/*** 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*/ #include "src_config.h" #include <stdio.h>#include <stdlib.h>#include <string.h>#include <math.h>#include <time.h> #if (HAVE_FFTW3) #include <fftw3.h> #include <samplerate.h> #include "util.h" #define	BUFFER_LEN		50000#define	MAX_FREQS		4#define	MAX_RATIOS		6#define	MAX_SPEC_LEN	(1<<15) #ifndef	M_PI#define	M_PI			3.14159265358979323846264338#endif enum{	BOOLEAN_FALSE	= 0,	BOOLEAN_TRUE	= 1} ; typedef struct{	int		freq_count ;	double	freqs [MAX_FREQS] ; 	double	src_ratio ;	int		pass_band_peaks ; 	double	snr ;	double	peak_value ;} SINGLE_TEST ; typedef struct{	int			converter ;	int			tests ;	int			do_bandwidth_test ;	SINGLE_TEST	test_data [10] ;} CONVERTER_TEST ; static double snr_test (SINGLE_TEST *snr_test_data, int number, int converter, int verbose) ;static double find_peak (float *output, int output_len) ;static double bandwidth_test (int converter, int verbose) ; intmain (int argc, char *argv []){	CONVERTER_TEST snr_test_data [] =	{		{	SRC_ZERO_ORDER_HOLD,			8,			BOOLEAN_FALSE,			{	{	1,	{ 0.01111111111 },		3.0,		1,	 28.0,	1.0 },				{	1,	{ 0.01111111111 },		0.6,		1,	 36.0,	1.0 },				{	1,	{ 0.01111111111 },		0.3,		1,	 36.0,	1.0 },				{	1,	{ 0.01111111111 },		1.0,		1,	150.0,	1.0 },				{	1,	{ 0.01111111111 },		1.001,		1,	 38.0,	1.0 },				{	2,	{ 0.011111, 0.324 },	1.9999,		2,	 14.0,	1.0 },				{	2,	{ 0.012345, 0.457 },	0.456789,	1,	 12.0,	1.0 },				{	1,	{ 0.3511111111 },		1.33,		1,	 10.0,	1.0 }				}			}, 		{	SRC_LINEAR,			8,			BOOLEAN_FALSE,			{	{	1,	{ 0.01111111111 },		3.0,		1,	 73.0,	1.0 },				{	1,	{ 0.01111111111 },		0.6,		1,	 73.0,	1.0 },				{	1,	{ 0.01111111111 },		0.3,		1,	 73.0,	1.0 },				{	1,	{ 0.01111111111 },		1.0,		1,	150.0,	1.0 },				{	1,	{ 0.01111111111 },		1.001,		1,	 77.0,	1.0 },				{	2,	{ 0.011111, 0.324 },	1.9999,		2,	 15.0,	0.94 },				{	2,	{ 0.012345, 0.457 },	0.456789,	1,	 25.0,	0.96 },				{	1,	{ 0.3511111111 },		1.33,		1,	 22.0,	0.99 }				}			}, 		{	SRC_SINC_FASTEST,			9,			BOOLEAN_TRUE,			{	{	1,	{ 0.01111111111 },		3.0,		1,	100.0,	1.0 },				{	1,	{ 0.01111111111 },		0.6,		1,	 99.0,	1.0 },				{	1,	{ 0.01111111111 },		0.3,		1,	100.0,	1.0 },				{	1,	{ 0.01111111111 },		1.0,		1,	150.0,	1.0 },				{	1,	{ 0.01111111111 },		1.001,		1,	100.0,	1.0 },				{	2,	{ 0.011111, 0.324 },	1.9999,		2,	 97.0,	1.0 },				{	2,	{ 0.012345, 0.457 },	0.456789,	1,	100.0,	0.5 },				{	2,	{ 0.011111, 0.45 },		0.6,		1,	 97.0,	0.5 },				{	1,	{ 0.3511111111 },		1.33,		1,	 97.0,	1.0 }				}			}, 		{	SRC_SINC_MEDIUM_QUALITY,			9,			BOOLEAN_TRUE,			{	{	1,	{ 0.01111111111 },		3.0,		1,	145.0,	1.0 },				{	1,	{ 0.01111111111 },		0.6,		1,	132.0,	1.0 },				{	1,	{ 0.01111111111 },		0.3,		1,	138.0,	1.0 },				{	1,	{ 0.01111111111 },		1.0,		1,	157.0,	1.0 },				{	1,	{ 0.01111111111 },		1.001,		1,	148.0,	1.0 },				{	2,	{ 0.011111, 0.324 },	1.9999,		2,	127.0,	1.0 },				{	2,	{ 0.012345, 0.457 },	0.456789,	1,	123.0,	0.5 },				{	2,	{ 0.011111, 0.45 },		0.6,		1,	126.0,	0.5 },				{	1,	{ 0.43111111111 },		1.33,		1,	121.0,	1.0 }				}			}, 		{	SRC_SINC_BEST_QUALITY,			9,			BOOLEAN_TRUE,			{	{	1,	{ 0.01111111111 },		3.0,		1,	147.0,	1.0 },				{	1,	{ 0.01111111111 },		0.6,		1,	147.0,	1.0 },				{	1,	{ 0.01111111111 },		0.3,		1,	148.0,	1.0 },				{	1,	{ 0.01111111111 },		1.0,		1,	155.0,	1.0 },				{	1,	{ 0.01111111111 },		1.001,		1,	148.0,	1.0 },				{	2,	{ 0.011111, 0.324 },	1.9999,		2,	146.0,	1.0 },				{	2,	{ 0.012345, 0.457 },	0.456789,	1,	147.0,	0.5 },				{	2,	{ 0.011111, 0.45 },		0.6,		1,	144.0,	0.5 },				{	1,	{ 0.43111111111 },		1.33,		1,	145.0,	1.0 }				}			},		} ; /* snr_test_data */ 	double	best_snr, snr, freq3dB ;	int 	j, k, converter, verbose = 0 ; 	if (argc == 2 && strcmp (argv [1], "--verbose") == 0)		verbose = 1 ; 	puts ("") ; 	for (j = 0 ; j < ARRAY_LEN (snr_test_data) ; j++)	{	best_snr = 5000.0 ; 		converter = snr_test_data [j].converter ; 		printf ("    Converter %d : %s\n", converter, src_get_name (converter)) ;		printf ("    %s\n", src_get_description (converter)) ; 		for (k = 0 ; k < snr_test_data [j].tests ; k++)		{	snr = snr_test (&(snr_test_data [j].test_data [k]), k, converter, verbose) ;			if (best_snr > snr)				best_snr = snr ;			} ; 		printf ("    Worst case Signal-to-Noise Ratio : %.2f dB.\n", best_snr) ; 		if (snr_test_data [j].do_bandwidth_test == BOOLEAN_FALSE)		{	puts ("    Bandwith test not performed on this converter.\n") ;			continue ;			} 		freq3dB = bandwidth_test (converter, verbose) ; 		printf ("    Measured -3dB rolloff point      : %5.2f %%.\n\n", freq3dB) ;		} ; 	fftw_cleanup () ; 	return 0 ;} /* main */ /*==============================================================================*/ static doublesnr_test (SINGLE_TEST *test_data, int number, int converter, int verbose){	static float data [BUFFER_LEN + 1] ;	static float output [MAX_SPEC_LEN] ; 	SRC_STATE	*src_state ;	SRC_DATA	src_data ; 	double		output_peak, snr ;	int 		k, output_len, input_len, error ; 	if (verbose != 0)	{	printf ("\tSignal-to-Noise Ratio Test %d.\n"				"\t=====================================\n", number) ;		printf ("\tFrequencies : [ ") ;		for (k = 0 ; k < test_data->freq_count ; k++)			printf ("%6.4f ", test_data->freqs [k]) ; 		printf ("]\n\tSRC Ratio   : %8.4f\n", test_data->src_ratio) ;		}	else	{	printf ("\tSignal-to-Noise Ratio Test %d : ", number) ;		fflush (stdout) ;		} ; 	/* Set up the output array. */	if (test_data->src_ratio >= 1.0)	{	output_len = MAX_SPEC_LEN ;		input_len = (int) ceil (MAX_SPEC_LEN / test_data->src_ratio) ;		if (input_len > BUFFER_LEN)			input_len = BUFFER_LEN ;		}	else	{	input_len = BUFFER_LEN ;		output_len = (int) ceil (BUFFER_LEN * test_data->src_ratio) ;		output_len &= ((~0u) << 4) ;		if (output_len > MAX_SPEC_LEN)			output_len = MAX_SPEC_LEN ;		input_len = (int) ceil (output_len / test_data->src_ratio) ;		} ; 	memset (output, 0, sizeof (output)) ; 	/* Generate input data array. */	gen_windowed_sines (test_data->freq_count, test_data->freqs, 1.0, data, input_len) ; 	/* 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 = 1 ; /* Only one buffer worth of input. */ 	src_data.data_in = data ;	src_data.input_frames = input_len ; 	src_data.src_ratio = test_data->src_ratio ; 	src_data.data_out = output ;	src_data.output_frames = output_len ; 	if ((error = src_process (src_state, &src_data)))	{	printf ("\n\nLine %d : %s\n\n", __LINE__, src_strerror (error)) ;		exit (1) ;		} ; 	src_state = src_delete (src_state) ; 	if (verbose != 0)		printf ("\tOutput Len  :   %ld\n", src_data.output_frames_gen) ; 	if (abs ((int) (src_data.output_frames_gen - output_len)) > 4)	{	printf ("\n\nLine %d : output data length should be %d.\n\n", __LINE__, output_len) ;		exit (1) ;		} ; 	/* Check output peak. */	output_peak = find_peak (output, src_data.output_frames_gen) ; 	if (verbose != 0)		printf ("\tOutput Peak :   %6.4f\n", output_peak) ; 	if (fabs (output_peak - test_data->peak_value) > 0.01)	{	printf ("\n\nLine %d : output peak (%6.4f) should be %6.4f\n\n", __LINE__, output_peak, test_data->peak_value) ;		save_oct_float ("snr_test.dat", data, BUFFER_LEN, output, output_len) ;		exit (1) ;		} ; 	/* Calculate signal-to-noise ratio. */	snr = calculate_snr (output, src_data.output_frames_gen, test_data->pass_band_peaks) ; 	if (snr < 0.0)	{	/* An error occurred. */		save_oct_float ("snr_test.dat", data, BUFFER_LEN, output, src_data.output_frames_gen) ;		exit (1) ;		} ; 	if (verbose != 0)		printf ("\tSNR Ratio   :   %.2f dB\n", snr) ; 	if (snr < test_data->snr)	{	printf ("\n\nLine %d : SNR (%5.2f) should be > %6.2f dB\n\n", __LINE__, snr, test_data->snr) ;		exit (1) ;		} ; 	if (verbose != 0)		puts ("\t-------------------------------------\n\tPass\n") ;	else		puts ("Pass") ; 	return snr ;} /* snr_test */ static doublefind_peak (float *data, int len){	double 	peak = 0.0 ;	int		k = 0 ; 	for (k = 0 ; k < len ; k++)		if (fabs (data [k]) > peak)			peak = fabs (data [k]) ; 	return peak ;} /* find_peak */  static doublefind_attenuation (double freq, int converter, int verbose){	static float input	[BUFFER_LEN] ;	static float output [2 * BUFFER_LEN] ; 	SRC_DATA	src_data ;	double 		output_peak ;	int			error ; 	gen_windowed_sines (1, &freq, 1.0, input, BUFFER_LEN) ; 	src_data.end_of_input = 1 ; /* Only one buffer worth of input. */ 	src_data.data_in = input ;	src_data.input_frames = BUFFER_LEN ; 	src_data.src_ratio = 1.999 ; 	src_data.data_out = output ;	src_data.output_frames = ARRAY_LEN (output) ; 	if ((error = src_simple (&src_data, converter, 1)))	{	printf ("\n\nLine %d : %s\n\n", __LINE__, src_strerror (error)) ;		exit (1) ;		} ; 	output_peak = find_peak (output, ARRAY_LEN (output)) ; 	if (verbose)		printf ("\tFreq : %6f   InPeak : %6f    OutPeak : %6f   Atten : %6.2f dB\n",				freq, 1.0, output_peak, 20.0 * log10 (1.0 / output_peak)) ; 	return 20.0 * log10 (1.0 / output_peak) ;} /* find_attenuation */ static doublebandwidth_test (int converter, int verbose){	double	f1, f2, a1, a2 ;	double	freq, atten ; 	f1 = 0.35 ;	a1 = find_attenuation (f1, converter, verbose) ; 	f2 = 0.495 ;	a2 = find_attenuation (f2, converter, verbose) ; 	if (a1 > 3.0 || a2 < 3.0)	{	printf ("\n\nLine %d : cannot bracket 3dB point.\n\n", __LINE__) ;		exit (1) ;		} ; 	while (a2 - a1 > 1.0)	{	freq = f1 + 0.5 * (f2 - f1) ;		atten = find_attenuation (freq, converter, verbose) ; 		if (atten < 3.0)		{	f1 = freq ;			a1 = atten ;			}		else		{	f2 = freq ;			a2 = atten ;			} ;		} ; 	freq = f1 + (3.0 - a1) * (f2 - f1) / (a2 - a1) ; 	return 200.0 * freq ;} /* bandwidth_test */ #else /* (HAVE_FFTW3) == 0 */ /* Alternative main function when librfftw is not available. */ intmain (void){	puts ("\n"		"****************************************************************\n"		" This test cannot be run without FFTW (http://www.fftw.org/).\n"		" Both the real and the complex versions of the library are\n"		" required.") ;	puts ("****************************************************************\n") ; 	return 0 ;} /* main */ #endif