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gstreamer/ext/dash/gstdashdemux.c

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/*
* DASH demux plugin for GStreamer
*
* gstdashdemux.c
*
* Copyright (C) 2012 Orange
*
* Authors:
* David Corvoysier <david.corvoysier@orange.com>
* Hamid Zakari <hamid.zakari@gmail.com>
*
* Copyright (C) 2013 Smart TV Alliance
* Author: Thiago Sousa Santos <thiago.sousa.santos@collabora.com>, Collabora Ltd.
*
* 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 2.1 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library (COPYING); if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/**
* SECTION:element-dashdemux
*
* DASH demuxer element.
* <title>Example launch line</title>
* |[
* gst-launch-1.0 playbin uri="http://www-itec.uni-klu.ac.at/ftp/datasets/mmsys12/RedBullPlayStreets/redbull_4s/RedBullPlayStreets_4s_isoffmain_DIS_23009_1_v_2_1c2_2011_08_30.mpd"
* ]|
*/
/* Implementation notes:
*
* The following section describes how dashdemux works internally.
*
* Introduction:
*
* dashdemux is a "fake" demux, as unlike traditional demux elements, it
* doesn't split data streams contained in an enveloppe to expose them
* to downstream decoding elements.
*
* Instead, it parses an XML file called a manifest to identify a set of
* individual stream fragments it needs to fetch and expose to the actual
* demux elements that will handle them (this behavior is sometimes
* referred as the "demux after a demux" scenario).
*
* For a given section of content, several representations corresponding
* to different bitrates may be available: dashdemux will select the most
* appropriate representation based on local conditions (typically the
* available bandwidth and the amount of buffering available, capped by
* a maximum allowed bitrate).
*
* The representation selection algorithm can be configured using
* specific properties: max bitrate, min/max buffering, bandwidth ratio.
*
*
* General Design:
*
* dashdemux has a single sink pad that accepts the data corresponding
* to the manifest, typically fetched from an HTTP or file source.
*
* dashdemux exposes the streams it recreates based on the fragments it
* fetches through dedicated src pads corresponding to the caps of the
* fragments container (ISOBMFF/MP4 or MPEG2TS).
*
* During playback, new representations will typically be exposed as a
* new set of pads (see 'Switching between representations' below).
*
* Fragments downloading is performed using a dedicated task that fills
* an internal queue. Another task is in charge of popping fragments
* from the queue and pushing them downstream.
*
* Switching between representations:
*
* Decodebin supports scenarios allowing to seamlessly switch from one
* stream to another inside the same "decoding chain".
*
* To achieve that, it combines the elements it autoplugged in chains
* and groups, allowing only one decoding group to be active at a given
* time for a given chain.
*
* A chain can signal decodebin that it is complete by sending a
* no-more-pads event, but even after that new pads can be added to
* create new subgroups, providing that a new no-more-pads event is sent.
*
* We take advantage of that to dynamically create a new decoding group
* in order to select a different representation during playback.
*
* Typically, assuming that each fragment contains both audio and video,
* the following tree would be created:
*
* chain "DASH Demux"
* |_ group "Representation set 1"
* | |_ chain "Qt Demux 0"
* | |_ group "Stream 0"
* | |_ chain "H264"
* | |_ chain "AAC"
* |_ group "Representation set 2"
* |_ chain "Qt Demux 1"
* |_ group "Stream 1"
* |_ chain "H264"
* |_ chain "AAC"
*
* Or, if audio and video are contained in separate fragments:
*
* chain "DASH Demux"
* |_ group "Representation set 1"
* | |_ chain "Qt Demux 0"
* | | |_ group "Stream 0"
* | | |_ chain "H264"
* | |_ chain "Qt Demux 1"
* | |_ group "Stream 1"
* | |_ chain "AAC"
* |_ group "Representation set 2"
* |_ chain "Qt Demux 3"
* | |_ group "Stream 2"
* | |_ chain "H264"
* |_ chain "Qt Demux 4"
* |_ group "Stream 3"
* |_ chain "AAC"
*
* In both cases, when switching from Set 1 to Set 2 an EOS is sent on
* each end pad corresponding to Rep 0, triggering the "drain" state to
* propagate upstream.
* Once both EOS have been processed, the "Set 1" group is completely
* drained, and decodebin2 will switch to the "Set 2" group.
*
* Note: nothing can be pushed to the new decoding group before the
* old one has been drained, which means that in order to be able to
* adapt quickly to bandwidth changes, we will not be able to rely
* on downstream buffering, and will instead manage an internal queue.
*
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <inttypes.h>
#include <gio/gio.h>
#include <gst/base/gsttypefindhelper.h>
#include <gst/tag/tag.h>
#include <gst/net/gstnet.h>
#include "gst/gst-i18n-plugin.h"
#include "gstdashdemux.h"
#include "gstdash_debug.h"
static GstStaticPadTemplate gst_dash_demux_videosrc_template =
GST_STATIC_PAD_TEMPLATE ("video_%02u",
GST_PAD_SRC,
GST_PAD_SOMETIMES,
GST_STATIC_CAPS_ANY);
static GstStaticPadTemplate gst_dash_demux_audiosrc_template =
GST_STATIC_PAD_TEMPLATE ("audio_%02u",
GST_PAD_SRC,
GST_PAD_SOMETIMES,
GST_STATIC_CAPS_ANY);
static GstStaticPadTemplate gst_dash_demux_subtitlesrc_template =
GST_STATIC_PAD_TEMPLATE ("subtitle_%02u",
GST_PAD_SRC,
GST_PAD_SOMETIMES,
GST_STATIC_CAPS_ANY);
static GstStaticPadTemplate sinktemplate = GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("application/dash+xml"));
GST_DEBUG_CATEGORY (gst_dash_demux_debug);
#define GST_CAT_DEFAULT gst_dash_demux_debug
enum
{
PROP_0,
PROP_MAX_BUFFERING_TIME,
PROP_BANDWIDTH_USAGE,
PROP_MAX_BITRATE,
PROP_PRESENTATION_DELAY,
PROP_LAST
};
/* Default values for properties */
#define DEFAULT_MAX_BUFFERING_TIME 30 /* in seconds */
#define DEFAULT_BANDWIDTH_USAGE 0.8 /* 0 to 1 */
#define DEFAULT_MAX_BITRATE 24000000 /* in bit/s */
#define DEFAULT_PRESENTATION_DELAY NULL /* zero */
/* Clock drift compensation for live streams */
#define SLOW_CLOCK_UPDATE_INTERVAL (1000000 * 30 * 60) /* 30 minutes */
#define FAST_CLOCK_UPDATE_INTERVAL (1000000 * 30) /* 30 seconds */
#define SUPPORTED_CLOCK_FORMATS (GST_MPD_UTCTIMING_TYPE_NTP | GST_MPD_UTCTIMING_TYPE_HTTP_HEAD | GST_MPD_UTCTIMING_TYPE_HTTP_XSDATE | GST_MPD_UTCTIMING_TYPE_HTTP_ISO | GST_MPD_UTCTIMING_TYPE_HTTP_NTP)
#define NTP_TO_UNIX_EPOCH G_GUINT64_CONSTANT(2208988800) /* difference (in seconds) between NTP epoch and Unix epoch */
struct _GstDashDemuxClockDrift
{
GMutex clock_lock; /* used to protect access to struct */
guint selected_url;
gint64 next_update;
/* @clock_compensation: amount (in usecs) to add to client's idea of
now to map it to the server's idea of now */
GTimeSpan clock_compensation;
GstClock *ntp_clock;
};
/* GObject */
static void gst_dash_demux_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec);
static void gst_dash_demux_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec);
static void gst_dash_demux_dispose (GObject * obj);
/* GstAdaptiveDemux */
static GstClockTime gst_dash_demux_get_duration (GstAdaptiveDemux * ademux);
static gboolean gst_dash_demux_is_live (GstAdaptiveDemux * ademux);
static void gst_dash_demux_reset (GstAdaptiveDemux * ademux);
static gboolean gst_dash_demux_process_manifest (GstAdaptiveDemux * ademux,
GstBuffer * buf);
static gboolean gst_dash_demux_seek (GstAdaptiveDemux * demux, GstEvent * seek);
static GstFlowReturn
gst_dash_demux_stream_update_fragment_info (GstAdaptiveDemuxStream * stream);
static GstFlowReturn gst_dash_demux_stream_seek (GstAdaptiveDemuxStream *
stream, gboolean forward, GstSeekFlags flags, GstClockTime ts,
GstClockTime * final_ts);
static gboolean gst_dash_demux_stream_has_next_fragment (GstAdaptiveDemuxStream
* stream);
static GstFlowReturn
gst_dash_demux_stream_advance_fragment (GstAdaptiveDemuxStream * stream);
static gboolean
gst_dash_demux_stream_advance_subfragment (GstAdaptiveDemuxStream * stream);
static gboolean gst_dash_demux_stream_select_bitrate (GstAdaptiveDemuxStream *
stream, guint64 bitrate);
static gint64 gst_dash_demux_get_manifest_update_interval (GstAdaptiveDemux *
demux);
static GstFlowReturn gst_dash_demux_update_manifest_data (GstAdaptiveDemux *
demux, GstBuffer * buf);
static gint64
gst_dash_demux_stream_get_fragment_waiting_time (GstAdaptiveDemuxStream *
stream);
static void gst_dash_demux_advance_period (GstAdaptiveDemux * demux);
static gboolean gst_dash_demux_has_next_period (GstAdaptiveDemux * demux);
static GstFlowReturn gst_dash_demux_data_received (GstAdaptiveDemux * demux,
GstAdaptiveDemuxStream * stream);
static GstFlowReturn
gst_dash_demux_stream_fragment_finished (GstAdaptiveDemux * demux,
GstAdaptiveDemuxStream * stream);
/* GstDashDemux */
static gboolean gst_dash_demux_setup_all_streams (GstDashDemux * demux);
static void gst_dash_demux_stream_free (GstAdaptiveDemuxStream * stream);
static GstCaps *gst_dash_demux_get_input_caps (GstDashDemux * demux,
GstActiveStream * stream);
static GstPad *gst_dash_demux_create_pad (GstDashDemux * demux,
GstActiveStream * stream);
static GstDashDemuxClockDrift *gst_dash_demux_clock_drift_new (void);
static void gst_dash_demux_clock_drift_free (GstDashDemuxClockDrift *);
static gboolean gst_dash_demux_poll_clock_drift (GstDashDemux * demux);
static GTimeSpan gst_dash_demux_get_clock_compensation (GstDashDemux * demux);
static GDateTime *gst_dash_demux_get_server_now_utc (GstDashDemux * demux);
#define SIDX(s) (&(s)->sidx_parser.sidx)
#define SIDX_ENTRY(s,i) (&(SIDX(s)->entries[(i)]))
#define SIDX_CURRENT_ENTRY(s) SIDX_ENTRY(s, SIDX(s)->entry_index)
static void gst_dash_demux_send_content_protection_event (gpointer cp_data,
gpointer stream);
#define gst_dash_demux_parent_class parent_class
G_DEFINE_TYPE_WITH_CODE (GstDashDemux, gst_dash_demux, GST_TYPE_ADAPTIVE_DEMUX,
GST_DEBUG_CATEGORY_INIT (gst_dash_demux_debug, "dashdemux", 0,
"dashdemux element")
);
static void
gst_dash_demux_dispose (GObject * obj)
{
GstDashDemux *demux = GST_DASH_DEMUX (obj);
gst_dash_demux_reset (GST_ADAPTIVE_DEMUX_CAST (demux));
if (demux->client) {
gst_mpd_client_free (demux->client);
demux->client = NULL;
}
g_mutex_clear (&demux->client_lock);
gst_dash_demux_clock_drift_free (demux->clock_drift);
demux->clock_drift = NULL;
g_free (demux->default_presentation_delay);
G_OBJECT_CLASS (parent_class)->dispose (obj);
}
static gboolean
gst_dash_demux_get_live_seek_range (GstAdaptiveDemux * demux, gint64 * start,
gint64 * stop)
{
GstDashDemux *self = GST_DASH_DEMUX (demux);
GDateTime *now;
GDateTime *mstart;
GTimeSpan stream_now;
if (self->client->mpd_node->availabilityStartTime == NULL)
return FALSE;
now = gst_dash_demux_get_server_now_utc (self);
mstart =
gst_date_time_to_g_date_time (self->client->
mpd_node->availabilityStartTime);
stream_now = g_date_time_difference (now, mstart);
g_date_time_unref (now);
g_date_time_unref (mstart);
if (stream_now <= 0)
return FALSE;
*stop = stream_now * GST_USECOND;
if (self->client->mpd_node->timeShiftBufferDepth == GST_MPD_DURATION_NONE) {
*start = 0;
} else {
*start =
*stop - (self->client->mpd_node->timeShiftBufferDepth * GST_MSECOND);
if (*start < 0)
*start = 0;
}
return TRUE;
}
static GstClockTime
gst_dash_demux_get_presentation_offset (GstAdaptiveDemux * demux,
GstAdaptiveDemuxStream * stream)
{
GstDashDemuxStream *dashstream = (GstDashDemuxStream *) stream;
GstDashDemux *dashdemux = GST_DASH_DEMUX_CAST (demux);
return gst_mpd_parser_get_stream_presentation_offset (dashdemux->client,
dashstream->index);
}
static GstClockTime
gst_dash_demux_get_period_start_time (GstAdaptiveDemux * demux)
{
GstDashDemux *dashdemux = GST_DASH_DEMUX_CAST (demux);
return gst_mpd_parser_get_period_start_time (dashdemux->client);
}
static void
gst_dash_demux_class_init (GstDashDemuxClass * klass)
{
GObjectClass *gobject_class;
GstElementClass *gstelement_class;
GstAdaptiveDemuxClass *gstadaptivedemux_class;
gobject_class = (GObjectClass *) klass;
gstelement_class = (GstElementClass *) klass;
gstadaptivedemux_class = (GstAdaptiveDemuxClass *) klass;
gobject_class->set_property = gst_dash_demux_set_property;
gobject_class->get_property = gst_dash_demux_get_property;
gobject_class->dispose = gst_dash_demux_dispose;
#ifndef GST_REMOVE_DEPRECATED
g_object_class_install_property (gobject_class, PROP_MAX_BUFFERING_TIME,
g_param_spec_uint ("max-buffering-time", "Maximum buffering time",
"Maximum number of seconds of buffer accumulated during playback"
"(deprecated)",
2, G_MAXUINT, DEFAULT_MAX_BUFFERING_TIME,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS | G_PARAM_DEPRECATED));
g_object_class_install_property (gobject_class, PROP_BANDWIDTH_USAGE,
g_param_spec_float ("bandwidth-usage",
"Bandwidth usage [0..1]",
"Percentage of the available bandwidth to use when "
"selecting representations (deprecated)",
0, 1, DEFAULT_BANDWIDTH_USAGE,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS | G_PARAM_DEPRECATED));
#endif
g_object_class_install_property (gobject_class, PROP_MAX_BITRATE,
g_param_spec_uint ("max-bitrate", "Max bitrate",
"Max of bitrate supported by target decoder",
1000, G_MAXUINT, DEFAULT_MAX_BITRATE,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_PRESENTATION_DELAY,
g_param_spec_string ("presentation-delay", "Presentation delay",
"Default presentation delay (in seconds, milliseconds or fragments) (e.g. 12s, 2500ms, 3f)",
DEFAULT_PRESENTATION_DELAY,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
gst_element_class_add_pad_template (gstelement_class,
gst_static_pad_template_get (&gst_dash_demux_audiosrc_template));
gst_element_class_add_pad_template (gstelement_class,
gst_static_pad_template_get (&gst_dash_demux_videosrc_template));
gst_element_class_add_pad_template (gstelement_class,
gst_static_pad_template_get (&gst_dash_demux_subtitlesrc_template));
gst_element_class_add_pad_template (gstelement_class,
gst_static_pad_template_get (&sinktemplate));
gst_element_class_set_static_metadata (gstelement_class,
"DASH Demuxer",
"Codec/Demuxer/Adaptive",
"Dynamic Adaptive Streaming over HTTP demuxer",
"David Corvoysier <david.corvoysier@orange.com>\n\
Hamid Zakari <hamid.zakari@gmail.com>\n\
Gianluca Gennari <gennarone@gmail.com>");
gstadaptivedemux_class->get_duration = gst_dash_demux_get_duration;
gstadaptivedemux_class->is_live = gst_dash_demux_is_live;
gstadaptivedemux_class->reset = gst_dash_demux_reset;
gstadaptivedemux_class->seek = gst_dash_demux_seek;
gstadaptivedemux_class->process_manifest = gst_dash_demux_process_manifest;
gstadaptivedemux_class->update_manifest_data =
gst_dash_demux_update_manifest_data;
gstadaptivedemux_class->get_manifest_update_interval =
gst_dash_demux_get_manifest_update_interval;
gstadaptivedemux_class->has_next_period = gst_dash_demux_has_next_period;
gstadaptivedemux_class->advance_period = gst_dash_demux_advance_period;
gstadaptivedemux_class->stream_has_next_fragment =
gst_dash_demux_stream_has_next_fragment;
gstadaptivedemux_class->stream_advance_fragment =
gst_dash_demux_stream_advance_fragment;
gstadaptivedemux_class->stream_get_fragment_waiting_time =
gst_dash_demux_stream_get_fragment_waiting_time;
gstadaptivedemux_class->stream_seek = gst_dash_demux_stream_seek;
gstadaptivedemux_class->stream_select_bitrate =
gst_dash_demux_stream_select_bitrate;
gstadaptivedemux_class->stream_update_fragment_info =
gst_dash_demux_stream_update_fragment_info;
gstadaptivedemux_class->stream_free = gst_dash_demux_stream_free;
gstadaptivedemux_class->get_live_seek_range =
gst_dash_demux_get_live_seek_range;
gstadaptivedemux_class->get_presentation_offset =
gst_dash_demux_get_presentation_offset;
gstadaptivedemux_class->get_period_start_time =
gst_dash_demux_get_period_start_time;
gstadaptivedemux_class->finish_fragment =
gst_dash_demux_stream_fragment_finished;
gstadaptivedemux_class->data_received = gst_dash_demux_data_received;
}
static void
gst_dash_demux_init (GstDashDemux * demux)
{
/* Properties */
demux->max_buffering_time = DEFAULT_MAX_BUFFERING_TIME * GST_SECOND;
demux->max_bitrate = DEFAULT_MAX_BITRATE;
demux->default_presentation_delay = DEFAULT_PRESENTATION_DELAY;
g_mutex_init (&demux->client_lock);
gst_adaptive_demux_set_stream_struct_size (GST_ADAPTIVE_DEMUX_CAST (demux),
sizeof (GstDashDemuxStream));
}
static void
gst_dash_demux_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
GstAdaptiveDemux *adaptivedemux = GST_ADAPTIVE_DEMUX_CAST (object);
GstDashDemux *demux = GST_DASH_DEMUX (object);
switch (prop_id) {
case PROP_MAX_BUFFERING_TIME:
demux->max_buffering_time = g_value_get_uint (value) * GST_SECOND;
break;
case PROP_BANDWIDTH_USAGE:
adaptivedemux->bitrate_limit = g_value_get_float (value);
break;
case PROP_MAX_BITRATE:
demux->max_bitrate = g_value_get_uint (value);
break;
case PROP_PRESENTATION_DELAY:
g_free (demux->default_presentation_delay);
demux->default_presentation_delay = g_value_dup_string (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_dash_demux_get_property (GObject * object, guint prop_id, GValue * value,
GParamSpec * pspec)
{
GstAdaptiveDemux *adaptivedemux = GST_ADAPTIVE_DEMUX_CAST (object);
GstDashDemux *demux = GST_DASH_DEMUX (object);
switch (prop_id) {
case PROP_MAX_BUFFERING_TIME:
g_value_set_uint (value, demux->max_buffering_time / GST_SECOND);
break;
case PROP_BANDWIDTH_USAGE:
g_value_set_float (value, adaptivedemux->bitrate_limit);
break;
case PROP_MAX_BITRATE:
g_value_set_uint (value, demux->max_bitrate);
break;
case PROP_PRESENTATION_DELAY:
if (demux->default_presentation_delay == NULL)
g_value_set_static_string (value, "");
else
g_value_set_string (value, demux->default_presentation_delay);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static gboolean
gst_dash_demux_setup_mpdparser_streams (GstDashDemux * demux,
GstMpdClient * client)
{
gboolean has_streams = FALSE;
GList *adapt_sets, *iter;
adapt_sets = gst_mpd_client_get_adaptation_sets (client);
for (iter = adapt_sets; iter; iter = g_list_next (iter)) {
GstAdaptationSetNode *adapt_set_node = iter->data;
gst_mpd_client_setup_streaming (client, adapt_set_node);
has_streams = TRUE;
}
if (!has_streams) {
GST_ELEMENT_ERROR (demux, STREAM, DEMUX, ("Manifest has no playable "
"streams"), ("No streams could be activated from the manifest"));
}
return has_streams;
}
static gboolean
gst_dash_demux_setup_all_streams (GstDashDemux * demux)
{
guint i;
GST_DEBUG_OBJECT (demux, "Setting up streams for period %d",
gst_mpd_client_get_period_index (demux->client));
/* clean old active stream list, if any */
gst_active_streams_free (demux->client);
if (!gst_dash_demux_setup_mpdparser_streams (demux, demux->client)) {
return FALSE;
}
GST_DEBUG_OBJECT (demux, "Creating stream objects");
for (i = 0; i < gst_mpdparser_get_nb_active_stream (demux->client); i++) {
GstDashDemuxStream *stream;
GstActiveStream *active_stream;
GstCaps *caps;
GstPad *srcpad;
gchar *lang = NULL;
GstTagList *tags = NULL;
active_stream = gst_mpdparser_get_active_stream_by_index (demux->client, i);
if (active_stream == NULL)
continue;
srcpad = gst_dash_demux_create_pad (demux, active_stream);
if (srcpad == NULL)
continue;
caps = gst_dash_demux_get_input_caps (demux, active_stream);
GST_LOG_OBJECT (demux, "Creating stream %d %" GST_PTR_FORMAT, i, caps);
if (active_stream->cur_adapt_set) {
GstAdaptationSetNode *adp_set = active_stream->cur_adapt_set;
lang = adp_set->lang;
/* Fallback to the language in ContentComponent node */
if (lang == NULL) {
GList *it;
for (it = adp_set->ContentComponents; it; it = it->next) {
GstContentComponentNode *cc_node = it->data;
if (cc_node->lang) {
lang = cc_node->lang;
break;
}
}
}
}
if (lang) {
if (gst_tag_check_language_code (lang))
tags = gst_tag_list_new (GST_TAG_LANGUAGE_CODE, lang, NULL);
else
tags = gst_tag_list_new (GST_TAG_LANGUAGE_NAME, lang, NULL);
}
stream = (GstDashDemuxStream *)
gst_adaptive_demux_stream_new (GST_ADAPTIVE_DEMUX_CAST (demux), srcpad);
stream->active_stream = active_stream;
gst_adaptive_demux_stream_set_caps (GST_ADAPTIVE_DEMUX_STREAM_CAST (stream),
caps);
if (tags)
gst_adaptive_demux_stream_set_tags (GST_ADAPTIVE_DEMUX_STREAM_CAST
(stream), tags);
stream->index = i;
stream->pending_seek_ts = GST_CLOCK_TIME_NONE;
if (active_stream->cur_adapt_set &&
active_stream->cur_adapt_set->RepresentationBase &&
active_stream->cur_adapt_set->RepresentationBase->ContentProtection) {
GST_DEBUG_OBJECT (demux, "Adding ContentProtection events to source pad");
g_list_foreach (active_stream->cur_adapt_set->RepresentationBase->
ContentProtection, gst_dash_demux_send_content_protection_event,
stream);
}
gst_isoff_sidx_parser_init (&stream->sidx_parser);
}
return TRUE;
}
static void
gst_dash_demux_send_content_protection_event (gpointer data, gpointer userdata)
{
GstDescriptorType *cp = (GstDescriptorType *) data;
GstDashDemuxStream *stream = (GstDashDemuxStream *) userdata;
GstEvent *event;
GstBuffer *pssi;
glong pssi_len;
gchar *schemeIdUri;
if (cp->schemeIdUri == NULL)
return;
GST_TRACE_OBJECT (stream, "check schemeIdUri %s", cp->schemeIdUri);
/* RFC 2141 states: The leading "urn:" sequence is case-insensitive */
schemeIdUri = g_ascii_strdown (cp->schemeIdUri, -1);
if (g_str_has_prefix (schemeIdUri, "urn:uuid:")) {
pssi_len = strlen (cp->value);
pssi = gst_buffer_new_wrapped (g_memdup (cp->value, pssi_len), pssi_len);
GST_LOG_OBJECT (stream, "Queuing Protection event on source pad");
/* RFC 4122 states that the hex part of a UUID is in lower case,
* but some streams seem to ignore this and use upper case for the
* protection system ID */
event = gst_event_new_protection (cp->schemeIdUri + 9, pssi, "dash/mpd");
gst_adaptive_demux_stream_queue_event ((GstAdaptiveDemuxStream *) stream,
event);
gst_buffer_unref (pssi);
}
g_free (schemeIdUri);
}
static GstClockTime
gst_dash_demux_get_duration (GstAdaptiveDemux * ademux)
{
GstDashDemux *demux = GST_DASH_DEMUX_CAST (ademux);
g_return_val_if_fail (demux->client != NULL, GST_CLOCK_TIME_NONE);
return gst_mpd_client_get_media_presentation_duration (demux->client);
}
static gboolean
gst_dash_demux_is_live (GstAdaptiveDemux * ademux)
{
GstDashDemux *demux = GST_DASH_DEMUX_CAST (ademux);
g_return_val_if_fail (demux->client != NULL, FALSE);
return gst_mpd_client_is_live (demux->client);
}
static gboolean
gst_dash_demux_setup_streams (GstAdaptiveDemux * demux)
{
GstDashDemux *dashdemux = GST_DASH_DEMUX_CAST (demux);
gboolean ret = TRUE;
GstDateTime *now = NULL;
guint period_idx;
/* setup video, audio and subtitle streams, starting from first Period if
* non-live */
period_idx = 0;
if (gst_mpd_client_is_live (dashdemux->client)) {
GDateTime *g_now;
if (dashdemux->client->mpd_node->availabilityStartTime == NULL) {
ret = FALSE;
GST_ERROR_OBJECT (demux, "MPD does not have availabilityStartTime");
goto done;
}
if (dashdemux->clock_drift == NULL) {
gchar **urls;
urls =
gst_mpd_client_get_utc_timing_sources (dashdemux->client,
SUPPORTED_CLOCK_FORMATS, NULL);
if (urls) {
GST_DEBUG_OBJECT (dashdemux, "Found a supported UTCTiming element");
dashdemux->clock_drift = gst_dash_demux_clock_drift_new ();
gst_dash_demux_poll_clock_drift (dashdemux);
}
}
/* get period index for period encompassing the current time */
g_now = gst_dash_demux_get_server_now_utc (dashdemux);
now = gst_date_time_new_from_g_date_time (g_now);
if (dashdemux->client->mpd_node->suggestedPresentationDelay != -1) {
GstDateTime *target = gst_mpd_client_add_time_difference (now,
dashdemux->client->mpd_node->suggestedPresentationDelay * -1000);
gst_date_time_unref (now);
now = target;
} else if (dashdemux->default_presentation_delay) {
gint64 dfp =
gst_mpd_client_parse_default_presentation_delay (dashdemux->client,
dashdemux->default_presentation_delay);
GstDateTime *target = gst_mpd_client_add_time_difference (now, dfp);
gst_date_time_unref (now);
now = target;
}
period_idx =
gst_mpd_client_get_period_index_at_time (dashdemux->client, now);
if (period_idx == G_MAXUINT) {
#ifndef GST_DISABLE_GST_DEBUG
gchar *date_str = gst_date_time_to_iso8601_string (now);
GST_DEBUG_OBJECT (demux, "Unable to find live period active at %s",
date_str);
g_free (date_str);
#endif
ret = FALSE;
goto done;
}
}
if (!gst_mpd_client_set_period_index (dashdemux->client, period_idx) ||
!gst_dash_demux_setup_all_streams (dashdemux)) {
ret = FALSE;
goto done;
}
/* If stream is live, try to find the segment that
* is closest to current time */
if (gst_mpd_client_is_live (dashdemux->client)) {
GDateTime *gnow;
GST_DEBUG_OBJECT (demux, "Seeking to current time of day for live stream ");
gnow = gst_date_time_to_g_date_time (now);
gst_mpd_client_seek_to_time (dashdemux->client, gnow);
g_date_time_unref (gnow);
} else {
GST_DEBUG_OBJECT (demux, "Seeking to first segment for on-demand stream ");
/* start playing from the first segment */
gst_mpd_client_seek_to_first_segment (dashdemux->client);
}
done:
if (now != NULL)
gst_date_time_unref (now);
return ret;
}
static gboolean
gst_dash_demux_process_manifest (GstAdaptiveDemux * demux, GstBuffer * buf)
{
GstDashDemux *dashdemux = GST_DASH_DEMUX_CAST (demux);
gboolean ret = FALSE;
gchar *manifest;
GstMapInfo mapinfo;
if (dashdemux->client)
gst_mpd_client_free (dashdemux->client);
dashdemux->client = gst_mpd_client_new ();
gst_mpd_client_set_uri_downloader (dashdemux->client, demux->downloader);
dashdemux->client->mpd_uri = g_strdup (demux->manifest_uri);
dashdemux->client->mpd_base_uri = g_strdup (demux->manifest_base_uri);
GST_DEBUG_OBJECT (demux, "Fetched MPD file at URI: %s (base: %s)",
dashdemux->client->mpd_uri,
GST_STR_NULL (dashdemux->client->mpd_base_uri));
if (gst_buffer_map (buf, &mapinfo, GST_MAP_READ)) {
manifest = (gchar *) mapinfo.data;
if (gst_mpd_parse (dashdemux->client, manifest, mapinfo.size)) {
if (gst_mpd_client_setup_media_presentation (dashdemux->client, 0, 0,
NULL)) {
ret = TRUE;
} else {
GST_ELEMENT_ERROR (demux, STREAM, DECODE,
("Incompatible manifest file."), (NULL));
}
}
gst_buffer_unmap (buf, &mapinfo);
} else {
GST_WARNING_OBJECT (demux, "Failed to map manifest buffer");
}
if (ret)
ret = gst_dash_demux_setup_streams (demux);
return ret;
}
static GstPad *
gst_dash_demux_create_pad (GstDashDemux * demux, GstActiveStream * stream)
{
GstPad *pad;
GstPadTemplate *tmpl;
gchar *name;
switch (stream->mimeType) {
case GST_STREAM_AUDIO:
name = g_strdup_printf ("audio_%02u", demux->n_audio_streams++);
tmpl = gst_static_pad_template_get (&gst_dash_demux_audiosrc_template);
break;
case GST_STREAM_VIDEO:
name = g_strdup_printf ("video_%02u", demux->n_video_streams++);
tmpl = gst_static_pad_template_get (&gst_dash_demux_videosrc_template);
break;
case GST_STREAM_APPLICATION:
if (gst_mpd_client_active_stream_contains_subtitles (stream)) {
name = g_strdup_printf ("subtitle_%02u", demux->n_subtitle_streams++);
tmpl =
gst_static_pad_template_get (&gst_dash_demux_subtitlesrc_template);
} else {
return NULL;
}
break;
default:
g_assert_not_reached ();
return NULL;
}
/* Create and activate new pads */
pad = gst_pad_new_from_template (tmpl, name);
g_free (name);
gst_object_unref (tmpl);
gst_pad_set_active (pad, TRUE);
GST_INFO_OBJECT (demux, "Creating srcpad %s:%s", GST_DEBUG_PAD_NAME (pad));
return pad;
}
static void
gst_dash_demux_reset (GstAdaptiveDemux * ademux)
{
GstDashDemux *demux = GST_DASH_DEMUX_CAST (ademux);
GST_DEBUG_OBJECT (demux, "Resetting demux");
demux->end_of_period = FALSE;
demux->end_of_manifest = FALSE;
if (demux->client) {
gst_mpd_client_free (demux->client);
demux->client = NULL;
}
gst_dash_demux_clock_drift_free (demux->clock_drift);
demux->clock_drift = NULL;
demux->client = gst_mpd_client_new ();
gst_mpd_client_set_uri_downloader (demux->client, ademux->downloader);
demux->n_audio_streams = 0;
demux->n_video_streams = 0;
}
static GstCaps *
gst_dash_demux_get_video_input_caps (GstDashDemux * demux,
GstActiveStream * stream)
{
guint width = 0, height = 0;
gint fps_num = 0, fps_den = 1;
gboolean have_fps = FALSE;
GstCaps *caps = NULL;
if (stream == NULL)
return NULL;
/* if bitstreamSwitching is true we dont need to swich pads on resolution change */
if (!gst_mpd_client_get_bitstream_switching_flag (stream)) {
width = gst_mpd_client_get_video_stream_width (stream);
height = gst_mpd_client_get_video_stream_height (stream);
have_fps =
gst_mpd_client_get_video_stream_framerate (stream, &fps_num, &fps_den);
}
caps = gst_mpd_client_get_stream_caps (stream);
if (caps == NULL)
return NULL;
if (width > 0 && height > 0) {
gst_caps_set_simple (caps, "width", G_TYPE_INT, width, "height",
G_TYPE_INT, height, NULL);
}
if (have_fps) {
gst_caps_set_simple (caps, "framerate", GST_TYPE_FRACTION, fps_num,
fps_den, NULL);
}
return caps;
}
static GstCaps *
gst_dash_demux_get_audio_input_caps (GstDashDemux * demux,
GstActiveStream * stream)
{
guint rate = 0, channels = 0;
GstCaps *caps = NULL;
if (stream == NULL)
return NULL;
/* if bitstreamSwitching is true we dont need to swich pads on rate/channels change */
if (!gst_mpd_client_get_bitstream_switching_flag (stream)) {
channels = gst_mpd_client_get_audio_stream_num_channels (stream);
rate = gst_mpd_client_get_audio_stream_rate (stream);
}
caps = gst_mpd_client_get_stream_caps (stream);
if (caps == NULL)
return NULL;
if (rate > 0) {
gst_caps_set_simple (caps, "rate", G_TYPE_INT, rate, NULL);
}
if (channels > 0) {
gst_caps_set_simple (caps, "channels", G_TYPE_INT, channels, NULL);
}
return caps;
}
static GstCaps *
gst_dash_demux_get_application_input_caps (GstDashDemux * demux,
GstActiveStream * stream)
{
GstCaps *caps = NULL;
if (stream == NULL)
return NULL;
caps = gst_mpd_client_get_stream_caps (stream);
if (caps == NULL)
return NULL;
return caps;
}
static GstCaps *
gst_dash_demux_get_input_caps (GstDashDemux * demux, GstActiveStream * stream)
{
switch (stream->mimeType) {
case GST_STREAM_VIDEO:
return gst_dash_demux_get_video_input_caps (demux, stream);
case GST_STREAM_AUDIO:
return gst_dash_demux_get_audio_input_caps (demux, stream);
case GST_STREAM_APPLICATION:
return gst_dash_demux_get_application_input_caps (demux, stream);
default:
return GST_CAPS_NONE;
}
}
static void
gst_dash_demux_stream_update_headers_info (GstAdaptiveDemuxStream * stream)
{
GstDashDemuxStream *dashstream = (GstDashDemuxStream *) stream;
GstDashDemux *dashdemux = GST_DASH_DEMUX_CAST (stream->demux);
gchar *path = NULL;
gst_mpd_client_get_next_header (dashdemux->client,
&path, dashstream->index,
&stream->fragment.header_range_start, &stream->fragment.header_range_end);
if (path != NULL) {
stream->fragment.header_uri =
gst_uri_join_strings (gst_mpdparser_get_baseURL (dashdemux->client,
dashstream->index), path);
g_free (path);
path = NULL;
}
gst_mpd_client_get_next_header_index (dashdemux->client,
&path, dashstream->index,
&stream->fragment.index_range_start, &stream->fragment.index_range_end);
if (path != NULL) {
stream->fragment.index_uri =
gst_uri_join_strings (gst_mpdparser_get_baseURL (dashdemux->client,
dashstream->index), path);
g_free (path);
}
}
static GstFlowReturn
gst_dash_demux_stream_update_fragment_info (GstAdaptiveDemuxStream * stream)
{
GstDashDemuxStream *dashstream = (GstDashDemuxStream *) stream;
GstDashDemux *dashdemux = GST_DASH_DEMUX_CAST (stream->demux);
GstClockTime ts;
GstMediaFragmentInfo fragment;
gboolean isombff;
gst_adaptive_demux_stream_fragment_clear (&stream->fragment);
isombff = gst_mpd_client_has_isoff_ondemand_profile (dashdemux->client);
if (GST_ADAPTIVE_DEMUX_STREAM_NEED_HEADER (stream) && isombff) {
gst_dash_demux_stream_update_headers_info (stream);
dashstream->sidx_base_offset = stream->fragment.index_range_end + 1;
if (dashstream->sidx_index != 0) {
/* request only the index to be downloaded as we need to reposition the
* stream to a subsegment */
return GST_FLOW_OK;
}
}
if (gst_mpd_client_get_next_fragment_timestamp (dashdemux->client,
dashstream->index, &ts)) {
if (GST_ADAPTIVE_DEMUX_STREAM_NEED_HEADER (stream)) {
gst_adaptive_demux_stream_fragment_clear (&stream->fragment);
gst_dash_demux_stream_update_headers_info (stream);
}
gst_mpd_client_get_next_fragment (dashdemux->client, dashstream->index,
&fragment);
stream->fragment.uri = fragment.uri;
if (isombff && dashstream->sidx_index != 0) {
GstSidxBoxEntry *entry = SIDX_CURRENT_ENTRY (dashstream);
stream->fragment.range_start =
dashstream->sidx_base_offset + entry->offset;
stream->fragment.timestamp = entry->pts;
stream->fragment.duration = entry->duration;
if (stream->demux->segment.rate < 0.0) {
stream->fragment.range_end =
stream->fragment.range_start + entry->size - 1;
} else {
stream->fragment.range_end = fragment.range_end;
}
} else {
stream->fragment.timestamp = fragment.timestamp;
stream->fragment.duration = fragment.duration;
stream->fragment.range_start =
MAX (fragment.range_start, dashstream->sidx_base_offset);
stream->fragment.range_end = fragment.range_end;
}
return GST_FLOW_OK;
}
return GST_FLOW_EOS;
}
static gint
gst_dash_demux_index_entry_search (GstSidxBoxEntry * entry, GstClockTime * ts,
gpointer user_data)
{
GstClockTime entry_ts = entry->pts + entry->duration;
if (entry_ts < *ts)
return -1;
else if (entry->pts > *ts)
return 1;
else
return 0;
}
static void
gst_dash_demux_stream_sidx_seek (GstDashDemuxStream * dashstream,
gboolean forward, GstSeekFlags flags, GstClockTime ts,
GstClockTime * final_ts)
{
GstSidxBox *sidx = SIDX (dashstream);
GstSidxBoxEntry *entry;
gint idx = sidx->entries_count;
/* check whether ts is already past the last element or not */
if (sidx->entries[idx - 1].pts + sidx->entries[idx - 1].duration < ts) {
dashstream->sidx_current_remaining = 0;
} else {
GstSearchMode mode = GST_SEARCH_MODE_BEFORE;
if ((flags & GST_SEEK_FLAG_SNAP_NEAREST) == GST_SEEK_FLAG_SNAP_NEAREST) {
mode = GST_SEARCH_MODE_BEFORE;
} else if ((forward && (flags & GST_SEEK_FLAG_SNAP_AFTER)) ||
(!forward && (flags & GST_SEEK_FLAG_SNAP_BEFORE))) {
mode = GST_SEARCH_MODE_AFTER;
} else {
mode = GST_SEARCH_MODE_BEFORE;
}
entry =
gst_util_array_binary_search (sidx->entries, sidx->entries_count,
sizeof (GstSidxBoxEntry),
(GCompareDataFunc) gst_dash_demux_index_entry_search, mode, &ts, NULL);
idx = entry - sidx->entries;
/* FIXME in reverse mode, if we are exactly at a fragment start it makes more
* sense to start from the end of the previous fragment */
/* FIXME we should have a GST_SEARCH_MODE_NEAREST */
if ((flags & GST_SEEK_FLAG_SNAP_NEAREST) == GST_SEEK_FLAG_SNAP_NEAREST &&
idx + 1 < sidx->entries_count) {
if (ABS (sidx->entries[idx + 1].pts - ts) <
ABS (sidx->entries[idx].pts - ts))
idx += 1;
}
dashstream->sidx_current_remaining = sidx->entries[idx].size;
}
sidx->entry_index = idx;
dashstream->sidx_index = idx;
if (final_ts) {
if (idx == sidx->entries_count)
*final_ts = sidx->entries[idx].pts + sidx->entries[idx].duration;
else
*final_ts = sidx->entries[idx].pts;
}
}
static GstFlowReturn
gst_dash_demux_stream_seek (GstAdaptiveDemuxStream * stream, gboolean forward,
GstSeekFlags flags, GstClockTime ts, GstClockTime * final_ts)
{
GstDashDemuxStream *dashstream = (GstDashDemuxStream *) stream;
GstDashDemux *dashdemux = GST_DASH_DEMUX_CAST (stream->demux);
if (gst_mpd_client_has_isoff_ondemand_profile (dashdemux->client)) {
if (dashstream->sidx_parser.status == GST_ISOFF_SIDX_PARSER_FINISHED) {
gst_dash_demux_stream_sidx_seek (dashstream, forward, flags, ts,
final_ts);
} else {
/* no index yet, seek when we have it */
/* FIXME - the final_ts won't be correct here */
dashstream->pending_seek_ts = ts;
}
}
gst_mpd_client_stream_seek (dashdemux->client, dashstream->active_stream,
forward, flags, ts, final_ts);
return GST_FLOW_OK;
}
static gboolean
gst_dash_demux_stream_has_next_subfragment (GstAdaptiveDemuxStream * stream)
{
GstDashDemuxStream *dashstream = (GstDashDemuxStream *) stream;
GstSidxBox *sidx = SIDX (dashstream);
if (dashstream->sidx_parser.status == GST_ISOFF_SIDX_PARSER_FINISHED) {
if (stream->demux->segment.rate > 0.0) {
if (sidx->entry_index + 1 < sidx->entries_count)
return TRUE;
} else {
if (sidx->entry_index >= 1)
return TRUE;
}
}
return FALSE;
}
static gboolean
gst_dash_demux_stream_advance_subfragment (GstAdaptiveDemuxStream * stream)
{
GstDashDemuxStream *dashstream = (GstDashDemuxStream *) stream;
GstSidxBox *sidx = SIDX (dashstream);
gboolean fragment_finished = TRUE;
if (dashstream->sidx_parser.status == GST_ISOFF_SIDX_PARSER_FINISHED) {
if (stream->demux->segment.rate > 0.0) {
sidx->entry_index++;
if (sidx->entry_index < sidx->entries_count) {
fragment_finished = FALSE;
}
} else {
sidx->entry_index--;
if (sidx->entry_index >= 0) {
fragment_finished = FALSE;
}
}
}
GST_DEBUG_OBJECT (stream->pad, "New sidx index: %d / %d. "
"Finished fragment: %d", sidx->entry_index, sidx->entries_count,
fragment_finished);
if (!fragment_finished) {
dashstream->sidx_current_remaining = sidx->entries[sidx->entry_index].size;
}
return !fragment_finished;
}
static gboolean
gst_dash_demux_stream_has_next_fragment (GstAdaptiveDemuxStream * stream)
{
GstDashDemux *dashdemux = GST_DASH_DEMUX_CAST (stream->demux);
GstDashDemuxStream *dashstream = (GstDashDemuxStream *) stream;
if (gst_mpd_client_has_isoff_ondemand_profile (dashdemux->client)) {
if (gst_dash_demux_stream_has_next_subfragment (stream))
return TRUE;
}
return gst_mpd_client_has_next_segment (dashdemux->client,
dashstream->active_stream, stream->demux->segment.rate > 0.0);
}
static GstFlowReturn
gst_dash_demux_stream_advance_fragment (GstAdaptiveDemuxStream * stream)
{
GstDashDemuxStream *dashstream = (GstDashDemuxStream *) stream;
GstDashDemux *dashdemux = GST_DASH_DEMUX_CAST (stream->demux);
GST_DEBUG_OBJECT (stream->pad, "Advance fragment");
if (gst_mpd_client_has_isoff_ondemand_profile (dashdemux->client)) {
if (gst_dash_demux_stream_advance_subfragment (stream))
return GST_FLOW_OK;
}
return gst_mpd_client_advance_segment (dashdemux->client,
dashstream->active_stream, stream->demux->segment.rate > 0.0);
}
static gboolean
gst_dash_demux_stream_select_bitrate (GstAdaptiveDemuxStream * stream,
guint64 bitrate)
{
GstActiveStream *active_stream = NULL;
GList *rep_list = NULL;
gint new_index;
GstDashDemux *demux = GST_DASH_DEMUX_CAST (stream->demux);
GstDashDemuxStream *dashstream = (GstDashDemuxStream *) stream;
gboolean ret = FALSE;
active_stream = dashstream->active_stream;
if (active_stream == NULL) {
goto end;
}
/* retrieve representation list */
if (active_stream->cur_adapt_set)
rep_list = active_stream->cur_adapt_set->Representations;
if (!rep_list) {
goto end;
}
GST_DEBUG_OBJECT (stream->pad,
"Trying to change to bitrate: %" G_GUINT64_FORMAT, bitrate);
/* get representation index with current max_bandwidth */
new_index = gst_mpdparser_get_rep_idx_with_max_bandwidth (rep_list, bitrate);
/* if no representation has the required bandwidth, take the lowest one */
if (new_index == -1)
new_index = gst_mpdparser_get_rep_idx_with_min_bandwidth (rep_list);
if (new_index != active_stream->representation_idx) {
GstRepresentationNode *rep = g_list_nth_data (rep_list, new_index);
GST_INFO_OBJECT (demux, "Changing representation idx: %d %d %u",
dashstream->index, new_index, rep->bandwidth);
if (gst_mpd_client_setup_representation (demux->client, active_stream, rep)) {
GstCaps *caps;
GST_INFO_OBJECT (demux, "Switching bitrate to %d",
active_stream->cur_representation->bandwidth);
caps = gst_dash_demux_get_input_caps (demux, active_stream);
gst_adaptive_demux_stream_set_caps (stream, caps);
ret = TRUE;
} else {
GST_WARNING_OBJECT (demux, "Can not switch representation, aborting...");
}
}
if (gst_mpd_client_has_isoff_ondemand_profile (demux->client)) {
/* store our current position to change to the same one in a different
* representation if needed */
dashstream->sidx_index = SIDX (dashstream)->entry_index;
if (ret) {
/* TODO cache indexes to avoid re-downloading and parsing */
/* if we switched, we need a new index */
gst_isoff_sidx_parser_clear (&dashstream->sidx_parser);
gst_isoff_sidx_parser_init (&dashstream->sidx_parser);
}
}
end:
return ret;
}
#define SEEK_UPDATES_PLAY_POSITION(r, start_type, stop_type) \
((r >= 0 && start_type != GST_SEEK_TYPE_NONE) || \
(r < 0 && stop_type != GST_SEEK_TYPE_NONE))
static gboolean
gst_dash_demux_seek (GstAdaptiveDemux * demux, GstEvent * seek)
{
gdouble rate;
GstFormat format;
GstSeekFlags flags;
GstSeekType start_type, stop_type;
gint64 start, stop;
GList *list;
GstClockTime current_pos, target_pos;
guint current_period;
GstStreamPeriod *period;
GList *iter;
GstDashDemux *dashdemux = GST_DASH_DEMUX_CAST (demux);
gboolean switched_period = FALSE;
gst_event_parse_seek (seek, &rate, &format, &flags, &start_type, &start,
&stop_type, &stop);
if (!SEEK_UPDATES_PLAY_POSITION (rate, start_type, stop_type)) {
/* nothing to do if we don't have to update the current position */
return TRUE;
}
if (demux->segment.rate > 0.0) {
target_pos = (GstClockTime) start;
} else {
target_pos = (GstClockTime) stop;
}
/* select the requested Period in the Media Presentation */
if (!gst_mpd_client_setup_media_presentation (dashdemux->client, target_pos,
-1, NULL))
return FALSE;
current_period = 0;
for (list = g_list_first (dashdemux->client->periods); list;
list = g_list_next (list)) {
period = list->data;
current_pos = period->start;
current_period = period->number;
GST_DEBUG_OBJECT (demux, "Looking at period %u) start:%"
GST_TIME_FORMAT " - duration:%"
GST_TIME_FORMAT ") for position %" GST_TIME_FORMAT,
current_period, GST_TIME_ARGS (current_pos),
GST_TIME_ARGS (period->duration), GST_TIME_ARGS (target_pos));
if (current_pos <= target_pos
&& target_pos <= current_pos + period->duration) {
break;
}
}
if (list == NULL) {
GST_WARNING_OBJECT (demux, "Could not find seeked Period");
return FALSE;
}
if (current_period != gst_mpd_client_get_period_index (dashdemux->client)) {
GST_DEBUG_OBJECT (demux, "Seeking to Period %d", current_period);
/* clean old active stream list, if any */
gst_active_streams_free (dashdemux->client);
/* setup video, audio and subtitle streams, starting from the new Period */
if (!gst_mpd_client_set_period_index (dashdemux->client, current_period)
|| !gst_dash_demux_setup_all_streams (dashdemux))
return FALSE;
switched_period = TRUE;
}
/* Update the current sequence on all streams */
for (iter = (switched_period ? demux->next_streams : demux->streams); iter;
iter = g_list_next (iter)) {
GstDashDemuxStream *dashstream = iter->data;
if (flags & GST_SEEK_FLAG_FLUSH) {
gst_isoff_sidx_parser_clear (&dashstream->sidx_parser);
gst_isoff_sidx_parser_init (&dashstream->sidx_parser);
}
gst_dash_demux_stream_seek (iter->data, rate >= 0, 0, target_pos, NULL);
}
return TRUE;
}
static gint64
gst_dash_demux_get_manifest_update_interval (GstAdaptiveDemux * demux)
{
GstDashDemux *dashdemux = GST_DASH_DEMUX_CAST (demux);
return MIN (dashdemux->client->mpd_node->minimumUpdatePeriod * 1000,
SLOW_CLOCK_UPDATE_INTERVAL);
}
static GstFlowReturn
gst_dash_demux_update_manifest_data (GstAdaptiveDemux * demux,
GstBuffer * buffer)
{
GstDashDemux *dashdemux = GST_DASH_DEMUX_CAST (demux);
GstMpdClient *new_client = NULL;
GstMapInfo mapinfo;
GST_DEBUG_OBJECT (demux, "Updating manifest file from URL");
/* parse the manifest file */
new_client = gst_mpd_client_new ();
gst_mpd_client_set_uri_downloader (new_client, demux->downloader);
new_client->mpd_uri = g_strdup (demux->manifest_uri);
new_client->mpd_base_uri = g_strdup (demux->manifest_base_uri);
gst_buffer_map (buffer, &mapinfo, GST_MAP_READ);
if (gst_mpd_parse (new_client, (gchar *) mapinfo.data, mapinfo.size)) {
const gchar *period_id;
guint period_idx;
GList *iter;
GList *streams_iter;
/* prepare the new manifest and try to transfer the stream position
* status from the old manifest client */
GST_DEBUG_OBJECT (demux, "Updating manifest");
period_id = gst_mpd_client_get_period_id (dashdemux->client);
period_idx = gst_mpd_client_get_period_index (dashdemux->client);
/* setup video, audio and subtitle streams, starting from current Period */
if (!gst_mpd_client_setup_media_presentation (new_client, -1,
(period_id ? -1 : period_idx), period_id)) {
/* TODO */
}
if (period_id) {
if (!gst_mpd_client_set_period_id (new_client, period_id)) {
GST_DEBUG_OBJECT (demux, "Error setting up the updated manifest file");
gst_mpd_client_free (new_client);
gst_buffer_unmap (buffer, &mapinfo);
return GST_FLOW_EOS;
}
} else {
if (!gst_mpd_client_set_period_index (new_client, period_idx)) {
GST_DEBUG_OBJECT (demux, "Error setting up the updated manifest file");
gst_mpd_client_free (new_client);
gst_buffer_unmap (buffer, &mapinfo);
return GST_FLOW_EOS;
}
}
if (!gst_dash_demux_setup_mpdparser_streams (dashdemux, new_client)) {
GST_ERROR_OBJECT (demux, "Failed to setup streams on manifest " "update");
gst_mpd_client_free (new_client);
gst_buffer_unmap (buffer, &mapinfo);
return GST_FLOW_ERROR;
}
/* update the streams to play from the next segment */
for (iter = demux->streams, streams_iter = new_client->active_streams;
iter && streams_iter;
iter = g_list_next (iter), streams_iter = g_list_next (streams_iter)) {
GstDashDemuxStream *demux_stream = iter->data;
GstActiveStream *new_stream = streams_iter->data;
GstClockTime ts;
if (!new_stream) {
GST_DEBUG_OBJECT (demux,
"Stream of index %d is missing from manifest update",
demux_stream->index);
gst_mpd_client_free (new_client);
gst_buffer_unmap (buffer, &mapinfo);
return GST_FLOW_EOS;
}
if (gst_mpd_client_get_next_fragment_timestamp (dashdemux->client,
demux_stream->index, &ts)
|| gst_mpd_client_get_last_fragment_timestamp_end (dashdemux->client,
demux_stream->index, &ts)) {
/* Due to rounding when doing the timescale conversions it might happen
* that the ts falls back to a previous segment, leading the same data
* to be downloaded twice. We try to work around this by always adding
* 10 microseconds to get back to the correct segment. The errors are
* usually on the order of nanoseconds so it should be enough.
*/
GST_DEBUG_OBJECT (GST_ADAPTIVE_DEMUX_STREAM_PAD (demux_stream),
"Current position: %" GST_TIME_FORMAT ", updating to %"
GST_TIME_FORMAT, GST_TIME_ARGS (ts),
GST_TIME_ARGS (ts + (10 * GST_USECOND)));
ts += 10 * GST_USECOND;
gst_mpd_client_stream_seek (new_client, new_stream,
demux->segment.rate >= 0, 0, ts, NULL);
}
demux_stream->active_stream = new_stream;
}
gst_mpd_client_free (dashdemux->client);
dashdemux->client = new_client;
GST_DEBUG_OBJECT (demux, "Manifest file successfully updated");
if (dashdemux->clock_drift) {
gst_dash_demux_poll_clock_drift (dashdemux);
}
} else {
/* In most cases, this will happen if we set a wrong url in the
* source element and we have received the 404 HTML response instead of
* the manifest */
GST_WARNING_OBJECT (demux, "Error parsing the manifest.");
gst_mpd_client_free (new_client);
gst_buffer_unmap (buffer, &mapinfo);
return GST_FLOW_ERROR;
}
gst_buffer_unmap (buffer, &mapinfo);
return GST_FLOW_OK;
}
static gint64
gst_dash_demux_stream_get_fragment_waiting_time (GstAdaptiveDemuxStream *
stream)
{
GstDashDemux *dashdemux = GST_DASH_DEMUX_CAST (stream->demux);
GstDashDemuxStream *dashstream = (GstDashDemuxStream *) stream;
GstDateTime *segmentAvailability;
GstActiveStream *active_stream = dashstream->active_stream;
segmentAvailability =
gst_mpd_client_get_next_segment_availability_start_time
(dashdemux->client, active_stream);
if (segmentAvailability) {
gint64 diff;
GstDateTime *cur_time;
cur_time = gst_date_time_new_now_utc ();
diff = gst_mpd_client_calculate_time_difference (cur_time,
segmentAvailability);
gst_date_time_unref (segmentAvailability);
gst_date_time_unref (cur_time);
/* subtract the server's clock drift, so that if the server's
time is behind our idea of UTC, we need to sleep for longer
before requesting a fragment */
return diff -
gst_dash_demux_get_clock_compensation (dashdemux) * GST_USECOND;
}
return 0;
}
static gboolean
gst_dash_demux_has_next_period (GstAdaptiveDemux * demux)
{
GstDashDemux *dashdemux = GST_DASH_DEMUX_CAST (demux);
if (demux->segment.rate >= 0)
return gst_mpd_client_has_next_period (dashdemux->client);
else
return gst_mpd_client_has_previous_period (dashdemux->client);
}
static void
gst_dash_demux_advance_period (GstAdaptiveDemux * demux)
{
GstDashDemux *dashdemux = GST_DASH_DEMUX_CAST (demux);
g_return_if_fail (gst_mpd_client_has_next_period (dashdemux->client));
if (demux->segment.rate >= 0) {
if (!gst_mpd_client_set_period_index (dashdemux->client,
gst_mpd_client_get_period_index (dashdemux->client) + 1)) {
/* TODO error */
return;
}
} else {
if (!gst_mpd_client_set_period_index (dashdemux->client,
gst_mpd_client_get_period_index (dashdemux->client) - 1)) {
/* TODO error */
return;
}
}
gst_dash_demux_setup_all_streams (dashdemux);
gst_mpd_client_seek_to_first_segment (dashdemux->client);
}
static GstBuffer *
_gst_buffer_split (GstBuffer * buffer, gint offset, gsize size)
{
GstBuffer *newbuf = gst_buffer_copy_region (buffer,
GST_BUFFER_COPY_FLAGS | GST_BUFFER_COPY_TIMESTAMPS | GST_BUFFER_COPY_META
| GST_BUFFER_COPY_MEMORY, offset, size == -1 ? size : size - offset);
gst_buffer_resize (buffer, 0, offset);
return newbuf;
}
static GstFlowReturn
gst_dash_demux_stream_fragment_finished (GstAdaptiveDemux * demux,
GstAdaptiveDemuxStream * stream)
{
GstDashDemux *dashdemux = GST_DASH_DEMUX_CAST (demux);
GstDashDemuxStream *dashstream = (GstDashDemuxStream *) stream;
if (gst_mpd_client_has_isoff_ondemand_profile (dashdemux->client) &&
dashstream->sidx_parser.status == GST_ISOFF_SIDX_PARSER_FINISHED) {
/* fragment is advanced on data_received when byte limits are reached */
if (gst_dash_demux_stream_has_next_fragment (stream))
return GST_FLOW_OK;
return GST_FLOW_EOS;
}
if (G_UNLIKELY (stream->downloading_header || stream->downloading_index))
return GST_FLOW_OK;
return gst_adaptive_demux_stream_advance_fragment (demux, stream,
stream->fragment.duration);
}
static GstFlowReturn
gst_dash_demux_data_received (GstAdaptiveDemux * demux,
GstAdaptiveDemuxStream * stream)
{
GstDashDemuxStream *dash_stream = (GstDashDemuxStream *) stream;
GstDashDemux *dashdemux = GST_DASH_DEMUX_CAST (demux);
GstFlowReturn ret = GST_FLOW_OK;
GstBuffer *buffer;
gsize available;
if (!gst_mpd_client_has_isoff_ondemand_profile (dashdemux->client))
return GST_ADAPTIVE_DEMUX_CLASS (parent_class)->data_received (demux,
stream);
if (stream->downloading_index) {
GstIsoffParserResult res;
guint consumed;
available = gst_adapter_available (stream->adapter);
buffer = gst_adapter_take_buffer (stream->adapter, available);
if (dash_stream->sidx_parser.status != GST_ISOFF_SIDX_PARSER_FINISHED) {
res =
gst_isoff_sidx_parser_add_buffer (&dash_stream->sidx_parser, buffer,
&consumed);
if (res == GST_ISOFF_PARSER_ERROR) {
} else if (res == GST_ISOFF_PARSER_UNEXPECTED) {
/* this is not a 'sidx' index, just skip it and continue playback */
} else {
/* when finished, prepare for real data streaming */
if (dash_stream->sidx_parser.status == GST_ISOFF_SIDX_PARSER_FINISHED) {
if (GST_CLOCK_TIME_IS_VALID (dash_stream->pending_seek_ts)) {
/* FIXME, preserve seek flags */
gst_dash_demux_stream_sidx_seek (dash_stream,
demux->segment.rate >= 0, 0, dash_stream->pending_seek_ts,
NULL);
dash_stream->pending_seek_ts = GST_CLOCK_TIME_NONE;
} else {
SIDX (dash_stream)->entry_index = dash_stream->sidx_index;
}
dash_stream->sidx_current_remaining =
SIDX_CURRENT_ENTRY (dash_stream)->size;
} else if (consumed < available) {
GstBuffer *pending;
/* we still need to keep some data around for the next parsing round
* so just push what was already processed by the parser */
pending = _gst_buffer_split (buffer, consumed, -1);
gst_adapter_push (stream->adapter, pending);
}
}
}
ret = gst_adaptive_demux_stream_push_buffer (stream, buffer);
} else if (dash_stream->sidx_parser.status == GST_ISOFF_SIDX_PARSER_FINISHED) {
while (ret == GST_FLOW_OK
&& ((available = gst_adapter_available (stream->adapter)) > 0)) {
gboolean advance = FALSE;
if (available < dash_stream->sidx_current_remaining) {
buffer = gst_adapter_take_buffer (stream->adapter, available);
dash_stream->sidx_current_remaining -= available;
} else {
buffer =
gst_adapter_take_buffer (stream->adapter,
dash_stream->sidx_current_remaining);
dash_stream->sidx_current_remaining = 0;
advance = TRUE;
}
ret = gst_adaptive_demux_stream_push_buffer (stream, buffer);
if (advance) {
GstFlowReturn new_ret;
new_ret =
gst_adaptive_demux_stream_advance_fragment (demux, stream,
SIDX_CURRENT_ENTRY (dash_stream)->duration);
/* only overwrite if it was OK before */
if (ret == GST_FLOW_OK)
ret = new_ret;
}
}
} else {
/* this should be the main header, just push it all */
ret =
gst_adaptive_demux_stream_push_buffer (stream,
gst_adapter_take_buffer (stream->adapter,
gst_adapter_available (stream->adapter)));
}
return ret;
}
static void
gst_dash_demux_stream_free (GstAdaptiveDemuxStream * stream)
{
GstDashDemuxStream *dash_stream = (GstDashDemuxStream *) stream;
gst_isoff_sidx_parser_clear (&dash_stream->sidx_parser);
}
static GstDashDemuxClockDrift *
gst_dash_demux_clock_drift_new (void)
{
GstDashDemuxClockDrift *clock_drift;
clock_drift = g_slice_new0 (GstDashDemuxClockDrift);
g_mutex_init (&clock_drift->clock_lock);
clock_drift->next_update = g_get_monotonic_time ();
return clock_drift;
}
static void
gst_dash_demux_clock_drift_free (GstDashDemuxClockDrift * clock_drift)
{
if (clock_drift) {
g_mutex_lock (&clock_drift->clock_lock);
if (clock_drift->ntp_clock)
g_object_unref (clock_drift->ntp_clock);
g_mutex_unlock (&clock_drift->clock_lock);
g_mutex_clear (&clock_drift->clock_lock);
g_slice_free (GstDashDemuxClockDrift, clock_drift);
}
}
/*
* The value attribute of the UTCTiming element contains a white-space
* separated list of servers that are recommended to be used in
* combination with the NTP protocol as defined in IETF RFC 5905 for
* getting the appropriate time.
*
* The DASH standard does not specify which version of NTP. This
* function only works with NTPv4 servers.
*/
static GstDateTime *
gst_dash_demux_poll_ntp_server (GstDashDemuxClockDrift * clock_drift,
gchar ** urls)
{
GstClockTime ntp_clock_time;
GDateTime *dt, *dt2;
if (!clock_drift->ntp_clock) {
GResolver *resolver;
GList *inet_addrs;
GError *err;
gchar *ip_addr;
resolver = g_resolver_get_default ();
/* We don't round-robin NTP servers. If the manifest specifies multiple
NTP time servers, select one at random */
clock_drift->selected_url = g_random_int_range (0, g_strv_length (urls));
GST_DEBUG ("Connecting to NTP time server %s",
urls[clock_drift->selected_url]);
inet_addrs = g_resolver_lookup_by_name (resolver,
urls[clock_drift->selected_url], NULL, &err);
g_object_unref (resolver);
if (!inet_addrs || g_list_length (inet_addrs) == 0) {
GST_ERROR ("Failed to resolve hostname of NTP server: %s",
err ? (err->message) : "unknown error");
if (inet_addrs)
g_resolver_free_addresses (inet_addrs);
if (err)
g_error_free (err);
return NULL;
}
ip_addr =
g_inet_address_to_string ((GInetAddress
*) (g_list_first (inet_addrs)->data));
clock_drift->ntp_clock = gst_ntp_clock_new ("dashntp", ip_addr, 123, 0);
g_free (ip_addr);
g_resolver_free_addresses (inet_addrs);
if (!clock_drift->ntp_clock) {
GST_ERROR ("Failed to create NTP clock");
return NULL;
}
if (!gst_clock_wait_for_sync (clock_drift->ntp_clock, 5 * GST_SECOND)) {
g_object_unref (clock_drift->ntp_clock);
clock_drift->ntp_clock = NULL;
GST_ERROR ("Failed to lock to NTP clock");
return NULL;
}
}
ntp_clock_time = gst_clock_get_time (clock_drift->ntp_clock);
if (ntp_clock_time == GST_CLOCK_TIME_NONE) {
GST_ERROR ("Failed to get time from NTP clock");
return NULL;
}
ntp_clock_time -= NTP_TO_UNIX_EPOCH * GST_SECOND;
dt = g_date_time_new_from_unix_utc (ntp_clock_time / GST_SECOND);
if (!dt) {
GST_ERROR ("Failed to create GstDateTime");
return NULL;
}
ntp_clock_time =
gst_util_uint64_scale (ntp_clock_time % GST_SECOND, 1000000, GST_SECOND);
dt2 = g_date_time_add (dt, ntp_clock_time);
g_date_time_unref (dt);
return gst_date_time_new_from_g_date_time (dt2);
}
struct Rfc5322TimeZone
{
const gchar *name;
gfloat tzoffset;
};
/*
Parse an RFC5322 (section 3.3) date-time from the Date: field in the
HTTP response.
See https://tools.ietf.org/html/rfc5322#section-3.3
*/
static GstDateTime *
gst_dash_demux_parse_http_head (GstDashDemuxClockDrift * clock_drift,
GstFragment * download)
{
static const gchar *months[] = { NULL, "Jan", "Feb", "Mar", "Apr",
"May", "Jun", "Jul", "Aug",
"Sep", "Oct", "Nov", "Dec", NULL
};
static const struct Rfc5322TimeZone timezones[] = {
{"Z", 0},
{"UT", 0},
{"GMT", 0},
{"BST", 1},
{"EST", -5},
{"EDT", -4},
{"CST", -6},
{"CDT", -5},
{"MST", -7},
{"MDT", -6},
{"PST", -8},
{"PDT", -7},
{NULL, 0}
};
GstDateTime *value = NULL;
const GstStructure *response_headers;
const gchar *http_date;
const GValue *val;
gint ret;
const gchar *pos;
gint year = -1, month = -1, day = -1, hour = -1, minute = -1, second = -1;
gchar zone[6];
gchar monthstr[4];
gfloat tzoffset = 0;
gboolean parsed_tz = FALSE;
g_return_val_if_fail (download != NULL, NULL);
g_return_val_if_fail (download->headers != NULL, NULL);
val = gst_structure_get_value (download->headers, "response-headers");
if (!val) {
return NULL;
}
response_headers = gst_value_get_structure (val);
http_date = gst_structure_get_string (response_headers, "Date");
if (!http_date) {
return NULL;
}
/* skip optional text version of day of the week */
pos = strchr (http_date, ',');
if (pos)
pos++;
else
pos = http_date;
ret =
sscanf (pos, "%02d %3s %04d %02d:%02d:%02d %5s", &day, monthstr, &year,
&hour, &minute, &second, zone);
if (ret == 7) {
gchar *z = zone;
for (int i = 1; months[i]; ++i) {
if (g_ascii_strncasecmp (months[i], monthstr, strlen (months[i])) == 0) {
month = i;
break;
}
}
for (int i = 0; timezones[i].name && !parsed_tz; ++i) {
if (g_ascii_strncasecmp (timezones[i].name, z,
strlen (timezones[i].name)) == 0) {
tzoffset = timezones[i].tzoffset;
parsed_tz = TRUE;
}
}
if (!parsed_tz) {
gint hh, mm;
gboolean neg = FALSE;
/* check if it is in the form +-HHMM */
if (*z == '+' || *z == '-') {
if (*z == '+')
++z;
else if (*z == '-') {
++z;
neg = TRUE;
}
ret = sscanf (z, "%02d%02d", &hh, &mm);
if (ret == 2) {
tzoffset = hh;
tzoffset += mm / 60.0;
if (neg)
tzoffset = -tzoffset;
parsed_tz = TRUE;
}
}
}
/* Accept year in both 2 digit or 4 digit format */
if (year < 100)
year += 2000;
}
if (month > 0 && parsed_tz) {
value = gst_date_time_new (tzoffset,
year, month, day, hour, minute, second);
}
return value;
}
/*
The timing information is contained in the message body of the HTTP
response and contains a time value formatted according to NTP timestamp
format in IETF RFC 5905.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Seconds |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Fraction |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
NTP Timestamp Format
*/
static GstDateTime *
gst_dash_demux_parse_http_ntp (GstDashDemuxClockDrift * clock_drift,
GstBuffer * buffer)
{
gint64 seconds;
guint64 fraction;
GDateTime *dt, *dt2;
GstMapInfo mapinfo;
/* See https://tools.ietf.org/html/rfc5905#page-12 for details of
the NTP Timestamp Format */
gst_buffer_map (buffer, &mapinfo, GST_MAP_READ);
if (mapinfo.size != 8) {
gst_buffer_unmap (buffer, &mapinfo);
return NULL;
}
seconds = GST_READ_UINT32_BE (mapinfo.data);
fraction = GST_READ_UINT32_BE (mapinfo.data + 4);
gst_buffer_unmap (buffer, &mapinfo);
fraction = gst_util_uint64_scale (fraction, 1000000,
G_GUINT64_CONSTANT (1) << 32);
/* subtract constant to convert from 1900 based time to 1970 based time */
seconds -= NTP_TO_UNIX_EPOCH;
dt = g_date_time_new_from_unix_utc (seconds);
dt2 = g_date_time_add (dt, fraction);
g_date_time_unref (dt);
return gst_date_time_new_from_g_date_time (dt2);
}
/*
The timing information is contained in the message body of the
HTTP response and contains a time value formatted according to
xs:dateTime as defined in W3C XML Schema Part 2: Datatypes specification.
*/
static GstDateTime *
gst_dash_demux_parse_http_xsdate (GstDashDemuxClockDrift * clock_drift,
GstBuffer * buffer)
{
GstDateTime *value;
GstMapInfo mapinfo;
/* the string from the server might not be zero terminated */
gst_buffer_resize (buffer, 0, gst_buffer_get_size (buffer) + 1);
gst_buffer_map (buffer, &mapinfo, GST_MAP_READ | GST_MAP_WRITE);
mapinfo.data[mapinfo.size - 1] = '\0';
value = gst_date_time_new_from_iso8601_string ((const gchar *) mapinfo.data);
gst_buffer_unmap (buffer, &mapinfo);
return value;
}
static gboolean
gst_dash_demux_poll_clock_drift (GstDashDemux * demux)
{
GstDashDemuxClockDrift *clock_drift;
GDateTime *start = NULL, *end;
GstBuffer *buffer = NULL;
GstDateTime *value = NULL;
gboolean ret = FALSE;
gint64 now;
GstMPDUTCTimingType method;
gchar **urls;
g_return_val_if_fail (demux != NULL, FALSE);
g_return_val_if_fail (demux->clock_drift != NULL, FALSE);
clock_drift = demux->clock_drift;
now = g_get_monotonic_time ();
if (now < clock_drift->next_update) {
/*TODO: If a fragment fails to download in adaptivedemux, it waits
for a manifest reload before another attempt to fetch a fragment.
Section 10.8.6 of the DVB-DASH standard states that the DASH client
shall refresh the manifest and resynchronise to one of the time sources.
Currently the fact that the manifest refresh follows a download failure
does not make it into dashdemux. */
return TRUE;
}
urls = gst_mpd_client_get_utc_timing_sources (demux->client,
SUPPORTED_CLOCK_FORMATS, &method);
if (!urls) {
return FALSE;
}
/* Update selected_url just in case the number of URLs in the UTCTiming
element has shrunk since the last poll */
clock_drift->selected_url = clock_drift->selected_url % g_strv_length (urls);
g_mutex_lock (&clock_drift->clock_lock);
if (method == GST_MPD_UTCTIMING_TYPE_NTP) {
value = gst_dash_demux_poll_ntp_server (clock_drift, urls);
if (!value) {
GST_ERROR_OBJECT (demux, "Failed to fetch time from NTP server %s",
urls[clock_drift->selected_url]);
g_mutex_unlock (&clock_drift->clock_lock);
goto quit;
}
}
start = g_date_time_new_now_utc ();
if (!value) {
GstFragment *download;
gint64 range_start = 0, range_end = -1;
GST_DEBUG_OBJECT (demux, "Fetching current time from %s",
urls[clock_drift->selected_url]);
if (method == GST_MPD_UTCTIMING_TYPE_HTTP_HEAD) {
range_start = -1;
}
download =
gst_uri_downloader_fetch_uri_with_range (GST_ADAPTIVE_DEMUX_CAST
(demux)->downloader, urls[clock_drift->selected_url], NULL, TRUE, TRUE,
TRUE, range_start, range_end, NULL);
if (download) {
if (method == GST_MPD_UTCTIMING_TYPE_HTTP_HEAD && download->headers) {
value = gst_dash_demux_parse_http_head (clock_drift, download);
} else {
buffer = gst_fragment_get_buffer (download);
}
g_object_unref (download);
}
}
g_mutex_unlock (&clock_drift->clock_lock);
if (!value && !buffer) {
GST_ERROR_OBJECT (demux, "Failed to fetch time from %s",
urls[clock_drift->selected_url]);
goto quit;
}
end = g_date_time_new_now_utc ();
if (!value && method == GST_MPD_UTCTIMING_TYPE_HTTP_NTP) {
value = gst_dash_demux_parse_http_ntp (clock_drift, buffer);
} else if (!value) {
/* GST_MPD_UTCTIMING_TYPE_HTTP_XSDATE or GST_MPD_UTCTIMING_TYPE_HTTP_ISO */
value = gst_dash_demux_parse_http_xsdate (clock_drift, buffer);
}
if (buffer)
gst_buffer_unref (buffer);
if (value) {
GTimeSpan download_duration = g_date_time_difference (end, start);
GDateTime *client_now, *server_now;
/* We don't know when the server sampled its clock, but we know
it must have been before "end" and probably after "start".
A reasonable estimate is to use (start+end)/2
*/
client_now = g_date_time_add (start, download_duration / 2);
server_now = gst_date_time_to_g_date_time (value);
/* If gst_date_time_new_from_iso8601_string is given an unsupported
ISO 8601 format, it can return a GstDateTime that is not valid,
which causes gst_date_time_to_g_date_time to return NULL */
if (server_now) {
g_mutex_lock (&clock_drift->clock_lock);
clock_drift->clock_compensation =
g_date_time_difference (server_now, client_now);
g_mutex_unlock (&clock_drift->clock_lock);
GST_DEBUG_OBJECT (demux,
"Difference between client and server clocks is %lfs",
((double) clock_drift->clock_compensation) / 1000000.0);
g_date_time_unref (server_now);
ret = TRUE;
} else {
GST_ERROR_OBJECT (demux, "Failed to parse DateTime from server");
}
g_date_time_unref (client_now);
gst_date_time_unref (value);
} else {
GST_ERROR_OBJECT (demux, "Failed to parse DateTime from server");
}
g_date_time_unref (end);
quit:
if (start)
g_date_time_unref (start);
/* if multiple URLs were specified, use a simple round-robin to
poll each server */
g_mutex_lock (&clock_drift->clock_lock);
if (method == GST_MPD_UTCTIMING_TYPE_NTP) {
clock_drift->next_update = now + FAST_CLOCK_UPDATE_INTERVAL;
} else {
clock_drift->selected_url =
(1 + clock_drift->selected_url) % g_strv_length (urls);
if (ret) {
clock_drift->next_update = now + SLOW_CLOCK_UPDATE_INTERVAL;
} else {
clock_drift->next_update = now + FAST_CLOCK_UPDATE_INTERVAL;
}
}
g_mutex_unlock (&clock_drift->clock_lock);
return ret;
}
static GTimeSpan
gst_dash_demux_get_clock_compensation (GstDashDemux * demux)
{
GTimeSpan rv = 0;
if (demux->clock_drift) {
g_mutex_lock (&demux->clock_drift->clock_lock);
rv = demux->clock_drift->clock_compensation;
g_mutex_unlock (&demux->clock_drift->clock_lock);
}
GST_LOG_OBJECT (demux, "Clock drift %" GST_STIME_FORMAT, GST_STIME_ARGS (rv));
return rv;
}
static GDateTime *
gst_dash_demux_get_server_now_utc (GstDashDemux * demux)
{
GDateTime *client_now = g_date_time_new_now_utc ();
GDateTime *server_now = g_date_time_add (client_now,
gst_dash_demux_get_clock_compensation (demux));
g_date_time_unref (client_now);
return server_now;
}
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