]> git.saurik.com Git - wxWidgets.git/blobdiff - src/unix/mediactrl.cpp
check that the version of __sync_sub_and_fetch that returns a value is supported...
[wxWidgets.git] / src / unix / mediactrl.cpp
index 3dfbadf6bc23bdc6d5904809a275d59423f745d9..2a333c38185f579c36c84bc9593c3e920968b441 100644 (file)
@@ -1,6 +1,6 @@
 /////////////////////////////////////////////////////////////////////////////
 /////////////////////////////////////////////////////////////////////////////
-// Name:        unix/mediactrl.cpp
-// Purpose:     Built-in Media Backends for Unix
+// Name:        src/unix/mediactrl.cpp
+// Purpose:     GStreamer backend for Unix
 // Author:      Ryan Norton <wxprojects@comcast.net>
 // Modified by:
 // Created:     02/04/05
 // Author:      Ryan Norton <wxprojects@comcast.net>
 // Modified by:
 // Created:     02/04/05
 // Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////
 
 // Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////
 
-//===========================================================================
-//  DECLARATIONS
-//===========================================================================
-
-//---------------------------------------------------------------------------
-// Pre-compiled header stuff
-//---------------------------------------------------------------------------
-
-#if defined(__GNUG__) && !defined(NO_GCC_PRAGMA)
-#pragma implementation "mediactrl.h"
-#endif
-
 // For compilers that support precompilation, includes "wx.h".
 #include "wx/wxprec.h"
 
 // For compilers that support precompilation, includes "wx.h".
 #include "wx/wxprec.h"
 
-#ifdef __BORLANDC__
-#pragma hdrstop
-#endif
-
-//---------------------------------------------------------------------------
-// Includes
-//---------------------------------------------------------------------------
-#include "wx/mediactrl.h"
-
-//---------------------------------------------------------------------------
-// Compilation guard
-//---------------------------------------------------------------------------
 #if wxUSE_MEDIACTRL
 
 #if wxUSE_MEDIACTRL
 
-//===========================================================================
-//  BACKEND DECLARATIONS
-//===========================================================================
+#include "wx/mediactrl.h"
 
 
-//---------------------------------------------------------------------------
-//
-//  wxGStreamerMediaBackend
-//
-// This won't compile/work without a little work yet...
-// Uses nanoseconds...
-//---------------------------------------------------------------------------
 #if wxUSE_GSTREAMER
 
 #if wxUSE_GSTREAMER
 
-//---------------------------------------------------------------------------
-//  GStreamer Includes
-//---------------------------------------------------------------------------
-#include <gst/gst.h>
-#include <gst/xoverlay/xoverlay.h>
+#include <gst/gst.h>                // main gstreamer header
 
 
-#include <string.h> //strstr
+// xoverlay/video stuff, gst-gconf for 0.8
+#if GST_VERSION_MAJOR > 0 || GST_VERSION_MINOR >= 10
+#   include <gst/interfaces/xoverlay.h>
+#else
+#   include <gst/xoverlay/xoverlay.h>
+#   include <gst/gconf/gconf.h>        // gstreamer glib configuration
+#endif
 
 
-#include "wx/log.h"
+#ifndef  WX_PRECOMP
+    #include "wx/log.h"             // wxLogDebug/wxLogSysError/wxLogTrace
+    #include "wx/app.h"             // wxTheApp->argc, wxTheApp->argv
+    #include "wx/timer.h"           // wxTimer
+#endif
+
+#include "wx/thread.h"              // wxMutex/wxMutexLocker
 
 #ifdef __WXGTK__
 
 #ifdef __WXGTK__
-    //for <gdk/gdkx.h>/related for GDK_WINDOW_XWINDOW
-#   include "wx/gtk/win_gtk.h"
+    #include <gtk/gtk.h>
+#    include <gdk/gdkx.h>           // for GDK_WINDOW_XWINDOW
+#endif
+
+//-----------------------------------------------------------------------------
+// Discussion of internals
+//-----------------------------------------------------------------------------
+
+/*
+   This is the GStreamer backend for unix. Currently we require 0.8 or
+   0.10. Here we use the "playbin" GstElement for ease of use.
+
+   Note that now we compare state change functions to GST_STATE_FAILURE
+   now rather than GST_STATE_SUCCESS as newer gstreamer versions return
+   non-success values for returns that are otherwise successful but not
+   immediate.
+
+   Also this probably doesn't work with anything other than wxGTK at the
+   moment but with a tad bit of work it could theorectically work in
+   straight wxX11 et al.
+
+   One last note is that resuming from pausing/seeking can result
+   in erratic video playback (GStreamer-based bug, happens in totem as well)
+   - this is better in 0.10, however. One thing that might make it worse
+   here is that we don't preserve the aspect ratio of the video and stretch
+   it to the whole window.
+
+   Note that there are some things used here that could be undocumented -
+   for reference see the media player Kiss and Totem as well as some
+   other sources. There was a backend for a kde media player as well
+   that attempted thread-safety...
+
+   Then there is the issue of m_asynclock. This serves several purposes:
+   1) It prevents the C callbacks from sending wx state change events
+      so that we don't get duplicate ones in 0.8
+   2) It makes the sync and async handlers in 0.10 not drop any
+      messages so that while we are polling it we get the messages in
+      SyncStateChange instead of the queue.
+   3) Keeps the pausing in Stop() synchronous
+
+   RN: Note that I've tried to follow the wxGTK conventions here as close
+   as possible. In the implementation the C Callbacks come first, then
+   the internal functions, then the public ones. Set your vi to 80
+   characters people :).
+*/
+
+//=============================================================================
+//  Declarations
+//=============================================================================
+
+//-----------------------------------------------------------------------------
+//  GStreamer (most version compatability) macros
+//-----------------------------------------------------------------------------
+
+// In 0.9 there was a HUGE change to GstQuery and the
+// gst_element_query function changed dramatically and split off
+// into two seperate ones
+#if GST_VERSION_MAJOR == 0 && GST_VERSION_MINOR <= 8
+#    define wxGst_element_query_duration(e, f, p) \
+                gst_element_query(e, GST_QUERY_TOTAL, f, p)
+#    define wxGst_element_query_position(e, f, p) \
+                gst_element_query(e, GST_QUERY_POSITION, f, p)
+#elif GST_VERSION_MAJOR == 0 && GST_VERSION_MINOR == 9
+// However, the actual 0.9 version has a slightly different definition
+// and instead of gst_element_query_duration it has two parameters to
+// gst_element_query_position instead
+#    define wxGst_element_query_duration(e, f, p) \
+                gst_element_query_position(e, f, 0, p)
+#    define wxGst_element_query_position(e, f, p) \
+                gst_element_query_position(e, f, p, 0)
+#else
+#    define wxGst_element_query_duration \
+                gst_element_query_duration
+#    define wxGst_element_query_position \
+                gst_element_query_position
+#endif
+
+// Other 0.10 macros
+#if GST_VERSION_MAJOR > 0 || GST_VERSION_MINOR >= 10
+#   define GST_STATE_FAILURE GST_STATE_CHANGE_FAILURE
+#   define GST_STATE_SUCCESS GST_STATE_CHANGE_SUCCESS
+#   define GstElementState GstState
+#   define gst_gconf_get_default_video_sink() \
+        gst_element_factory_make ("gconfvideosink", "video-sink");
+#   define gst_gconf_get_default_audio_sink() \
+        gst_element_factory_make ("gconfaudiosink", "audio-sink");
 #endif
 
 #endif
 
-class WXDLLIMPEXP_MEDIA wxGStreamerMediaBackend : public wxMediaBackend
+// Max wait time for element state waiting - GST_CLOCK_TIME_NONE for inf
+#define wxGSTREAMER_TIMEOUT (100 * GST_MSECOND) // Max 100 milliseconds
+
+//-----------------------------------------------------------------------------
+//  wxLogTrace mask string
+//-----------------------------------------------------------------------------
+#define wxTRACE_GStreamer wxT("GStreamer")
+
+//-----------------------------------------------------------------------------
+//
+//  wxGStreamerMediaBackend
+//
+//-----------------------------------------------------------------------------
+class WXDLLIMPEXP_MEDIA
+    wxGStreamerMediaBackend : public wxMediaBackendCommonBase
 {
 public:
 
     wxGStreamerMediaBackend();
 {
 public:
 
     wxGStreamerMediaBackend();
-    ~wxGStreamerMediaBackend();
+    virtual ~wxGStreamerMediaBackend();
 
     virtual bool CreateControl(wxControl* ctrl, wxWindow* parent,
                                      wxWindowID id,
 
     virtual bool CreateControl(wxControl* ctrl, wxWindow* parent,
                                      wxWindowID id,
@@ -100,41 +173,791 @@ public:
     virtual double GetPlaybackRate();
     virtual bool SetPlaybackRate(double dRate);
 
     virtual double GetPlaybackRate();
     virtual bool SetPlaybackRate(double dRate);
 
-    void Cleanup();
+    virtual wxLongLong GetDownloadProgress();
+    virtual wxLongLong GetDownloadTotal();
+
+    virtual bool SetVolume(double dVolume);
+    virtual double GetVolume();
+
+    //------------implementation from now on-----------------------------------
+    bool DoLoad(const wxString& locstring);
+    wxMediaCtrl* GetControl() { return m_ctrl; } // for C Callbacks
+    void HandleStateChange(GstElementState oldstate, GstElementState newstate);
+    bool QueryVideoSizeFromElement(GstElement* element);
+    bool QueryVideoSizeFromPad(GstPad* caps);
+    void SetupXOverlay();
+    bool SyncStateChange(GstElement* element, GstElementState state,
+                         gint64 llTimeout = wxGSTREAMER_TIMEOUT);
+    bool TryAudioSink(GstElement* audiosink);
+    bool TryVideoSink(GstElement* videosink);
+
+    GstElement*     m_playbin;      // GStreamer media element
+    wxSize          m_videoSize;    // Cached actual video size
+    double          m_dRate;        // Current playback rate -
+                                    // see GetPlaybackRate for notes
+    wxLongLong      m_llPausedPos;  // Paused position - see Pause()
+    GstXOverlay*    m_xoverlay;     // X Overlay that contains the GST video
+    wxMutex         m_asynclock;    // See "discussion of internals"
+    class wxGStreamerMediaEventHandler* m_eventHandler; // see below
+
+    friend class wxGStreamerMediaEventHandler;
+    friend class wxGStreamerLoadWaitTimer;
+    DECLARE_DYNAMIC_CLASS(wxGStreamerMediaBackend);
+};
 
 
-    static void OnFinish(GstElement *play,  gpointer data);
-    static void OnError (GstElement *play,  GstElement *src,
-                         GError     *err,   gchar      *debug,
-                         gpointer    data);
+//-----------------------------------------------------------------------------
+// wxGStreamerMediaEventHandler
+//
+// OK, this will take an explanation - basically gstreamer callbacks
+// are issued in a seperate thread, and in this thread we may not set
+// the state of the playbin, so we need to send a wx event in that
+// callback so that we set the state of the media and other stuff
+// like GUI calls.
+//-----------------------------------------------------------------------------
+class wxGStreamerMediaEventHandler : public wxEvtHandler
+{
+    public:
+    wxGStreamerMediaEventHandler(wxGStreamerMediaBackend* be) : m_be(be)
+    {
+        this->Connect(wxID_ANY, wxEVT_MEDIA_FINISHED,
+           wxMediaEventHandler(wxGStreamerMediaEventHandler::OnMediaFinish));
+    }
 
 
-    GstElement* m_player;       //GStreamer media element
-    GstElement* m_audiosink;
-    GstElement* m_videosink;
+    void OnMediaFinish(wxMediaEvent& event);
 
 
-    DECLARE_DYNAMIC_CLASS(wxGStreamerMediaBackend);
+    wxGStreamerMediaBackend* m_be;
 };
 
 };
 
+//=============================================================================
+// Implementation
+//=============================================================================
+
+IMPLEMENT_DYNAMIC_CLASS(wxGStreamerMediaBackend, wxMediaBackend)
+
+//-----------------------------------------------------------------------------
+//
+// C Callbacks
+//
+//-----------------------------------------------------------------------------
+
+//-----------------------------------------------------------------------------
+// "expose_event" from m_ctrl->m_wxwindow
+//
+// Handle GTK expose event from our window - here we hopefully
+// redraw the video in the case of pausing and other instances...
+// (Returns TRUE to pass to other handlers, FALSE if not)
+//
+// TODO: Do a DEBUG_MAIN_THREAD/install_idle_handler here?
+//-----------------------------------------------------------------------------
+#ifdef __WXGTK__
+extern "C" {
+static gboolean gtk_window_expose_callback(GtkWidget *widget,
+                                           GdkEventExpose *event,
+                                           wxGStreamerMediaBackend *be)
+{
+    if(event->count > 0)
+        return FALSE;
+
+    GdkWindow *window = widget->window;
+
+    // I've seen this reccommended somewhere...
+    // TODO: Is this needed? Maybe it is just cruft...
+    // gst_x_overlay_set_xwindow_id( GST_X_OVERLAY(be->m_xoverlay),
+    //                              GDK_WINDOW_XWINDOW( window ) );
+
+    // If we have actual video.....
+    if(!(be->m_videoSize.x==0&&be->m_videoSize.y==0) &&
+       GST_STATE(be->m_playbin) >= GST_STATE_PAUSED)
+    {
+        // GST Doesn't redraw automatically while paused
+        // Plus, the video sometimes doesn't redraw when it looses focus
+        // or is painted over so we just tell it to redraw...
+        gst_x_overlay_expose(be->m_xoverlay);
+    }
+    else
+    {
+        // draw a black background like some other backends do....
+        gdk_draw_rectangle (window, widget->style->black_gc, TRUE, 0, 0,
+                            widget->allocation.width,
+                            widget->allocation.height);
+    }
+
+    return FALSE;
+}
+}
+#endif // wxGTK
+
+//-----------------------------------------------------------------------------
+// "realize" from m_ctrl->m_wxwindow
+//
+// If the window wasn't realized when Load was called, this is the
+// callback for when it is - the purpose of which is to tell
+// GStreamer to play the video in our control
+//-----------------------------------------------------------------------------
+#ifdef __WXGTK__
+extern "C" {
+static gint gtk_window_realize_callback(GtkWidget* widget,
+                                        wxGStreamerMediaBackend* be)
+{
+    gdk_flush();
+    
+    GdkWindow *window = widget->window;
+    wxASSERT(window);
+
+    gst_x_overlay_set_xwindow_id( GST_X_OVERLAY(be->m_xoverlay),
+                                GDK_WINDOW_XWINDOW( window )
+                                );
+    g_signal_connect (be->GetControl()->m_wxwindow,
+                      "expose_event",
+                      G_CALLBACK(gtk_window_expose_callback), be);
+    return 0;
+}
+}
+#endif // wxGTK
+
+//-----------------------------------------------------------------------------
+// "state-change" from m_playbin/GST_MESSAGE_STATE_CHANGE
+//
+// Called by gstreamer when the state changes - here we
+// send the appropriate corresponding wx event.
+//
+// 0.8 only as HandleStateChange does this in both versions
+//-----------------------------------------------------------------------------
+#if GST_VERSION_MAJOR == 0 && GST_VERSION_MINOR < 10
+extern "C" {
+static void gst_state_change_callback(GstElement *play,
+                                      GstElementState oldstate,
+                                      GstElementState newstate,
+                                      wxGStreamerMediaBackend* be)
+{
+    if(be->m_asynclock.TryLock() == wxMUTEX_NO_ERROR)
+    {
+        be->HandleStateChange(oldstate, newstate);
+        be->m_asynclock.Unlock();
+    }
+}
+}
+#endif // <0.10
+
+//-----------------------------------------------------------------------------
+// "eos" from m_playbin/GST_MESSAGE_EOS
+//
+// Called by gstreamer when the media is done playing ("end of stream")
+//-----------------------------------------------------------------------------
+extern "C" {
+static void gst_finish_callback(GstElement *play,
+                                wxGStreamerMediaBackend* be)
+{
+    wxLogTrace(wxTRACE_GStreamer, wxT("gst_finish_callback"));
+    wxMediaEvent event(wxEVT_MEDIA_FINISHED);
+    be->m_eventHandler->AddPendingEvent(event);
+}
+}
+
+//-----------------------------------------------------------------------------
+// "error" from m_playbin/GST_MESSAGE_ERROR
+//
+// Called by gstreamer when an error is encountered playing the media -
+// We call wxLogTrace in addition wxLogSysError so that we can get it
+// on the command line as well for those who want extra traces.
+//-----------------------------------------------------------------------------
+extern "C" {
+static void gst_error_callback(GstElement *play,
+                               GstElement *src,
+                               GError     *err,
+                               gchar      *debug,
+                               wxGStreamerMediaBackend* be)
+{
+    wxString sError;
+    sError.Printf(wxT("gst_error_callback\n")
+                  wxT("Error Message:%s\nDebug:%s\n"),
+                  (const wxChar*)wxConvUTF8.cMB2WX(err->message),
+                  (const wxChar*)wxConvUTF8.cMB2WX(debug));
+    wxLogTrace(wxTRACE_GStreamer, sError);
+    wxLogSysError(sError);
+}
+}
+
+//-----------------------------------------------------------------------------
+// "notify::caps" from the videopad inside "stream-info" of m_playbin
+//
+// Called by gstreamer when the video caps for the media is ready - currently
+// we use the caps to get the natural size of the video
+//
+// (Undocumented?)
+//-----------------------------------------------------------------------------
+extern "C" {
+static void gst_notify_caps_callback(GstPad* pad,
+                                     GParamSpec* pspec,
+                                     wxGStreamerMediaBackend* be)
+{
+    wxLogTrace(wxTRACE_GStreamer, wxT("gst_notify_caps_callback"));
+    be->QueryVideoSizeFromPad(pad);
+}
+}
+
+//-----------------------------------------------------------------------------
+// "notify::stream-info" from m_playbin
+//
+// Run through the stuff in "stream-info" of m_playbin for a valid
+// video pad, and then attempt to query the video size from it - if not
+// set up an event to do so when ready.
+//
+// Currently unused - now we just query it directly using
+// QueryVideoSizeFromElement.
+//
+// (Undocumented?)
+//-----------------------------------------------------------------------------
+#if GST_VERSION_MAJOR > 0 || GST_VERSION_MINOR >= 10
+extern "C" {
+static void gst_notify_stream_info_callback(GstElement* element,
+                                            GParamSpec* pspec,
+                                            wxGStreamerMediaBackend* be)
+{
+    wxLogTrace(wxTRACE_GStreamer, wxT("gst_notify_stream_info_callback"));
+    be->QueryVideoSizeFromElement(be->m_playbin);
+}
+}
+#endif
+
+//-----------------------------------------------------------------------------
+// "desired-size-changed" from m_xoverlay
+//
+// 0.8-specific this provides us with the video size when it changes -
+// even though we get the caps as well this seems to come before the
+// caps notification does...
+//
+// Note it will return 16,16 for an early-bird value or for audio
+//-----------------------------------------------------------------------------
+#if GST_VERSION_MAJOR == 0 && GST_VERSION_MINOR < 10
+extern "C" {
+static void gst_desired_size_changed_callback(GstElement * play,
+                                              guint width, guint height,
+                                              wxGStreamerMediaBackend* be)
+{
+    if(!(width == 16 && height == 16))
+    {
+        be->m_videoSize.x = width;
+        be->m_videoSize.y = height;
+    }
+    else
+        be->QueryVideoSizeFromElement(be->m_playbin);
+}
+}
+#endif
+
+//-----------------------------------------------------------------------------
+// gst_bus_async_callback [static]
+// gst_bus_sync_callback [static]
+//
+// Called by m_playbin for notifications such as end-of-stream in 0.10 -
+// in previous versions g_signal notifications were used. Because everything
+// in centered in one switch statement though it reminds one of old WinAPI
+// stuff.
+//
+// gst_bus_sync_callback is that sync version that is called on the main GUI
+// thread before the async version that we use to set the xwindow id of the
+// XOverlay (NB: This isn't currently used - see CreateControl()).
+//-----------------------------------------------------------------------------
+#if GST_VERSION_MAJOR > 0 || GST_VERSION_MINOR >= 10
+extern "C" {
+static gboolean gst_bus_async_callback(GstBus* bus,
+                                       GstMessage* message,
+                                       wxGStreamerMediaBackend* be)
+{
+    if(((GstElement*)GST_MESSAGE_SRC(message)) != be->m_playbin)
+        return TRUE;
+    if(be->m_asynclock.TryLock() != wxMUTEX_NO_ERROR)
+        return TRUE;
+
+    switch(GST_MESSAGE_TYPE(message))
+    {
+        case GST_MESSAGE_STATE_CHANGED:
+        {
+            GstState oldstate, newstate, pendingstate;
+            gst_message_parse_state_changed(message, &oldstate,
+                                            &newstate, &pendingstate);
+            be->HandleStateChange(oldstate, newstate);
+            break;
+        }
+        case GST_MESSAGE_EOS:
+        {
+            gst_finish_callback(NULL, be);
+            break;
+        }
+        case GST_MESSAGE_ERROR:
+        {
+            GError* error;
+            gchar* debug;
+            gst_message_parse_error(message, &error, &debug);
+            gst_error_callback(NULL, NULL, error, debug, be);
+            break;
+        }
+        default:
+            break;
+    }
+
+    be->m_asynclock.Unlock();
+    return FALSE; // remove the message from Z queue
+}
+
+static GstBusSyncReply gst_bus_sync_callback(GstBus* bus,
+                                             GstMessage* message,
+                                             wxGStreamerMediaBackend* be)
+{
+    // Pass a non-xwindowid-setting event on to the async handler where it
+    // belongs
+    if (GST_MESSAGE_TYPE (message) != GST_MESSAGE_ELEMENT ||
+        !gst_structure_has_name (message->structure, "prepare-xwindow-id"))
+    {
+        //
+        // NB: Unfortunately, the async callback can be quite
+        // buggy at times and often doesn't get called at all,
+        // so here we are processing it right here in the calling
+        // thread instead of the GUI one...
+        //
+        if(gst_bus_async_callback(bus, message, be))
+            return GST_BUS_PASS;
+        else
+            return GST_BUS_DROP;
+    }
+
+    wxLogTrace(wxTRACE_GStreamer, wxT("Got prepare-xwindow-id"));
+    be->SetupXOverlay();
+    return GST_BUS_DROP; // We handled this message - drop from the queue
+}
+}
+#endif
+
+//-----------------------------------------------------------------------------
+//
+// Private (although not in the C++ sense)  methods
+//
+//-----------------------------------------------------------------------------
+
+//-----------------------------------------------------------------------------
+// wxGStreamerMediaBackend::HandleStateChange
+//
+// Handles a state change event from our C Callback for "state-change" or
+// the async queue in 0.10. (Mostly this is here to avoid locking the
+// the mutex twice...)
+//-----------------------------------------------------------------------------
+void wxGStreamerMediaBackend::HandleStateChange(GstElementState oldstate,
+                                                GstElementState newstate)
+{
+    switch(newstate)
+    {
+        case GST_STATE_PLAYING:
+            wxLogTrace(wxTRACE_GStreamer, wxT("Play event"));
+            QueuePlayEvent();
+            break;
+        case GST_STATE_PAUSED:
+            // For some reason .10 sends a lot of oldstate == newstate
+            // messages - most likely for pending ones - also
+            // !<GST_STATE_PAUSED as we are only concerned
+            if(oldstate < GST_STATE_PAUSED || oldstate == newstate)
+                break;
+            if(wxGStreamerMediaBackend::GetPosition() != 0)
+            {
+                wxLogTrace(wxTRACE_GStreamer, wxT("Pause event"));
+                QueuePauseEvent();
+            }
+            else
+            {
+                wxLogTrace(wxTRACE_GStreamer, wxT("Stop event"));
+                QueueStopEvent();
+            }
+            break;
+       default: // GST_STATE_NULL etc.
+            break;
+    }
+}
+
+//-----------------------------------------------------------------------------
+// wxGStreamerMediaBackend::QueryVideoSizeFromElement
+//
+// Run through the stuff in "stream-info" of element for a valid
+// video pad, and then attempt to query the video size from it - if not
+// set up an event to do so when ready. Return true
+// if we got a valid video pad.
+//-----------------------------------------------------------------------------
+bool wxGStreamerMediaBackend::QueryVideoSizeFromElement(GstElement* element)
+{
+    const GList *list = NULL;
+    g_object_get (G_OBJECT (element), "stream-info", &list, NULL);
+
+    for ( ; list != NULL; list = list->next)
+    {
+        GObject *info = (GObject *) list->data;
+        gint type;
+        GParamSpec *pspec;
+        GEnumValue *val;
+        GstPad *pad = NULL;
+
+        g_object_get (info, "type", &type, NULL);
+        pspec = g_object_class_find_property (
+                        G_OBJECT_GET_CLASS (info), "type");
+        val = g_enum_get_value (G_PARAM_SPEC_ENUM (pspec)->enum_class, type);
+
+        if (!strncasecmp(val->value_name, "video", 5) ||
+            !strncmp(val->value_name, "GST_STREAM_TYPE_VIDEO", 21))
+        {
+            // Newer gstreamer 0.8+ plugins are SUPPOSED to have "object"...
+            // but a lot of old plugins still use "pad" :)
+            pspec = g_object_class_find_property (
+                        G_OBJECT_GET_CLASS (info), "object");
+
+            if (!pspec)
+                g_object_get (info, "pad", &pad, NULL);
+            else
+                g_object_get (info, "object", &pad, NULL);
+
+#if GST_VERSION_MAJOR == 0 && GST_VERSION_MINOR <= 8
+            // Killed in 0.9, presumely because events and such
+            // should be pushed on pads regardless of whether they
+            // are currently linked
+            pad = (GstPad *) GST_PAD_REALIZE (pad);
+            wxASSERT(pad);
+#endif
+
+            if(!QueryVideoSizeFromPad(pad))
+            {
+                // wait for those caps to get ready
+                g_signal_connect(
+                pad,
+                "notify::caps",
+                G_CALLBACK(gst_notify_caps_callback),
+                this);
+            }
+            break;
+        }// end if video
+    }// end searching through info list
+
+    // no video (or extremely delayed stream-info)
+    if(list == NULL)
+    {
+        m_videoSize = wxSize(0,0);
+        return false;
+    }
+
+    return true;
+}
+
+//-----------------------------------------------------------------------------
+// wxGStreamerMediaBackend::QueryVideoSizeFromPad
+//
+// Gets the size of our video (in wxSize) from a GstPad
+//-----------------------------------------------------------------------------
+bool wxGStreamerMediaBackend::QueryVideoSizeFromPad(GstPad* pad)
+{
+    const GstCaps* caps = GST_PAD_CAPS(pad);
+    if ( caps )
+    {
+        const GstStructure *s = gst_caps_get_structure (caps, 0);
+        wxASSERT(s);
+
+        gst_structure_get_int (s, "width", &m_videoSize.x);
+        gst_structure_get_int (s, "height", &m_videoSize.y);
+
+        const GValue *par;
+        par = gst_structure_get_value (s, "pixel-aspect-ratio");
+
+        if (par)
+        {
+            wxLogTrace(wxTRACE_GStreamer,
+                       wxT("pixel-aspect-ratio found in pad"));
+            int num = par->data[0].v_int,
+                den = par->data[1].v_int;
+
+            // TODO: maybe better fraction normalization...
+            if (num > den)
+                m_videoSize.x = (int) ((float) num * m_videoSize.x / den);
+            else
+                m_videoSize.y = (int) ((float) den * m_videoSize.y / num);
+        }
+
+         wxLogTrace(wxTRACE_GStreamer, wxT("Adjusted video size: [%i,%i]"),
+                     m_videoSize.x, m_videoSize.y);
+        return true;
+    } // end if caps
+
+    return false; // not ready/massive failure
+}
+
+//-----------------------------------------------------------------------------
+// wxGStreamerMediaBackend::SetupXOverlay
+//
+// Attempts to set the XWindow id of our GstXOverlay to tell it which
+// window to play video in.
+//-----------------------------------------------------------------------------
+void wxGStreamerMediaBackend::SetupXOverlay()
+{
+    // Use the xoverlay extension to tell gstreamer to play in our window
+#ifdef __WXGTK__
+    if(!GTK_WIDGET_REALIZED(m_ctrl->m_wxwindow))
+    {
+        // Not realized yet - set to connect at realization time
+        g_signal_connect (m_ctrl->m_wxwindow,
+                          "realize",
+                          G_CALLBACK (gtk_window_realize_callback),
+                          this);
+    }
+    else
+    {
+        gdk_flush();
+    
+        GdkWindow *window = m_ctrl->m_wxwindow->window;
+        wxASSERT(window);
+#endif
+
+    gst_x_overlay_set_xwindow_id( GST_X_OVERLAY(m_xoverlay),
+#ifdef __WXGTK__
+                        GDK_WINDOW_XWINDOW( window )
+#else
+                        ctrl->GetHandle()
+#endif
+                                  );
+
+#ifdef __WXGTK__
+    g_signal_connect (m_ctrl->m_wxwindow,
+                        // m_ctrl->m_wxwindow/*m_ctrl->m_widget*/,
+                      "expose_event",
+                      G_CALLBACK(gtk_window_expose_callback), this);
+    } // end if GtkPizza realized
+#endif
+}
 
 
-//+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+//-----------------------------------------------------------------------------
+// wxGStreamerMediaBackend::SyncStateChange
 //
 //
-// wxGStreamerMediaBackend
+// This function is rather complex - basically the idea is that we
+// poll the GstBus of m_playbin until it has reached desiredstate, an error
+// is reached, or there are no more messages left in the GstBus queue.
 //
 //
-//+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+// Returns true if there are no messages left in the queue or
+// the current state reaches the disired state.
+//
+// PRECONDITION: Assumes m_asynclock is Lock()ed
+//-----------------------------------------------------------------------------
+#if GST_VERSION_MAJOR > 0 || GST_VERSION_MINOR >= 10
+bool wxGStreamerMediaBackend::SyncStateChange(GstElement* element,
+                                              GstElementState desiredstate,
+                                              gint64 llTimeout)
+{
+    GstBus* bus = gst_element_get_bus(element);
+    GstMessage* message;
+    bool bBreak = false,
+         bSuccess = false;
+    gint64 llTimeWaited = 0;
 
 
-IMPLEMENT_DYNAMIC_CLASS(wxGStreamerMediaBackend, wxMediaBackend);
+    do
+    {
+#if 1
+        // NB: The GStreamer gst_bus_poll is unfortunately broken and
+        // throws silly critical internal errors (for instance
+        // "message != NULL" when the whole point of it is to
+        // poll for the message in the first place!) so we implement
+        // our own "waiting mechinism"
+        if(gst_bus_have_pending(bus) == FALSE)
+        {
+            if(llTimeWaited >= llTimeout)
+                return true; // Reached timeout... assume success
+            llTimeWaited += 10*GST_MSECOND;
+            wxMilliSleep(10);
+            continue;
+        }
+
+        message = gst_bus_pop(bus);
+#else
+        message = gst_bus_poll(bus, (GstMessageType)
+                           (GST_MESSAGE_STATE_CHANGED |
+                            GST_MESSAGE_ERROR |
+                            GST_MESSAGE_EOS), llTimeout);
+        if(!message)
+            return true;
+#endif
+        if(((GstElement*)GST_MESSAGE_SRC(message)) == element)
+        {
+            switch(GST_MESSAGE_TYPE(message))
+            {
+                case GST_MESSAGE_STATE_CHANGED:
+                {
+                    GstState oldstate, newstate, pendingstate;
+                    gst_message_parse_state_changed(message, &oldstate,
+                                                    &newstate, &pendingstate);
+                    if(newstate == desiredstate)
+                    {
+                        bSuccess = bBreak = true;
+                    }
+                    break;
+                }
+                case GST_MESSAGE_ERROR:
+                {
+                    GError* error;
+                    gchar* debug;
+                    gst_message_parse_error(message, &error, &debug);
+                    gst_error_callback(NULL, NULL, error, debug, this);
+                    bBreak = true;
+                    break;
+                }
+                case GST_MESSAGE_EOS:
+                    wxLogSysError(wxT("Reached end of stream prematurely"));
+                    bBreak = true;
+                    break;
+                default:
+                    break; // not handled
+            }
+        }
+
+        gst_message_unref(message);
+    }while(!bBreak);
+
+    return bSuccess;
+}
+#else // 0.8 implementation
+bool wxGStreamerMediaBackend::SyncStateChange(GstElement* element,
+                                              GstElementState desiredstate,
+                                              gint64 llTimeout)
+{
+    gint64 llTimeWaited = 0;
+    while(GST_STATE(element) != desiredstate)
+    {
+        if(llTimeWaited >= llTimeout)
+            break;
+        llTimeWaited += 10*GST_MSECOND;
+        wxMilliSleep(10);
+    }
 
 
+    return llTimeWaited != llTimeout;
+}
+#endif
+
+//-----------------------------------------------------------------------------
+// wxGStreamerMediaBackend::TryAudioSink
+// wxGStreamerMediaBackend::TryVideoSink
+//
+// Uses various means to determine whether a passed in video/audio sink
+// if suitable for us - if it is not we return false and unref the
+// inappropriate sink.
+//-----------------------------------------------------------------------------
+bool wxGStreamerMediaBackend::TryAudioSink(GstElement* audiosink)
+{
+    if( !GST_IS_ELEMENT(audiosink) )
+    {
+        if(G_IS_OBJECT(audiosink))
+            g_object_unref(audiosink);
+        return false;
+    }
+
+    return true;
+}
+
+bool wxGStreamerMediaBackend::TryVideoSink(GstElement* videosink)
+{
+    // Check if the video sink either is an xoverlay or might contain one...
+    if( !GST_IS_BIN(videosink) && !GST_IS_X_OVERLAY(videosink) )
+    {
+        if(G_IS_OBJECT(videosink))
+            g_object_unref(videosink);
+        return false;
+    }
+
+    // Make our video sink and make sure it supports the x overlay interface
+    // the x overlay enables us to put the video in our control window
+    // (i.e. we NEED it!) - also connect to the natural video size change event
+    if( GST_IS_BIN(videosink) )
+        m_xoverlay = (GstXOverlay*)
+                        gst_bin_get_by_interface (GST_BIN (videosink),
+                                                  GST_TYPE_X_OVERLAY);
+    else
+        m_xoverlay = (GstXOverlay*) videosink;
+
+    if ( !GST_IS_X_OVERLAY(m_xoverlay) )
+    {
+        g_object_unref(videosink);
+        return false;
+    }
+
+    return true;
+}
+
+//-----------------------------------------------------------------------------
+// wxGStreamerMediaEventHandler::OnMediaFinish
+//
+// Called when the media is about to stop
+//-----------------------------------------------------------------------------
+void wxGStreamerMediaEventHandler::OnMediaFinish(wxMediaEvent& WXUNUSED(event))
+{
+    // (RN - I have no idea why I thought this was good behaviour....
+    // maybe it made sense for streaming/nonseeking data but
+    // generally it seems like a really bad idea) -
+    if(m_be->SendStopEvent())
+    {
+        // Stop the media (we need to set it back to paused
+        // so that people can get the duration et al.
+        // and send the finish event (luckily we can "Sync" it out... LOL!)
+        // (We don't check return values here because we can't really do
+        //  anything...)
+        wxMutexLocker lock(m_be->m_asynclock);
+
+        // Set element to ready+sync it
+        gst_element_set_state (m_be->m_playbin, GST_STATE_READY);
+        m_be->SyncStateChange(m_be->m_playbin, GST_STATE_READY);
+
+        // Now set it to paused + update pause pos to 0 and
+        // Sync that as well (note that we don't call Stop() here
+        // due to mutex issues)
+        gst_element_set_state (m_be->m_playbin, GST_STATE_PAUSED);
+        m_be->SyncStateChange(m_be->m_playbin, GST_STATE_PAUSED);
+        m_be->m_llPausedPos = 0;
+
+        // Finally, queue the finish event
+        m_be->QueueFinishEvent();
+    }
+}
+
+//-----------------------------------------------------------------------------
+//
+// Public methods
+//
+//-----------------------------------------------------------------------------
+
+//-----------------------------------------------------------------------------
+// wxGStreamerMediaBackend Constructor
+//
+// Sets m_playbin to NULL signifying we havn't loaded anything yet
+//-----------------------------------------------------------------------------
 wxGStreamerMediaBackend::wxGStreamerMediaBackend()
 wxGStreamerMediaBackend::wxGStreamerMediaBackend()
+    : m_playbin(NULL),
+      m_eventHandler(NULL)
 {
 }
 
 {
 }
 
+//-----------------------------------------------------------------------------
+// wxGStreamerMediaBackend Destructor
+//
+// Stops/cleans up memory
+//
+// NB: This could trigger a critical warning but doing a SyncStateChange
+//     here is just going to slow down quitting of the app, which is bad.
+//-----------------------------------------------------------------------------
 wxGStreamerMediaBackend::~wxGStreamerMediaBackend()
 {
 wxGStreamerMediaBackend::~wxGStreamerMediaBackend()
 {
-    gst_element_set_state (m_player, GST_STATE_NULL);
-    gst_object_unref (GST_OBJECT (m_player));
-    gst_object_unref (GST_OBJECT (m_videosink));
-    gst_object_unref (GST_OBJECT (m_audiosink));
+    // Dispose of the main player and related objects
+    if(m_playbin)
+    {
+        wxASSERT( GST_IS_OBJECT(m_playbin) );
+        gst_element_set_state (m_playbin, GST_STATE_NULL);
+        gst_object_unref (GST_OBJECT (m_playbin));
+        delete m_eventHandler;
+    }
 }
 
 }
 
+//-----------------------------------------------------------------------------
+// wxGStreamerMediaBackend::CreateControl
+//
+// Initializes GStreamer and creates the wx side of our media control
+//-----------------------------------------------------------------------------
 bool wxGStreamerMediaBackend::CreateControl(wxControl* ctrl, wxWindow* parent,
                                 wxWindowID id,
                                 const wxPoint& pos,
 bool wxGStreamerMediaBackend::CreateControl(wxControl* ctrl, wxWindow* parent,
                                 wxWindowID id,
                                 const wxPoint& pos,
@@ -143,253 +966,619 @@ bool wxGStreamerMediaBackend::CreateControl(wxControl* ctrl, wxWindow* parent,
                                 const wxValidator& validator,
                                 const wxString& name)
 {
                                 const wxValidator& validator,
                                 const wxString& name)
 {
+    //
     //init gstreamer
     //init gstreamer
-    gst_init(NULL, NULL);
-
     //
     //
-    // Create window
-    // By default wxWindow(s) is created with a border -
-    // so we need to get rid of those    return Load(
+
+    //Convert arguments to unicode if enabled
+#if wxUSE_UNICODE
+    int i;
+    char **argvGST = new char*[wxTheApp->argc + 1];
+    for ( i = 0; i < wxTheApp->argc; i++ )
+    {
+#if wxUSE_UNICODE_WCHAR
+        argvGST[i] = wxStrdupA(wxConvUTF8.cWX2MB(wxTheApp->argv[i]));
+#else
+        argvGST[i] = wxStrdupA(wxTheApp->argv[i].utf8_str());
+#endif
+    }
+
+    argvGST[wxTheApp->argc] = NULL;
+
+    int argcGST = wxTheApp->argc;
+#else
+#define argcGST wxTheApp->argc
+#define argvGST wxTheApp->argv
+#endif
+
+    //Really init gstreamer
+    gboolean bInited;
+    GError* error = NULL;
+#if GST_VERSION_MAJOR > 0 || GST_VERSION_MINOR >= 10
+    bInited = gst_init_check(&argcGST, &argvGST, &error);
+#else
+    bInited = gst_init_check(&argcGST, &argvGST);
+#endif
+
+    // Cleanup arguments for unicode case
+#if wxUSE_UNICODE
+    for ( i = 0; i < argcGST; i++ )
+    {
+        free(argvGST[i]);
+    }
+
+    delete [] argvGST;
+#endif
+
+    if(!bInited)    //gst_init_check fail?
+    {
+        if(error)
+        {
+            wxLogSysError(wxT("Could not initialize GStreamer\n")
+                          wxT("Error Message:%s"),
+                          (const wxChar*) wxConvUTF8.cMB2WX(error->message)
+                         );
+            g_error_free(error);
+        }
+        else
+            wxLogSysError(wxT("Could not initialize GStreamer"));
+
+        return false;
+    }
+
     //
     //
-    // Since we don't have a child window like most other
-    // backends, we don't need wxCLIP_CHILDREN
+    // wxControl creation
     //
     //
-    if ( !
-    ctrl->wxControl::Create(parent, id, pos, size,
-                            style,  //remove borders???
-                            validator, name)
-        )
-        return false;
+    m_ctrl = wxStaticCast(ctrl, wxMediaCtrl);
 
 
-    m_player    = gst_element_factory_make ("playbin", "play");
-    m_audiosink = gst_element_factory_make ("alsasink", "audiosink");
-    m_videosink = gst_element_factory_make ("xvimagesink", "videosink");
+#ifdef __WXGTK__
+    // We handle our own GTK expose events
+    m_ctrl->m_noExpose = true;
+#endif
 
 
-    g_object_set (G_OBJECT (m_player),
-                    "video-sink", m_videosink,
-                    "audio-sink", m_audiosink,
-                    NULL);
+    if( !m_ctrl->wxControl::Create(parent, id, pos, size,
+                            style,  // TODO: remove borders???
+                            validator, name) )
+    {
+        wxFAIL_MSG(wxT("Could not create wxControl!!!"));
+        return false;
+    }
+
+#ifdef __WXGTK__
+    // Turn off double-buffering so that
+    // so it doesn't draw over the video and cause sporadic
+    // disappearances of the video
+    gtk_widget_set_double_buffered(m_ctrl->m_wxwindow, FALSE);
+#endif
 
 
-    g_signal_connect (m_player, "eos", G_CALLBACK (OnError), this);
-    g_signal_connect (m_player, "error", G_CALLBACK (OnFinish), this);
+    // don't erase the background of our control window
+    // so that resizing is a bit smoother
+    m_ctrl->SetBackgroundStyle(wxBG_STYLE_CUSTOM);
 
 
-    if ( ! GST_IS_X_OVERLAY(m_videosink) )
+    // Create our playbin object
+    m_playbin = gst_element_factory_make ("playbin", "play");
+    if (!GST_IS_ELEMENT(m_playbin))
+    {
+        if(G_IS_OBJECT(m_playbin))
+            g_object_unref(m_playbin);
+        wxLogSysError(wxT("Got an invalid playbin"));
         return false;
         return false;
+    }
 
 
-    gst_x_overlay_set_xwindow_id( GST_X_OVERLAY(m_videosink),
-#ifdef __WXGTK__
-                        GDK_WINDOW_XWINDOW(ctrl->GetHandle())
+#if GST_VERSION_MAJOR == 0 && GST_VERSION_MINOR < 10
+    // Connect the glib events/callbacks we want to our playbin
+    g_signal_connect(m_playbin, "eos",
+                     G_CALLBACK(gst_finish_callback), this);
+    g_signal_connect(m_playbin, "error",
+                     G_CALLBACK(gst_error_callback), this);
+    g_signal_connect(m_playbin, "state-change",
+                     G_CALLBACK(gst_state_change_callback), this);
 #else
 #else
-                        ctrl->GetHandle()
+    // GStreamer 0.10+ uses GstBus for this now, connect to the sync
+    // handler as well so we can set the X window id of our xoverlay
+    gst_bus_add_watch (gst_element_get_bus(m_playbin),
+                       (GstBusFunc) gst_bus_async_callback, this);
+    gst_bus_set_sync_handler(gst_element_get_bus(m_playbin),
+                             (GstBusSyncHandler) gst_bus_sync_callback, this);
+    g_signal_connect(m_playbin, "notify::stream-info",
+                     G_CALLBACK(gst_notify_stream_info_callback), this);
 #endif
 #endif
-                                  );
+
+    // Get the audio sink
+    GstElement* audiosink = gst_gconf_get_default_audio_sink();
+    if( !TryAudioSink(audiosink) )
+    {
+        // fallback to autodetection, then alsa, then oss as a stopgap
+        audiosink = gst_element_factory_make ("autoaudiosink", "audio-sink");
+        if( !TryAudioSink(audiosink) )
+        {
+            audiosink = gst_element_factory_make ("alsasink", "alsa-output");
+            if( !TryAudioSink(audiosink) )
+            {
+                audiosink = gst_element_factory_make ("osssink", "play_audio");
+                if( !TryAudioSink(audiosink) )
+                {
+                    wxLogSysError(wxT("Could not find a valid audiosink"));
+                    return false;
+                }
+            }
+        }
+    }
+
+    // Setup video sink - first try gconf, then auto, then xvimage and
+    // then finally plain ximage
+    GstElement* videosink = gst_gconf_get_default_video_sink();
+    if( !TryVideoSink(videosink) )
+    {
+        videosink = gst_element_factory_make ("autovideosink", "video-sink");
+        if( !TryVideoSink(videosink) )
+        {
+            videosink = gst_element_factory_make ("xvimagesink", "video-sink");
+            if( !TryVideoSink(videosink) )
+            {
+                // finally, do a final fallback to ximagesink
+                videosink =
+                    gst_element_factory_make ("ximagesink", "video-sink");
+                if( !TryVideoSink(videosink) )
+                {
+                    g_object_unref(audiosink);
+                    wxLogSysError(wxT("Could not find a suitable video sink"));
+                    return false;
+                }
+            }
+        }
+    }
+
+#if GST_VERSION_MAJOR == 0 && GST_VERSION_MINOR < 10
+    // Not on 0.10... called when video size changes
+    g_signal_connect(m_xoverlay, "desired-size-changed",
+                     G_CALLBACK(gst_desired_size_changed_callback), this);
+#endif
+    // Tell GStreamer which window to draw to in 0.8 - 0.10
+    // sometimes needs this too...
+    SetupXOverlay();
+
+    // Now that we know (or, rather think) our video and audio sink
+    // are valid set our playbin to use them
+    g_object_set (G_OBJECT (m_playbin),
+                  "video-sink", videosink,
+                  "audio-sink", audiosink,
+                   NULL);
+
+    m_eventHandler = new wxGStreamerMediaEventHandler(this);
     return true;
 }
 
     return true;
 }
 
-void wxGStreamerMediaBackend::OnFinish(GstElement *play, gpointer    data)
+//-----------------------------------------------------------------------------
+// wxGStreamerMediaBackend::Load (File version)
+//
+// Just calls DoLoad() with a prepended file scheme
+//-----------------------------------------------------------------------------
+bool wxGStreamerMediaBackend::Load(const wxString& fileName)
 {
 {
-    wxGStreamerMediaBackend* m_parent = (wxGStreamerMediaBackend*) data;
-
-    wxMediaEvent theEvent(wxEVT_MEDIA_STOP,
-                        m_parent->m_ctrl->GetId());
-    m_parent->m_ctrl->ProcessEvent(theEvent);
+    return DoLoad(wxString( wxT("file://") ) + fileName);
+}
 
 
-    if(theEvent.IsAllowed())
+//-----------------------------------------------------------------------------
+// wxGStreamerMediaBackend::Load (URI version)
+//
+// In the case of a file URI passes it unencoded -
+// also, as of 0.10.3 and earlier GstURI (the uri parser for gstreamer)
+// is sort of broken and only accepts uris with at least two slashes
+// after the scheme (i.e. file: == not ok, file:// == ok)
+//-----------------------------------------------------------------------------
+bool wxGStreamerMediaBackend::Load(const wxURI& location)
+{
+    if(location.GetScheme().CmpNoCase(wxT("file")) == 0)
     {
     {
-        bool bOk = m_parent->Stop();
-        wxASSERT(bOk);
+        wxString uristring = location.BuildUnescapedURI();
 
 
-        //send the event to our child
-        wxMediaEvent theEvent(wxEVT_MEDIA_FINISHED,
-                            m_parent->m_ctrl->GetId());
-        m_parent->m_ctrl->ProcessEvent(theEvent);
+        //Workaround GstURI leading "//" problem and make sure it leads
+        //with that
+        return DoLoad(wxString(wxT("file://")) +
+                      uristring.Right(uristring.length() - 5)
+                     );
     }
     }
+    else
+        return DoLoad(location.BuildURI());
 }
 
 }
 
-void wxGStreamerMediaBackend::OnError(GstElement *play,
-    GstElement *src,
-    GError     *err,
-    gchar      *debug,
-    gpointer    data)
+//-----------------------------------------------------------------------------
+// wxGStreamerMediaBackend::DoLoad
+//
+// Loads the media
+// 1) Reset member variables and set playbin back to ready state
+// 2) Check URI for validity and then tell the playbin to load it
+// 3) Set the playbin to the pause state
+//
+// NB: Even after this function is over with we probably don't have the
+// video size or duration - no amount of clever hacking is going to get
+// around that, unfortunately.
+//-----------------------------------------------------------------------------
+bool wxGStreamerMediaBackend::DoLoad(const wxString& locstring)
 {
 {
-    wxLogSysError(wxString::Format(wxT("Error in GStreamer Playback!\nError Message:%s"), wxString(err->message).c_str()));
-}
+    wxMutexLocker lock(m_asynclock); // lock state events and async callbacks
 
 
+    // Reset positions & rate
+    m_llPausedPos = 0;
+    m_dRate = 1.0;
+    m_videoSize = wxSize(0,0);
 
 
-bool wxGStreamerMediaBackend::Load(const wxString& fileName)
-{
-    return Load(
-                wxURI(
-                    wxString( wxT("file://") ) + fileName
-                     )
-               );
-}
+    // Set playbin to ready to stop the current media...
+    if( gst_element_set_state (m_playbin,
+                               GST_STATE_READY) == GST_STATE_FAILURE ||
+        !SyncStateChange(m_playbin, GST_STATE_READY))
+    {
+        wxLogSysError(wxT("wxGStreamerMediaBackend::Load - ")
+                      wxT("Could not set initial state to ready"));
+            return false;
+    }
 
 
-bool wxGStreamerMediaBackend::Load(const wxURI& location)
-{
-    Cleanup();
-    wxString locstring = location.BuildURI();
+    // free current media resources
+    gst_element_set_state (m_playbin, GST_STATE_NULL);
 
 
+    // Make sure the passed URI is valid and tell playbin to load it
+    // non-file uris are encoded
+    wxASSERT(gst_uri_protocol_is_valid("file"));
+    wxASSERT(gst_uri_is_valid(locstring.mb_str()));
 
 
-    if ( GST_STATE(m_player) > GST_STATE_READY )
-        gst_element_set_state(m_player, GST_STATE_READY);
+    g_object_set (G_OBJECT (m_playbin), "uri",
+                  (const char*)locstring.mb_str(), NULL);
 
 
-    g_object_set (G_OBJECT (m_player), "uri", locstring.c_str(), NULL);
+    // Try to pause media as gstreamer won't let us query attributes
+    // such as video size unless it is paused or playing
+    if( gst_element_set_state (m_playbin,
+                               GST_STATE_PAUSED) == GST_STATE_FAILURE ||
+        !SyncStateChange(m_playbin, GST_STATE_PAUSED))
+    {
+        return false; // no real error message needed here as this is
+                      // generic failure 99% of the time (i.e. no
+                      // source etc.) and has an error message
+    }
 
 
-    gst_x_overlay_expose(GST_X_OVERLAY(m_videosink));
 
 
-    return GST_STATE(m_player) == GST_STATE_READY;
+    NotifyMovieLoaded(); // Notify the user - all we can do for now
+    return true;
 }
 
 }
 
+
+//-----------------------------------------------------------------------------
+// wxGStreamerMediaBackend::Play
+//
+// Sets the stream to a playing state
+//
+// THREAD-UNSAFE in 0.8, maybe in 0.10 as well
+//-----------------------------------------------------------------------------
 bool wxGStreamerMediaBackend::Play()
 {
 bool wxGStreamerMediaBackend::Play()
 {
-    if (gst_element_set_state (m_player, GST_STATE_PLAYING)
-            != GST_STATE_SUCCESS)
+    if (gst_element_set_state (m_playbin,
+                               GST_STATE_PLAYING) == GST_STATE_FAILURE)
         return false;
     return true;
 }
 
         return false;
     return true;
 }
 
+//-----------------------------------------------------------------------------
+// wxGStreamerMediaBackend::Pause
+//
+// Marks where we paused and pauses the stream
+//
+// THREAD-UNSAFE in 0.8, maybe in 0.10 as well
+//-----------------------------------------------------------------------------
 bool wxGStreamerMediaBackend::Pause()
 {
 bool wxGStreamerMediaBackend::Pause()
 {
-    if (gst_element_set_state (m_player, GST_STATE_PAUSED)
-            != GST_STATE_SUCCESS)
+    m_llPausedPos = wxGStreamerMediaBackend::GetPosition();
+    if (gst_element_set_state (m_playbin,
+                               GST_STATE_PAUSED) == GST_STATE_FAILURE)
         return false;
     return true;
 }
 
         return false;
     return true;
 }
 
+//-----------------------------------------------------------------------------
+// wxGStreamerMediaBackend::Stop
+//
+// Pauses the stream and sets the position to 0. Note that this is
+// synchronous (!) pausing.
+//
+// Due to the mutex locking this is probably thread-safe actually.
+//-----------------------------------------------------------------------------
 bool wxGStreamerMediaBackend::Stop()
 {
 bool wxGStreamerMediaBackend::Stop()
 {
-    if (gst_element_set_state (m_player,
-                    GST_STATE_READY)    != GST_STATE_SUCCESS)
+    {   // begin state lock
+        wxMutexLocker lock(m_asynclock);
+        if(gst_element_set_state (m_playbin,
+                                  GST_STATE_PAUSED) == GST_STATE_FAILURE ||
+          !SyncStateChange(m_playbin, GST_STATE_PAUSED))
+        {
+            wxLogSysError(wxT("Could not set state to paused for Stop()"));
+            return false;
+        }
+    }   // end state lock
+
+    bool bSeekedOK = wxGStreamerMediaBackend::SetPosition(0);
+
+    if(!bSeekedOK)
+    {
+        wxLogSysError(wxT("Could not seek to initial position in Stop()"));
         return false;
         return false;
+    }
+
+    QueueStopEvent(); // Success
     return true;
 }
 
     return true;
 }
 
+//-----------------------------------------------------------------------------
+// wxGStreamerMediaBackend::GetState
+//
+// Gets the state of the media
+//-----------------------------------------------------------------------------
 wxMediaState wxGStreamerMediaBackend::GetState()
 {
 wxMediaState wxGStreamerMediaBackend::GetState()
 {
-    switch(GST_STATE(m_player))
+    switch(GST_STATE(m_playbin))
     {
         case GST_STATE_PLAYING:
             return wxMEDIASTATE_PLAYING;
         case GST_STATE_PAUSED:
     {
         case GST_STATE_PLAYING:
             return wxMEDIASTATE_PLAYING;
         case GST_STATE_PAUSED:
-            return wxMEDIASTATE_PAUSED;
+            if (m_llPausedPos == 0)
+                return wxMEDIASTATE_STOPPED;
+            else
+                return wxMEDIASTATE_PAUSED;
         default://case GST_STATE_READY:
             return wxMEDIASTATE_STOPPED;
     }
 }
 
         default://case GST_STATE_READY:
             return wxMEDIASTATE_STOPPED;
     }
 }
 
-bool wxGStreamerMediaBackend::SetPosition(wxLongLong where)
+//-----------------------------------------------------------------------------
+// wxGStreamerMediaBackend::GetPosition
+//
+// If paused, returns our marked position - otherwise it queries the
+// GStreamer playbin for the position and returns that
+//
+// NB:
+// NB: At least in 0.8, when you pause and seek gstreamer
+// NB: doesn't update the position sometimes, so we need to keep track of
+// NB: whether we have paused or not and keep track of the time after the
+// NB: pause and whenever the user seeks while paused
+// NB:
+//
+// THREAD-UNSAFE, at least if not paused. Requires media to be at least paused.
+//-----------------------------------------------------------------------------
+wxLongLong wxGStreamerMediaBackend::GetPosition()
 {
 {
-    return gst_element_seek (play, (GstSeekType) (GST_SEEK_METHOD_SET |
-            GST_FORMAT_TIME | GST_SEEK_FLAG_FLUSH),
-            where * GST_MSECOND );
+    if(GetState() != wxMEDIASTATE_PLAYING)
+        return m_llPausedPos;
+    else
+    {
+        gint64 pos;
+        GstFormat fmtTime = GST_FORMAT_TIME;
+
+        if (!wxGst_element_query_position(m_playbin, &fmtTime, &pos) ||
+            fmtTime != GST_FORMAT_TIME || pos == -1)
+            return 0;
+        return pos / GST_MSECOND ;
+    }
 }
 
 }
 
-wxLongLong wxGStreamerMediaBackend::GetPosition()
+//-----------------------------------------------------------------------------
+// wxGStreamerMediaBackend::SetPosition
+//
+// Sets the position of the stream
+// Note that GST_MSECOND is 1000000 (GStreamer uses nanoseconds - so
+// there is 1000000 nanoseconds in a millisecond)
+//
+// If we are paused we update the cached pause position.
+//
+// This is also an exceedingly ugly function due to the three implementations
+// (or, rather two plus one implementation without a seek function).
+//
+// This is asynchronous and thread-safe on both 0.8 and 0.10.
+//
+// NB: This fires both a stop and play event if the media was previously
+// playing... which in some ways makes sense. And yes, this makes the video
+// go all haywire at times - a gstreamer bug...
+//-----------------------------------------------------------------------------
+bool wxGStreamerMediaBackend::SetPosition(wxLongLong where)
 {
 {
-    gint64 pos;
-    GstFormat fmtTime = GST_FORMAT_TIME;
+#if GST_VERSION_MAJOR == 0 && GST_VERSION_MINOR == 8 \
+                           && GST_VERSION_MICRO == 0
+    // 0.8.0 has no gst_element_seek according to official docs!!!
+    wxLogSysError(wxT("GStreamer 0.8.0 does not have gst_element_seek")
+                  wxT(" according to official docs"));
+    return false;
+#else // != 0.8.0
+
+#   if GST_VERSION_MAJOR > 0 || GST_VERSION_MINOR >= 10
+        gst_element_seek (m_playbin, m_dRate, GST_FORMAT_TIME,
+           (GstSeekFlags)(GST_SEEK_FLAG_FLUSH | GST_SEEK_FLAG_KEY_UNIT),
+                          GST_SEEK_TYPE_SET, where.GetValue() * GST_MSECOND,
+                          GST_SEEK_TYPE_NONE, GST_CLOCK_TIME_NONE );
+#   else
+        // NB: Some gstreamer versions return false basically all the time
+        // here - even totem doesn't bother to check the return value here
+        // so I guess we'll just assume it worked -
+        // TODO: maybe check the gst error callback???
+        gst_element_seek (m_playbin, (GstSeekType) (GST_SEEK_METHOD_SET |
+            GST_FORMAT_TIME | GST_SEEK_FLAG_FLUSH),
+            where.GetValue() * GST_MSECOND );
 
 
-    if (!gst_element_query (play, GST_QUERY_POSITION, &fmtTime, &pos))
-        return 0;
-    return pos / GST_MSECOND ;
+#   endif // GST_VERSION_MAJOR > 0 || GST_VERSION_MINOR >= 10
+
+    {
+        m_llPausedPos = where;
+        return true;
+    }
+    return true;
+#endif //== 0.8.0
 }
 
 }
 
+//-----------------------------------------------------------------------------
+// wxGStreamerMediaBackend::GetDuration
+//
+// Obtains the total time of our stream
+// THREAD-UNSAFE, requires media to be paused or playing
+//-----------------------------------------------------------------------------
 wxLongLong wxGStreamerMediaBackend::GetDuration()
 {
     gint64 length;
     GstFormat fmtTime = GST_FORMAT_TIME;
 
 wxLongLong wxGStreamerMediaBackend::GetDuration()
 {
     gint64 length;
     GstFormat fmtTime = GST_FORMAT_TIME;
 
-    if(!gst_element_query(m_player, GST_QUERY_TOTAL, &fmtTime, &length))
+    if(!wxGst_element_query_duration(m_playbin, &fmtTime, &length) ||
+       fmtTime != GST_FORMAT_TIME || length == -1)
         return 0;
     return length / GST_MSECOND ;
 }
 
         return 0;
     return length / GST_MSECOND ;
 }
 
+//-----------------------------------------------------------------------------
+// wxGStreamerMediaBackend::Move
+//
+// Called when the window is moved - GStreamer takes care of this
+// for us so nothing is needed
+//-----------------------------------------------------------------------------
 void wxGStreamerMediaBackend::Move(int x, int y, int w, int h)
 {
 }
 
 void wxGStreamerMediaBackend::Move(int x, int y, int w, int h)
 {
 }
 
+//-----------------------------------------------------------------------------
+// wxGStreamerMediaBackend::GetVideoSize
+//
+// Returns our cached video size from Load/gst_notify_caps_callback
+// gst_x_overlay_get_desired_size also does this in 0.8...
+//-----------------------------------------------------------------------------
 wxSize wxGStreamerMediaBackend::GetVideoSize() const
 {
 wxSize wxGStreamerMediaBackend::GetVideoSize() const
 {
-    //TODO: check state
-    //TODO: maybe cache size
-    wxSize retSize = wxSize(0,0);
+    return m_videoSize;
+}
 
 
-    const GList *list = NULL;
-    g_object_get (G_OBJECT (m_player), "stream-info", &list, NULL);
+//-----------------------------------------------------------------------------
+// wxGStreamerMediaBackend::GetPlaybackRate
+// wxGStreamerMediaBackend::SetPlaybackRate
+//
+// Obtains/Sets the playback rate of the stream
+//
+//TODO: PlaybackRate not currently supported via playbin directly -
+//TODO: Ronald S. Bultje noted on gstreamer-devel:
+//TODO:
+//TODO: Like "play at twice normal speed"? Or "play at 25 fps and 44,1 kHz"? As
+//TODO: for the first, yes, we have elements for that, btu they"re not part of
+//TODO: playbin. You can create a bin (with a ghost pad) containing the actual
+//TODO: video/audiosink and the speed-changing element for this, and set that
+//TODO: element as video-sink or audio-sink property in playbin. The
+//TODO: audio-element is called "speed", the video-element is called "videodrop"
+//TODO: (although that appears to be deprecated in favour of "videorate", which
+//TODO: again cannot do this, so this may not work at all in the end). For
+//TODO: forcing frame/samplerates, see audioscale and videorate. Audioscale is
+//TODO: part of playbin.
+//
+// In 0.10 GStreamer has new gst_element_seek API that might
+// support this - and I've got an attempt to do so but it is untested
+// but it would appear to work...
+//-----------------------------------------------------------------------------
+double wxGStreamerMediaBackend::GetPlaybackRate()
+{
+    return m_dRate; // Could use GST_QUERY_RATE but the API doesn't seem
+                    // final on that yet and there may not be any actual
+                    // plugins that support it...
+}
 
 
-    for ( ; list != NULL; list = list->next)
+bool wxGStreamerMediaBackend::SetPlaybackRate(double dRate)
+{
+#if GST_VERSION_MAJOR > 0 || GST_VERSION_MINOR >= 10
+#if 0 // not tested enough
+    if( gst_element_seek (m_playbin, dRate, GST_FORMAT_TIME,
+                 (GstSeekFlags)(GST_SEEK_FLAG_FLUSH | GST_SEEK_FLAG_KEY_UNIT),
+                          GST_SEEK_TYPE_CUR, 0,
+                          GST_SEEK_TYPE_NONE, GST_CLOCK_TIME_NONE ) )
     {
     {
-        GObject *info = (GObject *) list->data;
-        gint type;
-        GParamSpec *pspec;
-        GEnumValue *val;
-        GstPad *pad = NULL;
-
-        g_object_get (info, "type", &type, NULL);
-        pspec = g_object_class_find_property (
-                        G_OBJECT_GET_CLASS (info), "type");
-        val = g_enum_get_value (G_PARAM_SPEC_ENUM (pspec)->enum_class, type);
-
-        if (strstr (val->value_name, "VIDEO"))
-        {
-            g_object_get (info, "object", &pad, NULL);
-            pad = (GstPad *) GST_PAD_REALIZE (pad);
-            wxAssert(pad);
-
-            GstCaps* caps = GST_PAD_CAPS (pad);
-            wxAssert(caps);
+        m_dRate = dRate;
+        return true;
+    }
+#endif
+#endif
 
 
-            const GstStructure *s;
-            s = gst_caps_get_structure (caps, 0);
-            wxAssert(s);
+    // failure
+    return false;
+}
 
 
-            gst_structure_get_int (s, "width", &retSize.x);
-            gst_structure_get_int (s, "height", &retSize.y);
+//-----------------------------------------------------------------------------
+// wxGStreamerMediaBackend::GetDownloadProgress
+//
+// Not really outwardly possible - have been suggested that one could
+// get the information from the component that "downloads"
+//-----------------------------------------------------------------------------
+wxLongLong wxGStreamerMediaBackend::GetDownloadProgress()
+{
+    return 0;
+}
 
 
-            const GValue *par;
-            par = gst_structure_get_value (s, "pixel-aspect-ratio"));
+//-----------------------------------------------------------------------------
+// wxGStreamerMediaBackend::GetDownloadTotal
+//
+// TODO: Cache this?
+// NB: The length changes every call for some reason due to
+//     GStreamer implementation issues
+// THREAD-UNSAFE, requires media to be paused or playing
+//-----------------------------------------------------------------------------
+wxLongLong wxGStreamerMediaBackend::GetDownloadTotal()
+{
+    gint64 length;
+    GstFormat fmtBytes = GST_FORMAT_BYTES;
 
 
-            if (par)
-            {
-                int num = gst_value_get_fraction_numerator (par),
-                    den = gst_value_get_fraction_denominator (par);
-
-                //TODO: maybe better fraction normalization...
-                if (num > den)
-                    retSize.x = (int) ((float) num * retSize.x / den);
-                else
-                    retSize.y = (int) ((float) den * retSize.y / num);
-            }
-        }
-    }
+    if (!wxGst_element_query_duration(m_playbin, &fmtBytes, &length) ||
+          fmtBytes != GST_FORMAT_BYTES || length == -1)
+        return 0;
+    return length;
 }
 
 }
 
-double wxGStreamerMediaBackend::GetPlaybackRate()
+//-----------------------------------------------------------------------------
+// wxGStreamerMediaBackend::SetVolume
+// wxGStreamerMediaBackend::GetVolume
+//
+// Sets/Gets the volume through the playbin object.
+// Note that this requires a relatively recent gst-plugins so we
+// check at runtime to see whether it is available or not otherwise
+// GST spits out an error on the command line
+//-----------------------------------------------------------------------------
+bool wxGStreamerMediaBackend::SetVolume(double dVolume)
 {
 {
-    //guess...
-    GstClock* theClock = gst_element_get_clock(m_player);
-    wxAssert(theClock);
-    return gst_clock_get_speed(theClock);
+    if(g_object_class_find_property(
+            G_OBJECT_GET_CLASS(G_OBJECT(m_playbin)),
+            "volume") != NULL)
+    {
+        g_object_set(G_OBJECT(m_playbin), "volume", dVolume, NULL);
+        return true;
+    }
+    else
+    {
+        wxLogTrace(wxTRACE_GStreamer,
+            wxT("SetVolume: volume prop not found - 0.8.5 of ")
+            wxT("gst-plugins probably needed"));
+    return false;
+    }
 }
 
 }
 
-bool wxGStreamerMediaBackend::SetPlaybackRate(double dRate)
+double wxGStreamerMediaBackend::GetVolume()
 {
 {
-    //guess...
-    GstClock* theClock = gst_element_get_clock(m_player);
-    wxAssert(theClock);
-    return gst_clock_change_speed(theClock, GetPlaybackRate(), dRate)==dRate;
+    double dVolume = 1.0;
+
+    if(g_object_class_find_property(
+            G_OBJECT_GET_CLASS(G_OBJECT(m_playbin)),
+            "volume") != NULL)
+    {
+        g_object_get(G_OBJECT(m_playbin), "volume", &dVolume, NULL);
+    }
+    else
+    {
+        wxLogTrace(wxTRACE_GStreamer,
+            wxT("GetVolume: volume prop not found - 0.8.5 of ")
+            wxT("gst-plugins probably needed"));
+    }
+
+    return dVolume;
 }
 
 #endif //wxUSE_GSTREAMER
 
 }
 
 #endif //wxUSE_GSTREAMER
 
-//in source file that contains stuff you don't directly use
-#include <wx/html/forcelnk.h>
-FORCE_LINK_ME(basewxmediabackends);
+// Force link into main library so this backend can be loaded
+#include "wx/html/forcelnk.h"
+FORCE_LINK_ME(basewxmediabackends)
 
 #endif //wxUSE_MEDIACTRL
 
 #endif //wxUSE_MEDIACTRL
-
-
-
-
-