ref: ceffff92190351bc83dc94fbfb72dc31a481ceea
dir: /src/tempo.c/
/* libSoX effect: change tempo (and duration) or pitch (maintain duration) * Copyright (c) 2007,8 robs@users.sourceforge.net * Based on ideas from Olli Parviainen's SoundTouch Library. * * This library is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as published by * the Free Software Foundation; either version 2.1 of the License, or (at * your option) any later version. * * This library is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser * General Public License for more details. * * You should have received a copy of the GNU Lesser General Public License * along with this library; if not, write to the Free Software Foundation, * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include "sox_i.h" #include "fifo.h" #include <math.h> typedef struct { /* Configuration parameters: */ size_t channels; sox_bool quick_search; /* Whether to quick search or linear search */ double factor; /* 1 for no change, < 1 for slower, > 1 for faster. */ size_t search; /* Wide samples to search for best overlap position */ size_t segment; /* Processing segment length in wide samples */ size_t overlap; /* In wide samples */ size_t process_size; /* # input wide samples needed to process 1 segment */ /* Buffers: */ fifo_t input_fifo; float * overlap_buf; fifo_t output_fifo; /* Counters: */ uint64_t samples_in; uint64_t samples_out; uint64_t segments_total; uint64_t skip_total; } tempo_t; /* Waveform Similarity by least squares; works across multi-channels */ static float difference(const float * a, const float * b, size_t length) { float diff = 0; size_t i = 0; #define _ diff += sqr(a[i] - b[i]), ++i; /* Loop optimisation */ do {_ _ _ _ _ _ _ _} while (i < length); /* N.B. length ≡ 0 (mod 8) */ #undef _ return diff; } /* Find where the two segments are most alike over the overlap period. */ static size_t tempo_best_overlap_position(tempo_t * t, float const * new_win) { float * f = t->overlap_buf; size_t j, best_pos, prev_best_pos = (t->search + 1) >> 1, step = 64; size_t i = best_pos = t->quick_search? prev_best_pos : 0; float diff, least_diff = difference(new_win + t->channels * i, f, t->channels * t->overlap); int k = 0; if (t->quick_search) do { /* hierarchical search */ for (k = -1; k <= 1; k += 2) for (j = 1; j < 4 || step == 64; ++j) { i = prev_best_pos + k * j * step; if ((int)i < 0 || i >= t->search) break; diff = difference(new_win + t->channels * i, f, t->channels * t->overlap); if (diff < least_diff) least_diff = diff, best_pos = i; } prev_best_pos = best_pos; } while (step >>= 2); else for (i = 1; i < t->search; i++) { /* linear search */ diff = difference(new_win + t->channels * i, f, t->channels * t->overlap); if (diff < least_diff) least_diff = diff, best_pos = i; } return best_pos; } static void tempo_overlap( tempo_t * t, const float * in1, const float * in2, float * output) { size_t i, j, k = 0; float fade_step = 1.0f / (float) t->overlap; for (i = 0; i < t->overlap; ++i) { float fade_in = fade_step * (float) i; float fade_out = 1.0f - fade_in; for (j = 0; j < t->channels; ++j, ++k) output[k] = in1[k] * fade_out + in2[k] * fade_in; } } static void tempo_process(tempo_t * t) { while (fifo_occupancy(&t->input_fifo) >= t->process_size) { size_t skip, offset; /* Copy or overlap the first bit to the output */ if (!t->segments_total) { offset = t->search / 2; fifo_write(&t->output_fifo, t->overlap, (float *) fifo_read_ptr(&t->input_fifo) + t->channels * offset); } else { offset = tempo_best_overlap_position(t, fifo_read_ptr(&t->input_fifo)); tempo_overlap(t, t->overlap_buf, (float *) fifo_read_ptr(&t->input_fifo) + t->channels * offset, fifo_write(&t->output_fifo, t->overlap, NULL)); } /* Copy the middle bit to the output */ fifo_write(&t->output_fifo, t->segment - 2 * t->overlap, (float *) fifo_read_ptr(&t->input_fifo) + t->channels * (offset + t->overlap)); /* Copy the end bit to overlap_buf ready to be mixed with * the beginning of the next segment. */ memcpy(t->overlap_buf, (float *) fifo_read_ptr(&t->input_fifo) + t->channels * (offset + t->segment - t->overlap), t->channels * t->overlap * sizeof(*(t->overlap_buf))); /* Advance through the input stream */ skip = t->factor * (++t->segments_total * (t->segment - t->overlap)) + 0.5; t->skip_total += skip -= t->skip_total; fifo_read(&t->input_fifo, skip, NULL); } } static float * tempo_input(tempo_t * t, float const * samples, size_t n) { t->samples_in += n; return fifo_write(&t->input_fifo, n, samples); } static float const * tempo_output(tempo_t * t, float * samples, size_t * n) { t->samples_out += *n = min(*n, fifo_occupancy(&t->output_fifo)); return fifo_read(&t->output_fifo, *n, samples); } /* Flush samples remaining in overlap_buf & input_fifo to the output. */ static void tempo_flush(tempo_t * t) { uint64_t samples_out = t->samples_in / t->factor + .5; size_t remaining = samples_out > t->samples_out ? (size_t)(samples_out - t->samples_out) : 0; float * buff = lsx_calloc(128 * t->channels, sizeof(*buff)); if (remaining > 0) { while (fifo_occupancy(&t->output_fifo) < remaining) { tempo_input(t, buff, (size_t) 128); tempo_process(t); } fifo_trim_to(&t->output_fifo, remaining); t->samples_in = 0; } free(buff); } static void tempo_setup(tempo_t * t, double sample_rate, sox_bool quick_search, double factor, double segment_ms, double search_ms, double overlap_ms) { size_t max_skip; t->quick_search = quick_search; t->factor = factor; t->segment = sample_rate * segment_ms / 1000 + .5; t->search = sample_rate * search_ms / 1000 + .5; t->overlap = max(sample_rate * overlap_ms / 1000 + 4.5, 16); t->overlap &= ~7; /* Make divisible by 8 for loop optimisation */ if (t->overlap * 2 > t->segment) t->overlap -= 8; t->overlap_buf = lsx_malloc(t->overlap * t->channels * sizeof(*t->overlap_buf)); max_skip = ceil(factor * (t->segment - t->overlap)); t->process_size = max(max_skip + t->overlap, t->segment) + t->search; memset(fifo_reserve(&t->input_fifo, t->search / 2), 0, (t->search / 2) * t->channels * sizeof(float)); } static void tempo_delete(tempo_t * t) { free(t->overlap_buf); fifo_delete(&t->output_fifo); fifo_delete(&t->input_fifo); free(t); } static tempo_t * tempo_create(size_t channels) { tempo_t * t = lsx_calloc(1, sizeof(*t)); t->channels = channels; fifo_create(&t->input_fifo, t->channels * sizeof(float)); fifo_create(&t->output_fifo, t->channels * sizeof(float)); return t; } /*------------------------------- SoX Wrapper --------------------------------*/ typedef struct { tempo_t * tempo; sox_bool quick_search; double factor, segment_ms, search_ms, overlap_ms; } priv_t; static int getopts(sox_effect_t * effp, int argc, char **argv) { priv_t * p = (priv_t *)effp->priv; enum {Default, Music, Speech, Linear} profile = Default; static const double segments_ms [] = { 82,82, 35 , 20}; static const double segments_pow[] = { 0, 1, .33 , 1}; static const double overlaps_div[] = {6.833, 7, 2.5 , 2}; static const double searches_div[] = {5.587, 6, 2.14, 2}; int c; lsx_getopt_t optstate; lsx_getopt_init(argc, argv, "+qmls", NULL, lsx_getopt_flag_none, 1, &optstate); p->segment_ms = p->search_ms = p->overlap_ms = HUGE_VAL; while ((c = lsx_getopt(&optstate)) != -1) switch (c) { case 'q': p->quick_search = sox_true; break; case 'm': profile = Music; break; case 's': profile = Speech; break; case 'l': profile = Linear; p->search_ms = 0; break; default: lsx_fail("unknown option `-%c'", optstate.opt); return lsx_usage(effp); } argc -= optstate.ind, argv += optstate.ind; do { /* break-able block */ NUMERIC_PARAMETER(factor ,0.1 , 100 ) NUMERIC_PARAMETER(segment_ms , 10 , 120) NUMERIC_PARAMETER(search_ms , 0 , 30 ) NUMERIC_PARAMETER(overlap_ms , 0 , 30 ) } while (0); if (p->segment_ms == HUGE_VAL) p->segment_ms = max(10, segments_ms[profile] / max(pow(p->factor, segments_pow[profile]), 1)); if (p->overlap_ms == HUGE_VAL) p->overlap_ms = p->segment_ms / overlaps_div[profile]; if (p->search_ms == HUGE_VAL) p->search_ms = p->segment_ms / searches_div[profile]; p->overlap_ms = min(p->overlap_ms, p->segment_ms / 2); lsx_report("quick_search=%u factor=%g segment=%g search=%g overlap=%g", p->quick_search, p->factor, p->segment_ms, p->search_ms, p->overlap_ms); return argc? lsx_usage(effp) : SOX_SUCCESS; } static int start(sox_effect_t * effp) { priv_t * p = (priv_t *)effp->priv; if (p->factor == 1) return SOX_EFF_NULL; p->tempo = tempo_create((size_t)effp->in_signal.channels); tempo_setup(p->tempo, effp->in_signal.rate, p->quick_search, p->factor, p->segment_ms, p->search_ms, p->overlap_ms); effp->out_signal.length = SOX_UNKNOWN_LEN; if (effp->in_signal.length != SOX_UNKNOWN_LEN) { uint64_t in_length = effp->in_signal.length / effp->in_signal.channels; uint64_t out_length = in_length / p->factor + .5; effp->out_signal.length = out_length * effp->in_signal.channels; } return SOX_SUCCESS; } static int flow(sox_effect_t * effp, const sox_sample_t * ibuf, sox_sample_t * obuf, size_t * isamp, size_t * osamp) { priv_t * p = (priv_t *)effp->priv; size_t i, odone = *osamp /= effp->in_signal.channels; float const * s = tempo_output(p->tempo, NULL, &odone); SOX_SAMPLE_LOCALS; for (i = 0; i < odone * effp->in_signal.channels; ++i) *obuf++ = SOX_FLOAT_32BIT_TO_SAMPLE(*s++, effp->clips); if (*isamp && odone < *osamp) { float * t = tempo_input(p->tempo, NULL, *isamp / effp->in_signal.channels); for (i = *isamp; i; --i) *t++ = SOX_SAMPLE_TO_FLOAT_32BIT(*ibuf++, effp->clips); tempo_process(p->tempo); } else *isamp = 0; *osamp = odone * effp->in_signal.channels; return SOX_SUCCESS; } static int drain(sox_effect_t * effp, sox_sample_t * obuf, size_t * osamp) { priv_t * p = (priv_t *)effp->priv; static size_t isamp = 0; tempo_flush(p->tempo); return flow(effp, 0, obuf, &isamp, osamp); } static int stop(sox_effect_t * effp) { priv_t * p = (priv_t *)effp->priv; tempo_delete(p->tempo); return SOX_SUCCESS; } sox_effect_handler_t const * lsx_tempo_effect_fn(void) { static sox_effect_handler_t handler = { "tempo", "[-q] [-m | -s | -l] factor [segment-ms [search-ms [overlap-ms]]]", SOX_EFF_MCHAN | SOX_EFF_LENGTH, getopts, start, flow, drain, stop, NULL, sizeof(priv_t) }; return &handler; } /*---------------------------------- pitch -----------------------------------*/ static int pitch_getopts(sox_effect_t * effp, int argc, char **argv) { double d; char dummy, arg[100], **argv2 = lsx_malloc(argc * sizeof(*argv2)); int result, pos = (argc > 1 && !strcmp(argv[1], "-q"))? 2 : 1; if (argc <= pos || sscanf(argv[pos], "%lf %c", &d, &dummy) != 1) return lsx_usage(effp); d = pow(2., d / 1200); /* cents --> factor */ sprintf(arg, "%g", 1 / d); memcpy(argv2, argv, argc * sizeof(*argv2)); argv2[pos] = arg; result = getopts(effp, argc, argv2); free(argv2); return result; } static int pitch_start(sox_effect_t * effp) { priv_t * p = (priv_t *) effp->priv; int result = start(effp); effp->out_signal.rate = effp->in_signal.rate / p->factor; return result; } sox_effect_handler_t const * lsx_pitch_effect_fn(void) { static sox_effect_handler_t handler; handler = *lsx_tempo_effect_fn(); handler.name = "pitch"; handler.usage = "[-q] shift-in-cents [segment-ms [search-ms [overlap-ms]]]", handler.getopts = pitch_getopts; handler.start = pitch_start; handler.flags &= ~SOX_EFF_LENGTH; handler.flags |= SOX_EFF_RATE; return &handler; }