AVCodecSample

video-codec-sample/entry/src/main/          
├── cpp                                # Native层
│   ├── capbilities                    # 能力接口和实现
│   │   ├── include                    # 能力接口
│   │   ├── audio_decoder.cpp          # 音频解码实现
│   │   ├── demuxer.cpp                # 解封装实现
│   │   ├── muxer.cpp                  # 封装实现
│   │   ├── video_decoder.cpp          # 视频解码实现
│   │   └── video_encoder.cpp          # 视频编码实现
│   ├── common                         # 公共模块
│   │   ├── dfx                        # 日志
│   │   ├── sample_callback.cpp        # 编解码回调实现   
│   │   ├── sample_callback.h          # 编解码回调定义
│   │   └── sample_info.h              # 功能实现公共类  
│   ├── render                         # 送显模块接口和实现
│   │   ├── include                    # 送显模块接口
│   │   ├── egl_core.cpp               # 送显参数设置
│   │   ├── plugin_manager.cpp         # 送显模块管理实现
│   │   └── plugin_render.cpp          # 送显逻辑实现
│   ├── sample                         # Native层
│   │   ├── player                     # Native层播放接口和实现
│   │   │   ├── Player.cpp             # Native层播放功能调用逻辑的实现
│   │   │   ├── Player.h               # Native层播放功能调用逻辑的接口
│   │   │   ├── PlayerNative.cpp       # Native层 播放的入口
│   │   │   └── PlayerNative.h         # 
│   │   └── recorder                   # Native层录制接口和实现
│   │       ├── Recorder.cpp           # Native层录制功能调用逻辑的实现
│   │       ├── Recorder.h             # Native层录制功能调用逻辑的接口
│   │       ├── RecorderNative.cpp     # Native层 录制的入口
│   │       └── RecorderNative.h       # 
│   ├── types                          # Native层暴露上来的接口
│   │   ├── libplayer                  # 播放模块暴露给UI层的接口
│   │   └── librecorder                # 录制模块暴露给UI层的接口
│   └── CMakeLists.txt                 # 编译入口       
├── ets                                # UI层
│   ├── common                         # 公共模块
│   │   └──utils                       # 共用的工具类
│   │       ├── CameraCheck.ets        # 相机能力查询
│   │       ├── DateTimeUtils.ets      # 获取当前时间
│   │       └── Logger.ts              # 日志工具
│   ├── CommonConstants.ets            # 参数常量
│   ├── entryability                   # 应用的入口
│   │   └── EntryAbility.ts            # 申请权限弹窗实现
│   ├── pages                          # EntryAbility 包含的页面
│   │   └── Index.ets                  # 首页/播放页面
│   └── sample                         # sample
│       └── recorder                   # 录制
│           └── Recorder.ets           # 录制页面
├── resources                          # 用于存放应用所用到的资源文件
│   ├── base                           # 该目录下的资源文件会被赋予唯一的ID
│   │   ├── element                    # 用于存放字体和颜色 
│   │   ├── media                      # 用于存放图片
│   │   └── profile                    # 应用入口首页
│   ├── en_US                          # 设备语言是美式英文时，优先匹配此目录下资源
│   └── zh_CN                          # 设备语言是简体中文时，优先匹配此目录下资源
└── module.json5                       # 模块配置信息

/*
 * Query the the time at which a particular frame was presented.
 *
 * @since 10
 *
 * @param renderer Reference created by OH_AudioStreamBuilder_GenerateRenderer()
 * @param clockId {@link #CLOCK_MONOTONIC}
 * @param framePosition Pointer to a variable to receive the position
 * @param timestamp Pointer to a variable to receive the timestamp
 * @return Function result code:
 *         {@link AUDIOSTREAM_SUCCESS} If the execution is successful.
 *         {@link AUDIOSTREAM_ERROR_INVALID_PARAM}:
 *                                                 1.The param of renderer is nullptr;
 *                                                 2.The param of clockId invalid.
 *         {@link AUDIOSTREAM_ERROR_ILLEGAL_STATE} Execution status exception.
 */
OH_AudioStream_Result OH_AudioRenderer_GetTimestamp(OH_AudioRenderer* renderer,
    clockid_t clockId, int64_t* framePosition, int64_t* timestamp);

// get audio render position
int64_t framePosition = 0;
int64_t timestamp = 0;
int32_t ret = OH_AudioRenderer_GetTimestamp(audioRenderer_, CLOCK_MONOTONIC, &framePosition, &timestamp);
AVCODEC_SAMPLE_LOGI("VD framePosition: %{public}li, nowTimeStamp: %{public}li", framePosition, nowTimeStamp);
audioTimeStamp = timestamp; // ns

// audio render getTimeStamp error, render it
if (ret != AUDIOSTREAM_SUCCESS || (timestamp == 0) || (framePosition == 0)) {
    // first frame, render without wait
    videoDecoder_->FreeOutputBuffer(bufferInfo.bufferIndex, true);
    lastPushTime = std::chrono::system_clock::now();
    continue;
}

// after seek, audio render flush, framePosition = 0, then writtenSampleCnt = 0
int64_t latency = (writtenSampleCnt - framePosition) * 1000 * 1000 / sampleInfo_.audioSampleRate;
AVCODEC_SAMPLE_LOGI("VD latency: %{public}li writtenSampleCnt: %{public}li", latency, writtenSampleCnt);

nowTimeStamp = GetCurrentTime();
int64_t anchordiff = (nowTimeStamp - audioTimeStamp) / 1000;

int64_t audioPlayedTime = audioBufferPts - latency + anchordiff; // us, audio buffer accelerate render time
int64_t videoPlayedTime = bufferInfo.attr.pts;                   // us, video buffer expected render time

// audio render timestamp and now timestamp diff
int64_t waitTimeUs = videoPlayedTime - audioPlayedTime; // us

// video buffer is too late, drop it
if (waitTimeUs < WAIT_TIME_US_THRESHOLD_WARNING) {
    dropFrame = true;
    AVCODEC_SAMPLE_LOGI("VD buffer is too late");
} else {
    AVCODEC_SAMPLE_LOGE("VD buffer is too early waitTimeUs:%{public}ld", waitTimeUs);
    // [0, ), render it wait waitTimeUs, max 1s
    // [-40, 0), render it
    if (waitTimeUs > WAIT_TIME_US_THRESHOLD) {
        waitTimeUs = WAIT_TIME_US_THRESHOLD;
    }
    // per frame render time reduced by 33ms
    if (waitTimeUs > sampleInfo_.frameInterval + PER_SINK_TIME_THRESHOLD) {
        waitTimeUs = sampleInfo_.frameInterval + PER_SINK_TIME_THRESHOLD;
        AVCODEC_SAMPLE_LOGE("VD buffer is too early and reduced 33ms, waitTimeUs: %{public}ld", waitTimeUs);
    }    
}

if (static_cast<double>(waitTimeUs) > FRAME_TIME * LIP_SYNC_BALANCE_VALUE) {
    std::this_thread::sleep_for(std::chrono::microseconds(
        static_cast<int64_t>(static_cast<double>(waitTimeUs)-FRAME_TIME * LIP_SYNC_BALANCE_VALUE)));
}
ret = videoDecoder_->FreeOutputBuffer(bufferInfo.bufferIndex, !dropFrame, FRAME_TIME * LIP_SYNC_BALANCE_VALUE * 1000 + GetCurrentTime());
CHECK_AND_BREAK_LOG(ret == AVCODEC_SAMPLE_ERR_OK, "Decoder output thread");