// The MediaStreamGraph guarantees that this is actually one block, for
// AudioNodeStreams.
void
AudioNodeStream::ProcessInput(GraphTime aFrom, GraphTime aTo, uint32_t aFlags)
{
  EnsureTrack(AUDIO_TRACK, mSampleRate);
  // No more tracks will be coming
  mBuffer.AdvanceKnownTracksTime(STREAM_TIME_MAX);

  uint16_t outputCount = std::max(uint16_t(1), mEngine->OutputCount());
  mLastChunks.SetLength(outputCount);

  // Consider this stream blocked if it has already finished output. Normally
  // mBlocked would reflect this, but due to rounding errors our audio track may
  // appear to extend slightly beyond aFrom, so we might not be blocked yet.
  bool blocked = mFinished || mBlocked.GetAt(aFrom);
  // If the stream has finished at this time, it will be blocked.
  if (mMuted || blocked) {
    for (uint16_t i = 0; i < outputCount; ++i) {
      mLastChunks[i].SetNull(WEBAUDIO_BLOCK_SIZE);
    }
  } else {
    // We need to generate at least one input
    uint16_t maxInputs = std::max(uint16_t(1), mEngine->InputCount());
    OutputChunks inputChunks;
    inputChunks.SetLength(maxInputs);
    for (uint16_t i = 0; i < maxInputs; ++i) {
      ObtainInputBlock(inputChunks[i], i);
    }
    bool finished = false;
    if (maxInputs <= 1 && mEngine->OutputCount() <= 1) {
      mEngine->ProcessBlock(this, inputChunks[0], &mLastChunks[0], &finished);
    } else {
      mEngine->ProcessBlocksOnPorts(this, inputChunks, mLastChunks, &finished);
    }
    for (uint16_t i = 0; i < outputCount; ++i) {
      NS_ASSERTION(mLastChunks[i].GetDuration() == WEBAUDIO_BLOCK_SIZE,
                   "Invalid WebAudio chunk size");
    }
    if (finished) {
      mMarkAsFinishedAfterThisBlock = true;
    }

    if (mDisabledTrackIDs.Contains(static_cast<TrackID>(AUDIO_TRACK))) {
      for (uint32_t i = 0; i < outputCount; ++i) {
        mLastChunks[i].SetNull(WEBAUDIO_BLOCK_SIZE);
      }
    }
  }

  if (!blocked) {
    // Don't output anything while blocked
    AdvanceOutputSegment();
    if (mMarkAsFinishedAfterThisBlock && (aFlags & ALLOW_FINISH)) {
      // This stream was finished the last time that we looked at it, and all
      // of the depending streams have finished their output as well, so now
      // it's time to mark this stream as finished.
      FinishOutput();
    }
  }
}
// The MediaStreamGraph guarantees that this is actually one block, for
// AudioNodeStreams.
void
AudioNodeStream::ProduceOutput(GraphTime aFrom, GraphTime aTo)
{
  if (mMarkAsFinishedAfterThisBlock) {
    // This stream was finished the last time that we looked at it, and all
    // of the depending streams have finished their output as well, so now
    // it's time to mark this stream as finished.
    FinishOutput();
  }

  StreamBuffer::Track* track = EnsureTrack();

  AudioSegment* segment = track->Get<AudioSegment>();

  mLastChunks.SetLength(1);
  mLastChunks[0].SetNull(0);

  if (mInCycle) {
    // XXX DelayNode not supported yet so just produce silence
    mLastChunks[0].SetNull(WEBAUDIO_BLOCK_SIZE);
  } else {
    // We need to generate at least one input
    uint16_t maxInputs = std::max(uint16_t(1), mEngine->InputCount());
    OutputChunks inputChunks;
    inputChunks.SetLength(maxInputs);
    for (uint16_t i = 0; i < maxInputs; ++i) {
      ObtainInputBlock(inputChunks[i], i);
    }
    bool finished = false;
    if (maxInputs <= 1 && mEngine->OutputCount() <= 1) {
      mEngine->ProduceAudioBlock(this, inputChunks[0], &mLastChunks[0], &finished);
    } else {
      mEngine->ProduceAudioBlocksOnPorts(this, inputChunks, mLastChunks, &finished);
    }
    if (finished) {
      mMarkAsFinishedAfterThisBlock = true;
    }
  }

  if (mKind == MediaStreamGraph::EXTERNAL_STREAM) {
    segment->AppendAndConsumeChunk(&mLastChunks[0]);
  } else {
    segment->AppendNullData(mLastChunks[0].GetDuration());
  }

  for (uint32_t j = 0; j < mListeners.Length(); ++j) {
    MediaStreamListener* l = mListeners[j];
    AudioChunk copyChunk = mLastChunks[0];
    AudioSegment tmpSegment;
    tmpSegment.AppendAndConsumeChunk(&copyChunk);
    l->NotifyQueuedTrackChanges(Graph(), AUDIO_NODE_STREAM_TRACK_ID,
                                IdealAudioRate(), segment->GetDuration(), 0,
                                tmpSegment);
  }
}
// The MediaStreamGraph guarantees that this is actually one block, for
// AudioNodeStreams.
void
AudioNodeStream::ProduceOutput(GraphTime aFrom, GraphTime aTo)
{
  if (mMarkAsFinishedAfterThisBlock) {
    // This stream was finished the last time that we looked at it, and all
    // of the depending streams have finished their output as well, so now
    // it's time to mark this stream as finished.
    FinishOutput();
  }

  EnsureTrack(AUDIO_NODE_STREAM_TRACK_ID, mSampleRate);

  uint16_t outputCount = std::max(uint16_t(1), mEngine->OutputCount());
  mLastChunks.SetLength(outputCount);

  if (mInCycle) {
    // XXX DelayNode not supported yet so just produce silence
    for (uint16_t i = 0; i < outputCount; ++i) {
      mLastChunks[i].SetNull(WEBAUDIO_BLOCK_SIZE);
    }
  } else {
    for (uint16_t i = 0; i < outputCount; ++i) {
      mLastChunks[i].SetNull(0);
    }

    // We need to generate at least one input
    uint16_t maxInputs = std::max(uint16_t(1), mEngine->InputCount());
    OutputChunks inputChunks;
    inputChunks.SetLength(maxInputs);
    for (uint16_t i = 0; i < maxInputs; ++i) {
      ObtainInputBlock(inputChunks[i], i);
    }
    bool finished = false;
    if (maxInputs <= 1 && mEngine->OutputCount() <= 1) {
      mEngine->ProduceAudioBlock(this, inputChunks[0], &mLastChunks[0], &finished);
    } else {
      mEngine->ProduceAudioBlocksOnPorts(this, inputChunks, mLastChunks, &finished);
    }
    if (finished) {
      mMarkAsFinishedAfterThisBlock = true;
    }
  }

  if (mDisabledTrackIDs.Contains(AUDIO_NODE_STREAM_TRACK_ID)) {
    for (uint32_t i = 0; i < mLastChunks.Length(); ++i) {
      mLastChunks[i].SetNull(WEBAUDIO_BLOCK_SIZE);
    }
  }

  AdvanceOutputSegment();
}
Exemple #4
0
void PageRecord::StopPage(bool save) {

	if(!m_page_started)
		return;

	StopOutput(true);
	StopInput();

	Logger::LogInfo("[PageRecord::StopPage] " + tr("Stopping page ..."));

	if(m_output_manager != NULL) {

		// stop the output
		if(save)
			FinishOutput();
		m_output_manager.reset();

		// delete the file if it isn't needed
		if(!save && m_file_protocol.isNull()) {
			if(QFileInfo(m_output_settings.file).exists())
				QFile(m_output_settings.file).remove();
		}

	}

	// destroy the GLInject input
	m_gl_inject_input.reset();

	// stop JACK input
#if SSR_USE_JACK
	m_jack_input.reset();
#endif

	Logger::LogInfo("[PageRecord::StopPage] " + tr("Stopped page."));

	m_page_started = false;
	UpdateSysTray();
	OnUpdateSoundNotifications();

	m_timer_update_info->stop();
	OnUpdateInformation();

}
// The MediaStreamGraph guarantees that this is actually one block, for
// AudioNodeStreams.
void
AudioNodeStream::ProduceOutput(GraphTime aFrom, GraphTime aTo)
{
  StreamBuffer::Track* track = EnsureTrack();

  AudioChunk outputChunk;
  AudioSegment* segment = track->Get<AudioSegment>();

  outputChunk.SetNull(0);

  if (mInCycle) {
    // XXX DelayNode not supported yet so just produce silence
    outputChunk.SetNull(WEBAUDIO_BLOCK_SIZE);
  } else {
    AudioChunk tmpChunk;
    AudioChunk* inputChunk = ObtainInputBlock(&tmpChunk);
    bool finished = false;
    mEngine->ProduceAudioBlock(this, *inputChunk, &outputChunk, &finished);
    if (finished) {
      FinishOutput();
    }
  }

  mLastChunk = outputChunk;
  if (mKind == MediaStreamGraph::EXTERNAL_STREAM) {
    segment->AppendAndConsumeChunk(&outputChunk);
  } else {
    segment->AppendNullData(outputChunk.GetDuration());
  }

  for (uint32_t j = 0; j < mListeners.Length(); ++j) {
    MediaStreamListener* l = mListeners[j];
    AudioChunk copyChunk = outputChunk;
    AudioSegment tmpSegment;
    tmpSegment.AppendAndConsumeChunk(&copyChunk);
    l->NotifyQueuedTrackChanges(Graph(), AUDIO_NODE_STREAM_TRACK_ID,
                                IdealAudioRate(), segment->GetDuration(), 0,
                                tmpSegment);
  }
}
// The MediaStreamGraph guarantees that this is actually one block, for
// AudioNodeStreams.
void
AudioNodeStream::ProcessInput(GraphTime aFrom, GraphTime aTo, uint32_t aFlags)
{
  uint16_t outputCount = mLastChunks.Length();
  MOZ_ASSERT(outputCount == std::max(uint16_t(1), mEngine->OutputCount()));

  if (!mIsActive) {
    // mLastChunks are already null.
#ifdef DEBUG
    for (const auto& chunk : mLastChunks) {
      MOZ_ASSERT(chunk.IsNull());
    }
#endif
  } else if (InMutedCycle()) {
    mInputChunks.Clear();
    for (uint16_t i = 0; i < outputCount; ++i) {
      mLastChunks[i].SetNull(WEBAUDIO_BLOCK_SIZE);
    }
  } else {
    // We need to generate at least one input
    uint16_t maxInputs = std::max(uint16_t(1), mEngine->InputCount());
    mInputChunks.SetLength(maxInputs);
    for (uint16_t i = 0; i < maxInputs; ++i) {
      ObtainInputBlock(mInputChunks[i], i);
    }
    bool finished = false;
    if (mPassThrough) {
      MOZ_ASSERT(outputCount == 1, "For now, we only support nodes that have one output port");
      mLastChunks[0] = mInputChunks[0];
    } else {
      if (maxInputs <= 1 && outputCount <= 1) {
        mEngine->ProcessBlock(this, aFrom,
                              mInputChunks[0], &mLastChunks[0], &finished);
      } else {
        mEngine->ProcessBlocksOnPorts(this, mInputChunks, mLastChunks, &finished);
      }
    }
    for (uint16_t i = 0; i < outputCount; ++i) {
      NS_ASSERTION(mLastChunks[i].GetDuration() == WEBAUDIO_BLOCK_SIZE,
                   "Invalid WebAudio chunk size");
    }
    if (finished) {
      mMarkAsFinishedAfterThisBlock = true;
      if (mIsActive) {
        ScheduleCheckForInactive();
      }
    }

    if (mDisabledTrackIDs.Contains(static_cast<TrackID>(AUDIO_TRACK))) {
      for (uint32_t i = 0; i < outputCount; ++i) {
        mLastChunks[i].SetNull(WEBAUDIO_BLOCK_SIZE);
      }
    }
  }

  if (!mFinished) {
    // Don't output anything while finished
    if (mFlags & EXTERNAL_OUTPUT) {
      AdvanceOutputSegment();
    }
    if (mMarkAsFinishedAfterThisBlock && (aFlags & ALLOW_FINISH)) {
      // This stream was finished the last time that we looked at it, and all
      // of the depending streams have finished their output as well, so now
      // it's time to mark this stream as finished.
      if (mFlags & EXTERNAL_OUTPUT) {
        FinishOutput();
      }
      FinishOnGraphThread();
    }
  }
}
// The MediaStreamGraph guarantees that this is actually one block, for
// AudioNodeStreams.
void
AudioNodeStream::ProcessInput(GraphTime aFrom, GraphTime aTo, uint32_t aFlags)
{
  if (!mFinished) {
    EnsureTrack(AUDIO_TRACK);
  }
  // No more tracks will be coming
  mBuffer.AdvanceKnownTracksTime(STREAM_TIME_MAX);

  uint16_t outputCount = mLastChunks.Length();
  MOZ_ASSERT(outputCount == std::max(uint16_t(1), mEngine->OutputCount()));

  // Consider this stream blocked if it has already finished output. Normally
  // mBlocked would reflect this, but due to rounding errors our audio track may
  // appear to extend slightly beyond aFrom, so we might not be blocked yet.
  bool blocked = mFinished || mBlocked.GetAt(aFrom);
  // If the stream has finished at this time, it will be blocked.
  if (blocked || InMutedCycle()) {
    mInputChunks.Clear();
    for (uint16_t i = 0; i < outputCount; ++i) {
      mLastChunks[i].SetNull(WEBAUDIO_BLOCK_SIZE);
    }
  } else {
    // We need to generate at least one input
    uint16_t maxInputs = std::max(uint16_t(1), mEngine->InputCount());
    mInputChunks.SetLength(maxInputs);
    for (uint16_t i = 0; i < maxInputs; ++i) {
      ObtainInputBlock(mInputChunks[i], i);
    }
    bool finished = false;
    if (mPassThrough) {
      MOZ_ASSERT(outputCount == 1, "For now, we only support nodes that have one output port");
      mLastChunks[0] = mInputChunks[0];
    } else {
      if (maxInputs <= 1 && outputCount <= 1) {
        mEngine->ProcessBlock(this, mInputChunks[0], &mLastChunks[0], &finished);
      } else {
        mEngine->ProcessBlocksOnPorts(this, mInputChunks, mLastChunks, &finished);
      }
    }
    for (auto& chunk : mInputChunks) {
      // If the buffer is shared then it won't be reused, so release the
      // reference now.  Keep the channel data array to save a free/alloc
      // pair.
      chunk.ReleaseBufferIfShared();
    }
    for (uint16_t i = 0; i < outputCount; ++i) {
      NS_ASSERTION(mLastChunks[i].GetDuration() == WEBAUDIO_BLOCK_SIZE,
                   "Invalid WebAudio chunk size");
    }
    if (finished) {
      mMarkAsFinishedAfterThisBlock = true;
    }

    if (mDisabledTrackIDs.Contains(static_cast<TrackID>(AUDIO_TRACK))) {
      for (uint32_t i = 0; i < outputCount; ++i) {
        mLastChunks[i].SetNull(WEBAUDIO_BLOCK_SIZE);
      }
    }
  }

  if (!blocked) {
    // Don't output anything while blocked
    AdvanceOutputSegment();
    if (mMarkAsFinishedAfterThisBlock && (aFlags & ALLOW_FINISH)) {
      // This stream was finished the last time that we looked at it, and all
      // of the depending streams have finished their output as well, so now
      // it's time to mark this stream as finished.
      FinishOutput();
    }
  }
}
Exemple #8
0
void PageRecord::StartPage() {

	if(m_page_started)
		return;

	assert(!m_input_started);
	assert(!m_output_started);

	// save the settings in case libav/ffmpeg decides to kill the process
	m_main_window->SaveSettings();

	// clear the log
	m_textedit_log->clear();

	// clear the preview
	if(m_previewing) {
		m_video_previewer->Reset();
		m_audio_previewer->Reset();
	}

	PageInput *page_input = m_main_window->GetPageInput();
	PageOutput *page_output = m_main_window->GetPageOutput();

	// get the video input settings
	m_video_area = page_input->GetVideoArea();
	m_video_area_follow_fullscreen = page_input->GetVideoAreaFollowFullscreen();
	m_video_x = page_input->GetVideoX();
	m_video_y = page_input->GetVideoY();
#if SSR_USE_OPENGL_RECORDING
	if(m_video_area == PageInput::VIDEO_AREA_GLINJECT) {
		m_video_in_width = 0;
		m_video_in_height = 0;
	} else {
#else
	{
#endif
		m_video_in_width = page_input->GetVideoW();
		m_video_in_height = page_input->GetVideoH();
	}
	m_video_in_width = page_input->GetVideoW();
	m_video_in_height = page_input->GetVideoH();
	m_video_frame_rate = page_input->GetVideoFrameRate();
	m_video_scaling = page_input->GetVideoScalingEnabled();
	m_video_scaled_width = page_input->GetVideoScaledW();
	m_video_scaled_height = page_input->GetVideoScaledH();
	m_video_record_cursor = page_input->GetVideoRecordCursor();

	// get the audio input settings
	m_audio_enabled = page_input->GetAudioEnabled();
	m_audio_channels = 2;
	m_audio_sample_rate = 48000;
	m_audio_backend = page_input->GetAudioBackend();
#if SSR_USE_ALSA
	m_alsa_source = page_input->GetALSASourceName();
#endif
#if SSR_USE_PULSEAUDIO
	m_pulseaudio_source = page_input->GetPulseAudioSourceName();
#endif
#if SSR_USE_JACK
	bool jack_connect_system_capture = page_input->GetJackConnectSystemCapture();
	bool jack_connect_system_playback = page_input->GetJackConnectSystemPlayback();
#endif

	// override sample rate for problematic cases (these are hard-coded for now)
	if(page_output->GetContainer() == PageOutput::CONTAINER_OTHER && page_output->GetContainerAVName() == "flv") {
		m_audio_sample_rate = 44100;
	}

#if SSR_USE_OPENGL_RECORDING
	// get the glinject settings
	QString glinject_channel = page_input->GetGLInjectChannel();
	bool glinject_relax_permissions = page_input->GetGLInjectRelaxPermissions();
	QString glinject_command = page_input->GetGLInjectCommand();
	QString glinject_working_directory = page_input->GetGLInjectWorkingDirectory();
	bool glinject_auto_launch = page_input->GetGLInjectAutoLaunch();
	bool glinject_limit_fps = page_input->GetGLInjectLimitFPS();
#endif

	// get file settings
	m_file_base = page_output->GetFile();
	m_file_protocol = page_output->GetFileProtocol();
	m_separate_files = page_output->GetSeparateFiles();
	m_add_timestamp = page_output->GetAddTimestamp();

	// get the output settings
	m_output_settings.file = QString(); // will be set later
	m_output_settings.container_avname = page_output->GetContainerAVName();

	m_output_settings.video_codec_avname = page_output->GetVideoCodecAVName();
	m_output_settings.video_kbit_rate = page_output->GetVideoKBitRate();
	m_output_settings.video_options.clear();
	m_output_settings.video_width = 0;
	m_output_settings.video_height = 0;
	m_output_settings.video_frame_rate = m_video_frame_rate;
	m_output_settings.video_allow_frame_skipping = page_output->GetVideoAllowFrameSkipping();

	m_output_settings.audio_codec_avname = (m_audio_enabled)? page_output->GetAudioCodecAVName() : QString();
	m_output_settings.audio_kbit_rate = page_output->GetAudioKBitRate();
	m_output_settings.audio_options.clear();
	m_output_settings.audio_channels = m_audio_channels;
	m_output_settings.audio_sample_rate = m_audio_sample_rate;

	// some codec-specific things
	// you can get more information about all these options by running 'ffmpeg -h' or 'avconv -h' from a terminal
	switch(page_output->GetVideoCodec()) {
		case PageOutput::VIDEO_CODEC_H264: {
			// x264 has a 'constant quality' mode, where the bit rate is simply set to whatever is needed to keep a certain quality. The quality is set
			// with the 'crf' option. 'preset' changes the encoding speed (and hence the efficiency of the compression) but doesn't really influence the quality,
			// which is great because it means you don't have to experiment with different bit rates and different speeds to get good results.
			m_output_settings.video_options.push_back(std::make_pair(QString("crf"), QString::number(page_output->GetH264CRF())));
			m_output_settings.video_options.push_back(std::make_pair(QString("preset"), EnumToString(page_output->GetH264Preset())));
			break;
		}
		case PageOutput::VIDEO_CODEC_VP8: {
			// The names of there parameters are very unintuitive. The two options we care about (because they change the speed) are 'deadline' and 'cpu-used'.
			// 'deadline=best' is unusably slow. 'deadline=good' is the normal setting, it tells the encoder to use the speed set with 'cpu-used'. Higher
			// numbers will use *less* CPU, confusingly, so a higher number is faster. I haven't done much testing with 'realtime' so I'm not sure if it's a good idea here.
			// It sounds useful, but I think it will use so much CPU that it will slow down the program that is being recorded.
			m_output_settings.video_options.push_back(std::make_pair(QString("deadline"), QString("good")));
			m_output_settings.video_options.push_back(std::make_pair(QString("cpu-used"), QString::number(page_output->GetVP8CPUUsed())));
			break;
		}
		case PageOutput::VIDEO_CODEC_OTHER: {
			m_output_settings.video_options = GetOptionsFromString(page_output->GetVideoOptions());
			break;
		}
		default: break; // to keep GCC happy
	}
	switch(page_output->GetAudioCodec()) {
		case PageOutput::AUDIO_CODEC_OTHER: {
			m_output_settings.audio_options = GetOptionsFromString(page_output->GetAudioOptions());
			break;
		}
		default: break; // to keep GCC happy
	}

	// hide the audio previewer if there is no audio
	GroupVisible({m_label_mic_icon, m_audio_previewer}, m_audio_enabled);

	Logger::LogInfo("[PageRecord::StartPage] " + tr("Starting page ..."));


	try {

#if SSR_USE_OPENGL_RECORDING
		// for OpenGL recording, create the input now
		if(m_video_area == PageInput::VIDEO_AREA_GLINJECT) {
			if(glinject_auto_launch)
				GLInjectInput::LaunchApplication(glinject_channel, glinject_relax_permissions, glinject_command, glinject_working_directory);
			m_gl_inject_input.reset(new GLInjectInput(glinject_channel, glinject_relax_permissions, m_video_record_cursor, glinject_limit_fps, m_video_frame_rate));
		}
#endif

#if SSR_USE_JACK
		if(m_audio_enabled) {
			// for JACK, start the input now
			if(m_audio_backend == PageInput::AUDIO_BACKEND_JACK)
				m_jack_input.reset(new JACKInput(jack_connect_system_capture, jack_connect_system_playback));
		}
#endif

	} catch(...) {
		Logger::LogError("[PageRecord::StartPage] " + tr("Error: Something went wrong during initialization."));
#if SSR_USE_OPENGL_RECORDING
		m_gl_inject_input.reset();
#endif
#if SSR_USE_JACK
		m_jack_input.reset();
#endif
	}

	Logger::LogInfo("[PageRecord::StartPage] " + tr("Started page."));

	m_page_started = true;
	m_recorded_something = false;
	m_wait_saving = false;
	m_error_occurred = false;
	UpdateSysTray();
#if SSR_USE_ALSA
	OnUpdateSoundNotifications();
#endif

	UpdateInput();

	OnUpdateInformation();
	m_timer_update_info->start(1000);

}

void PageRecord::StopPage(bool save) {

	if(!m_page_started)
		return;

	StopOutput(true);
	StopInput();

	Logger::LogInfo("[PageRecord::StopPage] " + tr("Stopping page ..."));

	if(m_output_manager != NULL) {

		// stop the output
		if(save)
			FinishOutput();
		m_output_manager.reset();

		// delete the file if it isn't needed
		if(!save && m_file_protocol.isNull()) {
			if(QFileInfo(m_output_settings.file).exists())
				QFile(m_output_settings.file).remove();
		}

	}

#if SSR_USE_OPENGL_RECORDING
	// stop GLInject input
	m_gl_inject_input.reset();
#endif

#if SSR_USE_JACK
	// stop JACK input
	m_jack_input.reset();
#endif

	Logger::LogInfo("[PageRecord::StopPage] " + tr("Stopped page."));

	m_page_started = false;
	UpdateSysTray();
#if SSR_USE_ALSA
	OnUpdateSoundNotifications();
#endif

	m_timer_update_info->stop();
	OnUpdateInformation();

}

void PageRecord::StartOutput() {
	assert(m_page_started);

	if(m_output_started)
		return;

#if SSR_USE_ALSA
	if(m_simple_synth != NULL) {
		m_simple_synth->PlaySequence(SEQUENCE_RECORD_START.data(), SEQUENCE_RECORD_START.size());
		usleep(200000);
	}
#endif

	try {

		Logger::LogInfo("[PageRecord::StartOutput] " + tr("Starting output ..."));

		if(m_output_manager == NULL) {

			// set the file name
			m_output_settings.file = GetNewSegmentFile(m_file_base, m_add_timestamp);

			// for X11 recording, update the video size (if possible)
			if(m_x11_input != NULL)
				m_x11_input->GetCurrentSize(&m_video_in_width, &m_video_in_height);

#if SSR_USE_OPENGL_RECORDING
			// for OpenGL recording, detect the video size
			if(m_video_area == PageInput::VIDEO_AREA_GLINJECT && !m_video_scaling) {
				if(m_gl_inject_input == NULL) {
					Logger::LogError("[PageRecord::StartOutput] " + tr("Error: Could not get the size of the OpenGL application because the GLInject input has not been created."));
					throw GLInjectException();
				}
				m_gl_inject_input->GetCurrentSize(&m_video_in_width, &m_video_in_height);
				if(m_video_in_width == 0 && m_video_in_height == 0) {
					Logger::LogError("[PageRecord::StartOutput] " + tr("Error: Could not get the size of the OpenGL application. Either the "
									 "application wasn't started correctly, or the application hasn't created an OpenGL window yet. If "
									 "you want to start recording before starting the application, you have to enable scaling and enter "
									 "the video size manually."));
					throw GLInjectException();
				}
			}
#endif

			// calculate the output width and height
			if(m_video_scaling) {
				// Only even width and height is allowed because some pixel formats (e.g. YUV420) require this.
				m_output_settings.video_width = m_video_scaled_width / 2 * 2;
				m_output_settings.video_height = m_video_scaled_height / 2 * 2;
#if SSR_USE_OPENGL_RECORDING
			} else if(m_video_area == PageInput::VIDEO_AREA_GLINJECT) {
				// The input size is the size of the OpenGL application and can't be changed. The output size is set to the current size of the application.
				m_output_settings.video_width = m_video_in_width / 2 * 2;
				m_output_settings.video_height = m_video_in_height / 2 * 2;
#endif
			} else {
				// If the user did not explicitly select scaling, then don't force scaling just because the recording area is one pixel too large.
				// One missing row/column of pixels is probably better than a blurry video (and scaling is SLOW).
				m_video_in_width = m_video_in_width / 2 * 2;
				m_video_in_height = m_video_in_height / 2 * 2;
				m_output_settings.video_width = m_video_in_width;
				m_output_settings.video_height = m_video_in_height;
			}

			// start the output
			m_output_manager.reset(new OutputManager(m_output_settings));

		} else {

			// start a new segment
			m_output_manager->GetSynchronizer()->NewSegment();

		}

		Logger::LogInfo("[PageRecord::StartOutput] " + tr("Started output."));

		m_output_started = true;
		m_recorded_something = true;
		UpdateSysTray();
		UpdateRecordPauseButton();
		UpdateInput();

	} catch(...) {
		Logger::LogError("[PageRecord::StartOutput] " + tr("Error: Something went wrong during initialization."));
	}

}