1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
|
#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_SCALE2D_SECOND 1.224744871f /* sqrt(1.5) */
#define XYZ_SCALE2D_SECOND 1.0f
#define W_SCALE2D_THIRD 1.414213562f /* sqrt(2) */
#define XYZ_SCALE2D_THIRD 1.082392196f
/* These are the necessary scales for first-order HF responses to play over
* higher-order 3D (periphonic) decoders.
*/
#define W_SCALE3D_SECOND 1.341640787f /* sqrt(1.8) */
#define XYZ_SCALE3D_SECOND 1.0f
#define W_SCALE3D_THIRD 1.695486018f
#define XYZ_SCALE3D_THIRD 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 freq_mult);
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 freq_mult);
void splitterap_clear(SplitterAllpass *splitter);
void splitterap_process(SplitterAllpass *splitter, ALfloat *restrict samples, ALsizei count);
#endif /* BFORMATDEC_H */
|
