dsp.c

static int __ast_dsp_call_progress(struct ast_dsp *dsp, short *s, int len)
{
	int x;
	int y;
	int pass;
	int newstate = DSP_TONE_STATE_SILENCE;
	int res = 0;
	while(len) {
		/* Take the lesser of the number of samples we need and what we have */
		pass = len;
		if (pass > dsp->gsamp_size - dsp->gsamps) 
			pass = dsp->gsamp_size - dsp->gsamps;
		for (x=0;x<pass;x++) {
			for (y=0;y<dsp->freqcount;y++) 
				goertzel_sample(&dsp->freqs[y], s[x]);
			dsp->genergy += s[x] * s[x];
		}
		s += pass;
		dsp->gsamps += pass;
		len -= pass;
		if (dsp->gsamps == dsp->gsamp_size) {
			float hz[7];
			for (y=0;y<7;y++)
				hz[y] = goertzel_result(&dsp->freqs[y]);
#if 0
			printf("\n350:     425:     440:     480:     620:     950:     1400:    1800:    Energy:   \n");
			printf("%.2e %.2e %.2e %.2e %.2e %.2e %.2e %.2e %.2e\n", 
				hz[HZ_350], hz[HZ_425], hz[HZ_440], hz[HZ_480], hz[HZ_620], hz[HZ_950], hz[HZ_1400], hz[HZ_1800], dsp->genergy);
#endif
			switch(dsp->progmode) {
			case PROG_MODE_NA:
				if (pair_there(hz[HZ_480], hz[HZ_620], hz[HZ_350], hz[HZ_440], dsp->genergy)) {
					newstate = DSP_TONE_STATE_BUSY;
				} else if (pair_there(hz[HZ_440], hz[HZ_480], hz[HZ_350], hz[HZ_620], dsp->genergy)) {
					newstate = DSP_TONE_STATE_RINGING;
				} else if (pair_there(hz[HZ_350], hz[HZ_440], hz[HZ_480], hz[HZ_620], dsp->genergy)) {
					newstate = DSP_TONE_STATE_DIALTONE;
				} else if (hz[HZ_950] > TONE_MIN_THRESH * TONE_THRESH) {
					newstate = DSP_TONE_STATE_SPECIAL1;
				} else if (hz[HZ_1400] > TONE_MIN_THRESH * TONE_THRESH) {
					if (dsp->tstate == DSP_TONE_STATE_SPECIAL1)
						newstate = DSP_TONE_STATE_SPECIAL2;
				} else if (hz[HZ_1800] > TONE_MIN_THRESH * TONE_THRESH) {
					if (dsp->tstate == DSP_TONE_STATE_SPECIAL2)
						newstate = DSP_TONE_STATE_SPECIAL3;
				} else if (dsp->genergy > TONE_MIN_THRESH * TONE_THRESH) {
					newstate = DSP_TONE_STATE_TALKING;
				} else
					newstate = DSP_TONE_STATE_SILENCE;
				break;
			case PROG_MODE_CR:
				if (hz[HZ_425] > TONE_MIN_THRESH * TONE_THRESH) {
					newstate = DSP_TONE_STATE_RINGING;
				} else if (dsp->genergy > TONE_MIN_THRESH * TONE_THRESH) {
					newstate = DSP_TONE_STATE_TALKING;
				} else
					newstate = DSP_TONE_STATE_SILENCE;
				break;
			default:
				ast_log(LOG_WARNING, "Can't process in unknown prog mode '%d'\n", dsp->progmode);
			}
			if (newstate == dsp->tstate) {
				dsp->tcount++;
				if (dsp->tcount == COUNT_THRESH) {
					if ((dsp->features & DSP_PROGRESS_BUSY) && 
					    dsp->tstate == DSP_TONE_STATE_BUSY) {
						res = AST_CONTROL_BUSY;
						dsp->features &= ~DSP_FEATURE_CALL_PROGRESS;
					} else if ((dsp->features & DSP_PROGRESS_TALK) && 
						   dsp->tstate == DSP_TONE_STATE_TALKING) {
						res = AST_CONTROL_ANSWER;
						dsp->features &= ~DSP_FEATURE_CALL_PROGRESS;
					} else if ((dsp->features & DSP_PROGRESS_RINGING) && 
						   dsp->tstate == DSP_TONE_STATE_RINGING)
						res = AST_CONTROL_RINGING;
					else if ((dsp->features & DSP_PROGRESS_CONGESTION) && 
						 dsp->tstate == DSP_TONE_STATE_SPECIAL3) {
						res = AST_CONTROL_CONGESTION;
						dsp->features &= ~DSP_FEATURE_CALL_PROGRESS;
					}
				}
			} else {
#if 0
				printf("Newstate: %d\n", newstate);
#endif
				dsp->tstate = newstate;
				dsp->tcount = 1;
			}
			
			/* Reset goertzel */						
			for (x=0;x<7;x++)
				dsp->freqs[x].v2 = dsp->freqs[x].v3 = 0.0;
			dsp->gsamps = 0;
			dsp->genergy = 0.0;
		}
	}
#if 0
	if (res)
		printf("Returning %d\n", res);
#endif		
	return res;
}

int ast_dsp_call_progress(struct ast_dsp *dsp, struct ast_frame *inf)
{
	if (inf->frametype != AST_FRAME_VOICE) {
		ast_log(LOG_WARNING, "Can't check call progress of non-voice frames\n");
		return 0;
	}
	if (inf->subclass != AST_FORMAT_SLINEAR) {
		ast_log(LOG_WARNING, "Can only check call progress in signed-linear frames\n");
		return 0;
	}
	return __ast_dsp_call_progress(dsp, inf->data, inf->datalen / 2);
}

static int __ast_dsp_silence(struct ast_dsp *dsp, short *s, int len, int *totalsilence)
{
	int accum;
	int x;
	int res = 0;

	if (!len)
		return 0;
	accum = 0;
	for (x=0;x<len; x++) 
		accum += abs(s[x]);
	accum /= len;
	if (accum < dsp->threshold) {
		dsp->totalsilence += len/8;
		if (dsp->totalnoise) {
			/* Move and save history */
			memmove(dsp->historicnoise + DSP_HISTORY - dsp->busycount, dsp->historicnoise + DSP_HISTORY - dsp->busycount +1, dsp->busycount*sizeof(dsp->historicnoise[0]));
			dsp->historicnoise[DSP_HISTORY - 1] = dsp->totalnoise;
/* we don't want to check for busydetect that frequently */
#if 0
			dsp->busymaybe = 1;
#endif
		}
		dsp->totalnoise = 0;
		res = 1;
	} else {
		dsp->totalnoise += len/8;
		if (dsp->totalsilence) {
			int silence1 = dsp->historicsilence[DSP_HISTORY - 1];
			int silence2 = dsp->historicsilence[DSP_HISTORY - 2];
			/* Move and save history */
			memmove(dsp->historicsilence + DSP_HISTORY - dsp->busycount, dsp->historicsilence + DSP_HISTORY - dsp->busycount + 1, dsp->busycount*sizeof(dsp->historicsilence[0]));
			dsp->historicsilence[DSP_HISTORY - 1] = dsp->totalsilence;
			/* check if the previous sample differs only by BUSY_PERCENT from the one before it */
			if (silence1 < silence2) {
				if (silence1 + silence1/BUSY_PERCENT >= silence2)
					dsp->busymaybe = 1;
				else 
					dsp->busymaybe = 0;
			} else {
				if (silence1 - silence1/BUSY_PERCENT <= silence2)
					dsp->busymaybe = 1;
				else 
					dsp->busymaybe = 0;
			}
		}
		dsp->totalsilence = 0;
	}
	if (totalsilence)
		*totalsilence = dsp->totalsilence;
	return res;
}
#ifdef BUSYDETECT_MARTIN
int ast_dsp_busydetect(struct ast_dsp *dsp)
{
	int res = 0, x;
#ifndef BUSYDETECT_TONEONLY
	int avgsilence = 0, hitsilence = 0;
#endif
	int avgtone = 0, hittone = 0;
	if (!dsp->busymaybe)
		return res;
	for (x=DSP_HISTORY - dsp->busycount;x<DSP_HISTORY;x++) {
#ifndef BUSYDETECT_TONEONLY
		avgsilence += dsp->historicsilence[x];
#endif
		avgtone += dsp->historicnoise[x];
	}
#ifndef BUSYDETECT_TONEONLY
	avgsilence /= dsp->busycount;
#endif
	avgtone /= dsp->busycount;
	for (x=DSP_HISTORY - dsp->busycount;x<DSP_HISTORY;x++) {
#ifndef BUSYDETECT_TONEONLY
		if (avgsilence > dsp->historicsilence[x]) {
			if (avgsilence - (avgsilence / BUSY_PERCENT) <= dsp->historicsilence[x])
				hitsilence++;
		} else {
			if (avgsilence + (avgsilence / BUSY_PERCENT) >= dsp->historicsilence[x])
				hitsilence++;
		}
#endif
		if (avgtone > dsp->historicnoise[x]) {
			if (avgtone - (avgtone / BUSY_PERCENT) <= dsp->historicnoise[x])
				hittone++;
		} else {
			if (avgtone + (avgtone / BUSY_PERCENT) >= dsp->historicnoise[x])
				hittone++;
		}
	}
#ifndef BUSYDETECT_TONEONLY
	if ((hittone >= dsp->busycount - 1) && (hitsilence >= dsp->busycount - 1) && 
	    (avgtone >= BUSY_MIN && avgtone <= BUSY_MAX) && 
	    (avgsilence >= BUSY_MIN && avgsilence <= BUSY_MAX)) {
#else
	if ((hittone >= dsp->busycount - 1) && (avgtone >= BUSY_MIN && avgtone <= BUSY_MAX)) {
#endif
#ifdef BUSYDETECT_COMPARE_TONE_AND_SILENCE
#ifdef BUSYDETECT_TONEONLY
#error You cant use BUSYDETECT_TONEONLY together with BUSYDETECT_COMPARE_TONE_AND_SILENCE
#endif
		if (avgtone > avgsilence) {
			if (avgtone - avgtone/(BUSY_PERCENT*2) <= avgsilence)
				res = 1;
		} else {
			if (avgtone + avgtone/(BUSY_PERCENT*2) >= avgsilence)
				res = 1;
		}
#else
		res = 1;
#endif
	}
#if 0
	if (res)
		ast_log(LOG_NOTICE, "detected busy, avgtone: %d, avgsilence %d\n", avgtone, avgsilence);
#endif
	return res;
}
#endif

#ifdef BUSYDETECT
int ast_dsp_busydetect(struct ast_dsp *dsp)
{
	int x;
	int res = 0;
	int max, min;

#if 0
	if (dsp->busy_hits > 5);
	return 0;
#endif
	if (dsp->busymaybe) {
#if 0
		printf("Maybe busy!\n");
#endif		
		dsp->busymaybe = 0;
		min = 9999;
		max = 0;
		for (x=DSP_HISTORY - dsp->busycount;x<DSP_HISTORY;x++) {
#if 0
			printf("Silence: %d, Noise: %d\n", dsp->historicsilence[x], dsp->historicnoise[x]);
#endif			
			if (dsp->historicsilence[x] < min)
				min = dsp->historicsilence[x];
			if (dsp->historicnoise[x] < min)
				min = dsp->historicnoise[x];
			if (dsp->historicsilence[x] > max)
				max = dsp->historicsilence[x];
			if (dsp->historicnoise[x] > max)
				max = dsp->historicnoise[x];
		}
		if ((max - min < BUSY_THRESHOLD) && (max < BUSY_MAX) && (min > BUSY_MIN)) {
#if 0
			printf("Busy!\n");
#endif			
			res = 1;
		}
#if 0
		printf("Min: %d, max: %d\n", min, max);
#endif		
	}
	return res;
}
#endif

int ast_dsp_silence(struct ast_dsp *dsp, struct ast_frame *f, int *totalsilence)
{
	short *s;
	int len;
	
	if (f->frametype != AST_FRAME_VOICE) {
		ast_log(LOG_WARNING, "Can't calculate silence on a non-voice frame\n");
		return 0;
	}
	if (f->subclass != AST_FORMAT_SLINEAR) {
		ast_log(LOG_WARNING, "Can only calculate silence on signed-linear frames :(\n");
		return 0;
	}
	s = f->data;
	len = f->datalen/2;
	return __ast_dsp_silence(dsp, s, len, totalsilence);
}

struct ast_frame *ast_dsp_process(struct ast_channel *chan, struct ast_dsp *dsp, struct ast_frame *af)
{
	int silence;
	int res;
	int digit;
	int x;
	unsigned short *shortdata;
	unsigned char *odata;
	int len;
	int writeback = 0;

#define FIX_INF(inf) do { \
		if (writeback) { \
			switch(inf->subclass) { \
			case AST_FORMAT_SLINEAR: \
				break; \
			case AST_FORMAT_ULAW: \
				for (x=0;x<len;x++) \
					odata[x] = AST_LIN2MU(shortdata[x]); \
				break; \
			case AST_FORMAT_ALAW: \
				for (x=0;x<len;x++) \
					odata[x] = AST_LIN2A(shortdata[x]); \
				break; \
			} \
		} \
	} while(0) 

	if (!af)
		return NULL;
	if (af->frametype != AST_FRAME_VOICE)
		return af;
	odata = af->data;
	len = af->datalen;
	/* Make sure we have short data */
	switch(af->subclass) {
	case AST_FORMAT_SLINEAR:
		shortdata = af->data;
		len = af->datalen / 2;
		break;
	case AST_FORMAT_ULAW:
		shortdata = alloca(af->datalen * 2);
		if (!shortdata) {
			ast_log(LOG_WARNING, "Unable to allocate stack space for data: %s\n", strerror(errno));
			return af;
		}
		for (x=0;x<len;x++) 
			shortdata[x] = AST_MULAW(odata[x]);
		break;
	case AST_FORMAT_ALAW:
		shortdata = alloca(af->datalen * 2);
		if (!shortdata) {
			ast_log(LOG_WARNING, "Unable to allocate stack space for data: %s\n", strerror(errno));
			return af;
		}
		for (x=0;x<len;x++) 
			shortdata[x] = AST_ALAW(odata[x]);
		break;
	default:
		ast_log(LOG_WARNING, "Inband DTMF is not supported on codec %s. Use RFC2833\n", ast_getformatname(af->subclass));
		return af;
	}
	silence = __ast_dsp_silence(dsp, shortdata, len, NULL);
	if ((dsp->features & DSP_FEATURE_SILENCE_SUPPRESS) && silence) {
		memset(&dsp->f, 0, sizeof(dsp->f));
		dsp->f.frametype = AST_FRAME_NULL;
		return &dsp->f;
	}
	if ((dsp->features & DSP_FEATURE_BUSY_DETECT) && ast_dsp_busydetect(dsp)) {
		chan->_softhangup |= AST_SOFTHANGUP_DEV;
		memset(&dsp->f, 0, sizeof(dsp->f));
		dsp->f.frametype = AST_FRAME_CONTROL;
		dsp->f.subclass = AST_CONTROL_BUSY;
		ast_log(LOG_DEBUG, "Requesting Hangup because the busy tone was detected on channel %s\n", chan->name);
		return &dsp->f;
	}
	if ((dsp->features & DSP_FEATURE_DTMF_DETECT)) {
		digit = __ast_dsp_digitdetect(dsp, shortdata, len, &writeback);
#if 0
		if (digit)
			printf("Performing digit detection returned %d, digitmode is %d\n", digit, dsp->digitmode);
#endif			
		if (dsp->digitmode & (DSP_DIGITMODE_MUTECONF | DSP_DIGITMODE_MUTEMAX)) {
			if (!dsp->thinkdigit) {
				if (digit) {
					/* Looks like we might have something.  
					 * Request a conference mute for the moment */
					memset(&dsp->f, 0, sizeof(dsp->f));
					dsp->f.frametype = AST_FRAME_DTMF;
					dsp->f.subclass = 'm';
					dsp->thinkdigit = 'x';
					FIX_INF(af);
					if (chan)
						ast_queue_frame(chan, af);
					ast_frfree(af);
					return &dsp->f;
				}
			} else {
				if (digit) {
					/* Thought we saw one last time.  Pretty sure we really have now */
					if (dsp->thinkdigit) {
						if ((dsp->thinkdigit != 'x') && (dsp->thinkdigit != digit)) {
							/* If we found a digit, and we're changing digits, go
							   ahead and send this one, but DON'T stop confmute because
							   we're detecting something else, too... */
							memset(&dsp->f, 0, sizeof(dsp->f));
							dsp->f.frametype = AST_FRAME_DTMF;
							dsp->f.subclass = dsp->thinkdigit;
							FIX_INF(af);
							if (chan)
								ast_queue_frame(chan, af);
							ast_frfree(af);
						}
						dsp->thinkdigit = digit;
						return &dsp->f;
					}
					dsp->thinkdigit = digit;
				} else {
					if (dsp->thinkdigit) {
						memset(&dsp->f, 0, sizeof(dsp->f));
						if (dsp->thinkdigit != 'x') {
							/* If we found a digit, send it now */
							dsp->f.frametype = AST_FRAME_DTMF;
							dsp->f.subclass = dsp->thinkdigit;
							dsp->thinkdigit = 0;
						} else {
							dsp->f.frametype = AST_FRAME_DTMF;
							dsp->f.subclass = 'u';
							dsp->thinkdigit = 0;
						}
						FIX_INF(af);
						if (chan)
							ast_queue_frame(chan, af);
						ast_frfree(af);
						return &dsp->f;
					}
				}
			}
		} else if (!digit) {
			/* Only check when there is *not* a hit... */
			if (dsp->digitmode & DSP_DIGITMODE_MF) {
				if (dsp->td.mf.current_digits) {
					memset(&dsp->f, 0, sizeof(dsp->f));
					dsp->f.frametype = AST_FRAME_DTMF;
					dsp->f.subclass = dsp->td.mf.digits[0];
					memmove(dsp->td.mf.digits, dsp->td.mf.digits + 1, dsp->td.mf.current_digits);
					dsp->td.mf.current_digits--;
					FIX_INF(af);
					if (chan)
						ast_queue_frame(chan, af);
					ast_frfree(af);
					return &dsp->f;
				}
			} else {
				if (dsp->td.dtmf.current_digits) {
					memset(&dsp->f, 0, sizeof(dsp->f));
					dsp->f.frametype = AST_FRAME_DTMF;
					dsp->f.subclass = dsp->td.dtmf.digits[0];
					memmove(dsp->td.dtmf.digits, dsp->td.dtmf.digits + 1, dsp->td.dtmf.current_digits);
					dsp->td.dtmf.current_digits--;
					FIX_INF(af);
					if (chan)
						ast_queue_frame(chan, af);
					ast_frfree(af);
					return &dsp->f;
				}
			}
		}
	}
	if ((dsp->features & DSP_FEATURE_CALL_PROGRESS)) {
		res = __ast_dsp_call_progress(dsp, shortdata, len);
		if (res) {
			switch(res) {
			case AST_CONTROL_ANSWER:
			case AST_CONTROL_BUSY:
			case AST_CONTROL_RINGING:
			case AST_CONTROL_CONGESTION:
				memset(&dsp->f, 0, sizeof(dsp->f));
				dsp->f.frametype = AST_FRAME_CONTROL;
				dsp->f.subclass = res;
				dsp->f.src = "dsp_progress";
				if (chan) 
					ast_queue_frame(chan, &dsp->f);
				break;
			default:
				ast_log(LOG_WARNING, "Don't know how to represent call progress message %d\n", res);
			}
		}
	}
	FIX_INF(af);
	return af;
}

static void ast_dsp_prog_reset(struct ast_dsp *dsp)
{
	int max = 0;
	int x;
	
	dsp->gsamp_size = modes[dsp->progmode].size;
	dsp->gsamps = 0;
	for (x=0;x<sizeof(modes[dsp->progmode].freqs) / sizeof(modes[dsp->progmode].freqs[0]);x++) {
		if (modes[dsp->progmode].freqs[x]) {
			goertzel_init(&dsp->freqs[x], (float)modes[dsp->progmode].freqs[x], dsp->gsamp_size);
			max = x + 1;
		}
	}
	dsp->freqcount = max;
}

struct ast_dsp *ast_dsp_new(void)
{
	struct ast_dsp *dsp;

	dsp = malloc(sizeof(struct ast_dsp));
	if (dsp) {
		memset(dsp, 0, sizeof(struct ast_dsp));
		dsp->threshold = DEFAULT_THRESHOLD;
		dsp->features = DSP_FEATURE_SILENCE_SUPPRESS;
		dsp->busycount = DSP_HISTORY;
		/* Initialize DTMF detector */
		ast_dtmf_detect_init(&dsp->td.dtmf);
		/* Initialize initial DSP progress detect parameters */
		ast_dsp_prog_reset(dsp);
	}
	return dsp;
}

void ast_dsp_set_features(struct ast_dsp *dsp, int features)
{
	dsp->features = features;
}

void ast_dsp_free(struct ast_dsp *dsp)
{
	free(dsp);
}

void ast_dsp_set_threshold(struct ast_dsp *dsp, int threshold)
{
	dsp->threshold = threshold;
}

void ast_dsp_set_busy_count(struct ast_dsp *dsp, int cadences)
{
	if (cadences < 4)
		cadences = 4;
	if (cadences > DSP_HISTORY)
		cadences = DSP_HISTORY;
	dsp->busycount = cadences;
}

void ast_dsp_digitreset(struct ast_dsp *dsp)
{
	int i;
	
	dsp->thinkdigit = 0;
	if (dsp->digitmode & DSP_DIGITMODE_MF) {
		memset(dsp->td.mf.digits, 0, sizeof(dsp->td.mf.digits));
		dsp->td.mf.current_digits = 0;
		/* Reinitialise the detector for the next block */
		for (i = 0;  i < 6;  i++) {
			goertzel_reset(&dsp->td.mf.tone_out[i]);
#ifdef OLD_DSP_ROUTINES
			goertzel_reset(&dsp->td.mf.tone_out2nd[i]);
#endif			
		}
#ifdef OLD_DSP_ROUTINES
		dsp->td.mf.energy = 0.0;
		dsp->td.mf.hit1 = dsp->td.mf.hit2 = dsp->td.mf.hit3 = dsp->td.mf.hit4 = dsp->td.mf.mhit = 0;
#else
		dsp->td.mf.hits[4] = dsp->td.mf.hits[3] = dsp->td.mf.hits[2] = dsp->td.mf.hits[1] = dsp->td.mf.hits[0] = dsp->td.mf.mhit = 0;
#endif		
		dsp->td.mf.current_sample = 0;
	} else {
		memset(dsp->td.dtmf.digits, 0, sizeof(dsp->td.dtmf.digits));
		dsp->td.dtmf.current_digits = 0;
		/* Reinitialise the detector for the next block */
		for (i = 0;  i < 4;  i++) {
			goertzel_reset(&dsp->td.dtmf.row_out[i]);
			goertzel_reset(&dsp->td.dtmf.col_out[i]);
#ifdef OLD_DSP_ROUTINES
			goertzel_reset(&dsp->td.dtmf.row_out2nd[i]);
			goertzel_reset(&dsp->td.dtmf.col_out2nd[i]);
#endif			
		}
#ifdef FAX_DETECT
		goertzel_reset (&dsp->td.dtmf.fax_tone);
#endif
#ifdef OLD_DSP_ROUTINES
#ifdef FAX_DETECT
		goertzel_reset (&dsp->td.dtmf.fax_tone2nd);
#endif
		dsp->td.dtmf.hit1 = dsp->td.dtmf.hit2 = dsp->td.dtmf.hit3 = dsp->td.dtmf.hit4 = dsp->td.dtmf.mhit = 0;
#else
		dsp->td.dtmf.hits[2] = dsp->td.dtmf.hits[1] = dsp->td.dtmf.hits[0] =  dsp->td.dtmf.mhit = 0;
#endif		
		dsp->td.dtmf.energy = 0.0;
		dsp->td.dtmf.current_sample = 0;
	}
}

void ast_dsp_reset(struct ast_dsp *dsp)
{
	int x;
	
	dsp->totalsilence = 0;
	dsp->gsamps = 0;
	for (x=0;x<4;x++)
		dsp->freqs[x].v2 = dsp->freqs[x].v3 = 0.0;
	memset(dsp->historicsilence, 0, sizeof(dsp->historicsilence));
	memset(dsp->historicnoise, 0, sizeof(dsp->historicnoise));	
}

int ast_dsp_digitmode(struct ast_dsp *dsp, int digitmode)
{
	int new;
	int old;
	
	old = dsp->digitmode & (DSP_DIGITMODE_DTMF | DSP_DIGITMODE_MF | DSP_DIGITMODE_MUTECONF | DSP_DIGITMODE_MUTEMAX);
	new = digitmode & (DSP_DIGITMODE_DTMF | DSP_DIGITMODE_MF | DSP_DIGITMODE_MUTECONF | DSP_DIGITMODE_MUTEMAX);
	if (old != new) {
		/* Must initialize structures if switching from MF to DTMF or vice-versa */
		if (new & DSP_DIGITMODE_MF)
			ast_mf_detect_init(&dsp->td.mf);
		else
			ast_dtmf_detect_init(&dsp->td.dtmf);
	}
	dsp->digitmode = digitmode;
	return 0;
}

int ast_dsp_set_call_progress_zone(struct ast_dsp *dsp, char *zone)
{
	int x;
	
	for (x=0;x<sizeof(aliases) / sizeof(aliases[0]);x++) {
		if (!strcasecmp(aliases[x].name, zone)) {
			dsp->progmode = aliases[x].mode;
			ast_dsp_prog_reset(dsp);
			return 0;
		}
	}
	return -1;
}

int ast_dsp_get_tstate(struct ast_dsp *dsp) 
{
	return dsp->tstate;
}

int ast_dsp_get_tcount(struct ast_dsp *dsp) 
{
	return dsp->tcount;
}