android wifidisplay生成I 帧的相关代码

wifidisplayframeworksavmedialibstagefrightwifi-displaysourceConverter.cpp

 

status_t Converter::initEncoder() {
    AString inputMIME;
    CHECK(mInputFormat->findString("mime", &inputMIME));

    AString outputMIME;
    bool isAudio = false;
    if (!strcasecmp(inputMIME.c_str(), MEDIA_MIMETYPE_AUDIO_RAW)) {
        if (mIsPCMAudio) {
            outputMIME = MEDIA_MIMETYPE_AUDIO_RAW;
        } else {
            outputMIME = MEDIA_MIMETYPE_AUDIO_AAC;
        }
        isAudio = true;
    } else if (!strcasecmp(inputMIME.c_str(), MEDIA_MIMETYPE_VIDEO_RAW)) {
        outputMIME = MEDIA_MIMETYPE_VIDEO_AVC;
    } else {
        TRESPASS();
    }

    if (!mIsPCMAudio) {
        mEncoder = MediaCodec::CreateByType(
                mCodecLooper, outputMIME.c_str(), true /* encoder */);

        if (mEncoder == NULL) {
            return ERROR_UNSUPPORTED;
        }
    }

    mOutputFormat = mInputFormat->dup();

    if (mIsPCMAudio) {
        return OK;
    }

    mOutputFormat->setString("mime", outputMIME.c_str());

    int32_t audioBitrate = getBitrate("media.wfd.audio-bitrate", 128000);
    int32_t videoBitrate = getBitrate("media.wfd.video-bitrate", 2* 1024 * 1024);

    ALOGI("using audio bitrate of %d bps, video bitrate of %d bps",
          audioBitrate, videoBitrate);

    if (isAudio) {
        mOutputFormat->setInt32("bitrate", audioBitrate);
    } else {
        mOutputFormat->setInt32("bitrate", videoBitrate);
/*
typedef enum OMX_VIDEO_CONTROLRATETYPE {
    OMX_Video_ControlRateDisable,
    OMX_Video_ControlRateVariable,
    OMX_Video_ControlRateConstant,
*/   
        mOutputFormat->setInt32("bitrate-mode", OMX_Video_ControlRateConstant);
        mOutputFormat->setInt32("frame-rate", 25);
        mOutputFormat->setInt32("i-frame-interval", 1);  // Iframes every 15 secs
    //        OMX_VIDEO_AVCProfileBaseline = 0x01,   /**< Baseline profile */
     mOutputFormat->setInt32("profile", OMX_VIDEO_AVCProfileBaseline);
    //    OMX_VIDEO_AVCLevel4   = 0x800,    /**< Level 4 */
        mOutputFormat->setInt32("level",OMX_VIDEO_AVCLevel4);

        // Configure encoder to use intra macroblock refresh mode
    //    mOutputFormat->setInt32("intra-refresh-mode", OMX_VIDEO_IntraRefreshCyclic);

        int width, height, mbs;
        if (!mOutputFormat->findInt32("width", &width)
                || !mOutputFormat->findInt32("height", &height)) {
            return ERROR_UNSUPPORTED;
        }

        // Update macroblocks in a cyclic fashion with 10% of all MBs within
        // frame gets updated at one time. It takes about 10 frames to
        // completely update a whole video frame. If the frame rate is 30,
        // it takes about 333 ms in the best case (if next frame is not an IDR)
        // to recover from a lost/corrupted packet.
        mbs = (((width + 15) / 16) * ((height + 15) / 16) * 10) / 100;
        mOutputFormat->setInt32("intra-refresh-CIR-mbs", mbs);
    }

    ALOGV("output format is '%s'", mOutputFormat->debugString(0).c_str());

    mNeedToManuallyPrependSPSPPS = false;

    status_t err = NO_INIT;

    if (!isAudio) {
        sp<AMessage> tmp = mOutputFormat->dup();
        tmp->setInt32("prepend-sps-pps-to-idr-frames", 1);

        err = mEncoder->configure(
                tmp,
                NULL /* nativeWindow */,
                NULL /* crypto */,
                MediaCodec::CONFIGURE_FLAG_ENCODE);

        if (err == OK) {
            // Encoder supported prepending SPS/PPS, we don't need to emulate
            // it.
            mOutputFormat = tmp;
        } else {
            mNeedToManuallyPrependSPSPPS = true;

            ALOGI("We going to manually prepend SPS and PPS to IDR frames.");
        }
    }

    if (err != OK) {
        // We'll get here for audio or if we failed to configure the encoder
        // to automatically prepend SPS/PPS in the case of video.

        err = mEncoder->configure(
                    mOutputFormat,
                    NULL /* nativeWindow */,
                    NULL /* crypto */,
                    MediaCodec::CONFIGURE_FLAG_ENCODE);
    }

    if (err != OK) {
        return err;
    }

    err = mEncoder->start();

    if (err != OK) {
        return err;
    }

    err = mEncoder->getInputBuffers(&mEncoderInputBuffers);

    if (err != OK) {
        return err;
    }

    return mEncoder->getOutputBuffers(&mEncoderOutputBuffers);
}

frameworksavmedialibstagefrightwifi-displaysourceMediaPuller.cpp

case kWhatPull:
{
    int32_t generation;
    CHECK(msg->findInt32("generation", &generation));

    if (generation != mPullGeneration) {
        break;
    }

    MediaBuffer *mbuf;
    status_t err = mSource->read(&mbuf);

    if (mPaused) {
        if (err == OK) {
            mbuf->release();
            mbuf = NULL;
        }

        schedulePull();
        break;
    }

    if (err != OK) {
        if (err == ERROR_END_OF_STREAM) {
            ALOGI("stream ended.");
        } else {
            ALOGE("error %d reading stream.", err);
        }

        sp<AMessage> notify = mNotify->dup();
        notify->setInt32("what", kWhatEOS);
        notify->post();
    } else {
        int64_t timeUs;
        CHECK(mbuf->meta_data()->findInt64(kKeyTime, &timeUs));