C++ sp::dequeueOutputBuffer方法代码示例

/*
 * Runs the MediaCodec encoder, sending the output to the MediaMuxer.  The
 * input frames are coming from the virtual display as fast as SurfaceFlinger
 * wants to send them.
 *
 * The muxer must *not* have been started before calling.
 */
static status_t runEncoder(const sp<MediaCodec>& encoder,
        const sp<MediaMuxer>& muxer) {
    static int kTimeout = 250000;   // be responsive on signal
    status_t err;
    ssize_t trackIdx = -1;
    uint32_t debugNumFrames = 0;
    int64_t startWhenNsec = systemTime(CLOCK_MONOTONIC);
    int64_t endWhenNsec = startWhenNsec + seconds_to_nanoseconds(gTimeLimitSec);

    Vector<sp<ABuffer> > buffers;
    err = encoder->getOutputBuffers(&buffers);
    if (err != NO_ERROR) {
        fprintf(stderr, "Unable to get output buffers (err=%d)\n", err);
        return err;
    }

    // This is set by the signal handler.
    gStopRequested = false;

    // Run until we're signaled.
    while (!gStopRequested) {
        size_t bufIndex, offset, size;
        int64_t ptsUsec;
        uint32_t flags;

        if (systemTime(CLOCK_MONOTONIC) > endWhenNsec) {
            if (gVerbose) {
                printf("Time limit reached\n");
            }
            break;
        }

        ALOGV("Calling dequeueOutputBuffer");
        err = encoder->dequeueOutputBuffer(&bufIndex, &offset, &size, &ptsUsec,
                &flags, kTimeout);
        ALOGV("dequeueOutputBuffer returned %d", err);
        switch (err) {
        case NO_ERROR:
            // got a buffer
            if ((flags & MediaCodec::BUFFER_FLAG_CODECCONFIG) != 0) {
                // ignore this -- we passed the CSD into MediaMuxer when
                // we got the format change notification
                ALOGV("Got codec config buffer (%u bytes); ignoring", size);
                size = 0;
            }
            if (size != 0) {
                ALOGV("Got data in buffer %d, size=%d, pts=%lld",
                        bufIndex, size, ptsUsec);
                CHECK(trackIdx != -1);

                // If the virtual display isn't providing us with timestamps,
                // use the current time.
                if (ptsUsec == 0) {
                    ptsUsec = systemTime(SYSTEM_TIME_MONOTONIC) / 1000;
                }

                // The MediaMuxer docs are unclear, but it appears that we
                // need to pass either the full set of BufferInfo flags, or
                // (flags & BUFFER_FLAG_SYNCFRAME).
                err = muxer->writeSampleData(buffers[bufIndex], trackIdx,
                        ptsUsec, flags);
                if (err != NO_ERROR) {
                    fprintf(stderr, "Failed writing data to muxer (err=%d)\n",
                            err);
                    return err;
                }
                debugNumFrames++;
            }
            err = encoder->releaseOutputBuffer(bufIndex);
            if (err != NO_ERROR) {
                fprintf(stderr, "Unable to release output buffer (err=%d)\n",
                        err);
                return err;
            }
            if ((flags & MediaCodec::BUFFER_FLAG_EOS) != 0) {
                // Not expecting EOS from SurfaceFlinger.  Go with it.
                ALOGD("Received end-of-stream");
                gStopRequested = false;
            }
            break;
        case -EAGAIN:                       // INFO_TRY_AGAIN_LATER
            ALOGV("Got -EAGAIN, looping");
            break;
        case INFO_FORMAT_CHANGED:           // INFO_OUTPUT_FORMAT_CHANGED
            {
                // format includes CSD, which we must provide to muxer
                ALOGV("Encoder format changed");
                sp<AMessage> newFormat;
                encoder->getOutputFormat(&newFormat);
                trackIdx = muxer->addTrack(newFormat);
                ALOGV("Starting muxer");
                err = muxer->start();
                if (err != NO_ERROR) {
//.........这里部分代码省略.........

//.........这里部分代码省略.........

    // This is set by the signal handler.
    gStopRequested = false;

    jni_onRecordingStarted();
    // Run until we're signaled.
    while (!gStopRequested) {
        size_t bufIndex, offset, size;
        int64_t ptsUsec;
        uint32_t flags;

        if (systemTime(CLOCK_MONOTONIC) > endWhenNsec) {
            if (gVerbose) {
                printf("Time limit reached\n");
            }
            break;
        }

        // first lets send some audio off to the audio encoder if enabled
        if (gRecordAudio) {
            err = audioEncoder->dequeueInputBuffer(&bufIndex, kTimeout);
            if (err == NO_ERROR) {
                ssize_t audioSize = audioRecorder->read(audioInputBuffers[bufIndex]->data(), kSamplesPerFrame);
                err = audioEncoder->queueInputBuffer(
                        bufIndex,
                        0,
                        audioSize,
                        systemTime(CLOCK_MONOTONIC) / 1000,
                        0);
                ALOGV("Queued %d bytes of audio", audioSize);
            }
        }

        ALOGV("Calling dequeueOutputBuffer");
        err = videoEncoder->dequeueOutputBuffer(&bufIndex, &offset, &size, &ptsUsec,
                &flags, kTimeout);
        ALOGV("dequeueOutputBuffer returned %d", err);
        switch (err) {
        case NO_ERROR:
            // got a buffer
            if ((flags & MediaCodec::BUFFER_FLAG_CODECCONFIG) != 0) {
                // ignore this -- we passed the CSD into MediaMuxer when
                // we got the format change notification
                ALOGV("Got codec config buffer (%u bytes); ignoring", size);
                size = 0;
            }
            if (size != 0) {
                ALOGV("Got data in video buffer %d, size=%d, pts=%lld",
                        bufIndex, size, ptsUsec);
                CHECK(videoTrackIdx != -1);

                // If the virtual display isn't providing us with timestamps,
                // use the current time.
                if (ptsUsec == 0) {
                    ptsUsec = systemTime(SYSTEM_TIME_MONOTONIC) / 1000;
                }

                // The MediaMuxer docs are unclear, but it appears that we
                // need to pass either the full set of BufferInfo flags, or
                // (flags & BUFFER_FLAG_SYNCFRAME).
                err = muxer->writeSampleData(buffers[bufIndex], videoTrackIdx,
                        ptsUsec, flags);
                if (err != NO_ERROR) {
                    fprintf(stderr, "Failed writing data to muxer (err=%d)\n",
                            err);
                    return err;