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/*
** Copyright (c) 2002-2016, Erik de Castro Lopo <erikd@mega-nerd.com>
** All rights reserved.
**
** This code is released under 2-clause BSD license. Please see the
** file at : https://github.com/libsndfile/libsamplerate/blob/master/COPYING
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#include <samplerate.h>
#include "util.h"
#define BUFFER_LEN (1<<15)
#define BLOCK_LEN 100
static void stream_test (int converter, double ratio) ;
int
main (void)
{ static double src_ratios [] =
{ 0.3, 0.9, 1.1, 3.0
} ;
int k ;
puts ("\n Zero Order Hold interpolator:") ;
for (k = 0 ; k < ARRAY_LEN (src_ratios) ; k++)
stream_test (SRC_ZERO_ORDER_HOLD, src_ratios [k]) ;
puts ("\n Linear interpolator:") ;
for (k = 0 ; k < ARRAY_LEN (src_ratios) ; k++)
stream_test (SRC_LINEAR, src_ratios [k]) ;
puts ("\n Sinc interpolator:") ;
for (k = 0 ; k < ARRAY_LEN (src_ratios) ; k++)
stream_test (SRC_SINC_FASTEST, src_ratios [k]) ;
puts ("") ;
return 0 ;
} /* main */
static void
stream_test (int converter, double src_ratio)
{ static float input [BUFFER_LEN], output [BUFFER_LEN] ;
SRC_STATE *src_state ;
SRC_DATA src_data ;
int input_len, output_len, current_in, current_out ;
int error, terminate ;
printf ("\tstreaming_test (SRC ratio = %6.4f) ........... ", src_ratio) ;
fflush (stdout) ;
/* Calculate maximun input and output lengths. */
if (src_ratio >= 1.0)
{ output_len = BUFFER_LEN ;
input_len = (int) floor (BUFFER_LEN / src_ratio) ;
}
else
{ input_len = BUFFER_LEN ;
output_len = (int) floor (BUFFER_LEN * src_ratio) ;
} ;
/* Reduce input_len by 10 so output is longer than necessary. */
input_len -= 10 ;
if (output_len > BUFFER_LEN)
{ printf ("\n\nLine %d : output_len > BUFFER_LEN\n\n", __LINE__) ;
exit (1) ;
} ;
current_in = current_out = 0 ;
/* Perform sample rate conversion. */
if ((src_state = src_new (converter, 1, &error)) == NULL)
{ printf ("\n\nLine %d : src_new() failed : %s\n\n", __LINE__, src_strerror (error)) ;
exit (1) ;
} ;
src_data.end_of_input = 0 ; /* Set this later. */
src_data.data_in = input ;
src_data.input_frames = BLOCK_LEN ;
src_data.src_ratio = src_ratio ;
src_data.data_out = output ;
src_data.output_frames = BLOCK_LEN ;
while (1)
{ if ((error = src_process (src_state, &src_data)))
{ printf ("\n\nLine %d : %s\n\n", __LINE__, src_strerror (error)) ;
printf ("src_data.input_frames : %ld\n", src_data.input_frames) ;
printf ("src_data.output_frames : %ld\n", src_data.output_frames) ;
exit (1) ;
} ;
if (src_data.end_of_input && src_data.output_frames_gen == 0)
break ;
current_in += src_data.input_frames_used ;
current_out += src_data.output_frames_gen ;
src_data.data_in += src_data.input_frames_used ;
src_data.data_out += src_data.output_frames_gen ;
src_data.input_frames = MIN (BLOCK_LEN, input_len - current_in) ;
src_data.output_frames = MIN (BLOCK_LEN, output_len - current_out) ;
src_data.end_of_input = (current_in >= input_len) ? 1 : 0 ;
} ;
src_state = src_delete (src_state) ;
terminate = (int) ceil ((src_ratio >= 1.0) ? src_ratio : 1.0 / src_ratio) ;
if (fabs (current_out - src_ratio * input_len) > 2 * terminate)
{ printf ("\n\nLine %d : bad output data length %d should be %d.\n", __LINE__,
current_out, (int) floor (src_ratio * input_len)) ;
printf ("\tsrc_ratio : %.4f\n", src_ratio) ;
printf ("\tinput_len : %d\n\toutput_len : %d\n\n", input_len, output_len) ;
exit (1) ;
} ;
if (current_in != input_len)
{ printf ("\n\nLine %d : unused input.\n", __LINE__) ;
printf ("\tinput_len : %d\n", input_len) ;
printf ("\tinput_frames_used : %d\n\n", current_in) ;
exit (1) ;
} ;
puts ("ok") ;
return ;
} /* stream_test */
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