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#ifndef BFORMATDEC_H
#define BFORMATDEC_H
#include "alMain.h"
/* These are the necessary scales for first-order HF responses to play over
* higher-order 2D (non-periphonic) decoders.
*/
#define W_SCALE_2H0P 1.224744871f /* sqrt(1.5) */
#define XYZ_SCALE_2H0P 1.0f
#define W_SCALE_3H0P 1.414213562f /* sqrt(2) */
#define XYZ_SCALE_3H0P 1.082392196f
/* These are the necessary scales for first-order HF responses to play over
* higher-order 3D (periphonic) decoders.
*/
#define W_SCALE_2H2P 1.341640787f /* sqrt(1.8) */
#define XYZ_SCALE_2H2P 1.0f
#define W_SCALE_3H3P 1.695486018f
#define XYZ_SCALE_3H3P 1.136697713f
struct AmbDecConf;
struct BFormatDec;
struct AmbiUpsampler;
struct BFormatDec *bformatdec_alloc();
void bformatdec_free(struct BFormatDec **dec);
void bformatdec_reset(struct BFormatDec *dec, const struct AmbDecConf *conf, ALsizei chancount, ALuint srate, const ALsizei chanmap[MAX_OUTPUT_CHANNELS]);
/* Decodes the ambisonic input to the given output channels. */
void bformatdec_process(struct BFormatDec *dec, ALfloat (*restrict OutBuffer)[BUFFERSIZE], ALsizei OutChannels, const ALfloat (*restrict InSamples)[BUFFERSIZE], ALsizei SamplesToDo);
/* Up-samples a first-order input to the decoder's configuration. */
void bformatdec_upSample(struct BFormatDec *dec, ALfloat (*restrict OutBuffer)[BUFFERSIZE], const ALfloat (*restrict InSamples)[BUFFERSIZE], ALsizei InChannels, ALsizei SamplesToDo);
/* Stand-alone first-order upsampler. Kept here because it shares some stuff
* with bformatdec.
*/
struct AmbiUpsampler *ambiup_alloc();
void ambiup_free(struct AmbiUpsampler **ambiup);
void ambiup_reset(struct AmbiUpsampler *ambiup, const ALCdevice *device);
void ambiup_process(struct AmbiUpsampler *ambiup, ALfloat (*restrict OutBuffer)[BUFFERSIZE], ALsizei OutChannels, const ALfloat (*restrict InSamples)[BUFFERSIZE], ALsizei SamplesToDo);
/* Band splitter. Splits a signal into two phase-matching frequency bands. */
typedef struct BandSplitter {
ALfloat coeff;
ALfloat lp_z1;
ALfloat lp_z2;
ALfloat hp_z1;
} BandSplitter;
void bandsplit_init(BandSplitter *splitter, ALfloat f0norm);
void bandsplit_clear(BandSplitter *splitter);
void bandsplit_process(BandSplitter *splitter, ALfloat *restrict hpout, ALfloat *restrict lpout,
const ALfloat *input, ALsizei count);
/* The all-pass portion of the band splitter. Applies the same phase shift
* without splitting the signal.
*/
typedef struct SplitterAllpass {
ALfloat coeff;
ALfloat z1;
} SplitterAllpass;
void splitterap_init(SplitterAllpass *splitter, ALfloat f0norm);
void splitterap_clear(SplitterAllpass *splitter);
void splitterap_process(SplitterAllpass *splitter, ALfloat *restrict samples, ALsizei count);
typedef struct FrontStablizer {
SplitterAllpass APFilter[MAX_OUTPUT_CHANNELS];
BandSplitter LFilter, RFilter;
alignas(16) ALfloat LSplit[2][BUFFERSIZE];
alignas(16) ALfloat RSplit[2][BUFFERSIZE];
} FrontStablizer;
#endif /* BFORMATDEC_H */
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