session-ios/Libraries/spandsp/spandsp/time_scale.c
Frederic Jacobs 5b53e33cca Revert "Updating to spandsp-0.0.6"
This reverts commit ecea5d6e53.
//FREEBIE
2014-08-10 03:07:21 +02:00

301 lines
8.8 KiB
C

/*
* SpanDSP - a series of DSP components for telephony
*
* time_scale.c - Time scaling for linear speech data
*
* Written by Steve Underwood <steveu@coppice.org>
*
* Copyright (C) 2004 Steve Underwood
*
* All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License version 2.1,
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
* $Id: time_scale.c,v 1.30 2009/02/10 13:06:47 steveu Exp $
*/
/*! \file */
#if defined(HAVE_CONFIG_H)
#include "config.h"
#endif
#include <stdlib.h>
#include <stdio.h>
#include <inttypes.h>
#include <string.h>
#include <fcntl.h>
#include <time.h>
#include <limits.h>
#if defined(HAVE_TGMATH_H)
#include <tgmath.h>
#endif
#if defined(HAVE_MATH_H)
#include <math.h>
#endif
//#include "floating_fudge.h"
#include "spandsp/telephony.h"
#include "spandsp/fast_convert.h"
#include "spandsp/time_scale.h"
#include "spandsp/saturated.h"
#include "spandsp/private/time_scale.h"
/*
Time scaling for speech, based on the Pointer Interval Controlled
OverLap and Add (PICOLA) method, developed by Morita Naotaka.
*/
static __inline__ int amdf_pitch(int min_pitch, int max_pitch, int16_t amp[], int len)
{
int i;
int j;
int acc;
int min_acc;
int pitch;
pitch = min_pitch;
min_acc = INT_MAX;
for (i = max_pitch; i <= min_pitch; i++)
{
acc = 0;
for (j = 0; j < len; j++)
acc += abs(amp[i + j] - amp[j]);
if (acc < min_acc)
{
min_acc = acc;
pitch = i;
}
}
return pitch;
}
/*- End of function --------------------------------------------------------*/
static __inline__ void overlap_add(int16_t amp1[], int16_t amp2[], int len)
{
int i;
float weight;
float step;
step = 1.0f/len;
weight = 0.0f;
for (i = 0; i < len; i++)
{
/* TODO: saturate */
amp2[i] = (int16_t) ((float) amp1[i]*(1.0f - weight) + (float) amp2[i]*weight);
weight += step;
}
}
/*- End of function --------------------------------------------------------*/
SPAN_DECLARE(int) time_scale_rate(time_scale_state_t *s, float playout_rate)
{
if (playout_rate <= 0.0f)
return -1;
/*endif*/
if (playout_rate >= 0.99f && playout_rate <= 1.01f)
{
/* Treat rate close to normal speed as exactly normal speed, and
avoid divide by zero, and other numerical problems. */
playout_rate = 1.0f;
s->lcp=0;
}
else if (playout_rate < 1.0f)
{
s->rcomp = playout_rate/(1.0f - playout_rate);
}
else
{
s->rcomp = 1.0f/(playout_rate - 1.0f);
}
/*endif*/
s->playout_rate = playout_rate;
return 0;
}
/*- End of function --------------------------------------------------------*/
SPAN_DECLARE(time_scale_state_t *) time_scale_init(time_scale_state_t *s, int sample_rate, float playout_rate)
{
int alloced;
if (sample_rate > TIME_SCALE_MAX_SAMPLE_RATE)
return NULL;
alloced = FALSE;
if (s == NULL)
{
if ((s = (time_scale_state_t *) malloc(sizeof (*s))) == NULL)
return NULL;
/*endif*/
alloced = TRUE;
}
/*endif*/
s->sample_rate = sample_rate;
s->min_pitch = sample_rate/TIME_SCALE_MIN_PITCH;
s->max_pitch = sample_rate/TIME_SCALE_MAX_PITCH;
s->buf_len = 2*sample_rate/TIME_SCALE_MIN_PITCH;
if (time_scale_rate(s, playout_rate))
{
if (alloced)
free(s);
return NULL;
}
/*endif*/
s->rate_nudge = 0.0f;
s->fill = 0;
s->lcp = 0;
return s;
}
/*- End of function --------------------------------------------------------*/
SPAN_DECLARE(int) time_scale_release(time_scale_state_t *s)
{
return 0;
}
/*- End of function --------------------------------------------------------*/
SPAN_DECLARE(int) time_scale_free(time_scale_state_t *s)
{
free(s);
return 0;
}
/*- End of function --------------------------------------------------------*/
SPAN_DECLARE(int) time_scale(time_scale_state_t *s, int16_t out[], int16_t in[], int len)
{
double lcpf;
int pitch;
int out_len;
int in_len;
int k;
out_len = 0;
in_len = 0;
// loge( "ts: %f %d", s->playout_rate, s->lcp );
//just copy on straight playout
if( s->playout_rate == 1.0f ) {
memcpy( out, s->buf, s->fill * sizeof(int16_t) );
memcpy( out+s->fill, in, len * sizeof(int16_t) );
out_len = len + s->fill;
s->fill = 0;
// loge( "tsr1: %d", out_len );
return out_len;
}
/* Top up the buffer */
if (s->fill + len < s->buf_len)
{
/* Cannot continue without more samples */
memcpy(s->buf + s->fill, in, sizeof(int16_t)*len);
s->fill += len;
return out_len;
}
k = s->buf_len - s->fill;
memcpy(s->buf + s->fill, in, sizeof(int16_t)*k);
in_len += k;
s->fill = s->buf_len;
while (s->fill == s->buf_len)
{
while (s->lcp >= s->buf_len)
{
memcpy(out + out_len, s->buf, sizeof(int16_t)*s->buf_len);
out_len += s->buf_len;
if (len - in_len < s->buf_len)
{
/* Cannot continue without more samples */
memcpy(s->buf, in + in_len, sizeof(int16_t)*(len - in_len));
s->fill = len - in_len;
s->lcp -= s->buf_len;
return out_len;
}
memcpy(s->buf, in + in_len, sizeof(int16_t)*s->buf_len);
in_len += s->buf_len;
s->lcp -= s->buf_len;
}
if (s->lcp > 0)
{
memcpy(out + out_len, s->buf, sizeof(int16_t)*s->lcp);
out_len += s->lcp;
memcpy(s->buf, s->buf + s->lcp, sizeof(int16_t)*(s->buf_len - s->lcp));
if (len - in_len < s->lcp)
{
/* Cannot continue without more samples */
memcpy(s->buf + (s->buf_len - s->lcp), in + in_len, sizeof(int16_t)*(len - in_len));
s->fill = s->buf_len - s->lcp + len - in_len;
s->lcp = 0;
return out_len;
}
memcpy(s->buf + (s->buf_len - s->lcp), in + in_len, sizeof(int16_t)*s->lcp);
in_len += s->lcp;
s->lcp = 0;
}
if (s->playout_rate == 1.0f)
{
s->lcp = 0;//0x7FFFFFFF;
}
else
{
pitch = amdf_pitch(s->min_pitch, s->max_pitch, s->buf, s->min_pitch);
lcpf = (double) pitch*s->rcomp;
/* Nudge around to compensate for fractional samples */
s->lcp = (int) lcpf;
/* Note that s->lcp and lcpf are not the same, as lcpf has a fractional part, and s->lcp doesn't */
s->rate_nudge += s->lcp - lcpf;
if (s->rate_nudge >= 0.5f)
{
s->lcp--;
s->rate_nudge -= 1.0f;
}
else if (s->rate_nudge <= -0.5f)
{
s->lcp++;
s->rate_nudge += 1.0f;
}
if (s->playout_rate < 1.0f)
{
/* Speed up - drop a chunk of data */
overlap_add(s->buf, s->buf + pitch, pitch);
memcpy(&s->buf[pitch], &s->buf[2*pitch], sizeof(int16_t)*(s->buf_len - 2*pitch));
if (len - in_len < pitch)
{
/* Cannot continue without more samples */
memcpy(s->buf + s->buf_len - pitch, in + in_len, sizeof(int16_t)*(len - in_len));
s->fill += (len - in_len - pitch);
return out_len;
}
memcpy(s->buf + s->buf_len - pitch, in + in_len, sizeof(int16_t)*pitch);
in_len += pitch;
}
else
{
/* Slow down - insert a chunk of data */
memcpy(out + out_len, s->buf, sizeof(int16_t)*pitch);
out_len += pitch;
overlap_add(s->buf + pitch, s->buf, pitch);
}
}
}
return out_len;
}
/*- End of function --------------------------------------------------------*/
SPAN_DECLARE(int) time_scale_max_output_len(time_scale_state_t *s, int input_len)
{
return (int) (input_len*s->playout_rate + s->min_pitch + 1);
}
/*- End of function --------------------------------------------------------*/
/*- End of file ------------------------------------------------------------*/