audacity/src/export/ExportCL.cpp

/**********************************************************************

  Audacity: A Digital Audio Editor

  ExportCL.cpp

  Joshua Haberman

  This code allows Audacity to export data by piping it to an external
  program. Although it could in theory be made to work on Windows
  (and perhaps even Mac), it's not worth it to invest the effort because
  commandline encoders are rarely installed there.

**********************************************************************/

#include "../Audacity.h"

#include <wx/button.h>
#include <wx/log.h>
#include <wx/process.h>
#include <wx/textctrl.h>

#include "Export.h"

#include "../Project.h"
#include "../Mix.h"
#include "../Prefs.h"
#include "../Internat.h"
#include "../float_cast.h"

//----------------------------------------------------------------------------
// ExportCLOptions
//----------------------------------------------------------------------------

class ExportCLOptions : public wxDialog
{
public:

   ExportCLOptions(wxWindow *parent);
   void PopulateOrExchange(ShuttleGui & S);
   void OnOK(wxCommandEvent & event);

private:

   DECLARE_EVENT_TABLE()
};

BEGIN_EVENT_TABLE(ExportCLOptions, wxDialog)
   EVT_BUTTON(wxID_OK, ExportCLOptions::OnOK)
END_EVENT_TABLE()

/// 
/// 
ExportCLOptions::ExportCLOptions(wxWindow *parent)
:  wxDialog(parent, wxID_ANY,
            wxString(_("Specify Command Line Encoder")))
{
   ShuttleGui S(this, eIsCreatingFromPrefs);

   PopulateOrExchange(S);
}

/// 
/// 
void ExportCLOptions::PopulateOrExchange(ShuttleGui & S)
{
   S.StartHorizontalLay(wxEXPAND, 0);
   {
      S.StartStatic(_("Command Line Export Setup"), true);
      {
         S.StartMultiColumn(2, wxEXPAND);
         {
            S.SetStretchyCol(1);
            S.TieTextBox(_("Command:"),
                         wxT("/FileFormats/ExternalProgramExportCommand"),
                         wxT("lame - \"%f\""),
                         64);
            S.AddFixedText(wxT(""));
            S.TieCheckBox(_("Show output"),
                          wxT("/FileFormats/ExternalProgramShowOutput"),
                          false);
         }
         S.EndMultiColumn();


         S.AddFixedText(_("Data will be piped to standard in. \"%f\" uses the file name in the export window."));
      }
      S.EndStatic();
   }
   S.EndHorizontalLay();

   S.AddStandardButtons();

   Layout();
   Fit();
   SetMinSize(GetSize());
   Center();

   return;
}

/// 
/// 
void ExportCLOptions::OnOK(wxCommandEvent& event)
{
   ShuttleGui S(this, eIsSavingToPrefs);
   PopulateOrExchange(S);

   EndModal(wxID_OK);

   return;
}

//----------------------------------------------------------------------------
// ExportCLProcess
//----------------------------------------------------------------------------

static void Drain(wxInputStream *s, wxString *o)
{
   while (s->CanRead()) {
      char buffer[4096];

      s->Read(buffer, WXSIZEOF(buffer) - 1);
      buffer[s->LastRead()] = wxT('\0');
      *o += LAT1CTOWX(buffer);
   }
}

class ExportCLProcess : public wxProcess
{
public:
   ExportCLProcess(wxString *output)
   {
      mOutput = output;
      mActive = true;
      mStatus = -555;
      Redirect();
   }

   bool IsActive()
   {
      return mActive;
   }

   void OnTerminate(int WXUNUSED( pid ), int status)
   {
      Drain(GetInputStream(), mOutput);
      Drain(GetErrorStream(), mOutput);

      mStatus = status;
      mActive = false;
   }

   int GetStatus()
   {
      return mStatus;
   }

private:
   wxString *mOutput;
   bool mActive;
   int mStatus;
};

//----------------------------------------------------------------------------
// ExportCL
//----------------------------------------------------------------------------

/* this structure combines the RIFF header, the format chunk, and the data
 * chunk header */
struct wav_header {
   /* RIFF header */
   char riffID[4];            /* "RIFF" */
   wxUint32 lenAfterRiff;     /* basically the file len - 8, or samples len + 32 */
   char riffType[4];          /* "WAVE" */
   
   /* format chunk */
   char fmtID[4];             /* "fmt " */
   wxUint32 formatChunkLen;   /* (format chunk len - first two fields) 16 in our case */
   wxUint16 formatTag;        /* 1 for PCM */
   wxUint16 channels;
   wxUint32 sampleRate;
   wxUint32 avgBytesPerSec;   /* sampleRate * blockAlign */
   wxUint16 blockAlign;       /* bitsPerSample * channels (assume bps % 8 = 0) */
   wxUint16 bitsPerSample;

   /* data chunk header */
   char dataID[4];            /* "data" */
   wxUint32 dataLen;          /* length of all samples in bytes */
};

class ExportCL : public ExportPlugin
{
public:

   ExportCL();
   void Destroy();

   // Required

   bool DisplayOptions(wxWindow *parent, int format = 0);
   int Export(AudacityProject *project,
               int channels,
               wxString fName,
               bool selectedOnly,
               double t0,
               double t1,
               MixerSpec *mixerSpec = NULL,
               Tags *metadata = NULL,
               int subformat = 0);
};

ExportCL::ExportCL()
:  ExportPlugin()
{
   AddFormat();
   SetFormat(wxT("CL"),0);
   AddExtension(wxT(""),0);
   SetMaxChannels(255,0);
   SetCanMetaData(false,0);
   SetDescription(_("(external program)"),0);
}

void ExportCL::Destroy()
{
   delete this;
}

int ExportCL::Export(AudacityProject *project,
                      int channels,
                      wxString fName,
                      bool selectionOnly,
                      double t0,
                      double t1, 
                      MixerSpec *mixerSpec,
                      Tags *metadata,
                      int subformat)
{
   ExportCLProcess *p;
   wxString output;
   wxString cmd;
   bool show;
   long rc;

   // Retrieve settings
   gPrefs->Read(wxT("/FileFormats/ExternalProgramShowOutput"), &show, false);
   cmd = gPrefs->Read(wxT("/FileFormats/ExternalProgramExportCommand"), wxT("lame - \"%f.mp3\""));
   cmd.Replace(wxT("%f"), fName);

#if defined(__WXMSW__)
   // Give Windows a chance at finding lame command in the default location.
   wxString paths[] = {wxT("HKEY_LOCAL_MACHINE\\Software\\Lame for Audacity"),
                       wxT("HKEY_LOCAL_MACHINE\\Software\\FFmpeg for Audacity")};
   wxString opath;
   wxString npath;
   wxRegKey reg;

   wxGetEnv(wxT("PATH"), &opath);
   npath = opath;

   for (int i = 0; i < WXSIZEOF(paths); i++) {
      reg.SetName(paths[i]);

      if (reg.Exists()) {
         wxString ipath;
         reg.QueryValue(wxT("InstallPath"), ipath);
         if (!ipath.IsEmpty()) {
            npath += wxPATH_SEP + ipath;
         }
      }
   }

   wxSetEnv(wxT("PATH"),npath.c_str());
#endif

   // Kick off the command
   p = new ExportCLProcess(&output);
   rc = wxExecute(cmd, wxEXEC_ASYNC, p);

#if defined(__WXMSW__)
   if (!opath.IsEmpty()) {
      wxSetEnv(wxT("PATH"),opath.c_str());
   }
#endif

   if (!rc) {
      wxMessageBox(wxString::Format(_("Cannot export audio to %s"),
                                    fName.c_str()));
      p->Detach();
      p->CloseOutput();
      return false;
   }

   // Turn off logging to prevent broken pipe messages
   wxLogNull nolog;

   // establish parameters
   int rate = lrint(project->GetRate());
   sampleCount maxBlockLen = 44100 * 5;
   unsigned long totalSamples = lrint((t1 - t0) * rate);
   unsigned long sampleBytes = totalSamples * channels * SAMPLE_SIZE(int16Sample);

   // fill up the wav header
   wav_header header;
   header.riffID[0]        = 'R';
   header.riffID[1]        = 'I';
   header.riffID[2]        = 'F';
   header.riffID[3]        = 'F';
   header.riffType[0]      = 'W';
   header.riffType[1]      = 'A';
   header.riffType[2]      = 'V';
   header.riffType[3]      = 'E';
   header.lenAfterRiff     = wxUINT32_SWAP_ON_BE(sampleBytes + 32);

   header.fmtID[0]         = 'f';
   header.fmtID[1]         = 'm';
   header.fmtID[2]         = 't';
   header.fmtID[3]         = ' ';
   header.formatChunkLen   = wxUINT32_SWAP_ON_BE(16);
   header.formatTag        = wxUINT16_SWAP_ON_BE(1);
   header.channels         = wxUINT16_SWAP_ON_BE(channels);
   header.sampleRate       = wxUINT32_SWAP_ON_BE(rate);
   header.bitsPerSample    = wxUINT16_SWAP_ON_BE(SAMPLE_SIZE(int16Sample) * 8);
   header.blockAlign       = wxUINT16_SWAP_ON_BE(header.bitsPerSample * header.channels);
   header.avgBytesPerSec   = wxUINT32_SWAP_ON_BE(header.sampleRate * header.blockAlign);
   header.dataID[0]        = 'd';
   header.dataID[1]        = 'a';
   header.dataID[2]        = 't';
   header.dataID[3]        = 'a';
   header.dataLen          = wxUINT32_SWAP_ON_BE(sampleBytes);

   // write the header
   wxOutputStream *os = p->GetOutputStream();
   os->Write(&header, sizeof(wav_header));

   // Mix 'em up
   int numWaveTracks;
   WaveTrack **waveTracks;
   TrackList *tracks = project->GetTracks();
   tracks->GetWaveTracks(selectionOnly, &numWaveTracks, &waveTracks);
   Mixer *mixer = CreateMixer(numWaveTracks,
                            waveTracks,
                            tracks->GetTimeTrack(),
                            t0,
                            t1,
                            channels,
                            maxBlockLen,
                            true,
                            rate,
                            int16Sample,
                            true,
                            mixerSpec);

   size_t numBytes = 0;
   samplePtr mixed;
   int updateResult = eProgressSuccess;

   // Prepare the progress display
   ProgressDialog *progress = new ProgressDialog(_("Export"),
      selectionOnly ?
      _("Exporting the selected audio using command-line encoder") :
   _("Exporting the entire project using command-line encoder"));

   // Start piping the mixed data to the command
   while (updateResult == eProgressSuccess && p->IsActive() && os->IsOk()) {
      // Capture any stdout and stderr from the command
      Drain(p->GetInputStream(), &output);
      Drain(p->GetErrorStream(), &output);

      // Need to mix another block
      if (numBytes == 0) {
         sampleCount numSamples = mixer->Process(maxBlockLen);
         if (numSamples == 0) {
            break;
         }
         
         mixed = mixer->GetBuffer();
         numBytes = numSamples * channels;

         // Byte-swapping is neccesary on big-endian machines, since
         // WAV files are little-endian
#if wxBYTE_ORDER == wxBIG_ENDIAN
         wxUint16 *buffer = (wxUint16 *) mixed;
         for (int i = 0; i < numBytes; i++) {
            buffer[i] = wxUINT16_SWAP_ON_BE(buffer[i]);
         }
#endif
         numBytes *= SAMPLE_SIZE(int16Sample);
      }

      // Don't write too much at once...pipes may not be able to handle it
      size_t bytes = wxMin(numBytes, 4096);
      numBytes -= bytes;

      while (bytes > 0) {
         os->Write(mixed, bytes);
         if (!os->IsOk()) {
            break;
         }
         bytes -= os->LastWrite();
         mixed += os->LastWrite();
      }

      // Update the progress display
      updateResult = progress->Update(mixer->MixGetCurrentTime()-t0, t1-t0);
   }

   // Done with the progress display
   delete progress;

   // Should make the process die
   p->CloseOutput();

   // Wait for process to terminate
   while (p->IsActive()) {
      wxMilliSleep(10);
      wxTheApp->Yield();
   }

   // Display output on error or if the user wants to see it
   if (p->GetStatus() != 0 || show) {
      // TODO use ShowInfoDialog() instead.
      wxDialog dlg(NULL,
                   wxID_ANY,
                   wxString(_("Command Output")),
                   wxDefaultPosition,
                   wxSize(600, 400),
                   wxDEFAULT_DIALOG_STYLE | wxRESIZE_BORDER);

      ShuttleGui S(&dlg, eIsCreating);
      S.AddTextWindow(output);
      S.StartHorizontalLay(wxALIGN_CENTER, false);
      {
         S.Id(wxID_OK).AddButton(_("&OK"))->SetDefault();
      }
      dlg.GetSizer()->AddSpacer(5);
      dlg.Layout();
      dlg.SetMinSize(dlg.GetSize());
      dlg.Center();

      dlg.ShowModal();
   }

   // Clean up
   delete mixer;
   delete[] waveTracks;                            
   delete p;

   return updateResult;
}

bool ExportCL::DisplayOptions(wxWindow *parent, int format)
{
   ExportCLOptions od(parent);

   od.ShowModal();

   return true;
}

//----------------------------------------------------------------------------
// Constructor
//----------------------------------------------------------------------------
ExportPlugin *New_ExportCL()
{
   return new ExportCL();
}

// Indentation settings for Vim and Emacs and unique identifier for Arch, a
// version control system. Please do not modify past this point.
//
// Local Variables:
// c-basic-offset: 3
// indent-tabs-mode: nil
// End:
//
// vim: et sts=3 sw=3
// arch-tag: c1578868-82c5-4f4a-b61b-8d82536a3141