gstreamer/gst/scaletempo/gstscaletempo.c
Stefan Kost 266a57d77b scaletempo: improve the docs
Fix the syntax, add more explanation and xref the properties.
2011-07-08 00:11:37 -07:00

749 lines
23 KiB
C

/*
* GStreamer
* Copyright (C) 2008 Rov Juvano <rovjuvano@users.sourceforge.net>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/**
* SECTION:element-scaletempo
*
* Scale tempo while maintaining pitch
* (WSOLA-like technique with cross correlation)
* Inspired by SoundTouch library by Olli Parviainen
*
* Use Sceletempo to apply playback rates without the chipmunk effect.
*
* <refsect2>
* <title>Example pipelines</title>
* <para>
* |[
* filesrc location=media.ext ! decodebin name=d \
* d. ! queue ! audioconvert ! audioresample ! scaletempo ! audioconvert ! audioresample ! autoaudiosink \
* d. ! queue ! ffmpegcolorspace ! autovideosink
* ]|
* OR
* |[
* playbin uri=... audio_sink="scaletempo ! audioconvert ! audioresample ! autoaudiosink"
* ]|
* When an application sends a seek event with rate != 1.0, Scaletempo applies
* the rate change by scaling the tempo without scaling the pitch.
*
* Scaletempo works by producing audio in constant sized chunks
* (#GstScaletempo:stride) but consuming chunks proportional to the playback
* rate.
*
* Scaletempo then smooths the output by blending the end of one stride with
* the next (#GstScaletempo:overlap).
*
* Scaletempo smooths the overlap further by searching within the input buffer
* for the best overlap position. Scaletempo uses a statistical cross
* correlation (roughly a dot-product). Scaletempo consumes most of its CPU
* cycles here. One can use the #GstScaletempo:search propery to tune how far
* the algoritm looks.
* </para>
* </refsect2>
*/
/*
* Note: frame = audio key unit (i.e. one sample for each channel)
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <gst/gst.h>
#include <gst/base/gstbasetransform.h>
#include <string.h> /* for memset */
#include "gstscaletempo.h"
GST_DEBUG_CATEGORY_STATIC (gst_scaletempo_debug);
#define GST_CAT_DEFAULT gst_scaletempo_debug
/* Filter signals and args */
enum
{
LAST_SIGNAL
};
enum
{
PROP_0,
PROP_RATE,
PROP_STRIDE,
PROP_OVERLAP,
PROP_SEARCH,
};
#define SUPPORTED_CAPS \
GST_STATIC_CAPS ( \
"audio/x-raw-float, " \
"rate = (int) [ 1, MAX ], " \
"channels = (int) [ 1, MAX ], " \
"endianness = (int) BYTE_ORDER, " \
"width = (int) 32;" \
"audio/x-raw-int, " \
"rate = (int) [ 1, MAX ], " \
"channels = (int) [ 1, MAX ], " \
"endianness = (int) BYTE_ORDER, " \
"width = (int) 16, " \
"depth = (int) 16, " \
"signed = (boolean) true;" \
)
static GstStaticPadTemplate sink_template = GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
SUPPORTED_CAPS);
static GstStaticPadTemplate src_template = GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC,
GST_PAD_ALWAYS,
SUPPORTED_CAPS);
#define DEBUG_INIT(bla) GST_DEBUG_CATEGORY_INIT (gst_scaletempo_debug, "scaletempo", 0, "scaletempo element");
GST_BOILERPLATE_FULL (GstScaletempo, gst_scaletempo, GstBaseTransform,
GST_TYPE_BASE_TRANSFORM, DEBUG_INIT);
typedef struct _GstScaletempoPrivate
{
gdouble scale;
/* parameters */
guint ms_stride;
gdouble percent_overlap;
guint ms_search;
/* caps */
gboolean use_int;
guint samples_per_frame; /* AKA number of channels */
guint bytes_per_sample;
guint bytes_per_frame;
guint sample_rate;
/* stride */
gdouble frames_stride_scaled;
gdouble frames_stride_error;
guint bytes_stride;
gdouble bytes_stride_scaled;
guint bytes_queue_max;
guint bytes_queued;
guint bytes_to_slide;
gint8 *buf_queue;
/* overlap */
guint samples_overlap;
guint samples_standing;
guint bytes_overlap;
guint bytes_standing;
gpointer buf_overlap;
gpointer table_blend;
void (*output_overlap) (GstScaletempo * scaletempo, gpointer out_buf,
guint bytes_off);
/* best overlap */
guint frames_search;
gpointer buf_pre_corr;
gpointer table_window;
guint (*best_overlap_offset) (GstScaletempo * scaletempo);
/* gstreamer */
gint64 segment_start;
/* threads */
gboolean reinit_buffers;
} GstScaletempoPrivate;
#define GST_SCALETEMPO_GET_PRIVATE(o) (G_TYPE_INSTANCE_GET_PRIVATE ((o), GST_TYPE_SCALETEMPO, GstScaletempoPrivate))
static guint
best_overlap_offset_float (GstScaletempo * scaletempo)
{
GstScaletempoPrivate *p = GST_SCALETEMPO_GET_PRIVATE (scaletempo);
gfloat *pw, *po, *ppc, *search_start;
gfloat best_corr = G_MININT;
guint best_off = 0;
gint i, off;
pw = p->table_window;
po = p->buf_overlap;
po += p->samples_per_frame;
ppc = p->buf_pre_corr;
for (i = p->samples_per_frame; i < p->samples_overlap; i++) {
*ppc++ = *pw++ * *po++;
}
search_start = (gfloat *) p->buf_queue + p->samples_per_frame;
for (off = 0; off < p->frames_search; off++) {
gfloat corr = 0;
gfloat *ps = search_start;
ppc = p->buf_pre_corr;
for (i = p->samples_per_frame; i < p->samples_overlap; i++) {
corr += *ppc++ * *ps++;
}
if (corr > best_corr) {
best_corr = corr;
best_off = off;
}
search_start += p->samples_per_frame;
}
return best_off * p->bytes_per_frame;
}
/* buffer padding for loop optimization: sizeof(gint32) * (loop_size - 1) */
#define UNROLL_PADDING (4*3)
static guint
best_overlap_offset_s16 (GstScaletempo * scaletempo)
{
GstScaletempoPrivate *p = GST_SCALETEMPO_GET_PRIVATE (scaletempo);
gint32 *pw, *ppc;
gint16 *po, *search_start;
gint64 best_corr = G_MININT64;
guint best_off = 0;
guint off;
glong i;
pw = p->table_window;
po = p->buf_overlap;
po += p->samples_per_frame;
ppc = p->buf_pre_corr;
for (i = p->samples_per_frame; i < p->samples_overlap; i++) {
*ppc++ = (*pw++ * *po++) >> 15;
}
search_start = (gint16 *) p->buf_queue + p->samples_per_frame;
for (off = 0; off < p->frames_search; off++) {
gint64 corr = 0;
gint16 *ps = search_start;
ppc = p->buf_pre_corr;
ppc += p->samples_overlap - p->samples_per_frame;
ps += p->samples_overlap - p->samples_per_frame;
i = -((glong) p->samples_overlap - (glong) p->samples_per_frame);
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 += p->samples_per_frame;
}
return best_off * p->bytes_per_frame;
}
static void
output_overlap_float (GstScaletempo * scaletempo,
gpointer buf_out, guint bytes_off)
{
GstScaletempoPrivate *p = GST_SCALETEMPO_GET_PRIVATE (scaletempo);
gfloat *pout = buf_out;
gfloat *pb = p->table_blend;
gfloat *po = p->buf_overlap;
gfloat *pin = (gfloat *) (p->buf_queue + bytes_off);
gint i;
for (i = 0; i < p->samples_overlap; i++) {
*pout++ = *po - *pb++ * (*po - *pin++);
po++;
}
}
static void
output_overlap_s16 (GstScaletempo * scaletempo,
gpointer buf_out, guint bytes_off)
{
GstScaletempoPrivate *p = GST_SCALETEMPO_GET_PRIVATE (scaletempo);
gint16 *pout = buf_out;
gint32 *pb = p->table_blend;
gint16 *po = p->buf_overlap;
gint16 *pin = (gint16 *) (p->buf_queue + bytes_off);
gint i;
for (i = 0; i < p->samples_overlap; i++) {
*pout++ = *po - ((*pb++ * (*po - *pin++)) >> 16);
po++;
}
}
static guint
fill_queue (GstScaletempo * scaletempo, GstBuffer * buf_in, guint offset)
{
GstScaletempoPrivate *p = GST_SCALETEMPO_GET_PRIVATE (scaletempo);
guint bytes_in = GST_BUFFER_SIZE (buf_in) - offset;
guint offset_unchanged = offset;
if (p->bytes_to_slide > 0) {
if (p->bytes_to_slide < p->bytes_queued) {
guint bytes_in_move = p->bytes_queued - p->bytes_to_slide;
memmove (p->buf_queue, p->buf_queue + p->bytes_to_slide, bytes_in_move);
p->bytes_to_slide = 0;
p->bytes_queued = bytes_in_move;
} else {
guint bytes_in_skip;
p->bytes_to_slide -= p->bytes_queued;
bytes_in_skip = MIN (p->bytes_to_slide, bytes_in);
p->bytes_queued = 0;
p->bytes_to_slide -= bytes_in_skip;
offset += bytes_in_skip;
bytes_in -= bytes_in_skip;
}
}
if (bytes_in > 0) {
guint bytes_in_copy = MIN (p->bytes_queue_max - p->bytes_queued, bytes_in);
memcpy (p->buf_queue + p->bytes_queued,
GST_BUFFER_DATA (buf_in) + offset, bytes_in_copy);
p->bytes_queued += bytes_in_copy;
offset += bytes_in_copy;
}
return offset - offset_unchanged;
}
static void
reinit_buffers (GstScaletempo * scaletempo)
{
GstScaletempoPrivate *p = GST_SCALETEMPO_GET_PRIVATE (scaletempo);
gint i, j;
guint frames_overlap;
guint new_size;
guint frames_stride = p->ms_stride * p->sample_rate / 1000.0;
p->bytes_stride = frames_stride * p->bytes_per_frame;
/* overlap */
frames_overlap = frames_stride * p->percent_overlap;
if (frames_overlap < 1) { /* if no overlap */
p->bytes_overlap = 0;
p->bytes_standing = p->bytes_stride;
p->samples_standing = p->bytes_standing / p->bytes_per_sample;
p->output_overlap = NULL;
} else {
guint prev_overlap = p->bytes_overlap;
p->bytes_overlap = frames_overlap * p->bytes_per_frame;
p->samples_overlap = frames_overlap * p->samples_per_frame;
p->bytes_standing = p->bytes_stride - p->bytes_overlap;
p->samples_standing = p->bytes_standing / p->bytes_per_sample;
p->buf_overlap = g_realloc (p->buf_overlap, p->bytes_overlap);
p->table_blend = g_realloc (p->table_blend, p->samples_overlap * 4); /* sizeof (gint32|gfloat) */
if (p->bytes_overlap > prev_overlap) {
memset ((guint8 *) p->buf_overlap + prev_overlap, 0,
p->bytes_overlap - prev_overlap);
}
if (p->use_int) {
gint32 *pb = p->table_blend;
gint64 blend = 0;
for (i = 0; i < frames_overlap; i++) {
gint32 v = blend / frames_overlap;
for (j = 0; j < p->samples_per_frame; j++) {
*pb++ = v;
}
blend += 65535; /* 2^16 */
}
p->output_overlap = output_overlap_s16;
} else {
gfloat *pb = p->table_blend;
gfloat t = (gfloat) frames_overlap;
for (i = 0; i < frames_overlap; i++) {
gfloat v = i / t;
for (j = 0; j < p->samples_per_frame; j++) {
*pb++ = v;
}
}
p->output_overlap = output_overlap_float;
}
}
/* best overlap */
p->frames_search =
(frames_overlap <= 1) ? 0 : p->ms_search * p->sample_rate / 1000.0;
if (p->frames_search < 1) { /* if no search */
p->best_overlap_offset = NULL;
} else {
guint bytes_pre_corr = (p->samples_overlap - p->samples_per_frame) * 4; /* sizeof (gint32|gfloat) */
p->buf_pre_corr =
g_realloc (p->buf_pre_corr, bytes_pre_corr + UNROLL_PADDING);
p->table_window = g_realloc (p->table_window, bytes_pre_corr);
if (p->use_int) {
gint64 t = frames_overlap;
gint32 n = 8589934588LL / (t * t); /* 4 * (2^31 - 1) / t^2 */
gint32 *pw;
memset ((guint8 *) p->buf_pre_corr + bytes_pre_corr, 0, UNROLL_PADDING);
pw = p->table_window;
for (i = 1; i < frames_overlap; i++) {
gint32 v = (i * (t - i) * n) >> 15;
for (j = 0; j < p->samples_per_frame; j++) {
*pw++ = v;
}
}
p->best_overlap_offset = best_overlap_offset_s16;
} else {
gfloat *pw = p->table_window;
for (i = 1; i < frames_overlap; i++) {
gfloat v = i * (frames_overlap - i);
for (j = 0; j < p->samples_per_frame; j++) {
*pw++ = v;
}
}
p->best_overlap_offset = best_overlap_offset_float;
}
}
new_size =
(p->frames_search + frames_stride + frames_overlap) * p->bytes_per_frame;
if (p->bytes_queued > new_size) {
if (p->bytes_to_slide > p->bytes_queued) {
p->bytes_to_slide -= p->bytes_queued;
p->bytes_queued = 0;
} else {
guint new_queued = MIN (p->bytes_queued - p->bytes_to_slide, new_size);
memmove (p->buf_queue,
p->buf_queue + p->bytes_queued - new_queued, new_queued);
p->bytes_to_slide = 0;
p->bytes_queued = new_queued;
}
}
p->bytes_queue_max = new_size;
p->buf_queue = g_realloc (p->buf_queue, p->bytes_queue_max);
p->bytes_stride_scaled = p->bytes_stride * p->scale;
p->frames_stride_scaled = p->bytes_stride_scaled / p->bytes_per_frame;
GST_DEBUG
("%.3f scale, %.3f stride_in, %i stride_out, %i standing, %i overlap, %i search, %i queue, %s mode",
p->scale, p->frames_stride_scaled,
(gint) (p->bytes_stride / p->bytes_per_frame),
(gint) (p->bytes_standing / p->bytes_per_frame),
(gint) (p->bytes_overlap / p->bytes_per_frame), p->frames_search,
(gint) (p->bytes_queue_max / p->bytes_per_frame),
(p->use_int ? "s16" : "float"));
p->reinit_buffers = FALSE;
}
/* GstBaseTransform vmethod implementations */
static GstFlowReturn
gst_scaletempo_transform (GstBaseTransform * trans,
GstBuffer * inbuf, GstBuffer * outbuf)
{
GstScaletempo *scaletempo = GST_SCALETEMPO (trans);
GstScaletempoPrivate *p = GST_SCALETEMPO_GET_PRIVATE (scaletempo);
gint8 *pout = (gint8 *) GST_BUFFER_DATA (outbuf);
guint offset_in = fill_queue (scaletempo, inbuf, 0);
guint bytes_out = 0;
while (p->bytes_queued >= p->bytes_queue_max) {
guint bytes_off = 0;
gdouble frames_to_slide;
guint frames_to_stride_whole;
// output stride
if (p->output_overlap) {
if (p->best_overlap_offset) {
bytes_off = p->best_overlap_offset (scaletempo);
}
p->output_overlap (scaletempo, pout, bytes_off);
}
memcpy (pout + p->bytes_overlap,
p->buf_queue + bytes_off + p->bytes_overlap, p->bytes_standing);
pout += p->bytes_stride;
bytes_out += p->bytes_stride;
// input stride
memcpy (p->buf_overlap,
p->buf_queue + bytes_off + p->bytes_stride, p->bytes_overlap);
frames_to_slide = p->frames_stride_scaled + p->frames_stride_error;
frames_to_stride_whole = (gint) frames_to_slide;
p->bytes_to_slide = frames_to_stride_whole * p->bytes_per_frame;
p->frames_stride_error = frames_to_slide - frames_to_stride_whole;
offset_in += fill_queue (scaletempo, inbuf, offset_in);
}
GST_BUFFER_SIZE (outbuf) = bytes_out;
GST_BUFFER_TIMESTAMP (outbuf) =
(GST_BUFFER_TIMESTAMP (outbuf) - p->segment_start) / p->scale +
p->segment_start;
//GST_BUFFER_DURATION (outbuf) = bytes_out * GST_SECOND / (p->bytes_per_frame * p->sample_rate);
return GST_FLOW_OK;
}
static gboolean
gst_scaletempo_transform_size (GstBaseTransform * trans,
GstPadDirection direction,
GstCaps * caps, guint size, GstCaps * othercaps, guint * othersize)
{
if (direction == GST_PAD_SINK) {
GstScaletempo *scaletempo = GST_SCALETEMPO (trans);
GstScaletempoPrivate *priv = GST_SCALETEMPO_GET_PRIVATE (scaletempo);
gint bytes_to_out;
if (priv->reinit_buffers)
reinit_buffers (scaletempo);
bytes_to_out = size + priv->bytes_queued - priv->bytes_to_slide;
if (bytes_to_out < (gint) priv->bytes_queue_max) {
*othersize = 0;
} else {
/* while (total_buffered - stride_length * n >= queue_max) n++ */
*othersize = priv->bytes_stride * ((guint) (
(bytes_to_out - priv->bytes_queue_max +
/* rounding protection */ priv->bytes_per_frame)
/ priv->bytes_stride_scaled) + 1);
}
return TRUE;
}
return FALSE;
}
static gboolean
gst_scaletempo_sink_event (GstBaseTransform * trans, GstEvent * event)
{
if (GST_EVENT_TYPE (event) == GST_EVENT_NEWSEGMENT) {
GstScaletempo *scaletempo = GST_SCALETEMPO (trans);
GstScaletempoPrivate *priv = GST_SCALETEMPO_GET_PRIVATE (scaletempo);
gboolean update;
gdouble rate, applied_rate;
GstFormat format;
gint64 start, stop, position;
gst_event_parse_new_segment_full (event, &update, &rate, &applied_rate,
&format, &start, &stop, &position);
if (priv->scale != rate) {
if (ABS (rate - 1.0) < 1e-10) {
priv->scale = 1.0;
gst_base_transform_set_passthrough (GST_BASE_TRANSFORM (scaletempo),
TRUE);
} else {
gst_base_transform_set_passthrough (GST_BASE_TRANSFORM (scaletempo),
FALSE);
priv->scale = rate;
priv->bytes_stride_scaled = priv->bytes_stride * priv->scale;
priv->frames_stride_scaled =
priv->bytes_stride_scaled / priv->bytes_per_frame;
GST_DEBUG ("%.3f scale, %.3f stride_in, %i stride_out", priv->scale,
priv->frames_stride_scaled,
(gint) (priv->bytes_stride / priv->bytes_per_frame));
priv->bytes_to_slide = 0;
}
}
if (priv->scale != 1.0) {
priv->segment_start = start;
applied_rate = priv->scale;
rate = 1.0;
//gst_event_unref (event);
if (stop != -1) {
stop = (stop - start) / applied_rate + start;
}
event = gst_event_new_new_segment_full (update, rate, applied_rate,
format, start, stop, position);
gst_pad_push_event (GST_BASE_TRANSFORM_SRC_PAD (trans), event);
return FALSE;
}
}
return parent_class->event (trans, event);
}
static gboolean
gst_scaletempo_set_caps (GstBaseTransform * trans,
GstCaps * incaps, GstCaps * outcaps)
{
GstScaletempo *scaletempo = GST_SCALETEMPO (trans);
GstScaletempoPrivate *priv = GST_SCALETEMPO_GET_PRIVATE (scaletempo);
GstStructure *s = gst_caps_get_structure (incaps, 0);
gint width, bps, nch, rate;
gboolean use_int;
const gchar *type = gst_structure_get_name (s);
if (g_str_equal (type, "audio/x-raw-int")) {
use_int = TRUE;
gst_structure_get_int (s, "depth", &width);
} else if (g_str_equal (type, "audio/x-raw-float")) {
use_int = FALSE;
gst_structure_get_int (s, "width", &width);
} else {
return FALSE;
}
bps = width / 8;
gst_structure_get_int (s, "channels", &nch);
gst_structure_get_int (s, "rate", &rate);
GST_DEBUG ("caps: %s seek, "
"%5" G_GUINT32_FORMAT " rate, "
"%2" G_GUINT32_FORMAT " nch, "
"%2" G_GUINT32_FORMAT " bps", type, rate, nch, bps);
if (rate != priv->sample_rate
|| nch != priv->samples_per_frame
|| bps != priv->bytes_per_sample || use_int != priv->use_int) {
priv->sample_rate = rate;
priv->samples_per_frame = nch;
priv->bytes_per_sample = bps;
priv->bytes_per_frame = nch * bps;
priv->use_int = use_int;
priv->reinit_buffers = TRUE;
}
return TRUE;
}
/* GObject vmethod implementations */
static void
gst_scaletempo_get_property (GObject * object,
guint prop_id, GValue * value, GParamSpec * pspec)
{
GstScaletempo *scaletempo = GST_SCALETEMPO (object);
GstScaletempoPrivate *priv = GST_SCALETEMPO_GET_PRIVATE (scaletempo);
switch (prop_id) {
case PROP_RATE:
g_value_set_double (value, priv->scale);
break;
case PROP_STRIDE:
g_value_set_uint (value, priv->ms_stride);
break;
case PROP_OVERLAP:
g_value_set_double (value, priv->percent_overlap);
break;
case PROP_SEARCH:
g_value_set_uint (value, priv->ms_search);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_scaletempo_set_property (GObject * object,
guint prop_id, const GValue * value, GParamSpec * pspec)
{
GstScaletempo *scaletempo = GST_SCALETEMPO (object);
GstScaletempoPrivate *priv = GST_SCALETEMPO_GET_PRIVATE (scaletempo);
switch (prop_id) {
case PROP_STRIDE:{
guint new_value = g_value_get_uint (value);
if (priv->ms_stride != new_value) {
priv->ms_stride = new_value;
priv->reinit_buffers = TRUE;
}
break;
}
case PROP_OVERLAP:{
gdouble new_value = g_value_get_double (value);
if (priv->percent_overlap != new_value) {
priv->percent_overlap = new_value;
priv->reinit_buffers = TRUE;
}
break;
}
case PROP_SEARCH:{
guint new_value = g_value_get_uint (value);
if (priv->ms_search != new_value) {
priv->ms_search = new_value;
priv->reinit_buffers = TRUE;
}
break;
}
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_scaletempo_base_init (gpointer klass)
{
GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&src_template));
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&sink_template));
gst_element_class_set_details_simple (element_class, "Scaletempo",
"Filter/Effect/Rate",
"Sync audio tempo with playback rate",
"Rov Juvano <rovjuvano@users.sourceforge.net>");
}
static void
gst_scaletempo_class_init (GstScaletempoClass * klass)
{
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
GstBaseTransformClass *basetransform_class = GST_BASE_TRANSFORM_CLASS (klass);
g_type_class_add_private (klass, sizeof (GstScaletempoPrivate));
gobject_class->get_property = GST_DEBUG_FUNCPTR (gst_scaletempo_get_property);
gobject_class->set_property = GST_DEBUG_FUNCPTR (gst_scaletempo_set_property);
g_object_class_install_property (gobject_class, PROP_RATE,
g_param_spec_double ("rate", "Playback Rate", "Current playback rate",
G_MININT, G_MAXINT, 1.0, G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_STRIDE,
g_param_spec_uint ("stride", "Stride Length",
"Length in milliseconds to output each stride", 1, 5000, 30,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_OVERLAP,
g_param_spec_double ("overlap", "Overlap Length",
"Percentage of stride to overlap", 0, 1, .2,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_SEARCH,
g_param_spec_uint ("search", "Search Length",
"Length in milliseconds to search for best overlap position", 0, 500,
14, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
basetransform_class->event = GST_DEBUG_FUNCPTR (gst_scaletempo_sink_event);
basetransform_class->set_caps = GST_DEBUG_FUNCPTR (gst_scaletempo_set_caps);
basetransform_class->transform_size =
GST_DEBUG_FUNCPTR (gst_scaletempo_transform_size);
basetransform_class->transform = GST_DEBUG_FUNCPTR (gst_scaletempo_transform);
}
static void
gst_scaletempo_init (GstScaletempo * scaletempo, GstScaletempoClass * klass)
{
GstScaletempoPrivate *priv = GST_SCALETEMPO_GET_PRIVATE (scaletempo);
/* defaults */
priv->ms_stride = 30;
priv->percent_overlap = .2;
priv->ms_search = 14;
/* uninitialized */
priv->scale = 0;
priv->sample_rate = 0;
priv->frames_stride_error = 0;
priv->bytes_stride = 0;
priv->bytes_queued = 0;
priv->bytes_to_slide = 0;
priv->segment_start = 0;
}