gstreamer/subprojects/gst-editing-services/ges/ges-source.c
Mathieu Duponchelle e728c0e71a ges-source: make sure internal decodebin doesn't get seeked too early
When uridecodebin exposes pads for its streams, we immediately ghost
the relevant (selected) one and let composition send a seek as soon as a
buffer is probed.

This means that sometimes uridecodebin is still linking elements
internally (for non-selected streams) and sees flush events travel down
the elements it is still busy trying to link / forward sticky events to.

This causes all sorts of nasty issues, which can be avoided by simply
blocking all data flow from the source until no-more-pads has been
emitted by uridecodebin (or whatever sub_element is wrapped).

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/3971>
2023-02-15 22:24:51 +00:00

303 lines
8.5 KiB
C

/* GStreamer Editing Services
* Copyright (C) 2009 Edward Hervey <edward.hervey@collabora.co.uk>
* 2009 Nokia Corporation
*
* 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., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
/**
* SECTION:gessource
* @title: GESSource
* @short_description: Base Class for single-media sources
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "ges-internal.h"
#include "ges/ges-meta-container.h"
#include "ges-track-element.h"
#include "ges-source.h"
#include "ges-layer.h"
#include "gstframepositioner.h"
struct _GESSourcePrivate
{
GstElement *topbin;
GstElement *first_converter;
GstElement *last_converter;
GstPad *ghostpad;
GList *sub_element_probes;
GMutex sub_element_lock;
gboolean is_rendering_smartly;
};
G_DEFINE_TYPE_WITH_PRIVATE (GESSource, ges_source, GES_TYPE_TRACK_ELEMENT);
/******************************
* Internal helper methods *
******************************/
static GstElement *
link_elements (GstElement * bin, GPtrArray * elements)
{
GstElement *element, *prev = NULL, *first = NULL;
gint i;
for (i = 0; i < elements->len; i++) {
element = elements->pdata[i];
if (!element)
continue;
gst_bin_add (GST_BIN (bin), element);
if (prev) {
if (!gst_element_link_pads_full (prev, "src", element, "sink",
GST_PAD_LINK_CHECK_NOTHING)) {
if (!gst_element_link (prev, element)) {
g_error ("Could not link %s and %s", GST_OBJECT_NAME (prev),
GST_OBJECT_NAME (element));
}
}
}
prev = element;
if (first == NULL)
first = element;
}
return prev;
}
typedef struct
{
GstPad *pad;
gulong probe_id;
} ProbeData;
static GstPadProbeReturn
pad_probe_cb (GstPad * pad, GstPadProbeInfo * info, gpointer user_data)
{
return GST_PAD_PROBE_OK;
}
static void
_release_probe_data (ProbeData * pdata)
{
gst_pad_remove_probe (pdata->pad, pdata->probe_id);
gst_object_unref (pdata->pad);
g_free (pdata);
}
static void
_no_more_pads_cb (GstElement * element, GESSource * self)
{
GESSourcePrivate *priv = self->priv;
GST_DEBUG_OBJECT (self,
"Unblocking after no more pads from sub_element %" GST_PTR_FORMAT,
element);
g_mutex_lock (&priv->sub_element_lock);
g_list_free_full (priv->sub_element_probes,
(GDestroyNotify) _release_probe_data);
priv->sub_element_probes = NULL;
g_mutex_unlock (&priv->sub_element_lock);
}
static void
_set_ghost_pad_target (GESSource * self, GstPad * srcpad, GstElement * element)
{
GstPadLinkReturn link_return;
GESSourcePrivate *priv = self->priv;
GESSourceClass *source_klass = GES_SOURCE_GET_CLASS (self);
gboolean use_converter = ! !priv->first_converter;
if (source_klass->select_pad && !source_klass->select_pad (self, srcpad)) {
GST_INFO_OBJECT (self, "Ignoring pad %" GST_PTR_FORMAT, srcpad);
return;
}
if (use_converter && priv->is_rendering_smartly) {
GstPad *pad = gst_element_get_static_pad (priv->first_converter, "sink");
use_converter = gst_pad_can_link (srcpad, pad);
gst_object_unref (pad);
}
if (use_converter) {
GstPad *converter_src, *sinkpad;
converter_src = gst_element_get_static_pad (priv->last_converter, "src");
if (!gst_ghost_pad_set_target (GST_GHOST_PAD (priv->ghostpad),
converter_src)) {
GST_ERROR_OBJECT (self, "Could not set ghost target");
}
sinkpad = gst_element_get_static_pad (priv->first_converter, "sink");
link_return = gst_pad_link (srcpad, sinkpad);
#ifndef GST_DISABLE_GST_DEBUG
if (link_return != GST_PAD_LINK_OK) {
GstCaps *srccaps = NULL;
GstCaps *sinkcaps = NULL;
srccaps = gst_pad_query_caps (srcpad, NULL);
sinkcaps = gst_pad_query_caps (sinkpad, NULL);
GST_ERROR_OBJECT (element, "Could not link source with "
"conversion bin: %s (srcpad caps %" GST_PTR_FORMAT
" sinkpad caps: %" GST_PTR_FORMAT ")",
gst_pad_link_get_name (link_return), srccaps, sinkcaps);
gst_caps_unref (srccaps);
gst_caps_unref (sinkcaps);
}
#endif
gst_object_unref (converter_src);
gst_object_unref (sinkpad);
} else {
if (!gst_ghost_pad_set_target (GST_GHOST_PAD (priv->ghostpad), srcpad))
GST_ERROR_OBJECT (self, "Could not set ghost target");
}
}
static void
_pad_added_cb (GstElement * element, GstPad * srcpad, GESSource * self)
{
GESSourcePrivate *priv = self->priv;
ProbeData *pdata = g_new0 (ProbeData, 1);
GST_LOG_OBJECT (self, "blocking sub_element srcpad %" GST_PTR_FORMAT, srcpad);
pdata->probe_id = gst_pad_add_probe (srcpad,
GST_PAD_PROBE_TYPE_BLOCK_DOWNSTREAM,
(GstPadProbeCallback) pad_probe_cb, NULL, NULL);
pdata->pad = gst_object_ref (srcpad);
g_mutex_lock (&priv->sub_element_lock);
priv->sub_element_probes = g_list_append (priv->sub_element_probes, pdata);
g_mutex_unlock (&priv->sub_element_lock);
_set_ghost_pad_target (self, srcpad, element);
}
/* @elements: (transfer-full) */
GstElement *
ges_source_create_topbin (GESSource * source, const gchar * bin_name,
GstElement * sub_element, GPtrArray * elements)
{
GstElement *last;
GstElement *bin;
GstPad *sub_srcpad;
GESSourcePrivate *priv = source->priv;
bin = gst_bin_new (bin_name);
if (!gst_bin_add (GST_BIN (bin), sub_element)) {
GST_ERROR_OBJECT (source, "Could not add sub element: %" GST_PTR_FORMAT,
sub_element);
gst_object_unref (bin);
return NULL;
}
priv->ghostpad = gst_object_ref (gst_ghost_pad_new_no_target ("src",
GST_PAD_SRC));
gst_pad_set_active (priv->ghostpad, TRUE);
gst_element_add_pad (bin, priv->ghostpad);
priv->topbin = gst_object_ref (bin);
last = link_elements (bin, elements);
if (last) {
gint i = 0;
while (!elements->pdata[i])
i++;
priv->first_converter = gst_object_ref (elements->pdata[i]);
priv->last_converter = gst_object_ref (last);
}
sub_srcpad = gst_element_get_static_pad (sub_element, "src");
if (sub_srcpad) {
_set_ghost_pad_target (source, sub_srcpad, sub_element);
gst_object_unref (sub_srcpad);
} else {
GST_INFO_OBJECT (source, "Waiting for pad added");
g_signal_connect (sub_element, "pad-added",
G_CALLBACK (_pad_added_cb), source);
g_signal_connect (sub_element, "no-more-pads",
G_CALLBACK (_no_more_pads_cb), source);
}
g_ptr_array_free (elements, TRUE);
return bin;
}
void
ges_source_set_rendering_smartly (GESSource * source,
gboolean is_rendering_smartly)
{
if (is_rendering_smartly) {
GESTrack *track = ges_track_element_get_track (GES_TRACK_ELEMENT (source));
if (track && ges_track_get_mixing (track)) {
GST_DEBUG_OBJECT (source, "Not rendering smartly as track is mixing!");
source->priv->is_rendering_smartly = FALSE;
return;
}
}
source->priv->is_rendering_smartly = is_rendering_smartly;
}
gboolean
ges_source_get_rendering_smartly (GESSource * source)
{
return source->priv->is_rendering_smartly;
}
static void
ges_source_dispose (GObject * object)
{
GESSourcePrivate *priv = GES_SOURCE (object)->priv;
gst_clear_object (&priv->first_converter);
gst_clear_object (&priv->last_converter);
gst_clear_object (&priv->topbin);
gst_clear_object (&priv->ghostpad);
g_list_free_full (priv->sub_element_probes,
(GDestroyNotify) _release_probe_data);
g_mutex_clear (&priv->sub_element_lock);
G_OBJECT_CLASS (ges_source_parent_class)->dispose (object);
}
static void
ges_source_class_init (GESSourceClass * klass)
{
GESTrackElementClass *track_class = GES_TRACK_ELEMENT_CLASS (klass);
GObjectClass *object_class = G_OBJECT_CLASS (klass);
track_class->nleobject_factorytype = "nlesource";
track_class->create_element = NULL;
object_class->dispose = ges_source_dispose;
GES_TRACK_ELEMENT_CLASS_DEFAULT_HAS_INTERNAL_SOURCE (klass) = TRUE;
}
static void
ges_source_init (GESSource * self)
{
self->priv = ges_source_get_instance_private (self);
g_mutex_init (&self->priv->sub_element_lock);
}