Google Time Lapse Recording 在高档手机上的一个实现
实现的配置是 mCaptureFp=240 mFrameRate=30
设置的SampleRate=48K，计算得到的sampleRate为384K
1047 if (mCaptureFpsEnable && mCaptureFps >= mFrameRate) {
1048 // Upscale the sample rate for slow motion recording.
1049 // Fail audio source creation if source sample rate is too high, as it could
1050 // cause out-of-memory due to large input buffer size. And audio recording
1051 // probably doesn't make sense in the scenario, since the slow-down factor
1052 // is probably huge (eg. mSampleRate=48K, mCaptureFps=240, mFrameRate=1).
1053 const static int32_t SAMPLE_RATE_HZ_MAX = 192000;
1054 sourceSampleRate =
1055 (mSampleRate * mCaptureFps + mFrameRate / 2) / mFrameRate;
1056 if (sourceSampleRate < mSampleRate || sourceSampleRate > SAMPLE_RATE_HZ_MAX) {
1057 ALOGE("source sample rate out of range! "
1058 "(mSampleRate %d, mCaptureFps %.2f, mFrameRate %d",
1059 mSampleRate, mCaptureFps, mFrameRate);
1060 return NULL;
1061 }
1062 }
1064 sp<AudioSource> audioSource = 1065 new AudioSource( 1066 mAudioSource, 1067 mOpPackageName, 1068 sourceSampleRate,//AudioRecord使用这个值来设置采样率 1069 mAudioChannels, 1070 mSampleRate, 1071 mClientUid, 1072 mClientPid);
如果需要有Pause/Resume功能的话，这里代码可能需要修改
1954 // 30 ms buffer to avoid timestamp overlap
1955 mTotalPausedDurationUs += resumeStartTimeUs - mPauseStartTimeUs - 30000;
1956 }
1957 double timeOffset = -mTotalPausedDurationUs;
1958 if (mCaptureFpsEnable) {
1959 timeOffset *= mCaptureFps / mFrameRate;
1960 }
[测试中出现的问题]
在240FPS的Video状态下，系统忙（CPU占用90%以上）
导致：Audio PCM数据在编码前的queue中堆积
可以查看的方法如下：
121void MediaCodecSource::Puller::Queue::pushBuffer(MediaBuffer *mbuf) {push buffer
122 mReadBuffers.push_back(mbuf);
123}
124
125bool MediaCodecSource::Puller::Queue::readBuffer(MediaBuffer **mbuf) {pop buffer
126 if (mReadBuffers.empty()) {
127 *mbuf = NULL;
128 return false;
129 }
130 *mbuf = *mReadBuffers.begin();
131 mReadBuffers.erase(mReadBuffers.begin());
132 return true;
133}
134
135void MediaCodecSource::Puller::Queue::flush() {清空buffer
136 MediaBuffer *mbuf;
需要在这里打印 mReadBuffers.size()，就知道audio Encoder性能不够
137 while (readBuffer(&mbuf)) {
138 // there are no null buffers in the queue
139 mbuf->release();
140 }
141}
Google Time Lapse Recording 在高档手机上的一个实现
实现的配置是 mCaptureFp=240 mFrameRate=30
设置的SampleRate=48K，计算得到的sampleRate为384K
1047 if (mCaptureFpsEnable && mCaptureFps >= mFrameRate) {
1048 // Upscale the sample rate for slow motion recording.
1049 // Fail audio source creation if source sample rate is too high, as it could
1050 // cause out-of-memory due to large input buffer size. And audio recording
1051 // probably doesn't make sense in the scenario, since the slow-down factor
1052 // is probably huge (eg. mSampleRate=48K, mCaptureFps=240, mFrameRate=1).
1053 const static int32_t SAMPLE_RATE_HZ_MAX = 192000;
1054 sourceSampleRate =
1055 (mSampleRate * mCaptureFps + mFrameRate / 2) / mFrameRate;
1056 if (sourceSampleRate < mSampleRate || sourceSampleRate > SAMPLE_RATE_HZ_MAX) {
1057 ALOGE("source sample rate out of range! "
1058 "(mSampleRate %d, mCaptureFps %.2f, mFrameRate %d",
1059 mSampleRate, mCaptureFps, mFrameRate);
1060 return NULL;
1061 }
1062 }
1064 sp<AudioSource> audioSource = 1065 new AudioSource( 1066 mAudioSource, 1067 mOpPackageName, 1068 sourceSampleRate,//AudioRecord使用这个值来设置采样率 1069 mAudioChannels, 1070 mSampleRate, 1071 mClientUid, 1072 mClientPid);
如果需要有Pause/Resume功能的话，这里代码可能需要修改
1954 // 30 ms buffer to avoid timestamp overlap
1955 mTotalPausedDurationUs += resumeStartTimeUs - mPauseStartTimeUs - 30000;
1956 }
1957 double timeOffset = -mTotalPausedDurationUs;
1958 if (mCaptureFpsEnable) {
1959 timeOffset *= mCaptureFps / mFrameRate;
1960 }
[测试中出现的问题]
在240FPS的Video状态下，系统忙（CPU占用90%以上）
导致：Audio PCM数据在编码前的queue中堆积
可以查看的方法如下：
121void MediaCodecSource::Puller::Queue::pushBuffer(MediaBuffer *mbuf) {push buffer
122 mReadBuffers.push_back(mbuf);
123}
124
125bool MediaCodecSource::Puller::Queue::readBuffer(MediaBuffer **mbuf) {pop buffer
126 if (mReadBuffers.empty()) {
127 *mbuf = NULL;
128 return false;
129 }
130 *mbuf = *mReadBuffers.begin();
131 mReadBuffers.erase(mReadBuffers.begin());
132 return true;
133}
134
135void MediaCodecSource::Puller::Queue::flush() {清空buffer
136 MediaBuffer *mbuf;
需要在这里打印 mReadBuffers.size()，就知道audio Encoder性能不够
137 while (readBuffer(&mbuf)) {
138 // there are no null buffers in the queue
139 mbuf->release();
140 }
141}