mirror of
https://github.com/cookiengineer/audacity
synced 2025-05-05 14:18:53 +02:00
50 lines
1.8 KiB
Plaintext
50 lines
1.8 KiB
Plaintext
(SAMPLER-ALG
|
|
(NAME "sampler")
|
|
(ARGUMENTS ("sound_type" "s") ("double" "step") ("double" "loop_start")
|
|
("rate_type" "sr") ("double" "hz") ("time_type" "t0") ("sound_type" "s_fm")
|
|
("long" "npoints"))
|
|
(TABLE "s")
|
|
(NOT-IN-INNER-LOOP "s")
|
|
(STATE
|
|
("double" "loop_to" "loop_start * s->sr")
|
|
("table_type" "the_table" "sound_to_table(s)")
|
|
("sample_type *" "table_ptr" "susp->the_table->samples")
|
|
("double" "table_len" "susp->the_table->length;
|
|
{ long index = (long) susp->loop_to;
|
|
double frac = susp->loop_to - index;
|
|
if (index > round(susp->table_len) ||
|
|
index < 0) {
|
|
index = 0;
|
|
frac = 0;
|
|
}
|
|
susp->table_ptr[round(susp->table_len)] = /* copy interpolated start to last entry */
|
|
(sample_type) (susp->table_ptr[index] * (1.0 - frac) +
|
|
susp->table_ptr[index + 1] * frac);}")
|
|
("double" "phase" "0.0")
|
|
("double" "ph_incr" "(s->sr / sr) * hz / step_to_hz(step);
|
|
s_fm->scale = (sample_type) (s_fm->scale * (susp->ph_incr / hz))") )
|
|
|
|
(ALWAYS-SCALE s_fm)
|
|
(INLINE-INTERPOLATION T) ; so that modulation can be low frequency
|
|
(STEP-FUNCTION s_fm)
|
|
(TERMINATE (MIN s_fm))
|
|
(LOGICAL-STOP (MIN s_fm))
|
|
(INNER-LOOP-LOCALS " long table_index;
|
|
double x1;
|
|
")
|
|
(INNER-LOOP "table_index = (long) phase;
|
|
x1 = table_ptr[table_index];
|
|
output = (sample_type) (x1 + (phase - table_index) *
|
|
(table_ptr[table_index + 1] - x1));
|
|
phase += ph_incr + s_fm;
|
|
while (phase > table_len) phase -= (table_len - loop_to);
|
|
/* watch out for negative frequencies! */
|
|
if (phase < 0) phase = 0")
|
|
(CONSTANT "ph_incr" "table_len" "table_ptr" "loop_to")
|
|
|
|
(SAMPLE-RATE "sr")
|
|
(FINALIZATION " table_unref(susp->the_table);
|
|
")
|
|
)
|
|
|