char mvalue[PROPERTY_VALUE_MAX] = { 1 };

+ property_get("service.bootanim.exit", mvalue, "");

+ if (strcmp(mvalue,"0") == 0){

+ vlf = 0.25f;

+ vrf = 0.25f;

+ }

+ /*wmc modify end */

+

// For dedicated VoIP outputs, let the HAL apply the stream volume. Track volume is

// still applied by the mixer.

if ((mOutput->flags & AUDIO_OUTPUT_FLAG_VOIP_RX) != 0) {

参考：https://blog.csdn.net/m1126125223/article/details/100656625

https://blog.csdn.net/wangjicong_215/article/details/112251199