mediarecorder

android_media_MediaRecorder.cpp

MediaRecorder.cpp

class MediaRecorder : public BnMediaRecorderClient, public virtual IMediaDeathNotifier

接口文件

ImediaRecorder.cpp

Binder文件

mediaRecorderClient.cpp

class MediaRecorderClient : public BnMediaRecorder

mRecorder = AVMediaServiceFactory::get()->createStagefrightRecorder(opPackageName);

        = new StagefrightRecorder(opPackageName);

StagefrightRecorder.cpp

以MPEG4为例子：

sp<MediaWriter> mWriter：MPEG4Writer::MPEG4Writer(int fd)，其中fd是输出文件。

writer->addSource(encoder);

writer->addSource(audioEncoder);

源的创建:

setupMediaSource(&mediaSource);

=> setupCameraSource(&cameraSource);

=>

    if (mCaptureFpsEnable && mCaptureFps != mFrameRate ) {

        if (!(mCaptureFps > 0.)) {

            ALOGE("Invalid mCaptureFps value: %lf", mCaptureFps);

            return BAD_VALUE;

        }

        mCameraSourceTimeLapse = AVFactory::get()->CreateCameraSourceTimeLapseFromCamera(

                mCamera, mCameraProxy, mCameraId, mClientName, mClientUid, mClientPid,

                videoSize, mFrameRate, mPreviewSurface,

                std::llround(1e6 / mCaptureFps));

        *cameraSource = mCameraSourceTimeLapse;

    } else {

        *cameraSource = AVFactory::get()->CreateCameraSourceFromCamera(

                mCamera, mCameraProxy, mCameraId, mClientName, mClientUid, mClientPid,

                videoSize, mFrameRate,

                mPreviewSurface);

}

=>

  return CameraSource::CreateFromCamera(camera, proxy, cameraId,

            clientName, clientUid, clientPid, videoSize, frameRate, surface,

            storeMetaDataInVideoBuffers);

=> CameraSource *source = new CameraSource(camera, proxy, cameraId,

            clientName, clientUid, clientPid, videoSize, frameRate, surface,

            storeMetaDataInVideoBuffers);

sp<MediaCodecSource> encoder = MediaCodecSource::Create(

            mLooper, format, cameraSource, mPersistentSurface, flags);

mGraphicBufferProducer = encoder->getGraphicBufferProducer();

mVideoEncoderSource = encoder;

camera模块回调到mediarecoreder模块：

void CameraSource::recordingFrameHandleCallbackTimestamp(int64_t timestampUs,

                native_handle_t* handle)

{

         mFramesReceived.push_back(data);//数据保存到mFramesReceived

         mFrameAvailableCondition.signal();

}

status_t CameraSource::read(

        MediaBuffer **buffer, const ReadOptions *options) {

         mFramesBeingEncoded.push_back(frame);

         *buffer = new MediaBuffer(frame->pointer(), frame->size());

}

Read函数的调用，

首先MPEG4Writer.cpp的status_t MediaCodecSource::Puller::start(const sp<MetaData> &meta, const sp<AMessage> &notify)

{

         sp<AMessage> msg = new AMessage(kWhatStart, this);

}

然后：

case kWhatStart:

{

         mSource->start(static_cast<MetaData *>(obj.get()));

         schedulePull();

}

void MediaCodecSource::Puller::schedulePull() {

    (new AMessage(kWhatPull, this))->post();

}

然后处理

case kWhatPull:

{

         mSource->read(&mbuf); //这个就是camerasource 的read

         queue->pushBuffer(mbuf);

         mNotify->post();//mPuller->start(meta.get(), notify);   kWhatPullerNotify

msg->post();//循环跑到case kWhatPull:

}

然后在MediaCodecSource处理

case kWhatPullerNotify:

{

         feedEncoderInputBuffers();

}

status_t MediaCodecSource::feedEncoderInputBuffers()

{

         mPuller->readBuffer(&mbuf);

         status_t err = mEncoder->getInputBuffer(bufferIndex, &inbuf);

         memcpy(inbuf->data(), mbuf->data(), size);

         inbuf->setMediaBufferBase(mbuf);

         status_t err = mEncoder->queueInputBuffer(

                bufferIndex, 0, size, timeUs, flags);

}

status_t MediaCodec::getInputBuffer(size_t index, sp<MediaCodecBuffer> *buffer) {

         std::vector<BufferInfo> &buffers = mPortBuffers[kPortIndexInput];

         const BufferInfo &info = buffers[index];

         *buffer = info.mData;

}

status_t MediaCodec::queueInputBuffer(

        size_t index,

        size_t offset,

        size_t size,

        int64_t presentationTimeUs,

        uint32_t flags,

        AString *errorDetailMsg) {

}

case kWhatQueueInputBuffer:

{

         status_t err = onQueueInputBuffer(msg);

}

status_t MediaCodec::onQueueInputBuffer(const sp<AMessage> &msg) {

         err = mBufferChannel->queueInputBuffer(buffer);

}