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asterisk
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Changed the dtmf detection to integer based goertzel algorithm.

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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@66471 65c4cc65-6c06-0410-ace0-fbb531ad65f3
1.6.0
Doug Bailey 19 years ago
parent ed4726769a
commit d3e9141345
1 changed files with 42 additions and 57 deletions
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99
main/dsp.c
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@ -186,14 +186,20 @@ enum gsamp_thresh {
#endif #endif
typedef struct { typedef struct {
float v2; int v2;
float v3; int v3;
float fac; int chunky;
int fac;
#ifndef OLD_DSP_ROUTINES #ifndef OLD_DSP_ROUTINES
int samples; int samples;
#endif #endif
} goertzel_state_t; } goertzel_state_t;
typedef struct {
int value;
int power;
} goertzel_result_t;
typedef struct typedef struct
{ {
goertzel_state_t row_out[4]; goertzel_state_t row_out[4];
@ -290,12 +296,19 @@ static char bell_mf_positions[] = "1247C-358A--69*---0B----#";
static inline void goertzel_sample(goertzel_state_t *s, short sample) static inline void goertzel_sample(goertzel_state_t *s, short sample)
{ {
float v1; int v1;
float fsamp = sample;
v1 = s->v2; v1 = s->v2;
s->v2 = s->v3; s->v2 = s->v3;
s->v3 = s->fac * s->v2 - v1 + fsamp;
s->v3 = (s->fac * s->v2) >> 15;
s->v3 = s->v3 - v1 + (sample >> s->chunky);
if (abs(s->v3) > 32768) {
s->chunky++;
s->v3 = s->v3 >> 1;
s->v2 = s->v2 >> 1;
v1 = v1 >> 1;
}
} }
static inline void goertzel_update(goertzel_state_t *s, short *samps, int count) static inline void goertzel_update(goertzel_state_t *s, short *samps, int count)
@ -309,13 +322,17 @@ static inline void goertzel_update(goertzel_state_t *s, short *samps, int count)
static inline float goertzel_result(goertzel_state_t *s) static inline float goertzel_result(goertzel_state_t *s)
{ {
return s->v3 * s->v3 + s->v2 * s->v2 - s->v2 * s->v3 * s->fac; goertzel_result_t r;
r.value = (s->v3 * s->v3) + (s->v2 * s->v2);
r.value -= ((s->v2 * s->v3) >> 15) * s->fac;
r.power = s->chunky * 2;
return (float)r.value * (float)(1 << r.power);
} }
static inline void goertzel_init(goertzel_state_t *s, float freq, int samples) static inline void goertzel_init(goertzel_state_t *s, float freq, int samples)
{ {
s->v2 = s->v3 = 0.0; s->v2 = s->v3 = s->chunky = 0.0;
s->fac = 2.0 * cos(2.0 * M_PI * (freq / 8000.0)); s->fac = (int)(32768.0 * 2.0 * cos(2.0 * M_PI * (freq / 8000.0)));
#ifndef OLD_DSP_ROUTINES #ifndef OLD_DSP_ROUTINES
s->samples = samples; s->samples = samples;
#endif #endif
@ -323,7 +340,7 @@ static inline void goertzel_init(goertzel_state_t *s, float freq, int samples)
static inline void goertzel_reset(goertzel_state_t *s) static inline void goertzel_reset(goertzel_state_t *s)
{ {
s->v2 = s->v3 = 0.0; s->v2 = s->v3 = s->chunky = 0.0;
} }
struct ast_dsp { struct ast_dsp {
@ -431,7 +448,6 @@ static int dtmf_detect (dtmf_detect_state_t *s, int16_t amp[], int samples,
#endif #endif
#endif /* FAX_DETECT */ #endif /* FAX_DETECT */
float famp; float famp;
float v1;
int i; int i;
int j; int j;
int sample; int sample;
@ -464,35 +480,17 @@ static int dtmf_detect (dtmf_detect_state_t *s, int16_t amp[], int samples,
s->energy += famp*famp; s->energy += famp*famp;
/* With GCC 2.95, the following unrolled code seems to take about 35% /* With GCC 2.95, the following unrolled code seems to take about 35%
(rough estimate) as long as a neat little 0-3 loop */ (rough estimate) as long as a neat little 0-3 loop */
v1 = s->row_out[0].v2; goertzel_sample(s->row_out, amp[j]);
s->row_out[0].v2 = s->row_out[0].v3; goertzel_sample(s->col_out, amp[j]);
s->row_out[0].v3 = s->row_out[0].fac*s->row_out[0].v2 - v1 + famp; goertzel_sample(s->row_out + 1, amp[j]);
v1 = s->col_out[0].v2; goertzel_sample(s->col_out + 1, amp[j]);
s->col_out[0].v2 = s->col_out[0].v3; goertzel_sample(s->row_out + 2, amp[j]);
s->col_out[0].v3 = s->col_out[0].fac*s->col_out[0].v2 - v1 + famp; goertzel_sample(s->col_out + 2, amp[j]);
v1 = s->row_out[1].v2; goertzel_sample(s->row_out + 3, amp[j]);
s->row_out[1].v2 = s->row_out[1].v3; goertzel_sample(s->col_out + 3, amp[j]);
s->row_out[1].v3 = s->row_out[1].fac*s->row_out[1].v2 - v1 + famp;
v1 = s->col_out[1].v2;
s->col_out[1].v2 = s->col_out[1].v3;
s->col_out[1].v3 = s->col_out[1].fac*s->col_out[1].v2 - v1 + famp;
v1 = s->row_out[2].v2;
s->row_out[2].v2 = s->row_out[2].v3;
s->row_out[2].v3 = s->row_out[2].fac*s->row_out[2].v2 - v1 + famp;
v1 = s->col_out[2].v2;
s->col_out[2].v2 = s->col_out[2].v3;
s->col_out[2].v3 = s->col_out[2].fac*s->col_out[2].v2 - v1 + famp;
v1 = s->row_out[3].v2;
s->row_out[3].v2 = s->row_out[3].v3;
s->row_out[3].v3 = s->row_out[3].fac*s->row_out[3].v2 - v1 + famp;
v1 = s->col_out[3].v2;
s->col_out[3].v2 = s->col_out[3].v3;
s->col_out[3].v3 = s->col_out[3].fac*s->col_out[3].v2 - v1 + famp;
#ifdef FAX_DETECT #ifdef FAX_DETECT
/* Update fax tone */ /* Update fax tone */
v1 = s->fax_tone.v2; goertzel_sample(&s->fax_tone, amp[j]);
s->fax_tone.v2 = s->fax_tone.v3;
s->fax_tone.v3 = s->fax_tone.fac*s->fax_tone.v2 - v1 + famp;
#endif /* FAX_DETECT */ #endif /* FAX_DETECT */
#ifdef OLD_DSP_ROUTINES #ifdef OLD_DSP_ROUTINES
v1 = s->col_out2nd[0].v2; v1 = s->col_out2nd[0].v2;
@ -705,7 +703,6 @@ static int mf_detect (mf_detect_state_t *s, int16_t amp[],
int second_best; int second_best;
#endif #endif
float famp; float famp;
float v1;
int i; int i;
int j; int j;
int sample; int sample;
@ -738,24 +735,12 @@ static int mf_detect (mf_detect_state_t *s, int16_t amp[],
#endif #endif
/* With GCC 2.95, the following unrolled code seems to take about 35% /* With GCC 2.95, the following unrolled code seems to take about 35%
(rough estimate) as long as a neat little 0-3 loop */ (rough estimate) as long as a neat little 0-3 loop */
v1 = s->tone_out[0].v2; goertzel_sample(s->tone_out, amp[j]);
s->tone_out[0].v2 = s->tone_out[0].v3; goertzel_sample(s->tone_out + 1, amp[j]);
s->tone_out[0].v3 = s->tone_out[0].fac*s->tone_out[0].v2 - v1 + famp; goertzel_sample(s->tone_out + 2, amp[j]);
v1 = s->tone_out[1].v2; goertzel_sample(s->tone_out + 3, amp[j]);
s->tone_out[1].v2 = s->tone_out[1].v3; goertzel_sample(s->tone_out + 4, amp[j]);
s->tone_out[1].v3 = s->tone_out[1].fac*s->tone_out[1].v2 - v1 + famp; goertzel_sample(s->tone_out + 5, amp[j]);
v1 = s->tone_out[2].v2;
s->tone_out[2].v2 = s->tone_out[2].v3;
s->tone_out[2].v3 = s->tone_out[2].fac*s->tone_out[2].v2 - v1 + famp;
v1 = s->tone_out[3].v2;
s->tone_out[3].v2 = s->tone_out[3].v3;
s->tone_out[3].v3 = s->tone_out[3].fac*s->tone_out[3].v2 - v1 + famp;
v1 = s->tone_out[4].v2;
s->tone_out[4].v2 = s->tone_out[4].v3;
s->tone_out[4].v3 = s->tone_out[4].fac*s->tone_out[4].v2 - v1 + famp;
v1 = s->tone_out[5].v2;
s->tone_out[5].v2 = s->tone_out[5].v3;
s->tone_out[5].v3 = s->tone_out[5].fac*s->tone_out[5].v2 - v1 + famp;
#ifdef OLD_DSP_ROUTINES #ifdef OLD_DSP_ROUTINES
v1 = s->tone_out2nd[0].v2; v1 = s->tone_out2nd[0].v2;
s->tone_out2nd[0].v2 = s->tone_out2nd[0].v3; s->tone_out2nd[0].v2 = s->tone_out2nd[0].v3;

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