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-rw-r--r--tran/tapf.c619
1 files changed, 619 insertions, 0 deletions
diff --git a/tran/tapf.c b/tran/tapf.c
new file mode 100644
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--- /dev/null
+++ b/tran/tapf.c
@@ -0,0 +1,619 @@
+#include "stdio.h"
+#ifndef mips
+#include "stdlib.h"
+#endif
+#include "xlisp.h"
+#include "sound.h"
+
+#include "falloc.h"
+#include "cext.h"
+#include "tapf.h"
+
+void tapf_free();
+
+
+typedef struct tapf_susp_struct {
+ snd_susp_node susp;
+ boolean started;
+ long terminate_cnt;
+ boolean logically_stopped;
+ sound_type s1;
+ long s1_cnt;
+ sample_block_values_type s1_ptr;
+ sound_type vardelay;
+ long vardelay_cnt;
+ sample_block_values_type vardelay_ptr;
+
+ /* support for interpolation of vardelay */
+ sample_type vardelay_x1_sample;
+ double vardelay_pHaSe;
+ double vardelay_pHaSe_iNcR;
+
+ /* support for ramp between samples of vardelay */
+ double output_per_vardelay;
+ long vardelay_n;
+
+ double offset;
+ double vdscale;
+ long maxdelay;
+ long bufflen;
+ long index;
+ sample_type *buffer;
+} tapf_susp_node, *tapf_susp_type;
+
+
+void tapf_sn_fetch(register tapf_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 offset_reg;
+ register double vdscale_reg;
+ register long maxdelay_reg;
+ register long bufflen_reg;
+ register long index_reg;
+ register sample_type * buffer_reg;
+ register sample_block_values_type vardelay_ptr_reg;
+ register sample_type s1_scale_reg = susp->s1->scale;
+ register sample_block_values_type s1_ptr_reg;
+ falloc_sample_block(out, "tapf_sn_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 s1 input sample block: */
+ susp_check_term_log_samples(s1, s1_ptr, s1_cnt);
+ togo = min(togo, susp->s1_cnt);
+
+ /* don't run past the vardelay input sample block: */
+ susp_check_term_samples(vardelay, vardelay_ptr, vardelay_cnt);
+ togo = min(togo, susp->vardelay_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;
+ offset_reg = susp->offset;
+ vdscale_reg = susp->vdscale;
+ maxdelay_reg = susp->maxdelay;
+ bufflen_reg = susp->bufflen;
+ index_reg = susp->index;
+ buffer_reg = susp->buffer;
+ vardelay_ptr_reg = susp->vardelay_ptr;
+ s1_ptr_reg = susp->s1_ptr;
+ out_ptr_reg = out_ptr;
+ if (n) do { /* the inner sample computation loop */
+ long phase;
+ phase = (long) (*vardelay_ptr_reg++ * vdscale_reg + offset_reg);
+ /* now phase should give number of samples of delay */
+ if (phase < 0) phase = 0;
+ else if (phase > maxdelay_reg) phase = maxdelay_reg;
+ phase = index_reg - phase;
+ /* now phase is a location in the buffer_reg (before modulo) */
+
+ /* Time out to update the buffer_reg:
+ * this is a tricky buffer_reg: buffer_reg[0] == buffer_reg[bufflen_reg]
+ * the logical length is bufflen_reg, but the actual length
+ * is bufflen_reg + 1 to allow for a repeated sample at the
+ * end. This allows for efficient interpolation.
+ */
+ buffer_reg[index_reg++] = (s1_scale_reg * *s1_ptr_reg++);
+ if (index_reg >= bufflen_reg) {
+ index_reg = 0;
+ }
+
+ /* back to the phase calculation:
+ * use conditional instead of modulo
+ */
+ if (phase < 0) phase += bufflen_reg;
+ *out_ptr_reg++ = (sample_type) (buffer_reg[phase]);;
+ } while (--n); /* inner loop */
+
+ susp->bufflen = bufflen_reg;
+ susp->index = index_reg;
+ /* using vardelay_ptr_reg is a bad idea on RS/6000: */
+ susp->vardelay_ptr += togo;
+ /* using s1_ptr_reg is a bad idea on RS/6000: */
+ susp->s1_ptr += togo;
+ out_ptr += togo;
+ susp_took(s1_cnt, togo);
+ susp_took(vardelay_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;
+ }
+} /* tapf_sn_fetch */
+
+
+void tapf_si_fetch(register tapf_susp_type susp, snd_list_type snd_list)
+{
+ int cnt = 0; /* how many samples computed */
+ sample_type vardelay_x2_sample;
+ 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 offset_reg;
+ register double vdscale_reg;
+ register long maxdelay_reg;
+ register long bufflen_reg;
+ register long index_reg;
+ register sample_type * buffer_reg;
+ register double vardelay_pHaSe_iNcR_rEg = susp->vardelay_pHaSe_iNcR;
+ register double vardelay_pHaSe_ReG;
+ register sample_type vardelay_x1_sample_reg;
+ register sample_type s1_scale_reg = susp->s1->scale;
+ register sample_block_values_type s1_ptr_reg;
+ falloc_sample_block(out, "tapf_si_fetch");
+ out_ptr = out->samples;
+ snd_list->block = out;
+
+ /* make sure sounds are primed with first values */
+ if (!susp->started) {
+ susp->started = true;
+ susp_check_term_samples(vardelay, vardelay_ptr, vardelay_cnt);
+ susp->vardelay_x1_sample = (susp->vardelay_cnt--, *(susp->vardelay_ptr));
+ }
+
+ susp_check_term_samples(vardelay, vardelay_ptr, vardelay_cnt);
+ vardelay_x2_sample = *(susp->vardelay_ptr);
+
+ 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 s1 input sample block: */
+ susp_check_term_log_samples(s1, s1_ptr, s1_cnt);
+ togo = min(togo, susp->s1_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;
+ offset_reg = susp->offset;
+ vdscale_reg = susp->vdscale;
+ maxdelay_reg = susp->maxdelay;
+ bufflen_reg = susp->bufflen;
+ index_reg = susp->index;
+ buffer_reg = susp->buffer;
+ vardelay_pHaSe_ReG = susp->vardelay_pHaSe;
+ vardelay_x1_sample_reg = susp->vardelay_x1_sample;
+ s1_ptr_reg = susp->s1_ptr;
+ out_ptr_reg = out_ptr;
+ if (n) do { /* the inner sample computation loop */
+ long phase;
+ if (vardelay_pHaSe_ReG >= 1.0) {
+ vardelay_x1_sample_reg = vardelay_x2_sample;
+ /* pick up next sample as vardelay_x2_sample: */
+ susp->vardelay_ptr++;
+ susp_took(vardelay_cnt, 1);
+ vardelay_pHaSe_ReG -= 1.0;
+ susp_check_term_samples_break(vardelay, vardelay_ptr, vardelay_cnt, vardelay_x2_sample);
+ }
+ phase = (long) (
+ (vardelay_x1_sample_reg * (1 - vardelay_pHaSe_ReG) + vardelay_x2_sample * vardelay_pHaSe_ReG) * vdscale_reg + offset_reg);
+ /* now phase should give number of samples of delay */
+ if (phase < 0) phase = 0;
+ else if (phase > maxdelay_reg) phase = maxdelay_reg;
+ phase = index_reg - phase;
+ /* now phase is a location in the buffer_reg (before modulo) */
+
+ /* Time out to update the buffer_reg:
+ * this is a tricky buffer_reg: buffer_reg[0] == buffer_reg[bufflen_reg]
+ * the logical length is bufflen_reg, but the actual length
+ * is bufflen_reg + 1 to allow for a repeated sample at the
+ * end. This allows for efficient interpolation.
+ */
+ buffer_reg[index_reg++] = (s1_scale_reg * *s1_ptr_reg++);
+ if (index_reg >= bufflen_reg) {
+ index_reg = 0;
+ }
+
+ /* back to the phase calculation:
+ * use conditional instead of modulo
+ */
+ if (phase < 0) phase += bufflen_reg;
+ *out_ptr_reg++ = (sample_type) (buffer_reg[phase]);;
+ vardelay_pHaSe_ReG += vardelay_pHaSe_iNcR_rEg;
+ } while (--n); /* inner loop */
+
+ togo -= n;
+ susp->bufflen = bufflen_reg;
+ susp->index = index_reg;
+ susp->vardelay_pHaSe = vardelay_pHaSe_ReG;
+ susp->vardelay_x1_sample = vardelay_x1_sample_reg;
+ /* using s1_ptr_reg is a bad idea on RS/6000: */
+ susp->s1_ptr += togo;
+ out_ptr += togo;
+ susp_took(s1_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;
+ }
+} /* tapf_si_fetch */
+
+
+void tapf_sr_fetch(register tapf_susp_type susp, snd_list_type snd_list)
+{
+ int cnt = 0; /* how many samples computed */
+ sample_type vardelay_DeLtA;
+ sample_type vardelay_val;
+ sample_type vardelay_x2_sample;
+ 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 offset_reg;
+ register double vdscale_reg;
+ register long maxdelay_reg;
+ register long bufflen_reg;
+ register long index_reg;
+ register sample_type * buffer_reg;
+ register sample_type s1_scale_reg = susp->s1->scale;
+ register sample_block_values_type s1_ptr_reg;
+ falloc_sample_block(out, "tapf_sr_fetch");
+ out_ptr = out->samples;
+ snd_list->block = out;
+
+ /* make sure sounds are primed with first values */
+ if (!susp->started) {
+ susp->started = true;
+ susp->vardelay_pHaSe = 1.0;
+ }
+
+ susp_check_term_samples(vardelay, vardelay_ptr, vardelay_cnt);
+ vardelay_x2_sample = *(susp->vardelay_ptr);
+
+ 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 s1 input sample block: */
+ susp_check_term_log_samples(s1, s1_ptr, s1_cnt);
+ togo = min(togo, susp->s1_cnt);
+
+ /* grab next vardelay_x2_sample when phase goes past 1.0; */
+ /* we use vardelay_n (computed below) to avoid roundoff errors: */
+ if (susp->vardelay_n <= 0) {
+ susp->vardelay_x1_sample = vardelay_x2_sample;
+ susp->vardelay_ptr++;
+ susp_took(vardelay_cnt, 1);
+ susp->vardelay_pHaSe -= 1.0;
+ susp_check_term_samples(vardelay, vardelay_ptr, vardelay_cnt);
+ vardelay_x2_sample = *(susp->vardelay_ptr);
+ /* vardelay_n gets number of samples before phase exceeds 1.0: */
+ susp->vardelay_n = (long) ((1.0 - susp->vardelay_pHaSe) *
+ susp->output_per_vardelay);
+ }
+ togo = min(togo, susp->vardelay_n);
+ vardelay_DeLtA = (sample_type) ((vardelay_x2_sample - susp->vardelay_x1_sample) * susp->vardelay_pHaSe_iNcR);
+ vardelay_val = (sample_type) (susp->vardelay_x1_sample * (1.0 - susp->vardelay_pHaSe) +
+ vardelay_x2_sample * susp->vardelay_pHaSe);
+
+ /* 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;
+ offset_reg = susp->offset;
+ vdscale_reg = susp->vdscale;
+ maxdelay_reg = susp->maxdelay;
+ bufflen_reg = susp->bufflen;
+ index_reg = susp->index;
+ buffer_reg = susp->buffer;
+ s1_ptr_reg = susp->s1_ptr;
+ out_ptr_reg = out_ptr;
+ if (n) do { /* the inner sample computation loop */
+ long phase;
+ phase = (long) (vardelay_val * vdscale_reg + offset_reg);
+ /* now phase should give number of samples of delay */
+ if (phase < 0) phase = 0;
+ else if (phase > maxdelay_reg) phase = maxdelay_reg;
+ phase = index_reg - phase;
+ /* now phase is a location in the buffer_reg (before modulo) */
+
+ /* Time out to update the buffer_reg:
+ * this is a tricky buffer_reg: buffer_reg[0] == buffer_reg[bufflen_reg]
+ * the logical length is bufflen_reg, but the actual length
+ * is bufflen_reg + 1 to allow for a repeated sample at the
+ * end. This allows for efficient interpolation.
+ */
+ buffer_reg[index_reg++] = (s1_scale_reg * *s1_ptr_reg++);
+ if (index_reg >= bufflen_reg) {
+ index_reg = 0;
+ }
+
+ /* back to the phase calculation:
+ * use conditional instead of modulo
+ */
+ if (phase < 0) phase += bufflen_reg;
+ *out_ptr_reg++ = (sample_type) (buffer_reg[phase]);;
+ vardelay_val += vardelay_DeLtA;
+ } while (--n); /* inner loop */
+
+ susp->bufflen = bufflen_reg;
+ susp->index = index_reg;
+ /* using s1_ptr_reg is a bad idea on RS/6000: */
+ susp->s1_ptr += togo;
+ out_ptr += togo;
+ susp_took(s1_cnt, togo);
+ susp->vardelay_pHaSe += togo * susp->vardelay_pHaSe_iNcR;
+ susp->vardelay_n -= 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;
+ }
+} /* tapf_sr_fetch */
+
+
+void tapf_toss_fetch(susp, snd_list)
+ register tapf_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 s1 up to final_time for this block of zeros */
+ while ((round((final_time - susp->s1->t0) * susp->s1->sr)) >=
+ susp->s1->current)
+ susp_get_samples(s1, s1_ptr, s1_cnt);
+ /* fetch samples from vardelay up to final_time for this block of zeros */
+ while ((round((final_time - susp->vardelay->t0) * susp->vardelay->sr)) >=
+ susp->vardelay->current)
+ susp_get_samples(vardelay, vardelay_ptr, vardelay_cnt);
+ /* convert to normal processing when we hit final_count */
+ /* we want each signal positioned at final_time */
+ n = round((final_time - susp->s1->t0) * susp->s1->sr -
+ (susp->s1->current - susp->s1_cnt));
+ susp->s1_ptr += n;
+ susp_took(s1_cnt, n);
+ n = round((final_time - susp->vardelay->t0) * susp->vardelay->sr -
+ (susp->vardelay->current - susp->vardelay_cnt));
+ susp->vardelay_ptr += n;
+ susp_took(vardelay_cnt, n);
+ susp->susp.fetch = susp->susp.keep_fetch;
+ (*(susp->susp.fetch))(susp, snd_list);
+}
+
+
+void tapf_mark(tapf_susp_type susp)
+{
+ sound_xlmark(susp->s1);
+ sound_xlmark(susp->vardelay);
+}
+
+
+void tapf_free(tapf_susp_type susp)
+{
+ free(susp->buffer);
+ sound_unref(susp->s1);
+ sound_unref(susp->vardelay);
+ ffree_generic(susp, sizeof(tapf_susp_node), "tapf_free");
+}
+
+
+void tapf_print_tree(tapf_susp_type susp, int n)
+{
+ indent(n);
+ stdputstr("s1:");
+ sound_print_tree_1(susp->s1, n);
+
+ indent(n);
+ stdputstr("vardelay:");
+ sound_print_tree_1(susp->vardelay, n);
+}
+
+
+sound_type snd_make_tapf(sound_type s1, double offset, sound_type vardelay, double maxdelay)
+{
+ register tapf_susp_type susp;
+ rate_type sr = s1->sr;
+ time_type t0 = max(s1->t0, vardelay->t0);
+ int interp_desc = 0;
+ sample_type scale_factor = 1.0F;
+ time_type t0_min = t0;
+ falloc_generic(susp, tapf_susp_node, "snd_make_tapf");
+ susp->offset = offset * s1->sr;
+ susp->vdscale = vardelay->scale * s1->sr;
+ susp->maxdelay = (long)(maxdelay * s1->sr);
+ susp->bufflen = max(2, (long) (susp->maxdelay + 0.5));
+ susp->index = susp->bufflen;
+ susp->buffer = (sample_type *) calloc(susp->bufflen + 1, sizeof(sample_type));
+
+ /* select a susp fn based on sample rates */
+ interp_desc = (interp_desc << 2) + interp_style(s1, sr);
+ interp_desc = (interp_desc << 2) + interp_style(vardelay, sr);
+ switch (interp_desc) {
+ case INTERP_ns: /* handled below */
+ case INTERP_nn: /* handled below */
+ case INTERP_ss: /* handled below */
+ case INTERP_sn: susp->susp.fetch = tapf_sn_fetch; break;
+ case INTERP_ni: /* handled below */
+ case INTERP_si: susp->susp.fetch = tapf_si_fetch; break;
+ case INTERP_nr: /* handled below */
+ case INTERP_sr: susp->susp.fetch = tapf_sr_fetch; break;
+ default: snd_badsr(); break;
+ }
+
+ susp->terminate_cnt = UNKNOWN;
+ /* handle unequal start times, if any */
+ if (t0 < s1->t0) sound_prepend_zeros(s1, t0);
+ if (t0 < vardelay->t0) sound_prepend_zeros(vardelay, t0);
+ /* minimum start time over all inputs: */
+ t0_min = min(s1->t0, min(vardelay->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 = tapf_toss_fetch;
+ }
+
+ /* initialize susp state */
+ susp->susp.free = tapf_free;
+ susp->susp.sr = sr;
+ susp->susp.t0 = t0;
+ susp->susp.mark = tapf_mark;
+ susp->susp.print_tree = tapf_print_tree;
+ susp->susp.name = "tapf";
+ susp->logically_stopped = false;
+ susp->susp.log_stop_cnt = logical_stop_cnt_cvt(s1);
+ susp->started = false;
+ susp->susp.current = 0;
+ susp->s1 = s1;
+ susp->s1_cnt = 0;
+ susp->vardelay = vardelay;
+ susp->vardelay_cnt = 0;
+ susp->vardelay_pHaSe = 0.0;
+ susp->vardelay_pHaSe_iNcR = vardelay->sr / sr;
+ susp->vardelay_n = 0;
+ susp->output_per_vardelay = sr / vardelay->sr;
+ return sound_create((snd_susp_type)susp, t0, sr, scale_factor);
+}
+
+
+sound_type snd_tapf(sound_type s1, double offset, sound_type vardelay, double maxdelay)
+{
+ sound_type s1_copy = sound_copy(s1);
+ sound_type vardelay_copy = sound_copy(vardelay);
+ return snd_make_tapf(s1_copy, offset, vardelay_copy, maxdelay);
+}