--- /dev/null
+/*
+** 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/erikd/libsamplerate/blob/master/COPYING
+*/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+
+#include "config.h"
+
+#include <float_cast.h>
+
+#if (HAVE_SNDFILE)
+
+#include <samplerate.h>
+#include <sndfile.h>
+
+#include "audio_out.h"
+
+#define ARRAY_LEN(x) ((int) (sizeof (x) / sizeof ((x) [0])))
+
+#define BUFFER_LEN 4096
+#define VARISPEED_BLOCK_LEN 64
+
+#define MIN(a,b) ((a) < (b) ? (a) : (b))
+
+#define SRC_MAGIC ((int) ('S' << 16) + ('R' << 8) + ('C'))
+#define SNDFILE_MAGIC ((int) ('s' << 24) + ('n' << 20) + ('d' << 16) + ('f' << 12) + ('i' << 8) + ('l' << 4) + 'e')
+
+#ifndef M_PI
+#define M_PI 3.14159265358979323846264338
+#endif
+
+
+typedef struct
+{ int magic ;
+ SNDFILE *sndfile ;
+ SF_INFO sfinfo ;
+
+ float buffer [BUFFER_LEN] ;
+} SNDFILE_CB_DATA ;
+
+typedef struct
+{ int magic ;
+
+ SNDFILE_CB_DATA sf ;
+
+ int freq_point ;
+
+ SRC_STATE *src_state ;
+
+} SRC_CB_DATA ;
+
+static int varispeed_get_data (SRC_CB_DATA *data, float *samples, int frames) ;
+static void varispeed_play (const char *filename, int converter) ;
+
+static long src_input_callback (void *cb_data, float **data) ;
+
+int
+main (int argc, char *argv [])
+{ const char *cptr, *progname, *filename ;
+ int k, converter ;
+
+ converter = SRC_SINC_FASTEST ;
+
+ progname = argv [0] ;
+
+ if ((cptr = strrchr (progname, '/')) != NULL)
+ progname = cptr + 1 ;
+
+ if ((cptr = strrchr (progname, '\\')) != NULL)
+ progname = cptr + 1 ;
+
+ printf ("\n"
+ " %s\n"
+ "\n"
+ " This is a demo program which plays the given file at a slowly \n"
+ " varying speed. Lots of fun with drum loops and full mixes.\n"
+ "\n"
+ " It uses Secret Rabbit Code (aka libsamplerate) to perform the \n"
+ " vari-speeding and libsndfile for file I/O.\n"
+ "\n", progname) ;
+
+ if (argc == 2)
+ filename = argv [1] ;
+ else if (argc == 4 && strcmp (argv [1], "-c") == 0)
+ { filename = argv [3] ;
+ converter = atoi (argv [2]) ;
+ }
+ else
+ { printf (" Usage :\n\n %s [-c <number>] <input file>\n\n", 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\n", k, cptr) ;
+
+ puts ("") ;
+ exit (1) ;
+ } ;
+
+ varispeed_play (filename, converter) ;
+
+ return 0 ;
+} /* main */
+
+/*==============================================================================
+*/
+
+static void
+varispeed_play (const char *filename, int converter)
+{ SRC_CB_DATA data ;
+ AUDIO_OUT *audio_out ;
+ int error ;
+
+ memset (&data, 0, sizeof (data)) ;
+
+ data.magic = SRC_MAGIC ;
+ data.sf.magic = SNDFILE_MAGIC ;
+
+ if ((data.sf.sndfile = sf_open (filename, SFM_READ, &data.sf.sfinfo)) == NULL)
+ { puts (sf_strerror (NULL)) ;
+ exit (1) ;
+ } ;
+
+ /* Initialize the sample rate converter. */
+ if ((data.src_state = src_callback_new (src_input_callback, converter, data.sf.sfinfo.channels, &error, &data.sf)) == NULL)
+ { printf ("\n\nError : src_new() failed : %s.\n\n", src_strerror (error)) ;
+ exit (1) ;
+ } ;
+
+ printf (
+
+ " Playing : %s\n"
+ " Converter : %s\n"
+ "\n"
+ " Press <control-c> to exit.\n"
+ "\n",
+ filename, src_get_name (converter)) ;
+
+ if ((audio_out = audio_open (data.sf.sfinfo.channels, data.sf.sfinfo.samplerate)) == NULL)
+ { printf ("\n\nError : audio_open () failed.\n") ;
+ exit (1) ;
+ } ;
+
+ /* Pass the data and the callbacl function to audio_play */
+ audio_play ((get_audio_callback_t) varispeed_get_data, audio_out, &data) ;
+
+ /* Cleanup */
+ audio_close (audio_out) ;
+ sf_close (data.sf.sndfile) ;
+ src_delete (data.src_state) ;
+
+} /* varispeed_play */
+
+static long
+src_input_callback (void *cb_data, float **audio)
+{ SNDFILE_CB_DATA * data = (SNDFILE_CB_DATA *) cb_data ;
+ const int input_frames = ARRAY_LEN (data->buffer) / data->sfinfo.channels ;
+ int read_frames ;
+
+ if (data->magic != SNDFILE_MAGIC)
+ { printf ("\n\n%s:%d Eeeek, something really bad happened!\n", __FILE__, __LINE__) ;
+ exit (1) ;
+ } ;
+
+ for (read_frames = 0 ; read_frames < input_frames ; )
+ { sf_count_t position ;
+
+ read_frames += sf_readf_float (data->sndfile, data->buffer + read_frames * data->sfinfo.channels, input_frames - read_frames) ;
+
+ position = sf_seek (data->sndfile, 0, SEEK_CUR) ;
+
+ if (position < 0 || position == data->sfinfo.frames)
+ sf_seek (data->sndfile, 0, SEEK_SET) ;
+ } ;
+
+ *audio = & (data->buffer [0]) ;
+
+ return input_frames ;
+} /* src_input_callback */
+
+
+/*==============================================================================
+*/
+
+static int
+varispeed_get_data (SRC_CB_DATA *data, float *samples, int out_frames)
+{ float *output ;
+ int rc, out_frame_count ;
+
+ if (data->magic != SRC_MAGIC)
+ { printf ("\n\n%s:%d Eeeek, something really bad happened!\n", __FILE__, __LINE__) ;
+ exit (1) ;
+ } ;
+
+ for (out_frame_count = 0 ; out_frame_count < out_frames ; out_frame_count += VARISPEED_BLOCK_LEN)
+ { double src_ratio = 1.0 - 0.5 * sin (data->freq_point * 2 * M_PI / 20000) ;
+
+ data->freq_point ++ ;
+
+ output = samples + out_frame_count * data->sf.sfinfo.channels ;
+
+ if ((rc = src_callback_read (data->src_state, src_ratio, VARISPEED_BLOCK_LEN, output)) < VARISPEED_BLOCK_LEN)
+ { printf ("\nError : src_callback_read short output (%d instead of %d)\n\n", rc, VARISPEED_BLOCK_LEN) ;
+ exit (1) ;
+ } ;
+ } ;
+
+ return out_frames ;
+} /* varispeed_get_data */
+
+/*==============================================================================
+*/
+
+#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.zip.com.au/~erikd/libsndfile/).\n"
+ " It is therefore completely broken and non-functional.\n"
+ "****************************************************************\n"
+ "\n"
+ ) ;
+
+ return 0 ;
+} /* main */
+
+#endif
+
projects / audio-libsamplerate.git / blobdiff