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