libs/audiographer/audiographer/general/chunker.h

   1 #ifndef AUDIOGRAPHER_CHUNKER_H
   2 #define AUDIOGRAPHER_CHUNKER_H
   3
   4 #include "audiographer/flag_debuggable.h"
   5 #include "audiographer/sink.h"
   6 #include "audiographer/type_utils.h"
   7 #include "audiographer/utils/listed_source.h"
   8
   9 namespace AudioGrapher
  10 {
  11
  12 /// A class that chunks process cycles into equal sized frames
  13 template<typename T = DefaultSampleType>
  14 class Chunker
  15   : public ListedSource<T>
  16   , public Sink<T>
  17   , public FlagDebuggable<>
  18 {
  19   public:
  20         /** Constructs a new Chunker with a constant chunk size.
  21           * \n NOT RT safe
  22           */
  23         Chunker (framecnt_t chunk_size)
  24           : chunk_size (chunk_size)
  25           , position (0)
  26         {
  27                 buffer = new T[chunk_size];
  28                 add_supported_flag (ProcessContext<T>::EndOfInput);
  29         }
  30
  31         ~Chunker()
  32         {
  33                 delete [] buffer;
  34         }
  35
  36         /** Outputs data in \a context in chunks with the size specified in the constructor.
  37           * Note that some calls might not produce any output, while others may produce several.
  38           * \n RT safe
  39           */
  40         void process (ProcessContext<T> const & context)
  41         {
  42                 check_flags (*this, context);
  43
  44                 framecnt_t frames_left = context.frames();
  45                 framecnt_t input_position = 0;
  46
  47                 while (position + frames_left >= chunk_size) {
  48                         // Copy from context to buffer
  49                         framecnt_t const frames_to_copy = chunk_size - position;
  50                         TypeUtils<T>::copy (&context.data()[input_position], &buffer[position], frames_to_copy);
  51
  52                         // Output whole buffer
  53                         ProcessContext<T> c_out (context, buffer, chunk_size);
  54                         ListedSource<T>::output (c_out);
  55
  56                         // Update counters
  57                         position = 0;
  58                         input_position += frames_to_copy;
  59                         frames_left -= frames_to_copy;
  60                 }
  61
  62                 if (frames_left) {
  63                         // Copy the rest of the data
  64                         TypeUtils<T>::copy (&context.data()[input_position], &buffer[position], frames_left);
  65                         position += frames_left;
  66                 }
  67
  68                 if (context.has_flag (ProcessContext<T>::EndOfInput)) {
  69                         ProcessContext<T> c_out (context, buffer, position);
  70                         ListedSource<T>::output (c_out);
  71                 }
  72         }
  73         using Sink<T>::process;
  74
  75   private:
  76         framecnt_t chunk_size;
  77         framecnt_t position;
  78         T * buffer;
  79
  80 };
  81
  82 } // namespace
  83
  84 #endif // AUDIOGRAPHER_CHUNKER_H
  85