ref: dd88a3bf36323b1917aad54943766529bcfbe9d0
dir: /modules/wavin.c/
/* This code is placed in the public domain. */ #include <stdlib.h> #include <math.h> #include "soundpipe.h" #include "lib/dr_wav/sp_dr_wav.h" #define WAVIN_BUFSIZE 1024 struct sp_wavin { SPFLOAT buf[WAVIN_BUFSIZE]; int count; drwav *wav; unsigned long pos; unsigned long buf_start; unsigned long buf_end; }; int sp_wavin_create(sp_wavin **p) { *p = malloc(sizeof(sp_wavin)); return SP_OK; } int sp_wavin_destroy(sp_wavin **p) { sp_drwav_uninit((*p)->wav); free((*p)->wav); free(*p); return SP_OK; } int sp_wavin_init(sp_data *sp, sp_wavin *p, const char *filename) { p->count = 0; p->pos = 0; p->buf_start = 0; p->buf_end = 0; p->wav = calloc(1, sp_drwav_size()); sp_drwav_init_file(p->wav, filename); return SP_OK; } static void read_block(sp_data *sp, sp_wavin *p, unsigned long position) { unsigned long samps_read; sp_wavin_seek(sp, p, position); samps_read = sp_drwav_read_f32(p->wav, WAVIN_BUFSIZE, p->buf); p->buf_start = position; p->buf_end = position + samps_read - 1; } int sp_wavin_compute(sp_data *sp, sp_wavin *p, SPFLOAT *in, SPFLOAT *out) { if (p->pos > sp_drwav_sampcount(p->wav)) { *out = 0; return SP_OK; } if (p->count == 0) { read_block(sp, p, p->pos); } *out = p->buf[p->count]; p->count = (p->count + 1) % WAVIN_BUFSIZE; p->pos++; return SP_OK; } int sp_wavin_get_sample(sp_data *sp, sp_wavin *p, SPFLOAT *out, SPFLOAT pos) { unsigned long ipos; float samp1, samp2; float frac; int buf_pos; ipos = floor(pos); if(!(ipos >= p->buf_start && ipos < (p->buf_end - 1)) || (p->buf_start == p->buf_end)) { read_block(sp, p, ipos); } frac = pos - ipos; buf_pos = (int)(ipos - p->buf_start); samp1 = p->buf[buf_pos]; samp2 = p->buf[buf_pos + 1]; *out = samp1 + (samp2 - samp1) * frac; return SP_OK; } int sp_wavin_reset_to_start(sp_data *sp, sp_wavin *p) { sp_wavin_seek(sp, p, 0); return SP_OK; } int sp_wavin_seek(sp_data *sp, sp_wavin *p, unsigned long sample) { sp_drwav_seek_to_sample(p->wav, sample); return SP_OK; }