mpv/audio/filter/af_scaletempo.c

582 lines
17 KiB
C

/*
* scaletempo audio filter
*
* scale tempo while maintaining pitch
* (WSOLA technique with cross correlation)
* inspired by SoundTouch library by Olli Parviainen
*
* basic algorithm
* - produce 'stride' output samples per loop
* - consume stride*scale input samples per loop
*
* to produce smoother transitions between strides, blend next overlap
* samples from last stride with correlated samples of current input
*
* Copyright (c) 2007 Robert Juliano
*
* This file is part of MPlayer.
*
* MPlayer is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* MPlayer 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with MPlayer; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include <stdlib.h>
#include <string.h>
#include <limits.h>
#include <assert.h>
#include "af.h"
#include "libavutil/common.h"
#include "core/subopt-helper.h"
// Data for specific instances of this filter
typedef struct af_scaletempo_s
{
// stride
float scale;
float speed;
float frames_stride_scaled;
float frames_stride_error;
int bytes_per_frame;
int bytes_stride;
float bytes_stride_scaled;
int bytes_queue;
int bytes_queued;
int bytes_to_slide;
int8_t* buf_queue;
// overlap
int samples_overlap;
int samples_standing;
int bytes_overlap;
int bytes_standing;
void* buf_overlap;
void* table_blend;
void (*output_overlap)(struct af_scaletempo_s* s, void* out_buf, int bytes_off);
// best overlap
int frames_search;
int num_channels;
void* buf_pre_corr;
void* table_window;
int (*best_overlap_offset)(struct af_scaletempo_s* s);
// command line
float scale_nominal;
float ms_stride;
float percent_overlap;
float ms_search;
short speed_tempo;
short speed_pitch;
} af_scaletempo_t;
static int fill_queue(struct af_instance* af, struct mp_audio* data, int offset)
{
af_scaletempo_t* s = af->setup;
int bytes_in = data->len - offset;
int offset_unchanged = offset;
if (s->bytes_to_slide > 0) {
if (s->bytes_to_slide < s->bytes_queued) {
int bytes_move = s->bytes_queued - s->bytes_to_slide;
memmove(s->buf_queue,
s->buf_queue + s->bytes_to_slide,
bytes_move);
s->bytes_to_slide = 0;
s->bytes_queued = bytes_move;
} else {
int bytes_skip;
s->bytes_to_slide -= s->bytes_queued;
bytes_skip = FFMIN(s->bytes_to_slide, bytes_in);
s->bytes_queued = 0;
s->bytes_to_slide -= bytes_skip;
offset += bytes_skip;
bytes_in -= bytes_skip;
}
}
if (bytes_in > 0) {
int bytes_copy = FFMIN(s->bytes_queue - s->bytes_queued, bytes_in);
assert(bytes_copy >= 0);
memcpy(s->buf_queue + s->bytes_queued,
(int8_t*)data->audio + offset,
bytes_copy);
s->bytes_queued += bytes_copy;
offset += bytes_copy;
}
return offset - offset_unchanged;
}
#define UNROLL_PADDING (4*4)
static int best_overlap_offset_float(af_scaletempo_t* s)
{
float *pw, *po, *ppc, *search_start;
float best_corr = INT_MIN;
int best_off = 0;
int i, off;
pw = s->table_window;
po = s->buf_overlap;
po += s->num_channels;
ppc = s->buf_pre_corr;
for (i=s->num_channels; i<s->samples_overlap; i++) {
*ppc++ = *pw++ * *po++;
}
search_start = (float*)s->buf_queue + s->num_channels;
for (off=0; off<s->frames_search; off++) {
float corr = 0;
float* ps = search_start;
ppc = s->buf_pre_corr;
for (i=s->num_channels; i<s->samples_overlap; i++) {
corr += *ppc++ * *ps++;
}
if (corr > best_corr) {
best_corr = corr;
best_off = off;
}
search_start += s->num_channels;
}
return best_off * 4 * s->num_channels;
}
static int best_overlap_offset_s16(af_scaletempo_t* s)
{
int32_t *pw, *ppc;
int16_t *po, *search_start;
int64_t best_corr = INT64_MIN;
int best_off = 0;
int off;
long i;
pw = s->table_window;
po = s->buf_overlap;
po += s->num_channels;
ppc = s->buf_pre_corr;
for (i=s->num_channels; i<s->samples_overlap; i++) {
*ppc++ = ( *pw++ * *po++ ) >> 15;
}
search_start = (int16_t*)s->buf_queue + s->num_channels;
for (off=0; off<s->frames_search; off++) {
int64_t corr = 0;
int16_t* ps = search_start;
ppc = s->buf_pre_corr;
ppc += s->samples_overlap - s->num_channels;
ps += s->samples_overlap - s->num_channels;
i = -(s->samples_overlap - s->num_channels);
do {
corr += ppc[i+0] * ps[i+0];
corr += ppc[i+1] * ps[i+1];
corr += ppc[i+2] * ps[i+2];
corr += ppc[i+3] * ps[i+3];
i += 4;
} while (i < 0);
if (corr > best_corr) {
best_corr = corr;
best_off = off;
}
search_start += s->num_channels;
}
return best_off * 2 * s->num_channels;
}
static void output_overlap_float(af_scaletempo_t* s, void* buf_out,
int bytes_off)
{
float* pout = buf_out;
float* pb = s->table_blend;
float* po = s->buf_overlap;
float* pin = (float*)(s->buf_queue + bytes_off);
int i;
for (i=0; i<s->samples_overlap; i++) {
*pout++ = *po - *pb++ * ( *po - *pin++ ); po++;
}
}
static void output_overlap_s16(af_scaletempo_t* s, void* buf_out,
int bytes_off)
{
int16_t* pout = buf_out;
int32_t* pb = s->table_blend;
int16_t* po = s->buf_overlap;
int16_t* pin = (int16_t*)(s->buf_queue + bytes_off);
int i;
for (i=0; i<s->samples_overlap; i++) {
*pout++ = *po - ( ( *pb++ * ( *po - *pin++ ) ) >> 16 ); po++;
}
}
// Filter data through filter
static struct mp_audio* play(struct af_instance* af, struct mp_audio* data)
{
af_scaletempo_t* s = af->setup;
int offset_in;
int max_bytes_out;
int8_t* pout;
if (s->scale == 1.0) {
af->delay = 0;
return data;
}
// RESIZE_LOCAL_BUFFER - can't use macro
max_bytes_out = ((int)(data->len / s->bytes_stride_scaled) + 1) * s->bytes_stride;
if (max_bytes_out > af->data->len) {
mp_msg(MSGT_AFILTER, MSGL_V, "[libaf] Reallocating memory in module %s, "
"old len = %i, new len = %i\n",af->info->name,af->data->len,max_bytes_out);
af->data->audio = realloc(af->data->audio, max_bytes_out);
if (!af->data->audio) {
mp_msg(MSGT_AFILTER, MSGL_FATAL, "[libaf] Could not allocate memory\n");
return NULL;
}
af->data->len = max_bytes_out;
}
offset_in = fill_queue(af, data, 0);
pout = af->data->audio;
while (s->bytes_queued >= s->bytes_queue) {
int ti;
float tf;
int bytes_off = 0;
// output stride
if (s->output_overlap) {
if (s->best_overlap_offset)
bytes_off = s->best_overlap_offset(s);
s->output_overlap(s, pout, bytes_off);
}
memcpy(pout + s->bytes_overlap,
s->buf_queue + bytes_off + s->bytes_overlap,
s->bytes_standing);
pout += s->bytes_stride;
// input stride
memcpy(s->buf_overlap,
s->buf_queue + bytes_off + s->bytes_stride,
s->bytes_overlap);
tf = s->frames_stride_scaled + s->frames_stride_error;
ti = (int)tf;
s->frames_stride_error = tf - ti;
s->bytes_to_slide = ti * s->bytes_per_frame;
offset_in += fill_queue(af, data, offset_in);
}
// This filter can have a negative delay when scale > 1:
// output corresponding to some length of input can be decided and written
// after receiving only a part of that input.
af->delay = s->bytes_queued - s->bytes_to_slide;
data->audio = af->data->audio;
data->len = pout - (int8_t *)af->data->audio;
return data;
}
// Initialization and runtime control
static int control(struct af_instance* af, int cmd, void* arg)
{
af_scaletempo_t* s = af->setup;
switch(cmd){
case AF_CONTROL_REINIT:{
struct mp_audio* data = (struct mp_audio*)arg;
float srate = data->rate / 1000;
int nch = data->nch;
int bps;
int use_int = 0;
int frames_stride, frames_overlap;
int i, j;
mp_msg(MSGT_AFILTER, MSGL_V,
"[scaletempo] %.3f speed * %.3f scale_nominal = %.3f\n",
s->speed, s->scale_nominal, s->scale);
if (s->scale == 1.0) {
if (s->speed_tempo && s->speed_pitch)
return AF_DETACH;
memcpy(af->data, data, sizeof(struct mp_audio));
af->delay = 0;
af->mul = 1;
return af_test_output(af, data);
}
af->data->rate = data->rate;
af->data->nch = data->nch;
if ( data->format == AF_FORMAT_S16_LE
|| data->format == AF_FORMAT_S16_BE ) {
use_int = 1;
af->data->format = AF_FORMAT_S16_NE;
af->data->bps = bps = 2;
} else {
af->data->format = AF_FORMAT_FLOAT_NE;
af->data->bps = bps = 4;
}
frames_stride = srate * s->ms_stride;
s->bytes_stride = frames_stride * bps * nch;
s->bytes_stride_scaled = s->scale * s->bytes_stride;
s->frames_stride_scaled = s->scale * frames_stride;
s->frames_stride_error = 0;
af->mul = (double)s->bytes_stride / s->bytes_stride_scaled;
af->delay = 0;
frames_overlap = frames_stride * s->percent_overlap;
if (frames_overlap <= 0) {
s->bytes_standing = s->bytes_stride;
s->samples_standing = s->bytes_standing / bps;
s->output_overlap = NULL;
s->bytes_overlap = 0;
} else {
s->samples_overlap = frames_overlap * nch;
s->bytes_overlap = frames_overlap * nch * bps;
s->bytes_standing = s->bytes_stride - s->bytes_overlap;
s->samples_standing = s->bytes_standing / bps;
s->buf_overlap = realloc(s->buf_overlap, s->bytes_overlap);
s->table_blend = realloc(s->table_blend, s->bytes_overlap * 4);
if(!s->buf_overlap || !s->table_blend) {
mp_msg(MSGT_AFILTER, MSGL_FATAL, "[scaletempo] Out of memory\n");
return AF_ERROR;
}
memset(s->buf_overlap, 0, s->bytes_overlap);
if (use_int) {
int32_t* pb = s->table_blend;
int64_t blend = 0;
for (i=0; i<frames_overlap; i++) {
int32_t v = blend / frames_overlap;
for (j=0; j<nch; j++) {
*pb++ = v;
}
blend += 65536; // 2^16
}
s->output_overlap = output_overlap_s16;
} else {
float* pb = s->table_blend;
for (i=0; i<frames_overlap; i++) {
float v = i / (float)frames_overlap;
for (j=0; j<nch; j++) {
*pb++ = v;
}
}
s->output_overlap = output_overlap_float;
}
}
s->frames_search = (frames_overlap > 1) ? srate * s->ms_search : 0;
if (s->frames_search <= 0) {
s->best_overlap_offset = NULL;
} else {
if (use_int) {
int64_t t = frames_overlap;
int32_t n = 8589934588LL / (t * t); // 4 * (2^31 - 1) / t^2
int32_t* pw;
s->buf_pre_corr = realloc(s->buf_pre_corr, s->bytes_overlap * 2 + UNROLL_PADDING);
s->table_window = realloc(s->table_window, s->bytes_overlap * 2 - nch * bps * 2);
if(!s->buf_pre_corr || !s->table_window) {
mp_msg(MSGT_AFILTER, MSGL_FATAL, "[scaletempo] Out of memory\n");
return AF_ERROR;
}
memset((char *)s->buf_pre_corr + s->bytes_overlap * 2, 0, UNROLL_PADDING);
pw = s->table_window;
for (i=1; i<frames_overlap; i++) {
int32_t v = ( i * (t - i) * n ) >> 15;
for (j=0; j<nch; j++) {
*pw++ = v;
}
}
s->best_overlap_offset = best_overlap_offset_s16;
} else {
float* pw;
s->buf_pre_corr = realloc(s->buf_pre_corr, s->bytes_overlap);
s->table_window = realloc(s->table_window, s->bytes_overlap - nch * bps);
if(!s->buf_pre_corr || !s->table_window) {
mp_msg(MSGT_AFILTER, MSGL_FATAL, "[scaletempo] Out of memory\n");
return AF_ERROR;
}
pw = s->table_window;
for (i=1; i<frames_overlap; i++) {
float v = i * (frames_overlap - i);
for (j=0; j<nch; j++) {
*pw++ = v;
}
}
s->best_overlap_offset = best_overlap_offset_float;
}
}
s->bytes_per_frame = bps * nch;
s->num_channels = nch;
s->bytes_queue
= (s->frames_search + frames_stride + frames_overlap) * bps * nch;
s->buf_queue = realloc(s->buf_queue, s->bytes_queue + UNROLL_PADDING);
if(!s->buf_queue) {
mp_msg(MSGT_AFILTER, MSGL_FATAL, "[scaletempo] Out of memory\n");
return AF_ERROR;
}
s->bytes_queued = 0;
s->bytes_to_slide = 0;
mp_msg (MSGT_AFILTER, MSGL_DBG2, "[scaletempo] "
"%.2f stride_in, %i stride_out, %i standing, "
"%i overlap, %i search, %i queue, %s mode\n",
s->frames_stride_scaled,
(int)(s->bytes_stride / nch / bps),
(int)(s->bytes_standing / nch / bps),
(int)(s->bytes_overlap / nch / bps),
s->frames_search,
(int)(s->bytes_queue / nch / bps),
(use_int?"s16":"float"));
return af_test_output(af, (struct mp_audio*)arg);
}
case AF_CONTROL_PLAYBACK_SPEED | AF_CONTROL_SET:{
if (s->speed_tempo) {
if (s->speed_pitch) {
break;
}
s->speed = *(float*)arg;
s->scale = s->speed * s->scale_nominal;
} else {
if (s->speed_pitch) {
s->speed = 1 / *(float*)arg;
s->scale = s->speed * s->scale_nominal;
break;
}
}
return AF_OK;
}
case AF_CONTROL_SCALETEMPO_AMOUNT | AF_CONTROL_SET:{
s->scale = *(float*)arg;
s->scale = s->speed * s->scale_nominal;
return AF_OK;
}
case AF_CONTROL_SCALETEMPO_AMOUNT | AF_CONTROL_GET:
*(float*)arg = s->scale;
return AF_OK;
case AF_CONTROL_COMMAND_LINE:{
strarg_t speed = {};
opt_t subopts[] = {
{"scale", OPT_ARG_FLOAT, &s->scale_nominal, NULL},
{"stride", OPT_ARG_FLOAT, &s->ms_stride, NULL},
{"overlap", OPT_ARG_FLOAT, &s->percent_overlap, NULL},
{"search", OPT_ARG_FLOAT, &s->ms_search, NULL},
{"speed", OPT_ARG_STR, &speed, NULL},
{NULL},
};
if (subopt_parse(arg, subopts) != 0) {
return AF_ERROR;
}
if (s->scale_nominal <= 0) {
mp_msg(MSGT_AFILTER, MSGL_ERR, "[scaletempo] %s: %s: scale > 0\n",
mp_gtext("error parsing command line"),
mp_gtext("value out of range"));
return AF_ERROR;
}
if (s->ms_stride <= 0) {
mp_msg(MSGT_AFILTER, MSGL_ERR, "[scaletempo] %s: %s: stride > 0\n",
mp_gtext("error parsing command line"),
mp_gtext("value out of range"));
return AF_ERROR;
}
if (s->percent_overlap < 0 || s->percent_overlap > 1) {
mp_msg(MSGT_AFILTER, MSGL_ERR,
"[scaletempo] %s: %s: 0 <= overlap <= 1\n",
mp_gtext("error parsing command line"),
mp_gtext("value out of range"));
return AF_ERROR;
}
if (s->ms_search < 0) {
mp_msg(MSGT_AFILTER, MSGL_ERR, "[scaletempo] %s: %s: search >= 0\n",
mp_gtext("error parsing command line"),
mp_gtext("value out of range"));
return AF_ERROR;
}
if (speed.len > 0) {
if (strcmp(speed.str, "pitch") == 0) {
s->speed_tempo = 0;
s->speed_pitch = 1;
} else if (strcmp(speed.str, "tempo") == 0) {
s->speed_tempo = 1;
s->speed_pitch = 0;
} else if (strcmp(speed.str, "none") == 0) {
s->speed_tempo = 0;
s->speed_pitch = 0;
} else if (strcmp(speed.str, "both") == 0) {
s->speed_tempo = 1;
s->speed_pitch = 1;
} else {
mp_msg(MSGT_AFILTER, MSGL_ERR,
"[scaletempo] %s: %s: speed=[pitch|tempo|none|both]\n",
mp_gtext("error parsing command line"),
mp_gtext("value out of range"));
return AF_ERROR;
}
}
s->scale = s->speed * s->scale_nominal;
mp_msg(MSGT_AFILTER, MSGL_DBG2, "[scaletempo] %6.3f scale, %6.2f stride, %6.2f overlap, %6.2f search, speed = %s\n", s->scale_nominal, s->ms_stride, s->percent_overlap, s->ms_search, (s->speed_tempo?(s->speed_pitch?"tempo and speed":"tempo"):(s->speed_pitch?"pitch":"none")));
return AF_OK;
}
}
return AF_UNKNOWN;
}
// Deallocate memory
static void uninit(struct af_instance* af)
{
af_scaletempo_t* s = af->setup;
free(af->data->audio);
free(af->data);
free(s->buf_queue);
free(s->buf_overlap);
free(s->buf_pre_corr);
free(s->table_blend);
free(s->table_window);
free(af->setup);
}
// Allocate memory and set function pointers
static int af_open(struct af_instance* af){
af_scaletempo_t* s;
af->control = control;
af->uninit = uninit;
af->play = play;
af->mul = 1;
af->data = calloc(1,sizeof(struct mp_audio));
af->setup = calloc(1,sizeof(af_scaletempo_t));
if(af->data == NULL || af->setup == NULL)
return AF_ERROR;
s = af->setup;
s->scale = s->speed = s->scale_nominal = 1.0;
s->speed_tempo = 1;
s->speed_pitch = 0;
s->ms_stride = 60;
s->percent_overlap = .20;
s->ms_search = 14;
return AF_OK;
}
// Description of this filter
struct af_info af_info_scaletempo = {
"Scale audio tempo while maintaining pitch",
"scaletempo",
"Robert Juliano",
"",
AF_FLAGS_REENTRANT,
af_open
};