diff options
Diffstat (limited to 'tran/biquadfilt.c')
| -rw-r--r-- | tran/biquadfilt.c | 343 |
1 files changed, 343 insertions, 0 deletions
diff --git a/tran/biquadfilt.c b/tran/biquadfilt.c new file mode 100644 index 0000000..c5e81da --- /dev/null +++ b/tran/biquadfilt.c @@ -0,0 +1,343 @@ +#include "stdio.h" +#ifndef mips +#include "stdlib.h" +#endif +#include "xlisp.h" +#include "sound.h" + +#include "falloc.h" +#include "cext.h" +#include "biquadfilt.h" + +void biquadfilt_free(); + + +typedef struct biquadfilt_susp_struct { + snd_susp_node susp; + long terminate_cnt; + boolean logically_stopped; + sound_type s; + long s_cnt; + sample_block_values_type s_ptr; + + double z1; + double z2; + double b0; + double b1; + double b2; + double a1; + double a2; +} biquadfilt_susp_node, *biquadfilt_susp_type; + + +void biquadfilt_n_fetch(register biquadfilt_susp_type susp, snd_list_type snd_list) +{ + int cnt = 0; /* how many samples computed */ + int togo; + int n; + sample_block_type out; + register sample_block_values_type out_ptr; + + register sample_block_values_type out_ptr_reg; + + register double z1_reg; + register double z2_reg; + register double b0_reg; + register double b1_reg; + register double b2_reg; + register double a1_reg; + register double a2_reg; + register sample_block_values_type s_ptr_reg; + falloc_sample_block(out, "biquadfilt_n_fetch"); + out_ptr = out->samples; + snd_list->block = out; + + while (cnt < max_sample_block_len) { /* outer loop */ + /* first compute how many samples to generate in inner loop: */ + /* don't overflow the output sample block: */ + togo = max_sample_block_len - cnt; + + /* don't run past the s input sample block: */ + susp_check_term_log_samples(s, s_ptr, s_cnt); + togo = min(togo, susp->s_cnt); + + /* don't run past terminate time */ + if (susp->terminate_cnt != UNKNOWN && + susp->terminate_cnt <= susp->susp.current + cnt + togo) { + togo = susp->terminate_cnt - (susp->susp.current + cnt); + if (togo == 0) break; + } + + + /* don't run past logical stop time */ + if (!susp->logically_stopped && susp->susp.log_stop_cnt != UNKNOWN) { + int to_stop = susp->susp.log_stop_cnt - (susp->susp.current + cnt); + /* break if to_stop == 0 (we're at the logical stop) + * AND cnt > 0 (we're not at the beginning of the + * output block). + */ + if (to_stop < togo) { + if (to_stop == 0) { + if (cnt) { + togo = 0; + break; + } else /* keep togo as is: since cnt == 0, we + * can set the logical stop flag on this + * output block + */ + susp->logically_stopped = true; + } else /* limit togo so we can start a new + * block at the LST + */ + togo = to_stop; + } + } + + n = togo; + z1_reg = susp->z1; + z2_reg = susp->z2; + b0_reg = susp->b0; + b1_reg = susp->b1; + b2_reg = susp->b2; + a1_reg = susp->a1; + a2_reg = susp->a2; + s_ptr_reg = susp->s_ptr; + out_ptr_reg = out_ptr; + if (n) do { /* the inner sample computation loop */ +double z0; z0 = *s_ptr_reg++ + a1_reg*z1_reg + a2_reg*z2_reg; + *out_ptr_reg++ = (sample_type) (z0*b0_reg + z1_reg*b1_reg + z2_reg*b2_reg); + z2_reg = z1_reg; z1_reg = z0;; + } while (--n); /* inner loop */ + + susp->z1 = z1_reg; + susp->z2 = z2_reg; + /* using s_ptr_reg is a bad idea on RS/6000: */ + susp->s_ptr += togo; + out_ptr += togo; + susp_took(s_cnt, togo); + cnt += togo; + } /* outer loop */ + + /* test for termination */ + if (togo == 0 && cnt == 0) { + snd_list_terminate(snd_list); + } else { + snd_list->block_len = cnt; + susp->susp.current += cnt; + } + /* test for logical stop */ + if (susp->logically_stopped) { + snd_list->logically_stopped = true; + } else if (susp->susp.log_stop_cnt == susp->susp.current) { + susp->logically_stopped = true; + } +} /* biquadfilt_n_fetch */ + + +void biquadfilt_s_fetch(register biquadfilt_susp_type susp, snd_list_type snd_list) +{ + int cnt = 0; /* how many samples computed */ + int togo; + int n; + sample_block_type out; + register sample_block_values_type out_ptr; + + register sample_block_values_type out_ptr_reg; + + register double z1_reg; + register double z2_reg; + register double b0_reg; + register double b1_reg; + register double b2_reg; + register double a1_reg; + register double a2_reg; + register sample_type s_scale_reg = susp->s->scale; + register sample_block_values_type s_ptr_reg; + falloc_sample_block(out, "biquadfilt_s_fetch"); + out_ptr = out->samples; + snd_list->block = out; + + while (cnt < max_sample_block_len) { /* outer loop */ + /* first compute how many samples to generate in inner loop: */ + /* don't overflow the output sample block: */ + togo = max_sample_block_len - cnt; + + /* don't run past the s input sample block: */ + susp_check_term_log_samples(s, s_ptr, s_cnt); + togo = min(togo, susp->s_cnt); + + /* don't run past terminate time */ + if (susp->terminate_cnt != UNKNOWN && + susp->terminate_cnt <= susp->susp.current + cnt + togo) { + togo = susp->terminate_cnt - (susp->susp.current + cnt); + if (togo == 0) break; + } + + + /* don't run past logical stop time */ + if (!susp->logically_stopped && susp->susp.log_stop_cnt != UNKNOWN) { + int to_stop = susp->susp.log_stop_cnt - (susp->susp.current + cnt); + /* break if to_stop == 0 (we're at the logical stop) + * AND cnt > 0 (we're not at the beginning of the + * output block). + */ + if (to_stop < togo) { + if (to_stop == 0) { + if (cnt) { + togo = 0; + break; + } else /* keep togo as is: since cnt == 0, we + * can set the logical stop flag on this + * output block + */ + susp->logically_stopped = true; + } else /* limit togo so we can start a new + * block at the LST + */ + togo = to_stop; + } + } + + n = togo; + z1_reg = susp->z1; + z2_reg = susp->z2; + b0_reg = susp->b0; + b1_reg = susp->b1; + b2_reg = susp->b2; + a1_reg = susp->a1; + a2_reg = susp->a2; + s_ptr_reg = susp->s_ptr; + out_ptr_reg = out_ptr; + if (n) do { /* the inner sample computation loop */ +double z0; z0 = (s_scale_reg * *s_ptr_reg++) + a1_reg*z1_reg + a2_reg*z2_reg; + *out_ptr_reg++ = (sample_type) (z0*b0_reg + z1_reg*b1_reg + z2_reg*b2_reg); + z2_reg = z1_reg; z1_reg = z0;; + } while (--n); /* inner loop */ + + susp->z1 = z1_reg; + susp->z2 = z2_reg; + /* using s_ptr_reg is a bad idea on RS/6000: */ + susp->s_ptr += togo; + out_ptr += togo; + susp_took(s_cnt, togo); + cnt += togo; + } /* outer loop */ + + /* test for termination */ + if (togo == 0 && cnt == 0) { + snd_list_terminate(snd_list); + } else { + snd_list->block_len = cnt; + susp->susp.current += cnt; + } + /* test for logical stop */ + if (susp->logically_stopped) { + snd_list->logically_stopped = true; + } else if (susp->susp.log_stop_cnt == susp->susp.current) { + susp->logically_stopped = true; + } +} /* biquadfilt_s_fetch */ + + +void biquadfilt_toss_fetch(susp, snd_list) + register biquadfilt_susp_type susp; + snd_list_type snd_list; +{ + long final_count = susp->susp.toss_cnt; + time_type final_time = susp->susp.t0; + long n; + + /* fetch samples from s up to final_time for this block of zeros */ + while ((round((final_time - susp->s->t0) * susp->s->sr)) >= + susp->s->current) + susp_get_samples(s, s_ptr, s_cnt); + /* convert to normal processing when we hit final_count */ + /* we want each signal positioned at final_time */ + n = round((final_time - susp->s->t0) * susp->s->sr - + (susp->s->current - susp->s_cnt)); + susp->s_ptr += n; + susp_took(s_cnt, n); + susp->susp.fetch = susp->susp.keep_fetch; + (*(susp->susp.fetch))(susp, snd_list); +} + + +void biquadfilt_mark(biquadfilt_susp_type susp) +{ + sound_xlmark(susp->s); +} + + +void biquadfilt_free(biquadfilt_susp_type susp) +{ + sound_unref(susp->s); + ffree_generic(susp, sizeof(biquadfilt_susp_node), "biquadfilt_free"); +} + + +void biquadfilt_print_tree(biquadfilt_susp_type susp, int n) +{ + indent(n); + stdputstr("s:"); + sound_print_tree_1(susp->s, n); +} + + +sound_type snd_make_biquadfilt(sound_type s, double b0, double b1, double b2, double a1, double a2, double z1init, double z2init) +{ + register biquadfilt_susp_type susp; + rate_type sr = s->sr; + time_type t0 = s->t0; + int interp_desc = 0; + sample_type scale_factor = 1.0F; + time_type t0_min = t0; + falloc_generic(susp, biquadfilt_susp_node, "snd_make_biquadfilt"); + susp->z1 = z1init; + susp->z2 = z2init; + susp->b0 = b0; + susp->b1 = b1; + susp->b2 = b2; + susp->a1 = a1; + susp->a2 = a2; + + /* select a susp fn based on sample rates */ + interp_desc = (interp_desc << 2) + interp_style(s, sr); + switch (interp_desc) { + case INTERP_n: susp->susp.fetch = biquadfilt_n_fetch; break; + case INTERP_s: susp->susp.fetch = biquadfilt_s_fetch; break; + default: snd_badsr(); break; + } + + susp->terminate_cnt = UNKNOWN; + /* handle unequal start times, if any */ + if (t0 < s->t0) sound_prepend_zeros(s, t0); + /* minimum start time over all inputs: */ + t0_min = min(s->t0, t0); + /* how many samples to toss before t0: */ + susp->susp.toss_cnt = (long) ((t0 - t0_min) * sr + 0.5); + if (susp->susp.toss_cnt > 0) { + susp->susp.keep_fetch = susp->susp.fetch; + susp->susp.fetch = biquadfilt_toss_fetch; + } + + /* initialize susp state */ + susp->susp.free = biquadfilt_free; + susp->susp.sr = sr; + susp->susp.t0 = t0; + susp->susp.mark = biquadfilt_mark; + susp->susp.print_tree = biquadfilt_print_tree; + susp->susp.name = "biquadfilt"; + susp->logically_stopped = false; + susp->susp.log_stop_cnt = logical_stop_cnt_cvt(s); + susp->susp.current = 0; + susp->s = s; + susp->s_cnt = 0; + return sound_create((snd_susp_type)susp, t0, sr, scale_factor); +} + + +sound_type snd_biquadfilt(sound_type s, double b0, double b1, double b2, double a1, double a2, double z1init, double z2init) +{ + sound_type s_copy = sound_copy(s); + return snd_make_biquadfilt(s_copy, b0, b1, b2, a1, a2, z1init, z2init); +} |