ref: d86441db3eb3b57d19124edda6018d330f2458ba
dir: /examples/sndfile-resample.c/
/* ** Copyright (C) 2002-2008 Erik de Castro Lopo <erikd@mega-nerd.com> ** ** This program is free software; you can redistribute it and/or modify ** it under the terms of the GNU General Public License as published by ** the Free Software Foundation; either version 2 of the License, or ** (at your option) any later version. ** ** 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 General Public License for more details. ** ** You should have received a copy of the GNU General Public License ** along with this program; if not, write to the Free Software ** Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA. */ #include "config.h" #include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <string.h> #include <math.h> #if (HAVE_SNDFILE) #include <samplerate.h> #include <sndfile.h> #define DEFAULT_CONVERTER SRC_SINC_MEDIUM_QUALITY #define BUFFER_LEN 4096 /*-(1<<16)-*/ static void usage_exit (const char *progname) ; static sf_count_t sample_rate_convert (SNDFILE *infile, SNDFILE *outfile, int converter, double src_ratio, int channels, double * gain) ; static double apply_gain (float * data, long frames, int channels, double max, double gain) ; int main (int argc, char *argv []) { SNDFILE *infile, *outfile ; SF_INFO sfinfo ; sf_count_t count ; double src_ratio = -1.0, gain = 1.0 ; int new_sample_rate = -1, k, converter, max_speed = SF_FALSE ; if (argc == 2 && strcmp (argv [1], "--version") == 0) { char buffer [64], *cptr ; if ((cptr = strrchr (argv [0], '/')) != NULL) argv [0] = cptr + 1 ; if ((cptr = strrchr (argv [0], '\\')) != NULL) argv [0] = cptr + 1 ; sf_command (NULL, SFC_GET_LIB_VERSION, buffer, sizeof (buffer)) ; printf ("%s (%s,%s)\n", argv [0], src_get_version (), buffer) ; exit (0) ; } ; if (argc != 5 && argc != 7 && argc != 8) usage_exit (argv [0]) ; /* Set default converter. */ converter = DEFAULT_CONVERTER ; for (k = 1 ; k < argc - 2 ; k++) { if (strcmp (argv [k], "--max-speed") == 0) max_speed = SF_TRUE ; else if (strcmp (argv [k], "-to") == 0) { k ++ ; new_sample_rate = atoi (argv [k]) ; } else if (strcmp (argv [k], "-by") == 0) { k ++ ; src_ratio = atof (argv [k]) ; } else if (strcmp (argv [k], "-c") == 0) { k ++ ; converter = atoi (argv [k]) ; } else usage_exit (argv [0]) ; } ; if (new_sample_rate <= 0 && src_ratio <= 0.0) usage_exit (argv [0]) ; if (src_get_name (converter) == NULL) { printf ("Error : bad converter number.\n") ; usage_exit (argv [0]) ; } ; if (strcmp (argv [argc - 2], argv [argc - 1]) == 0) { printf ("Error : input and output file names are the same.\n") ; exit (1) ; } ; if ((infile = sf_open (argv [argc - 2], SFM_READ, &sfinfo)) == NULL) { printf ("Error : Not able to open input file '%s'\n", argv [argc - 2]) ; exit (1) ; } ; printf ("Input File : %s\n", argv [argc - 2]) ; printf ("Sample Rate : %d\n", sfinfo.samplerate) ; printf ("Input Frames : %ld\n\n", (long) sfinfo.frames) ; if (new_sample_rate > 0) { src_ratio = (1.0 * new_sample_rate) / sfinfo.samplerate ; sfinfo.samplerate = new_sample_rate ; } else if (src_is_valid_ratio (src_ratio)) sfinfo.samplerate = (int) floor (sfinfo.samplerate * src_ratio) ; else { printf ("Not able to determine new sample rate. Exiting.\n") ; sf_close (infile) ; exit (1) ; } ; if (fabs (src_ratio - 1.0) < 1e-20) { printf ("Target samplerate and input samplerate are the same. Exiting.\n") ; sf_close (infile) ; exit (0) ; } ; printf ("SRC Ratio : %f\n", src_ratio) ; printf ("Converter : %s\n\n", src_get_name (converter)) ; if (src_is_valid_ratio (src_ratio) == 0) { printf ("Error : Sample rate change out of valid range.\n") ; sf_close (infile) ; exit (1) ; } ; /* Delete the output file length to zero if already exists. */ remove (argv [argc - 1]) ; if ((outfile = sf_open (argv [argc - 1], SFM_WRITE, &sfinfo)) == NULL) { printf ("Error : Not able to open output file '%s'\n", argv [argc - 1]) ; sf_close (infile) ; exit (1) ; } ; if (max_speed) { /* This is mainly for the comparison program tests/src-evaluate.c */ sf_command (outfile, SFC_SET_ADD_PEAK_CHUNK, NULL, SF_FALSE) ; } else { /* Update the file header after every write. */ sf_command (outfile, SFC_SET_UPDATE_HEADER_AUTO, NULL, SF_TRUE) ; } ; sf_command (outfile, SFC_SET_CLIPPING, NULL, SF_TRUE) ; printf ("Output file : %s\n", argv [argc - 1]) ; printf ("Sample Rate : %d\n", sfinfo.samplerate) ; do count = sample_rate_convert (infile, outfile, converter, src_ratio, sfinfo.channels, &gain) ; while (count < 0) ; printf ("Output Frames : %ld\n\n", (long) count) ; sf_close (infile) ; sf_close (outfile) ; return 0 ; } /* main */ /*============================================================================== */ static sf_count_t sample_rate_convert (SNDFILE *infile, SNDFILE *outfile, int converter, double src_ratio, int channels, double * gain) { static float input [BUFFER_LEN] ; static float output [BUFFER_LEN] ; SRC_STATE *src_state ; SRC_DATA src_data ; int error ; double max = 0.0 ; sf_count_t output_count = 0 ; sf_seek (infile, 0, SEEK_SET) ; sf_seek (outfile, 0, SEEK_SET) ; /* Initialize the sample rate converter. */ if ((src_state = src_new (converter, channels, &error)) == NULL) { printf ("\n\nError : src_new() failed : %s.\n\n", src_strerror (error)) ; exit (1) ; } ; src_data.end_of_input = 0 ; /* Set this later. */ /* Start with zero to force load in while loop. */ src_data.input_frames = 0 ; src_data.data_in = input ; src_data.src_ratio = src_ratio ; src_data.data_out = output ; src_data.output_frames = BUFFER_LEN /channels ; while (1) { /* If the input buffer is empty, refill it. */ if (src_data.input_frames == 0) { src_data.input_frames = sf_readf_float (infile, input, BUFFER_LEN / channels) ; src_data.data_in = input ; /* The last read will not be a full buffer, so snd_of_input. */ if (src_data.input_frames < BUFFER_LEN / channels) src_data.end_of_input = SF_TRUE ; } ; if ((error = src_process (src_state, &src_data))) { printf ("\nError : %s\n", src_strerror (error)) ; exit (1) ; } ; /* Terminate if done. */ if (src_data.end_of_input && src_data.output_frames_gen == 0) break ; max = apply_gain (src_data.data_out, src_data.output_frames_gen, channels, max, *gain) ; /* Write output. */ sf_writef_float (outfile, output, src_data.output_frames_gen) ; output_count += src_data.output_frames_gen ; src_data.data_in += src_data.input_frames_used * channels ; src_data.input_frames -= src_data.input_frames_used ; } ; src_state = src_delete (src_state) ; if (max > 1.0) { *gain = 1.0 / max ; printf ("\nOutput has clipped. Restarting conversion to prevent clipping.\n\n") ; output_count = 0 ; sf_command (outfile, SFC_FILE_TRUNCATE, &output_count, sizeof (output_count)) ; return -1 ; } ; return output_count ; } /* sample_rate_convert */ static double apply_gain (float * data, long frames, int channels, double max, double gain) { long k ; for (k = 0 ; k < frames * channels ; k++) { data [k] *= gain ; if (fabs (data [k]) > max) max = fabs (data [k]) ; } ; return max ; } /* apply_gain */ static void usage_exit (const char *progname) { char lsf_ver [128] ; const char *cptr ; int k ; if ((cptr = strrchr (progname, '/')) != NULL) progname = cptr + 1 ; if ((cptr = strrchr (progname, '\\')) != NULL) progname = cptr + 1 ; sf_command (NULL, SFC_GET_LIB_VERSION, lsf_ver, sizeof (lsf_ver)) ; printf ("\n" " A Sample Rate Converter using libsndfile for file I/O and Secret \n" " Rabbit Code (aka libsamplerate) for performing the conversion.\n" " It works on any file format supported by libsndfile with any \n" " number of channels (limited only by host memory).\n" "\n" " %s\n" " %s\n" "\n" " Usage : \n" " %s -to <new sample rate> [-c <number>] <input file> <output file>\n" " %s -by <amount> [-c <number>] <input file> <output file>\n" "\n", src_get_version (), lsf_ver, progname, progname) ; puts ( " The optional -c argument allows the converter type to be chosen from\n" " the following list :" "\n" ) ; for (k = 0 ; (cptr = src_get_name (k)) != NULL ; k++) printf (" %d : %s%s\n", k, cptr, k == DEFAULT_CONVERTER ? " (default)" : "") ; puts ("") ; exit (1) ; } /* usage_exit */ /*============================================================================== */ #else /* (HAVE_SNFILE == 0) */ /* Alternative main function when libsndfile is not available. */ int main (void) { puts ( "\n" "****************************************************************\n" " This example program was compiled without libsndfile \n" " (http://www.mega-nerd.com/libsndfile/).\n" " It is therefore completely broken and non-functional.\n" "****************************************************************\n" "\n" ) ; return 0 ; } /* main */ #endif