/* This code is placed in the public domain. */ #include <stdlib.h>#include <math.h>#include "soundpipe.h" int sp_bitcrush_create(sp_bitcrush **p){    *p = malloc(sizeof(sp_bitcrush));    return SP_OK;} int sp_bitcrush_destroy(sp_bitcrush **p){    free(*p);    return SP_OK;} int sp_bitcrush_init(sp_data *sp, sp_bitcrush *p){    USED(sp);     p->bitdepth = 8;    p->srate = 10000;     p->incr = 1000;    p->sample_index = 0;    p->index = 0.0;    p->value = 0.0;    return SP_OK;} int sp_bitcrush_compute(sp_data *sp, sp_bitcrush *p, SPFLOAT *in, SPFLOAT *out){    SPFLOAT bits = pow(2, floor(p->bitdepth));    SPFLOAT foldamt = sp->sr / p->srate;    SPFLOAT sig;    *out = *in * 65536.0;    *out += 32768;    *out *= (bits / 65536.0);    *out = floor(*out);    *out = *out * (65536.0 / bits) - 32768;    sig = *out;    p->incr = foldamt;     /* apply downsampling */    if (p->index < (SPFLOAT)p->sample_index) {        p->index += p->incr;        p->value = sig;    }     *out = p->value;     p->sample_index++;     *out /= 65536.0;    return SP_OK;}