Beispiel #1
0
bool EffectSilence::Process()
{
   if (length <= 0.0)
      length = sDefaultGenerateLen;

   TrackListIterator iter(mWaveTracks);
   WaveTrack *track = (WaveTrack *)iter.First();
   while (track) {
      WaveTrack *tmp = mFactory->NewWaveTrack(track->GetSampleFormat(), track->GetRate());
      tmp->InsertSilence(0.0, length);
      tmp->Flush();
      track->Clear(mT0, mT1);
      track->Paste(mT0, tmp);
      delete tmp;
      
      //Iterate to the next track
      track = (WaveTrack *)iter.Next();
   }

	mT1 = mT0 + length; // Update selection.
   return true;
}
Beispiel #2
0
int FFmpegImportFileHandle::Import(TrackFactory *trackFactory,
              Track ***outTracks,
              int *outNumTracks,
              Tags *tags)
{

   CreateProgress();

   // Remove stream contexts which are not marked for importing and adjust mScs and mNumStreams accordingly
   for (int i = 0; i < mNumStreams;)
   {
      if (!mScs[i]->m_use)
      {
         delete mScs[i];
         for (int j = i; j < mNumStreams - 1; j++)
         {
            mScs[j] = mScs[j+1];
         }
         mNumStreams--;
      }
      else i++;
   }

   mChannels = new WaveTrack **[mNumStreams];
   mNumSamples = 0;

   for (int s = 0; s < mNumStreams; s++)
   {
      // As you can see, it's really a number of frames.
      // TODO: use something other than nb_frames for progress reporting (nb_frames is not available for some formats). Maybe something from the format context?
      mNumSamples += mScs[s]->m_stream->nb_frames;
      // There is a possibility that number of channels will change over time, but we do not have WaveTracks for new channels. Remember the number of channels and stick to it.
      mScs[s]->m_initialchannels = mScs[s]->m_stream->codec->channels;
      mChannels[s] = new WaveTrack *[mScs[s]->m_stream->codec->channels];
      int c;
      for (c = 0; c < mScs[s]->m_stream->codec->channels; c++)
      {
         mChannels[s][c] = trackFactory->NewWaveTrack(int16Sample, mScs[s]->m_stream->codec->sample_rate);

         if (mScs[s]->m_stream->codec->channels == 2)
         {
            switch (c)
            {
            case 0:
               mChannels[s][c]->SetChannel(Track::LeftChannel);
               mChannels[s][c]->SetLinked(true);
               break;
            case 1:
               mChannels[s][c]->SetChannel(Track::RightChannel);
               mChannels[s][c]->SetTeamed(true);
               break;
            }
         }
         else
         {
            mChannels[s][c]->SetChannel(Track::MonoChannel);
         }
      }
   }

   // Handles the start_time by creating silence. This may or may not be correct.
   // There is a possibility that we should ignore first N milliseconds of audio instead. I do not know.
   /// TODO: Nag FFmpeg devs about start_time until they finally say WHAT is this and HOW to handle it.
   for (int s = 0; s < mNumStreams; s++)
   {
      int64_t stream_delay = 0;
      if (mScs[s]->m_stream->start_time != int64_t(AV_NOPTS_VALUE))
      {
         stream_delay = mScs[s]->m_stream->start_time;
         wxLogMessage(wxT("Stream %d start_time = %d, that would be %f milliseconds."), s, mScs[s]->m_stream->start_time, double(mScs[s]->m_stream->start_time)/AV_TIME_BASE*1000);
      }
      if (stream_delay != 0)
      {
         for (int c = 0; c < mScs[s]->m_stream->codec->channels; c++)
         {
            WaveTrack *t = mChannels[s][c];
            t->InsertSilence(0,double(stream_delay)/AV_TIME_BASE);
         }
      }
   }

   // This is the heart of the importing process
   streamContext *sc = NULL;
   // The result of Import() to be returend. It will be something other than zero if user canceled or some error appears.
   int res = 0;
   // Read next frame.
   while ((sc = ReadNextFrame()) != NULL && (res == 0))
   {
      // ReadNextFrame returns 1 if stream is not to be imported
      if (sc != (streamContext*)1)
      {
         // Decode frame until it is not possible to decode any further
         while (sc->m_pktRemainingSiz > 0 && (res == 0))
         {
            if (DecodeFrame(sc,false) < 0)
               break;

            // If something useable was decoded - write it to mChannels
            if (sc->m_frameValid)
               res = WriteData(sc);
         }

         // Cleanup after frame decoding
         if (sc->m_pktValid)
         {
            av_free_packet(&sc->m_pkt);
            sc->m_pktValid = 0;
         }    
      }
   }

   // Flush the decoders.
   if ((mNumStreams != 0) && (res == 0))
   {
      for (int i = 0; i < mNumStreams; i++)
      {
         if (DecodeFrame(mScs[i], true) == 0)
         {
            WriteData(mScs[i]);

            if (mScs[i]->m_pktValid)
            {
               av_free_packet(&mScs[i]->m_pkt);
               mScs[i]->m_pktValid = 0;
            }				
         }
      }
   }

   // Something bad happened - destroy everything!
   if (res)
   {
      for (int s = 0; s < mNumStreams; s++)
      {
         delete[] mChannels[s];
      }
      delete[] mChannels;

      if (mCancelled)
         return eImportCancelled;
      else
         return eImportFailed;
   }

   *outNumTracks = 0;
   for (int s = 0; s < mNumStreams; s++)
   {
      *outNumTracks += mScs[s]->m_stream->codec->channels;
   }

   // Create new tracks
   *outTracks = new Track *[*outNumTracks];

   // Copy audio from mChannels to newly created tracks (destroying mChannels elements in process)
   int trackindex = 0;
   for (int s = 0; s < mNumStreams; s++)
   {
      for(int c = 0; c < mScs[s]->m_stream->codec->channels; c++)
      {
         mChannels[s][c]->Flush();
         (*outTracks)[trackindex++] = mChannels[s][c];
      }
      delete[] mChannels[s];
   }
   delete[] mChannels;

   // Save metadata
   WriteMetadata(mFormatContext,tags);

   return eImportSuccess;
}
Beispiel #3
0
int FFmpegImportFileHandle::Import(TrackFactory *trackFactory,
              Track ***outTracks,
              int *outNumTracks,
              Tags *tags)
{

   CreateProgress();

   // Remove stream contexts which are not marked for importing and adjust mScs and mNumStreams accordingly
   for (int i = 0; i < mNumStreams;)
   {
      if (!mScs[i]->m_use)
      {
         delete mScs[i];
         for (int j = i; j < mNumStreams - 1; j++)
         {
            mScs[j] = mScs[j+1];
         }
         mNumStreams--;
      }
      else i++;
   }

   mChannels = new WaveTrack **[mNumStreams];

   for (int s = 0; s < mNumStreams; s++)
   {
      switch (mScs[s]->m_stream->codec->sample_fmt)
      {
         case SAMPLE_FMT_U8:
         case SAMPLE_FMT_S16:
            mScs[s]->m_osamplesize = sizeof(int16_t);
            mScs[s]->m_osamplefmt = int16Sample;
         break;
         default:
            mScs[s]->m_osamplesize = sizeof(float);
            mScs[s]->m_osamplefmt = floatSample;
         break;
      }

      // There is a possibility that number of channels will change over time, but we do not have WaveTracks for new channels. Remember the number of channels and stick to it.
      mScs[s]->m_initialchannels = mScs[s]->m_stream->codec->channels;
      mChannels[s] = new WaveTrack *[mScs[s]->m_stream->codec->channels];
      int c;
      for (c = 0; c < mScs[s]->m_stream->codec->channels; c++)
      {
         mChannels[s][c] = trackFactory->NewWaveTrack(mScs[s]->m_osamplefmt, mScs[s]->m_stream->codec->sample_rate);

         if (mScs[s]->m_stream->codec->channels == 2)
         {
            switch (c)
            {
            case 0:
               mChannels[s][c]->SetChannel(Track::LeftChannel);
               mChannels[s][c]->SetLinked(true);
               break;
            case 1:
               mChannels[s][c]->SetChannel(Track::RightChannel);
               break;
            }
         }
         else
         {
            mChannels[s][c]->SetChannel(Track::MonoChannel);
         }
      }
   }

   // Handles the start_time by creating silence. This may or may not be correct.
   // There is a possibility that we should ignore first N milliseconds of audio instead. I do not know.
   /// TODO: Nag FFmpeg devs about start_time until they finally say WHAT is this and HOW to handle it.
   for (int s = 0; s < mNumStreams; s++)
   {
      int64_t stream_delay = 0;
      if (mScs[s]->m_stream->start_time != int64_t(AV_NOPTS_VALUE) && mScs[s]->m_stream->start_time > 0)
      {
         stream_delay = mScs[s]->m_stream->start_time;
         wxLogDebug(wxT("Stream %d start_time = %d, that would be %f milliseconds."), s, mScs[s]->m_stream->start_time, double(mScs[s]->m_stream->start_time)/AV_TIME_BASE*1000);
      }
      if (stream_delay != 0)
      {
         for (int c = 0; c < mScs[s]->m_stream->codec->channels; c++)
         {
            WaveTrack *t = mChannels[s][c];
            t->InsertSilence(0,double(stream_delay)/AV_TIME_BASE);
         }
      }
   }
   // This is the heart of the importing process
   // The result of Import() to be returend. It will be something other than zero if user canceled or some error appears.
   int res = eProgressSuccess;

#ifdef EXPERIMENTAL_OD_FFMPEG
   mUsingOD = false;
   gPrefs->Read(wxT("/Library/FFmpegOnDemand"), &mUsingOD);
   //at this point we know the file is good and that we have to load the number of channels in mScs[s]->m_stream->codec->channels;
   //so for OD loading we create the tracks and releasee the modal lock after starting the ODTask.
   if (mUsingOD) {
      std::vector<ODDecodeFFmpegTask*> tasks;
      //append blockfiles to each stream and add an individual ODDecodeTask for each one.
      for (int s = 0; s < mNumStreams; s++) {
         ODDecodeFFmpegTask* odTask=new ODDecodeFFmpegTask(mScs,mNumStreams,mChannels,mFormatContext, s);
         odTask->CreateFileDecoder(mFilename);

         //each stream has different duration.  We need to know it if seeking is to be allowed.
         sampleCount sampleDuration = 0;
         if (mScs[s]->m_stream->duration > 0)
            sampleDuration = ((sampleCount)mScs[s]->m_stream->duration * mScs[s]->m_stream->time_base.num) *mScs[s]->m_stream->codec->sample_rate / mScs[s]->m_stream->time_base.den;
         else
            sampleDuration = ((sampleCount)mFormatContext->duration *mScs[s]->m_stream->codec->sample_rate) / AV_TIME_BASE;

         //      printf(" OD duration samples %qi, sr %d, secs %d\n",sampleDuration, (int)mScs[s]->m_stream->codec->sample_rate,(int)sampleDuration/mScs[s]->m_stream->codec->sample_rate);
         
         //for each wavetrack within the stream add coded blockfiles
         for (int c = 0; c < mScs[s]->m_stream->codec->channels; c++) {
            WaveTrack *t = mChannels[s][c];
            odTask->AddWaveTrack(t);
         
            sampleCount maxBlockSize = t->GetMaxBlockSize();
            //use the maximum blockfile size to divide the sections (about 11secs per blockfile at 44.1khz)
            for (sampleCount i = 0; i < sampleDuration; i += maxBlockSize) {
               sampleCount blockLen = maxBlockSize;
               if (i + blockLen > sampleDuration)
                  blockLen = sampleDuration - i;
            
               t->AppendCoded(mFilename, i, blockLen, c,ODTask::eODFFMPEG);
            
               // This only works well for single streams since we assume 
               // each stream is of the same duration and channels
               res = mProgress->Update(i+sampleDuration*c+ sampleDuration*mScs[s]->m_stream->codec->channels*s, 
                                       sampleDuration*mScs[s]->m_stream->codec->channels*mNumStreams);
               if (res != eProgressSuccess)
                  break;
            }
         }
         tasks.push_back(odTask);
      }
      //Now we add the tasks and let them run, or delete them if the user cancelled
      for(int i=0; i < (int)tasks.size(); i++) {
         if(res==eProgressSuccess)
            ODManager::Instance()->AddNewTask(tasks[i]);
         else
            {
               delete tasks[i];
            }
      }
   } else {
#endif
   streamContext *sc = NULL;

   // Read next frame.
   while ((sc = ReadNextFrame()) != NULL && (res == eProgressSuccess))
   {
      // ReadNextFrame returns 1 if stream is not to be imported
      if (sc != (streamContext*)1)
      {
         // Decode frame until it is not possible to decode any further
         while (sc->m_pktRemainingSiz > 0 && (res == eProgressSuccess || res == eProgressStopped))
         {
            if (DecodeFrame(sc,false) < 0)
               break;

            // If something useable was decoded - write it to mChannels
            if (sc->m_frameValid)
               res = WriteData(sc);
         }

         // Cleanup after frame decoding
         if (sc->m_pktValid)
         {
            av_free_packet(&sc->m_pkt);
            sc->m_pktValid = 0;
         }    
      }
   }

   // Flush the decoders.
   if ((mNumStreams != 0) && (res == eProgressSuccess || res == eProgressStopped))
   {
      for (int i = 0; i < mNumStreams; i++)
      {
         if (DecodeFrame(mScs[i], true) == 0)
         {
            WriteData(mScs[i]);

            if (mScs[i]->m_pktValid)
            {
               av_free_packet(&mScs[i]->m_pkt);
               mScs[i]->m_pktValid = 0;
            }               
         }
      }
   }
#ifdef EXPERIMENTAL_OD_FFMPEG
   } // else -- !mUsingOD == true
#endif   //EXPERIMENTAL_OD_FFMPEG

   // Something bad happened - destroy everything!
   if (res == eProgressCancelled || res == eProgressFailed)
   {
      for (int s = 0; s < mNumStreams; s++)
      {
         delete[] mChannels[s];
      }
      delete[] mChannels;

      return res;
   }
   //else if (res == 2), we just stop the decoding as if the file has ended

   *outNumTracks = 0;
   for (int s = 0; s < mNumStreams; s++)
   {
      *outNumTracks += mScs[s]->m_initialchannels;
   }

   // Create new tracks
   *outTracks = new Track *[*outNumTracks];

   // Copy audio from mChannels to newly created tracks (destroying mChannels elements in process)
   int trackindex = 0;
   for (int s = 0; s < mNumStreams; s++)
   {
      for(int c = 0; c < mScs[s]->m_initialchannels; c++)
      {
         mChannels[s][c]->Flush();
         (*outTracks)[trackindex++] = mChannels[s][c];
      }
      delete[] mChannels[s];
   }
   delete[] mChannels;

   // Save metadata
   WriteMetadata(tags);

   return res;
}
Beispiel #4
0
void ControlToolBar::OnRecord(wxCommandEvent &evt)
{
   if (gAudioIO->IsBusy()) {
      mRecord->PopUp();
      return;
   }
   AudacityProject *p = GetActiveProject();

   if( evt.GetInt() == 1 ) // used when called by keyboard shortcut. Default (0) ignored.
      mRecord->SetShift(true);
   if( evt.GetInt() == 2 )
      mRecord->SetShift(false);

   SetRecord(true, mRecord->WasShiftDown());

   if (p) {
      TrackList *t = p->GetTracks();
      TrackListIterator it(t);
      if(it.First() == NULL)
         mRecord->SetShift(false);
      double t0 = p->GetSel0();
      double t1 = p->GetSel1();
      if (t1 == t0)
         t1 = 1000000000.0;     // record for a long, long time (tens of years)

      /* TODO: set up stereo tracks if that is how the user has set up
       * their preferences, and choose sample format based on prefs */
      WaveTrackArray newRecordingTracks, playbackTracks;
#ifdef EXPERIMENTAL_MIDI_OUT
      NoteTrackArray midiTracks;
#endif
      bool duplex;
      gPrefs->Read(wxT("/AudioIO/Duplex"), &duplex, true);

      if(duplex){
         playbackTracks = t->GetWaveTrackArray(false);
#ifdef EXPERIMENTAL_MIDI_OUT
         midiTracks = t->GetNoteTrackArray(false);
#endif
     }
      else {
         playbackTracks = WaveTrackArray();
#ifdef EXPERIMENTAL_MIDI_OUT
         midiTracks = NoteTrackArray();
#endif
     }

      // If SHIFT key was down, the user wants append to tracks
      int recordingChannels = 0;
      bool shifted = mRecord->WasShiftDown();
      if (shifted) {
         bool sel = false;
         double allt0 = t0;

         // Find the maximum end time of selected and all wave tracks
         // Find whether any tracks were selected.  (If any are selected,
         // record only into them; else if tracks exist, record into all.)
         for (Track *tt = it.First(); tt; tt = it.Next()) {
            if (tt->GetKind() == Track::Wave) {
               WaveTrack *wt = static_cast<WaveTrack *>(tt);
               if (wt->GetEndTime() > allt0) {
                  allt0 = wt->GetEndTime();
               }

               if (tt->GetSelected()) {
                  sel = true;
                  if (wt->GetEndTime() > t0) {
                     t0 = wt->GetEndTime();
                  }
               }
            }
         }

         // Use end time of all wave tracks if none selected
         if (!sel) {
            t0 = allt0;
         }

         // Pad selected/all wave tracks to make them all the same length
         // Remove recording tracks from the list of tracks for duplex ("overdub")
         // playback.
         for (Track *tt = it.First(); tt; tt = it.Next()) {
            if (tt->GetKind() == Track::Wave && (tt->GetSelected() || !sel)) {
               WaveTrack *wt = static_cast<WaveTrack *>(tt);
               if (duplex)
                  playbackTracks.Remove(wt);
               t1 = wt->GetEndTime();
               if (t1 < t0) {
                  WaveTrack *newTrack = p->GetTrackFactory()->NewWaveTrack();
                  newTrack->InsertSilence(0.0, t0 - t1);
                  newTrack->Flush();
                  wt->Clear(t1, t0);
                  bool bResult = wt->Paste(t1, newTrack);
                  wxASSERT(bResult); // TO DO: Actually handle this.
                  delete newTrack;
               }
               newRecordingTracks.Add(wt);
            }
         }

         t1 = 1000000000.0;     // record for a long, long time (tens of years)
      }
      else {
         recordingChannels = gPrefs->Read(wxT("/AudioIO/RecordChannels"), 2);
         for (int c = 0; c < recordingChannels; c++) {
            WaveTrack *newTrack = p->GetTrackFactory()->NewWaveTrack();

            newTrack->SetOffset(t0);

            if (recordingChannels > 2)
              newTrack->SetMinimized(true);

            if (recordingChannels == 2) {
               if (c == 0) {
                  newTrack->SetChannel(Track::LeftChannel);
                  newTrack->SetLinked(true);
               }
               else {
                  newTrack->SetChannel(Track::RightChannel);
               }
            }
            else {
               newTrack->SetChannel( Track::MonoChannel );
            }

            newRecordingTracks.Add(newTrack);
         }

         // msmeyer: StartStream calls a callback which triggers auto-save, so
         // we add the tracks where recording is done into now. We remove them
         // later if starting the stream fails
         for (unsigned int i = 0; i < newRecordingTracks.GetCount(); i++)
            t->Add(newRecordingTracks[i]);
      }

      //Automated Input Level Adjustment Initialization
      #ifdef AUTOMATED_INPUT_LEVEL_ADJUSTMENT
         gAudioIO->AILAInitialize();
      #endif

      int token = gAudioIO->StartStream(playbackTracks,
                                        newRecordingTracks,
#ifdef EXPERIMENTAL_MIDI_OUT
                                        midiTracks,
#endif
                                        t->GetTimeTrack(),
                                        p->GetRate(), t0, t1, p);

      bool success = (token != 0);

      if (success) {
         p->SetAudioIOToken(token);
         mBusyProject = p;
      }
      else {
         // msmeyer: Delete recently added tracks if opening stream fails
         if (!shifted) {
            for (unsigned int i = 0; i < newRecordingTracks.GetCount(); i++) {
               t->Remove(newRecordingTracks[i]);
               delete newRecordingTracks[i];
            }
         }

         // msmeyer: Show error message if stream could not be opened
         wxMessageBox(_("Error while opening sound device. Please check the recording device settings and the project sample rate."),
                      _("Error"), wxOK | wxICON_EXCLAMATION, this);

         SetPlay(false);
         SetStop(false);
         SetRecord(false);
      }
   }
}
Beispiel #5
0
void ControlToolBar::OnRecord(wxCommandEvent &evt)
{
   if (gAudioIO->IsBusy()) {
      mRecord->PopUp();
      return;
   }
   AudacityProject *p = GetActiveProject();
   if (p && p->GetCleanSpeechMode()) {
      size_t numProjects = gAudacityProjects.Count();
      bool tracks = (p && !p->GetTracks()->IsEmpty());
      if (tracks || (numProjects > 1)) {
         wxMessageBox(_("Recording in CleanSpeech mode is not possible when a track, or more than one project, is already open."),
            _("Recording not permitted"),
            wxOK | wxICON_INFORMATION,
            this);
         mRecord->PopUp();
         mRecord->Disable();
         return;
      }
   }

   if( evt.GetInt() == 1 ) // used when called by keyboard shortcut. Default (0) ignored.
      mRecord->SetShift(true);
   if( evt.GetInt() == 2 )
      mRecord->SetShift(false);

   SetRecord(true);

   if (p) {
      TrackList *t = p->GetTracks();
      TrackListIterator it(t);
      if(it.First() == NULL)
         mRecord->SetShift(false);
      double t0 = p->GetSel0();
      double t1 = p->GetSel1();
      if (t1 == t0)
         t1 = 1000000000.0;     // record for a long, long time (tens of years)

      /* TODO: set up stereo tracks if that is how the user has set up
       * their preferences, and choose sample format based on prefs */
      WaveTrackArray newRecordingTracks, playbackTracks;
/* REQUIRES PORTMIDI */
//      NoteTrackArray midiTracks;

      bool duplex;
      gPrefs->Read(wxT("/AudioIO/Duplex"), &duplex, true);
            
      if(duplex){
         playbackTracks = t->GetWaveTrackArray(false);
/* REQUIRES PORTMIDI */
//		 midiTracks = t->GetNoteTrackArray(false);
     }
      else {
         playbackTracks = WaveTrackArray();
/* REQUIRES PORTMIDI */
//		 midiTracks = NoteTrackArray();
     }
      
      // If SHIFT key was down, the user wants append to tracks
      int recordingChannels = 0;
      bool shifted = mRecord->WasShiftDown();
      if (shifted) {
         TrackListIterator it(t);
         WaveTrack *wt;
         bool sel = false;
         double allt0 = t0;

         // Find the maximum end time of selected and all wave tracks
         for (Track *tt = it.First(); tt; tt = it.Next()) {
            if (tt->GetKind() == Track::Wave) {
               wt = (WaveTrack *)tt;
               if (wt->GetEndTime() > allt0) {
                  allt0 = wt->GetEndTime();
               }
            
               if (tt->GetSelected()) {
                  sel = true;
                  if (duplex)
                     playbackTracks.Remove(wt);
                  if (wt->GetEndTime() > t0) {
                     t0 = wt->GetEndTime();
                  }
               }
            }
         }

         // Use end time of all wave tracks if none selected
         if (!sel) {
            t0 = allt0;
         }

         // Pad selected/all wave tracks to make them all the same length
         for (Track *tt = it.First(); tt; tt = it.Next()) {
            if (tt->GetKind() == Track::Wave && (tt->GetSelected() || !sel)) {
               wt = (WaveTrack *)tt;
               t1 = wt->GetEndTime();
               if (t1 < t0) {
                  WaveTrack *newTrack = p->GetTrackFactory()->NewWaveTrack();
                  newTrack->InsertSilence(0.0, t0 - t1);
                  newTrack->Flush();
                  wt->Clear(t1, t0);
                  wt->Paste(t1, newTrack);
                  delete newTrack;
               }
               newRecordingTracks.Add(wt);
            }
         }

         t1 = 1000000000.0;     // record for a long, long time (tens of years)
      }
      else {
         recordingChannels = gPrefs->Read(wxT("/AudioIO/RecordChannels"), 2);
         for (int c = 0; c < recordingChannels; c++) {
            WaveTrack *newTrack = p->GetTrackFactory()->NewWaveTrack();

            int initialheight = newTrack->GetHeight();

            newTrack->SetOffset(t0);

            if (recordingChannels <= 2) {
               newTrack->SetHeight(initialheight/recordingChannels);
            }
            else {
               newTrack->SetMinimized(true);
            }

            if (recordingChannels == 2) {
               if (c == 0) {
                  newTrack->SetChannel(Track::LeftChannel);
                  newTrack->SetLinked(true);
               }
               else {
                  newTrack->SetChannel(Track::RightChannel);
                  newTrack->SetTeamed(true);
               }
            }
            else {
               newTrack->SetChannel( Track::MonoChannel );
            }

            newRecordingTracks.Add(newTrack);
         }
         
         // msmeyer: StartStream calls a callback which triggers auto-save, so
         // we add the tracks where recording is done into now. We remove them
         // later if starting the stream fails
         for (unsigned int i = 0; i < newRecordingTracks.GetCount(); i++)
            t->Add(newRecordingTracks[i]);
      }

      int token = gAudioIO->StartStream(playbackTracks,
                                        newRecordingTracks,
/* REQUIRES PORTMIDI */
//                                        midiTracks,
                                        t->GetTimeTrack(),
                                        p->GetRate(), t0, t1, p);

      bool success = (token != 0);
      
      if (success) {
         p->SetAudioIOToken(token);
         mBusyProject = p;
         SetVUMeters(p);
      }
      else {
         // msmeyer: Delete recently added tracks if opening stream fails
         if (!shifted) {
            for (unsigned int i = 0; i < newRecordingTracks.GetCount(); i++) {
               t->Remove(newRecordingTracks[i]);
               delete newRecordingTracks[i];
            }
         }

         // msmeyer: Show error message if stream could not be opened
         wxMessageBox(_("Error while opening sound device. "
            wxT("Please check the input device settings and the project sample rate.")),
                      _("Error"), wxOK | wxICON_EXCLAMATION, this);

         SetPlay(false);
         SetStop(false);
         SetRecord(false);
      }
   }
}