gstreamer/gst/subenc/gstwebvttenc.c

277 lines
8.3 KiB
C

/* GStreamer
* Copyright (C) <2008> Thijs Vermeir <thijsvermeir@gmail.com>
* Copyright (C) 2011 David Schleef <ds@schleef.org>
*
* 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.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "string.h"
#include "gstwebvttenc.h"
#include <gst/controller/gstcontroller.h>
GST_DEBUG_CATEGORY_STATIC (webvttenc_debug);
#define GST_CAT_DEFAULT webvttenc_debug
enum
{
ARG_0,
ARG_TIMESTAMP,
ARG_DURATION
};
static GstStaticPadTemplate src_template = GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("text/webvtt"));
static GstStaticPadTemplate sink_template = GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("text/plain; text/x-pango-markup"));
static GstFlowReturn gst_webvtt_enc_chain (GstPad * pad, GstBuffer * buf);
static gchar *gst_webvtt_enc_timeconvertion (GstWebvttEnc * webvttenc,
GstBuffer * buf);
static gchar *gst_webvtt_enc_timestamp_to_string (GstClockTime timestamp);
static void gst_webvtt_enc_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec);
static void gst_webvtt_enc_reset (GstWebvttEnc * webvttenc);
static void gst_webvtt_enc_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec);
GST_BOILERPLATE (GstWebvttEnc, gst_webvtt_enc, GstElement, GST_TYPE_ELEMENT);
static gchar *
gst_webvtt_enc_timestamp_to_string (GstClockTime timestamp)
{
guint h, m, s, ms;
h = timestamp / (3600 * GST_SECOND);
timestamp -= h * 3600 * GST_SECOND;
m = timestamp / (60 * GST_SECOND);
timestamp -= m * 60 * GST_SECOND;
s = timestamp / GST_SECOND;
timestamp -= s * GST_SECOND;
ms = timestamp / GST_MSECOND;
return g_strdup_printf ("%02d:%02d:%02d.%03d", h, m, s, ms);
}
static gchar *
gst_webvtt_enc_timeconvertion (GstWebvttEnc * webvttenc, GstBuffer * buf)
{
gchar *start_time;
gchar *stop_time;
gchar *string;
start_time = gst_webvtt_enc_timestamp_to_string (GST_BUFFER_TIMESTAMP (buf) +
webvttenc->timestamp);
if (GST_CLOCK_TIME_IS_VALID (GST_BUFFER_DURATION (buf))) {
stop_time = gst_webvtt_enc_timestamp_to_string (GST_BUFFER_TIMESTAMP (buf) +
webvttenc->timestamp + GST_BUFFER_DURATION (buf) + webvttenc->duration);
} else {
stop_time = gst_webvtt_enc_timestamp_to_string (GST_BUFFER_TIMESTAMP (buf) +
webvttenc->timestamp + webvttenc->duration);
}
string = g_strdup_printf ("%s --> %s\n", start_time, stop_time);
g_free (start_time);
g_free (stop_time);
return string;
}
static GstFlowReturn
gst_webvtt_enc_chain (GstPad * pad, GstBuffer * buf)
{
GstWebvttEnc *webvttenc;
GstBuffer *new_buffer;
gchar *timing;
GstFlowReturn ret;
webvttenc = GST_WEBVTT_ENC (gst_pad_get_parent_element (pad));
if (!webvttenc->pushed_header) {
const char *header = "WEBVTT\n\n";
new_buffer = gst_buffer_new_and_alloc (strlen (header));
memcpy (GST_BUFFER_DATA (new_buffer), header, strlen (header));
GST_BUFFER_TIMESTAMP (new_buffer) = GST_CLOCK_TIME_NONE;
GST_BUFFER_DURATION (new_buffer) = GST_CLOCK_TIME_NONE;
ret = gst_pad_push (webvttenc->srcpad, new_buffer);
if (ret != GST_FLOW_OK) {
goto out;
}
webvttenc->pushed_header = TRUE;
}
gst_object_sync_values (GST_OBJECT (webvttenc), GST_BUFFER_TIMESTAMP (buf));
timing = gst_webvtt_enc_timeconvertion (webvttenc, buf);
new_buffer =
gst_buffer_new_and_alloc (strlen (timing) + GST_BUFFER_SIZE (buf) + 1);
memcpy (GST_BUFFER_DATA (new_buffer), timing, strlen (timing));
memcpy (GST_BUFFER_DATA (new_buffer) + strlen (timing), GST_BUFFER_DATA (buf),
GST_BUFFER_SIZE (buf));
memcpy (GST_BUFFER_DATA (new_buffer) + GST_BUFFER_SIZE (new_buffer) - 1,
"\n", 1);
g_free (timing);
GST_BUFFER_TIMESTAMP (new_buffer) = GST_BUFFER_TIMESTAMP (buf);
GST_BUFFER_DURATION (new_buffer) = GST_BUFFER_DURATION (buf);
ret = gst_pad_push (webvttenc->srcpad, new_buffer);
out:
gst_buffer_unref (buf);
gst_object_unref (webvttenc);
return ret;
}
static void
gst_webvtt_enc_base_init (gpointer klass)
{
GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&sink_template));
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&src_template));
gst_element_class_set_metadata (element_class,
"WebVTT encoder", "Codec/Encoder/Subtitle",
"WebVTT subtitle encoder", "David Schleef <ds@schleef.org>");
}
static void
gst_webvtt_enc_reset (GstWebvttEnc * webvttenc)
{
webvttenc->counter = 1;
}
static GstStateChangeReturn
gst_webvtt_enc_change_state (GstElement * element, GstStateChange transition)
{
GstStateChangeReturn ret;
GstWebvttEnc *webvttenc = GST_WEBVTT_ENC (element);
ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
if (ret == GST_STATE_CHANGE_FAILURE)
return ret;
switch (transition) {
case GST_STATE_CHANGE_PAUSED_TO_READY:
gst_webvtt_enc_reset (webvttenc);
break;
default:
break;
}
return ret;
}
static void
gst_webvtt_enc_get_property (GObject * object,
guint prop_id, GValue * value, GParamSpec * pspec)
{
GstWebvttEnc *webvttenc;
webvttenc = GST_WEBVTT_ENC (object);
switch (prop_id) {
case ARG_TIMESTAMP:
g_value_set_int64 (value, webvttenc->timestamp);
break;
case ARG_DURATION:
g_value_set_int64 (value, webvttenc->duration);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_webvtt_enc_set_property (GObject * object,
guint prop_id, const GValue * value, GParamSpec * pspec)
{
GstWebvttEnc *webvttenc;
webvttenc = GST_WEBVTT_ENC (object);
switch (prop_id) {
case ARG_TIMESTAMP:
webvttenc->timestamp = g_value_get_int64 (value);
break;
case ARG_DURATION:
webvttenc->duration = g_value_get_int64 (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_webvtt_enc_class_init (GstWebvttEncClass * klass)
{
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
gobject_class->set_property = GST_DEBUG_FUNCPTR (gst_webvtt_enc_set_property);
gobject_class->get_property = GST_DEBUG_FUNCPTR (gst_webvtt_enc_get_property);
element_class->change_state = GST_DEBUG_FUNCPTR (gst_webvtt_enc_change_state);
g_object_class_install_property (gobject_class, ARG_TIMESTAMP,
g_param_spec_int64 ("timestamp", "Offset for the starttime",
"Offset for the starttime for the subtitles", G_MININT64, G_MAXINT64,
0,
G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, ARG_DURATION,
g_param_spec_int64 ("duration", "Offset for the duration",
"Offset for the duration of the subtitles", G_MININT64, G_MAXINT64,
0,
G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE | G_PARAM_STATIC_STRINGS));
GST_DEBUG_CATEGORY_INIT (webvttenc_debug, "webvttenc", 0,
"SubRip subtitle encoder");
}
static void
gst_webvtt_enc_init (GstWebvttEnc * webvttenc, GstWebvttEncClass * klass)
{
gst_webvtt_enc_reset (webvttenc);
webvttenc->srcpad = gst_pad_new_from_static_template (&src_template, "src");
gst_element_add_pad (GST_ELEMENT (webvttenc), webvttenc->srcpad);
webvttenc->sinkpad =
gst_pad_new_from_static_template (&sink_template, "sink");
gst_element_add_pad (GST_ELEMENT (webvttenc), webvttenc->sinkpad);
gst_pad_set_chain_function (webvttenc->sinkpad, gst_webvtt_enc_chain);
}