Alc/hrtf.h

   1 #ifndef ALC_HRTF_H
   2 #define ALC_HRTF_H
   3
   4 #include "AL/al.h"
   5 #include "AL/alc.h"
   6
   7 #include "alMain.h"
   8 #include "alstring.h"
   9
  10
  11 struct Hrtf {
  12     ALuint sampleRate;
  13     ALsizei irSize;
  14     ALubyte evCount;
  15
  16     const ALubyte *azCount;
  17     const ALushort *evOffset;
  18     const ALshort *coeffs;
  19     const ALubyte *delays;
  20
  21     const char *filename;
  22     struct Hrtf *next;
  23 };
  24
  25 #define HRTFDELAY_BITS    (20)
  26 #define HRTFDELAY_FRACONE (1<<HRTFDELAY_BITS)
  27 #define HRTFDELAY_MASK    (HRTFDELAY_FRACONE-1)
  28
  29 /* The maximum number of virtual speakers used to generate HRTF coefficients
  30  * for decoding B-Format.
  31  */
  32 #define HRTF_AMBI_MAX_CHANNELS 16
  33
  34 void FreeHrtfs(void);
  35
  36 vector_HrtfEntry EnumerateHrtf(const_al_string devname);
  37 void FreeHrtfList(vector_HrtfEntry *list);
  38
  39 void GetHrtfCoeffs(const struct Hrtf *Hrtf, ALfloat elevation, ALfloat azimuth, ALfloat spread, ALfloat gain, ALfloat (*coeffs)[2], ALsizei *delays);
  40
  41 /**
  42  * Produces HRTF filter coefficients for decoding B-Format, given a set of
  43  * virtual speaker positions and HF/LF matrices for decoding to them. The
  44  * returned coefficients are ordered and scaled according to the matrices.
  45  * Returns the maximum impulse-response length of the generated coefficients.
  46  */
  47 ALsizei BuildBFormatHrtf(const struct Hrtf *Hrtf, ALfloat (*coeffs)[HRIR_LENGTH][2], ALsizei NumChannels, const ALfloat (*restrict AmbiPoints)[2], const ALfloat (*restrict AmbiMatrix)[2][MAX_AMBI_COEFFS], ALsizei AmbiCount);
  48
  49 #endif /* ALC_HRTF_H */