libs/audiographer/audiographer/general/sr_converter.h

   1 #ifndef AUDIOGRAPHER_SR_CONVERTER_H
   2 #define AUDIOGRAPHER_SR_CONVERTER_H
   3
   4 #include <samplerate.h>
   5
   6 #include "audiographer/visibility.h"
   7 #include "audiographer/flag_debuggable.h"
   8 #include "audiographer/sink.h"
   9 #include "audiographer/throwing.h"
  10 #include "audiographer/types.h"
  11 #include "audiographer/utils/listed_source.h"
  12
  13 namespace AudioGrapher
  14 {
  15
  16 /// Samplerate converter
  17 class LIBAUDIOGRAPHER_API SampleRateConverter
  18   : public ListedSource<float>
  19   , public Sink<float>
  20   , public FlagDebuggable<>
  21   , public Throwing<>
  22 {
  23   public:
  24         /// Constructor. \n RT safe
  25         SampleRateConverter (uint32_t channels);
  26         ~SampleRateConverter ();
  27
  28         /// Init converter \n Not RT safe
  29         void init (samplecnt_t in_rate, samplecnt_t out_rate, int quality = 0);
  30
  31         /// Returns max amount of samples that will be output \n RT safe
  32         samplecnt_t allocate_buffers (samplecnt_t max_samples);
  33
  34         /** Does sample rate conversion.
  35           * Note that outpt size may vary a lot.
  36           * May or may not output several contexts of data.
  37           * \n Should be RT safe.
  38           * \TODO Check RT safety from libsamplerate
  39           */
  40         void process (ProcessContext<float> const & c);
  41         using Sink<float>::process;
  42
  43   private:
  44
  45         void set_end_of_input (ProcessContext<float> const & c);
  46         void reset ();
  47
  48         bool           active;
  49         uint32_t       channels;
  50         samplecnt_t     max_samples_in;
  51
  52         float *        leftover_data;
  53         samplecnt_t     leftover_samples;
  54         samplecnt_t     max_leftover_samples;
  55
  56         float *        data_out;
  57         samplecnt_t     data_out_size;
  58
  59         SRC_DATA       src_data;
  60         SRC_STATE*     src_state;
  61 };
  62
  63 } // namespace
  64
  65 #endif // AUDIOGRAPHER_SR_CONVERTER_H