libs/audiographer/audiographer/sndfile/sndfile_writer.h

   1 #ifndef AUDIOGRAPHER_SNDFILE_WRITER_H
   2 #define AUDIOGRAPHER_SNDFILE_WRITER_H
   3
   4 #include <boost/signals2.hpp>
   5 #include <boost/format.hpp>
   6 #include <string>
   7
   8 #include "audiographer/flag_debuggable.h"
   9 #include "audiographer/sink.h"
  10 #include "audiographer/types.h"
  11 #include "audiographer/sndfile/sndfile_base.h"
  12
  13 #include "pbd/signals.h"
  14
  15 namespace AudioGrapher
  16 {
  17
  18 /** Writer for audio files using libsndfile.
  19   * Only short, int and float are valid template parameters
  20   */
  21 template <typename T = DefaultSampleType>
  22 class SndfileWriter
  23   : public virtual SndfileBase
  24   , public Sink<T>
  25   , public Throwing<>
  26   , public FlagDebuggable<>
  27 {
  28   public:
  29         SndfileWriter (std::string const & path, int format, ChannelCount channels, nframes_t samplerate)
  30           : SndfileHandle (path, Write, format, channels, samplerate)
  31           , path (path)
  32         {
  33                 add_supported_flag (ProcessContext<T>::EndOfInput);
  34         }
  35
  36         virtual ~SndfileWriter () {}
  37
  38         SndfileWriter (SndfileWriter const & other) : SndfileHandle (other) {}
  39         using SndfileHandle::operator=;
  40
  41         /// Writes data to file
  42         void process (ProcessContext<T> const & c)
  43         {
  44                 check_flags (*this, c);
  45
  46                 if (throw_level (ThrowStrict) && c.channels() != channels()) {
  47                         throw Exception (*this, boost::str (boost::format
  48                                 ("Wrong number of channels given to process(), %1% instead of %2%")
  49                                 % c.channels() % channels()));
  50                 }
  51
  52                 nframes_t written = write (c.data(), c.frames());
  53                 if (throw_level (ThrowProcess) && written != c.frames()) {
  54                         throw Exception (*this, boost::str (boost::format
  55                                 ("Could not write data to output file (%1%)")
  56                                 % strError()));
  57                 }
  58
  59                 if (c.has_flag(ProcessContext<T>::EndOfInput)) {
  60                         writeSync();
  61                         FileWritten (path);
  62                 }
  63         }
  64
  65         using Sink<T>::process;
  66
  67         PBD::Signal1<void, std::string> FileWritten;
  68
  69   protected:
  70         /// SndfileHandle has to be constructed directly by deriving classes
  71         SndfileWriter ()
  72         {
  73                 add_supported_flag (ProcessContext<T>::EndOfInput);
  74         }
  75
  76   protected:
  77         std::string path;
  78 };
  79
  80 } // namespace
  81
  82 #endif // AUDIOGRAPHER_SNDFILE_WRITER_H