gstreamer/gst/playback/gstdecodebin.c
Wim Taymans 5d374bf5ea gst/playback/: Cleanups and some more documentation.
Original commit message from CVS:
* gst/playback/README:
* gst/playback/gstdecodebin.c: (close_pad_link), (try_to_link_1):
* gst/playback/gstplaybin.c: (gst_play_bin_init),
(gst_play_bin_dispose), (gst_play_bin_set_property),
(remove_sinks), (setup_sinks), (gst_play_bin_change_state),
(gst_play_bin_get_event_masks), (gst_play_bin_send_event),
(gst_play_bin_get_formats), (gst_play_bin_convert),
(gst_play_bin_get_query_types), (gst_play_bin_query):
Cleanups and some more documentation.
2004-11-09 14:37:51 +00:00

945 lines
30 KiB
C

/* GStreamer
* Copyright (C) <2004> Wim Taymans <wim@fluendo.com>
*
* 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 <gst/gst.h>
#include "gstplay-marshal.h"
/* generic templates */
static GstStaticPadTemplate decoder_bin_sink_template =
GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS_ANY);
static GstStaticPadTemplate decoder_bin_src_template =
GST_STATIC_PAD_TEMPLATE ("src%d",
GST_PAD_SRC,
GST_PAD_SOMETIMES,
GST_STATIC_CAPS_ANY);
GST_DEBUG_CATEGORY_STATIC (gst_decode_bin_debug);
#define GST_CAT_DEFAULT gst_decode_bin_debug
#define GST_TYPE_DECODE_BIN (gst_decode_bin_get_type())
#define GST_DECODE_BIN(obj) (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_DECODE_BIN,GstDecodeBin))
#define GST_DECODE_BIN_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_DECODE_BIN,GstDecodeBinClass))
#define GST_IS_DECODE_BIN(obj) (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_DECODE_BIN))
#define GST_IS_DECODE_BIN_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_DECODE_BIN))
typedef struct _GstDecodeBin GstDecodeBin;
typedef struct _GstDecodeBinClass GstDecodeBinClass;
struct _GstDecodeBin
{
GstBin bin; /* we extend GstBin */
GstElement *typefind; /* this holds the typefind object */
gboolean threaded; /* indicating threaded execution is desired */
GList *dynamics; /* list of dynamic connections */
GList *factories; /* factories we can use for selecting elements */
gint numpads;
GList *elements; /* elements we added in autoplugging */
guint have_type_id; /* signal id for the typefind element */
};
struct _GstDecodeBinClass
{
GstBinClass parent_class;
/* signal we fire when a new pad has been decoded into raw audio/video */
void (*new_decoded_pad) (GstElement * element, GstPad * pad, gboolean last);
/* signal we fire when a pad has been removed */
void (*removed_decoded_pad) (GstElement * element, GstPad * pad);
/* signal fired when we found a pad that we cannot decode */
void (*unknown_type) (GstElement * element, GstPad * pad, GstCaps * caps);
};
/* props */
enum
{
ARG_0,
ARG_THREADED,
};
/* signals */
enum
{
SIGNAL_NEW_DECODED_PAD,
SIGNAL_REMOVED_DECODED_PAD,
SIGNAL_UNKNOWN_TYPE,
LAST_SIGNAL
};
/* this structure is created for all dynamic pads that could get created
* at runtime */
typedef struct
{
gint np_sig_id; /* signal id of new_pad */
gint unlink_sig_id; /* signal id of unlinked */
gint nmp_sig_id; /* signal id of no_more_pads */
GstElement *element; /* the element sending the signal */
GstDecodeBin *decode_bin; /* pointer to ourself */
}
GstDynamic;
static void gst_decode_bin_class_init (GstDecodeBinClass * klass);
static void gst_decode_bin_init (GstDecodeBin * decode_bin);
static void gst_decode_bin_dispose (GObject * object);
static void gst_decode_bin_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * spec);
static void gst_decode_bin_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * spec);
static GstElementStateReturn gst_decode_bin_change_state (GstElement * element);
static void type_found (GstElement * typefind, guint probability,
GstCaps * caps, GstDecodeBin * decode_bin);
static GstElement *try_to_link_1 (GstDecodeBin * decode_bin, GstPad * pad,
GList * factories);
static void close_link (GstElement * element, GstDecodeBin * decode_bin);
static void close_pad_link (GstElement * element, GstPad * pad,
GstCaps * caps, GstDecodeBin * decode_bin, gboolean more);
static void unlinked (GstPad * pad, GstPad * peerpad,
GstDecodeBin * decode_bin);
static GstElementClass *parent_class;
static guint gst_decode_bin_signals[LAST_SIGNAL] = { 0 };
static GstElementDetails gst_decode_bin_details = {
"Decoder Bin",
"Generic/Bin/Decoder",
"Autoplug and decode to raw media",
"Wim Taymans <wim@fluendo.com>"
};
static GType
gst_decode_bin_get_type (void)
{
static GType gst_decode_bin_type = 0;
if (!gst_decode_bin_type) {
static const GTypeInfo gst_decode_bin_info = {
sizeof (GstDecodeBinClass),
NULL,
NULL,
(GClassInitFunc) gst_decode_bin_class_init,
NULL,
NULL,
sizeof (GstDecodeBin),
0,
(GInstanceInitFunc) gst_decode_bin_init,
NULL
};
gst_decode_bin_type =
g_type_register_static (GST_TYPE_BIN, "GstDecodeBin",
&gst_decode_bin_info, 0);
}
return gst_decode_bin_type;
}
static void
gst_decode_bin_class_init (GstDecodeBinClass * klass)
{
GObjectClass *gobject_klass;
GstElementClass *gstelement_klass;
GstBinClass *gstbin_klass;
gobject_klass = (GObjectClass *) klass;
gstelement_klass = (GstElementClass *) klass;
gstbin_klass = (GstBinClass *) klass;
parent_class = g_type_class_ref (gst_bin_get_type ());
gobject_klass->set_property = gst_decode_bin_set_property;
gobject_klass->get_property = gst_decode_bin_get_property;
g_object_class_install_property (gobject_klass, ARG_THREADED,
g_param_spec_boolean ("threaded", "Threaded", "Use threads",
FALSE, G_PARAM_READWRITE));
gst_decode_bin_signals[SIGNAL_NEW_DECODED_PAD] =
g_signal_new ("new-decoded-pad", G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GstDecodeBinClass, new_decoded_pad), NULL, NULL,
gst_play_marshal_VOID__OBJECT_BOOLEAN, G_TYPE_NONE, 2, G_TYPE_OBJECT,
G_TYPE_BOOLEAN);
gst_decode_bin_signals[SIGNAL_REMOVED_DECODED_PAD] =
g_signal_new ("removed-decoded-pad", G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GstDecodeBinClass, removed_decoded_pad), NULL, NULL,
gst_marshal_VOID__OBJECT, G_TYPE_NONE, 1, GST_TYPE_PAD);
gst_decode_bin_signals[SIGNAL_UNKNOWN_TYPE] =
g_signal_new ("unknown-type", G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstDecodeBinClass, unknown_type),
NULL, NULL, gst_marshal_VOID__OBJECT_BOXED, G_TYPE_NONE, 2,
GST_TYPE_PAD, GST_TYPE_CAPS);
gobject_klass->dispose = GST_DEBUG_FUNCPTR (gst_decode_bin_dispose);
gst_element_class_add_pad_template (gstelement_klass,
gst_static_pad_template_get (&decoder_bin_sink_template));
gst_element_class_add_pad_template (gstelement_klass,
gst_static_pad_template_get (&decoder_bin_src_template));
gst_element_class_set_details (gstelement_klass, &gst_decode_bin_details);
gstelement_klass->change_state =
GST_DEBUG_FUNCPTR (gst_decode_bin_change_state);
}
/* check if the bin is dynamic.
*
* If there are no outstanding dynamic connections, the bin is
* considered to be non-dynamic.
*/
static gboolean
gst_decode_bin_is_dynamic (GstDecodeBin * decode_bin)
{
return decode_bin->dynamics != NULL;
}
/* the filter function for selecting the elements we can use in
* autoplugging */
static gboolean
gst_decode_bin_factory_filter (GstPluginFeature * feature,
GstDecodeBin * decode_bin)
{
guint rank;
const gchar *klass;
/* we only care about element factories */
if (!GST_IS_ELEMENT_FACTORY (feature))
return FALSE;
klass = gst_element_factory_get_klass (GST_ELEMENT_FACTORY (feature));
/* only demuxers and decoders can play */
if (strstr (klass, "Demux") == NULL && strstr (klass, "Decoder") == NULL) {
return FALSE;
}
/* only select elements with autoplugging rank */
rank = gst_plugin_feature_get_rank (feature);
if (rank < GST_RANK_MARGINAL)
return FALSE;
return TRUE;
}
/* function used to sort element features */
static gint
compare_ranks (GstPluginFeature * f1, GstPluginFeature * f2)
{
return gst_plugin_feature_get_rank (f2) - gst_plugin_feature_get_rank (f1);
}
static void
print_feature (GstPluginFeature * feature)
{
GST_DEBUG ("%s", gst_plugin_feature_get_name (feature));
}
static void
gst_decode_bin_init (GstDecodeBin * decode_bin)
{
GList *factories;
/* first filter out the interesting element factories */
factories = gst_registry_pool_feature_filter (
(GstPluginFeatureFilter) gst_decode_bin_factory_filter,
FALSE, decode_bin);
/* sort them according to their ranks */
decode_bin->factories = g_list_sort (factories, (GCompareFunc) compare_ranks);
/* do some debugging */
g_list_foreach (decode_bin->factories, (GFunc) print_feature, NULL);
/* we create the typefind element only once */
decode_bin->typefind = gst_element_factory_make ("typefind", "typefind");
if (!decode_bin->typefind) {
g_warning ("can't find typefind element, decodebin will not work");
} else {
/* add the typefind element */
gst_bin_add (GST_BIN (decode_bin), decode_bin->typefind);
/* ghost the sink pad to ourself */
gst_element_add_ghost_pad (GST_ELEMENT (decode_bin),
gst_element_get_pad (decode_bin->typefind, "sink"), "sink");
/* connect a signal to find out when the typefind element found
* a type */
decode_bin->have_type_id =
g_signal_connect (G_OBJECT (decode_bin->typefind), "have_type",
G_CALLBACK (type_found), decode_bin);
}
decode_bin->dynamics = NULL;
}
static void
gst_decode_bin_dispose (GObject * object)
{
GstDecodeBin *decode_bin;
GList *dyns;
decode_bin = GST_DECODE_BIN (object);
g_signal_handler_disconnect (G_OBJECT (decode_bin->typefind),
decode_bin->have_type_id);
gst_bin_remove (GST_BIN (decode_bin), decode_bin->typefind);
g_list_free (decode_bin->factories);
for (dyns = decode_bin->dynamics; dyns; dyns = g_list_next (dyns)) {
GstDynamic *dynamic = (GstDynamic *) dyns->data;
g_free (dynamic);
}
g_list_free (decode_bin->dynamics);
decode_bin->dynamics = NULL;
if (G_OBJECT_CLASS (parent_class)->dispose) {
G_OBJECT_CLASS (parent_class)->dispose (object);
}
}
/* this function runs through the element factories and returns a list
* of all elements that are able to sink the given caps
*/
static GList *
find_compatibles (GstDecodeBin * decode_bin, const GstCaps * caps)
{
GList *factories;
GList *to_try = NULL;
/* loop over all the factories */
for (factories = decode_bin->factories; factories;
factories = g_list_next (factories)) {
GstElementFactory *factory = GST_ELEMENT_FACTORY (factories->data);
const GList *templates;
GList *walk;
/* get the templates from the element factory */
templates = gst_element_factory_get_pad_templates (factory);
for (walk = (GList *) templates; walk; walk = g_list_next (walk)) {
GstPadTemplate *templ = GST_PAD_TEMPLATE (walk->data);
/* we only care about the sink templates */
if (templ->direction == GST_PAD_SINK) {
GstCaps *intersect;
/* try to intersect the caps with the caps of the template */
intersect =
gst_caps_intersect (caps, gst_pad_template_get_caps (templ));
/* check if the intersection is empty */
if (!gst_caps_is_empty (intersect)) {
/* non empty intersection, we can use this element */
to_try = g_list_append (to_try, factory);
}
gst_caps_free (intersect);
}
}
}
return to_try;
}
/* given a pad and a caps from an element, find the list of elements
* that could connect to the pad
*
* If the pad has a raw format, this function will create a ghostpad
* for the pad onto the decodebin.
*
* If no compatible elements could be found, this function will signal
* the unknown_type signal.
*/
static void
close_pad_link (GstElement * element, GstPad * pad, GstCaps * caps,
GstDecodeBin * decode_bin, gboolean more)
{
GList *to_try;
GstStructure *structure;
const gchar *mimetype;
/* the caps is empty, this means the pad has no type, we can only
* decide to fire the unknown_type signal. */
if (caps == NULL || gst_caps_is_empty (caps)) {
g_signal_emit (G_OBJECT (decode_bin),
gst_decode_bin_signals[SIGNAL_UNKNOWN_TYPE], 0, pad, caps);
return;
}
/* the caps is any, this means the pad can be anything and
* we don't know yet */
if (gst_caps_is_any (caps)) {
return;
}
GST_LOG_OBJECT (element, "trying to close %" GST_PTR_FORMAT, caps);
/* FIXME, iterate over more structures? I guess it is possible that
* this pad has some encoded and some raw pads. This code will fail
* then if the first structure is not the raw type... */
structure = gst_caps_get_structure (caps, 0);
mimetype = gst_structure_get_name (structure);
/* first see if this is raw. If the type is raw, we can
* create a ghostpad for this pad. */
if (g_str_has_prefix (mimetype, "video/x-raw") ||
g_str_has_prefix (mimetype, "audio/x-raw")) {
gchar *padname;
GstPad *ghost;
/* make a unique name for this new pad */
padname = g_strdup_printf ("src%d", decode_bin->numpads);
decode_bin->numpads++;
/* make it a ghostpad */
ghost = gst_element_add_ghost_pad (GST_ELEMENT (decode_bin), pad, padname);
GST_LOG_OBJECT (element, "closed pad %s", padname);
/* our own signal with an extra flag that this is the only pad */
g_signal_emit (G_OBJECT (decode_bin),
gst_decode_bin_signals[SIGNAL_NEW_DECODED_PAD], 0, ghost, !more);
g_free (padname);
return;
}
if (gst_caps_get_size (caps) == 1) {
/* then continue plugging, first find all compatible elements */
to_try = find_compatibles (decode_bin, caps);
if (to_try == NULL) {
/* no compatible elements, fire the unknown_type signal, we cannot go
* on */
g_signal_emit (G_OBJECT (decode_bin),
gst_decode_bin_signals[SIGNAL_UNKNOWN_TYPE], 0, pad, caps);
return;
}
try_to_link_1 (decode_bin, pad, to_try);
} else {
GST_LOG_OBJECT (element, "multiple possibilities, delaying");
}
}
/* given a list of element factories, try to link one of the factories
* to the given pad */
static GstElement *
try_to_link_1 (GstDecodeBin * decode_bin, GstPad * pad, GList * factories)
{
GList *walk;
/* loop over the factories */
for (walk = factories; walk; walk = g_list_next (walk)) {
GstElementFactory *factory = GST_ELEMENT_FACTORY (walk->data);
GstElement *element;
gboolean ret;
GST_DEBUG_OBJECT (decode_bin, "trying to link %s",
gst_plugin_feature_get_name (GST_PLUGIN_FEATURE (factory)));
/* make an element from the factory first */
element = gst_element_factory_create (factory, NULL);
if (element == NULL) {
/* hmm, strange. Like with all things in live, let's move on.. */
GST_WARNING_OBJECT (decode_bin, "could not create an element from %s",
gst_plugin_feature_get_name (GST_PLUGIN_FEATURE (factory)));
continue;
}
/* now add the element to the bin first */
GST_DEBUG_OBJECT (decode_bin, "adding %s", gst_element_get_name (element));
gst_bin_add (GST_BIN (decode_bin), element);
/* set to ready first so it can do negotiation */
gst_element_set_state (element, GST_STATE_READY);
/* keep out own list of elements */
decode_bin->elements = g_list_prepend (decode_bin->elements, element);
/* try to link the given pad to a sinkpad */
/* FIXME, find the sinkpad by looping over the pads instead of
* looking it up by name */
ret = gst_pad_link (pad, gst_element_get_pad (element, "sink"));
if (ret) {
const gchar *klass;
GstElementFactory *factory;
guint sig;
GST_DEBUG_OBJECT (decode_bin, "linked on pad %s:%s",
GST_DEBUG_PAD_NAME (pad));
/* The link worked, now figure out what it was that we connected */
factory = gst_element_get_factory (element);
klass = gst_element_factory_get_klass (factory);
/* check if we can use threads */
if (decode_bin->threaded) {
if (strstr (klass, "Demux") != NULL) {
/* FIXME, do something with threads here. Not sure that it
* really matters here but in general it is better to preroll
* on encoded data from the muxer than on raw encoded streams
* because that would consume less memory. */
}
}
/* make sure we catch unlink signals */
sig = g_signal_connect (G_OBJECT (pad), "unlinked",
G_CALLBACK (unlinked), decode_bin);
/* keep a ref to the signal id so that we can disconnect the signal callback */
g_object_set_data (G_OBJECT (pad), "unlinked_id", GINT_TO_POINTER (sig));
/* now that we added the element we can try to continue autoplugging
* on it until we have a raw type */
close_link (element, decode_bin);
/* change the state of the element to that of the parent */
gst_element_sync_state_with_parent (element);
return element;
} else {
GST_DEBUG_OBJECT (decode_bin, "link failed on pad %s:%s",
GST_DEBUG_PAD_NAME (pad));
/* this element did not work, remove it again and continue trying
* other elements */
gst_bin_remove (GST_BIN (decode_bin), element);
}
}
return NULL;
}
static GstPad *
get_our_ghost_pad (GstDecodeBin * decode_bin, GstPad * pad)
{
GList *ghostpads;
if (pad == NULL || !GST_PAD_IS_SRC (pad)) {
GST_DEBUG_OBJECT (decode_bin, "pad NULL or not SRC pad");
return NULL;
}
if (GST_IS_GHOST_PAD (pad)) {
GstElement *parent = gst_pad_get_parent (pad);
GST_DEBUG_OBJECT (decode_bin, "pad parent %s",
gst_element_get_name (parent));
if (parent == GST_ELEMENT (decode_bin)) {
GST_DEBUG_OBJECT (decode_bin, "pad is our ghostpad");
return pad;
} else {
GST_DEBUG_OBJECT (decode_bin, "pad is ghostpad but not ours");
return NULL;
}
}
GST_DEBUG_OBJECT (decode_bin, "looping over ghostpads");
ghostpads = gst_pad_get_ghost_pad_list (pad);
while (ghostpads) {
GstPad *ghostpad;
ghostpad = get_our_ghost_pad (decode_bin, GST_PAD (ghostpads->data));
if (ghostpad)
return ghostpad;
ghostpads = g_list_next (ghostpads);
}
GST_DEBUG_OBJECT (decode_bin, "done looping over ghostpads, nothing found");
return NULL;
}
/* remove all downstream elements starting from the given pad.
* Also make sure to remove the ghostpad we created for the raw
* decoded stream.
*/
static void
remove_element_chain (GstDecodeBin * decode_bin, GstPad * pad)
{
GList *int_links;
GstElement *elem = gst_pad_get_parent (pad);
GST_DEBUG_OBJECT (decode_bin, "%s:%s", GST_DEBUG_PAD_NAME (pad));
/* remove all elements linked to this pad up to the ghostpad
* that we created for this stream */
for (int_links = gst_pad_get_internal_links (pad);
int_links; int_links = g_list_next (int_links)) {
GstPad *pad;
GstPad *ghostpad;
GstPad *peer;
pad = GST_PAD (int_links->data);
GST_DEBUG_OBJECT (decode_bin, "inspecting internal pad %s:%s",
GST_DEBUG_PAD_NAME (pad));
ghostpad = get_our_ghost_pad (decode_bin, pad);
if (ghostpad) {
GST_DEBUG_OBJECT (decode_bin, "found our ghost pad %s:%s for %s:%s",
GST_DEBUG_PAD_NAME (ghostpad), GST_DEBUG_PAD_NAME (pad));
g_signal_emit (G_OBJECT (decode_bin),
gst_decode_bin_signals[SIGNAL_REMOVED_DECODED_PAD], 0, ghostpad);
gst_element_remove_pad (GST_ELEMENT (decode_bin), ghostpad);
continue;
} else {
GST_DEBUG_OBJECT (decode_bin, "not one of our ghostpads");
}
peer = gst_pad_get_peer (pad);
if (peer == NULL)
continue;
GST_DEBUG_OBJECT (decode_bin, "internal pad %s:%s linked to pad %s:%s",
GST_DEBUG_PAD_NAME (pad), GST_DEBUG_PAD_NAME (peer));
if (gst_pad_get_real_parent (peer) != GST_ELEMENT (decode_bin)) {
GST_DEBUG_OBJECT (decode_bin, "dead end pad %s:%s",
GST_DEBUG_PAD_NAME (peer));
} else {
GST_DEBUG_OBJECT (decode_bin, "recursing element %s on pad %s:%s",
gst_element_get_name (elem), GST_DEBUG_PAD_NAME (pad));
remove_element_chain (decode_bin, peer);
}
}
GST_DEBUG_OBJECT (decode_bin, "removing %s", gst_element_get_name (elem));
gst_bin_remove (GST_BIN (decode_bin), elem);
}
/* This function will be called when a dynamic pad is created on an element.
* We try to continue autoplugging on this new pad. */
static void
new_pad (GstElement * element, GstPad * pad, GstDynamic * dynamic)
{
GstDecodeBin *decode_bin = dynamic->decode_bin;
/* see if any more pending dynamic connections exist */
gboolean more = gst_decode_bin_is_dynamic (decode_bin);
close_pad_link (element, pad, gst_pad_get_caps (pad), decode_bin, more);
}
/* this signal is fired when an element signals the no_more_pads signal.
* This means that the element will not generate more dynamic pads and
* we can remove the element from the list of dynamic elements. When we
* have no more dynamic elements in the pipeline, we can fire a no_more_pads
* signal ourselves. */
static void
no_more_pads (GstElement * element, GstDynamic * dynamic)
{
GstDecodeBin *decode_bin = dynamic->decode_bin;
GST_DEBUG_OBJECT (decode_bin, "no more pads on element %s",
gst_element_get_name (element));
/* disconnect signals */
g_signal_handler_disconnect (G_OBJECT (dynamic->element), dynamic->np_sig_id);
g_signal_handler_disconnect (G_OBJECT (dynamic->element),
dynamic->nmp_sig_id);
/* remove the element from the list of dynamic elements */
decode_bin->dynamics = g_list_remove (decode_bin->dynamics, dynamic);
g_free (dynamic);
/* if we have no more dynamic elements, we have no chance of creating
* more pads, so we fire the no_more_pads signal */
if (decode_bin->dynamics == NULL) {
GST_DEBUG_OBJECT (decode_bin,
"no more dynamic elements, signaling no_more_pads");
gst_element_no_more_pads (GST_ELEMENT (decode_bin));
} else {
GST_DEBUG_OBJECT (decode_bin, "we have more dynamic elements");
}
}
/* This function will be called when a pad is disconnected for some reason */
static void
unlinked (GstPad * pad, GstPad * peerpad, GstDecodeBin * decode_bin)
{
GList *walk;
GstDynamic *dyn;
GstElement *element;
/* inactivate pad */
gst_pad_set_active (pad, FALSE);
/* remove all elements linked to the peerpad */
remove_element_chain (decode_bin, peerpad);
/* if an element removes two pads, then we don't want this twice */
element = gst_pad_get_parent (pad);
for (walk = decode_bin->dynamics; walk != NULL; walk = walk->next) {
dyn = walk->data;
if (dyn->element == element)
return;
}
GST_DEBUG_OBJECT (decode_bin, "pad removal while alive - chained?");
/* re-setup dynamic plugging */
dyn = g_new0 (GstDynamic, 1);
dyn->np_sig_id = g_signal_connect (G_OBJECT (element), "new-pad",
G_CALLBACK (new_pad), dyn);
dyn->nmp_sig_id = g_signal_connect (G_OBJECT (element), "no-more-pads",
G_CALLBACK (no_more_pads), dyn);
dyn->element = element;
dyn->decode_bin = decode_bin;
/* and add this element to the dynamic elements */
decode_bin->dynamics = g_list_prepend (decode_bin->dynamics, dyn);
}
/* this function inspects the given element and tries to connect something
* on the srcpads. If there are dynamic pads, it sets up a signal handler to
* continue autoplugging when they become available */
static void
close_link (GstElement * element, GstDecodeBin * decode_bin)
{
GList *pads;
gboolean dynamic = FALSE;
GList *to_connect = NULL;
gboolean more;
GST_DEBUG_OBJECT (decode_bin, "closing links with element %s",
gst_element_get_name (element));
/* loop over all the padtemplates */
for (pads = gst_element_get_pad_template_list (element); pads;
pads = g_list_next (pads)) {
GstPadTemplate *templ = GST_PAD_TEMPLATE (pads->data);
const gchar *templ_name;
/* we are only interested in source pads */
if (GST_PAD_TEMPLATE_DIRECTION (templ) != GST_PAD_SRC)
continue;
templ_name = GST_PAD_TEMPLATE_NAME_TEMPLATE (templ);
GST_DEBUG_OBJECT (decode_bin, "got a source pad template %s", templ_name);
/* figure out what kind of pad this is */
switch (GST_PAD_TEMPLATE_PRESENCE (templ)) {
case GST_PAD_ALWAYS:
{
/* get the pad that we need to autoplug */
GstPad *pad = gst_element_get_pad (element, templ_name);
if (pad) {
GST_DEBUG_OBJECT (decode_bin, "got the pad for always template %s",
templ_name);
/* here is the pad, we need to autoplug it */
to_connect = g_list_prepend (to_connect, pad);
} else {
/* strange, pad is marked as always but it's not
* there. Fix the element */
GST_WARNING_OBJECT (decode_bin,
"could not get the pad for always template %s", templ_name);
}
break;
}
case GST_PAD_SOMETIMES:
{
/* try to get the pad to see if it is already created or
* not */
GstPad *pad = gst_element_get_pad (element, templ_name);
if (pad) {
GST_DEBUG_OBJECT (decode_bin, "got the pad for sometimes template %s",
templ_name);
/* the pad is created, we need to autoplug it */
to_connect = g_list_prepend (to_connect, pad);
} else {
GST_DEBUG_OBJECT (decode_bin,
"did not get the sometimes pad of template %s", templ_name);
/* we have an element that will create dynamic pads */
dynamic = TRUE;
}
break;
}
case GST_PAD_REQUEST:
/* ignore request pads */
GST_DEBUG_OBJECT (decode_bin, "ignoring request padtemplate %s",
templ_name);
break;
}
}
if (dynamic) {
GstDynamic *dyn;
GST_DEBUG_OBJECT (decode_bin, "got a dynamic element here");
/* ok, this element has dynamic pads, set up the signal handlers to be
* notified of them */
dyn = g_new0 (GstDynamic, 1);
dyn->np_sig_id = g_signal_connect (G_OBJECT (element), "new-pad",
G_CALLBACK (new_pad), dyn);
dyn->nmp_sig_id = g_signal_connect (G_OBJECT (element), "no-more-pads",
G_CALLBACK (no_more_pads), dyn);
dyn->element = element;
dyn->decode_bin = decode_bin;
/* and add this element to the dynamic elements */
decode_bin->dynamics = g_list_prepend (decode_bin->dynamics, dyn);
}
/* Check if this is an element with more than 1 pad. If this element
* has more than 1 pad, we need to be carefull not to signal the
* no_more_pads signal after connecting the first pad. */
more = g_list_length (to_connect) > 1;
/* now loop over all the pads we need to connect */
for (pads = to_connect; pads; pads = g_list_next (pads)) {
GstPad *pad = GST_PAD (pads->data);
/* we have more pads if we have more than 1 pad to connect or
* dynamics. If we have only 1 pad and no dynamics, more will be
* set to FALSE and the no-more-pads signal will be fired. Note
* that this can change after the close_pad_link call. */
more |= gst_decode_bin_is_dynamic (decode_bin);
GST_DEBUG_OBJECT (decode_bin, "closing pad link for %s",
gst_pad_get_name (pad));
/* continue autoplugging on the pads */
close_pad_link (element, pad, gst_pad_get_caps (pad), decode_bin, more);
}
g_list_free (to_connect);
}
/* this is the signal handler for the typefind element have_type signal.
* It tries to continue autoplugging on the typefind src pad */
static void
type_found (GstElement * typefind, guint probability, GstCaps * caps,
GstDecodeBin * decode_bin)
{
gboolean dynamic;
GST_DEBUG_OBJECT (decode_bin, "typefind found caps %" GST_PTR_FORMAT, caps);
/* autoplug the new pad with the caps that the signal gave us. */
close_pad_link (typefind, gst_element_get_pad (typefind, "src"), caps,
decode_bin, FALSE);
dynamic = gst_decode_bin_is_dynamic (decode_bin);
if (dynamic == FALSE) {
GST_DEBUG_OBJECT (decode_bin, "we have no dynamic elements anymore");
/* if we have no dynamic elements, we know that no new pads
* will be created and we can signal out no_more_pads signal */
gst_element_no_more_pads (GST_ELEMENT (decode_bin));
} else {
/* more dynamic elements exist that could create new pads */
GST_DEBUG_OBJECT (decode_bin, "we have more dynamic elements");
}
}
static void
gst_decode_bin_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
GstDecodeBin *decode_bin;
g_return_if_fail (GST_IS_DECODE_BIN (object));
decode_bin = GST_DECODE_BIN (object);
switch (prop_id) {
case ARG_THREADED:
decode_bin->threaded = g_value_get_boolean (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_decode_bin_get_property (GObject * object, guint prop_id, GValue * value,
GParamSpec * pspec)
{
GstDecodeBin *decode_bin;
g_return_if_fail (GST_IS_DECODE_BIN (object));
decode_bin = GST_DECODE_BIN (object);
switch (prop_id) {
case ARG_THREADED:
g_value_set_boolean (value, decode_bin->threaded);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static GstElementStateReturn
gst_decode_bin_change_state (GstElement * element)
{
GstElementStateReturn ret;
GstDecodeBin *decode_bin;
gint transition;
decode_bin = GST_DECODE_BIN (element);
transition = GST_STATE_TRANSITION (element);
ret = GST_ELEMENT_CLASS (parent_class)->change_state (element);
if (ret != GST_STATE_SUCCESS) {
return ret;
}
switch (transition) {
case GST_STATE_NULL_TO_READY:
decode_bin->numpads = 0;
decode_bin->threaded = FALSE;
decode_bin->dynamics = NULL;
break;
case GST_STATE_READY_TO_PAUSED:
case GST_STATE_PAUSED_TO_PLAYING:
case GST_STATE_PLAYING_TO_PAUSED:
case GST_STATE_PAUSED_TO_READY:
case GST_STATE_READY_TO_NULL:
break;
default:
break;
}
return ret;
}
static gboolean
plugin_init (GstPlugin * plugin)
{
GST_DEBUG_CATEGORY_INIT (gst_decode_bin_debug, "decodebin", 0, "decoder bin");
return gst_element_register (plugin, "decodebin", GST_RANK_NONE,
GST_TYPE_DECODE_BIN);
}
GST_PLUGIN_DEFINE (GST_VERSION_MAJOR,
GST_VERSION_MINOR,
"decodebin",
"decoder bin", plugin_init, VERSION, GST_LICENSE, GST_PACKAGE, GST_ORIGIN)