GStreamer: refactored widget and window control.

Instead of always using xvimagesink as GStreamer backend for the
widget and window control (works only with X11), we now try to
pick a video sink that fits the current configuration.
It first tries a set of known video sinks that can work with
the Qt platform plugin in use. If none is available, it
dynamically picks a video sink available on the system that can be
used with our backend.

Even if the video sink is now picked in a smarter way, xcb is still
the only supported platform plugin. The reason is that it's the
only Unix plugin which can provide a valid native window handle.
Additional work is needed to support other plugins like wayland
or directfb.

Change-Id: I3843dea363d6a0b85a6cc1f2952783b743e48ac6
Reviewed-by: Christian Stromme <christian.stromme@theqtcompany.com>

4 files changed, 144 insertions, 32 deletions

diff --git a/src/multimedia/gsttools_headers/qgstreamervideooverlay_p.h b/src/multimedia/gsttools_headers/qgstreamervideooverlay_p.h
new file mode 100644
index 000000000..e18a1b5ca
--- /dev/null
+++ b/src/multimedia/gsttools_headers/qgstreamervideooverlay_p.h
@@ -0,0 +1,120 @@
+/****************************************************************************
+**
+** Copyright (C) 2015 The Qt Company Ltd.
+** Contact: http://www.qt.io/licensing/
+**
+** This file is part of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL21$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see http://www.qt.io/terms-conditions. For further
+** information use the contact form at http://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 or version 3 as published by the Free
+** Software Foundation and appearing in the file LICENSE.LGPLv21 and
+** LICENSE.LGPLv3 included in the packaging of this file. Please review the
+** following information to ensure the GNU Lesser General Public License
+** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** As a special exception, The Qt Company gives you certain additional
+** rights. These rights are described in The Qt Company LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QGSTREAMERVIDEOOVERLAY_P_H
+#define QGSTREAMERVIDEOOVERLAY_P_H
+
+#include <private/qgstreamerbushelper_p.h>
+#include <private/qgstreamerbufferprobe_p.h>
+#include <QtGui/qwindowdefs.h>
+#include <QtCore/qsize.h>
+
+QT_BEGIN_NAMESPACE
+
+class QGstreamerVideoOverlay
+        : public QObject
+        , public QGstreamerSyncMessageFilter
+        , public QGstreamerBusMessageFilter
+        , private QGstreamerBufferProbe
+{
+    Q_OBJECT
+    Q_INTERFACES(QGstreamerSyncMessageFilter QGstreamerBusMessageFilter)
+public:
+    explicit QGstreamerVideoOverlay(QObject *parent = 0, const QByteArray &elementName = QByteArray());
+    virtual ~QGstreamerVideoOverlay();
+
+    GstElement *videoSink() const;
+    QSize nativeVideoSize() const;
+
+    void setWindowHandle(WId id);
+    void expose();
+    void setRenderRectangle(const QRect &rect);
+
+    bool isActive() const;
+
+    Qt::AspectRatioMode aspectRatioMode() const;
+    void setAspectRatioMode(Qt::AspectRatioMode mode);
+
+    int brightness() const;
+    void setBrightness(int brightness);
+
+    int contrast() const;
+    void setContrast(int contrast);
+
+    int hue() const;
+    void setHue(int hue);
+
+    int saturation() const;
+    void setSaturation(int saturation);
+
+    bool processSyncMessage(const QGstreamerMessage &message);
+    bool processBusMessage(const QGstreamerMessage &message);
+
+Q_SIGNALS:
+    void nativeVideoSizeChanged();
+    void activeChanged();
+    void brightnessChanged(int brightness);
+    void contrastChanged(int contrast);
+    void hueChanged(int hue);
+    void saturationChanged(int saturation);
+
+private:
+    GstElement *findBestVideoSink() const;
+    void setWindowHandle_helper(WId id);
+    void updateIsActive();
+    void probeCaps(GstCaps *caps);
+    static void showPrerollFrameChanged(GObject *, GParamSpec *, QGstreamerVideoOverlay *);
+
+    GstElement *m_videoSink;
+    QSize m_nativeVideoSize;
+    bool m_isActive;
+
+    bool m_hasForceAspectRatio;
+    bool m_hasBrightness;
+    bool m_hasContrast;
+    bool m_hasHue;
+    bool m_hasSaturation;
+    bool m_hasShowPrerollFrame;
+
+    WId m_windowId;
+    Qt::AspectRatioMode m_aspectRatioMode;
+    int m_brightness;
+    int m_contrast;
+    int m_hue;
+    int m_saturation;
+};
+
+QT_END_NAMESPACE
+
+#endif // QGSTREAMERVIDEOOVERLAY_P_H
+
diff --git a/src/multimedia/gsttools_headers/qgstreamervideowidget_p.h b/src/multimedia/gsttools_headers/qgstreamervideowidget_p.h
index 32a143c07..4526a8ac9 100644
--- a/src/multimedia/gsttools_headers/qgstreamervideowidget_p.h
+++ b/src/multimedia/gsttools_headers/qgstreamervideowidget_p.h
@@ -38,6 +38,7 @@
 
 #include "qgstreamervideorendererinterface_p.h"
 #include <private/qgstreamerbushelper_p.h>
+#include <private/qgstreamervideooverlay_p.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -52,13 +53,15 @@ class QGstreamerVideoWidgetControl
     Q_OBJECT
     Q_INTERFACES(QGstreamerVideoRendererInterface QGstreamerSyncMessageFilter QGstreamerBusMessageFilter)
 public:
-    QGstreamerVideoWidgetControl(QObject *parent = 0);
+    explicit QGstreamerVideoWidgetControl(QObject *parent = 0, const QByteArray &elementName = QByteArray());
     virtual ~QGstreamerVideoWidgetControl();
 
     GstElement *videoSink();
 
     QWidget *videoWidget();
 
+    void stopRenderer();
+
     Qt::AspectRatioMode aspectRatioMode() const;
     void setAspectRatioMode(Qt::AspectRatioMode mode);
 
@@ -77,27 +80,27 @@ public:
     int saturation() const;
     void setSaturation(int saturation);
 
-    void setOverlay();
-
     bool eventFilter(QObject *object, QEvent *event);
-    bool processSyncMessage(const QGstreamerMessage &message);
-    bool processBusMessage(const QGstreamerMessage &message);
-
-public slots:
-    void updateNativeVideoSize();
 
 signals:
     void sinkChanged();
     void readyChanged(bool);
 
+private Q_SLOTS:
+    void onOverlayActiveChanged();
+    void onNativeVideoSizeChanged();
+
 private:
     void createVideoWidget();
-    void windowExposed();
+    void updateWidgetAttributes();
+
+    bool processSyncMessage(const QGstreamerMessage &message);
+    bool processBusMessage(const QGstreamerMessage &message);
 
-    GstElement *m_videoSink;
+    QGstreamerVideoOverlay m_videoOverlay;
     QGstreamerVideoWidget *m_widget;
+    bool m_stopped;
     WId m_windowId;
-    Qt::AspectRatioMode m_aspectRatioMode;
     bool m_fullScreen;
 };
 
diff --git a/src/multimedia/gsttools_headers/qgstreamervideowindow_p.h b/src/multimedia/gsttools_headers/qgstreamervideowindow_p.h
index 5111fc884..8884aa2c0 100644
--- a/src/multimedia/gsttools_headers/qgstreamervideowindow_p.h
+++ b/src/multimedia/gsttools_headers/qgstreamervideowindow_p.h
@@ -38,23 +38,22 @@
 
 #include "qgstreamervideorendererinterface_p.h"
 #include <private/qgstreamerbushelper_p.h>
-#include <private/qgstreamerbufferprobe_p.h>
+#include <private/qgstreamervideooverlay_p.h>
 #include <QtGui/qcolor.h>
 
 QT_BEGIN_NAMESPACE
 class QAbstractVideoSurface;
 
-class QGstreamerVideoWindow : public QVideoWindowControl,
+class QGstreamerVideoWindow :
+        public QVideoWindowControl,
         public QGstreamerVideoRendererInterface,
         public QGstreamerSyncMessageFilter,
-        private QGstreamerBufferProbe
+        public QGstreamerBusMessageFilter
 {
     Q_OBJECT
-    Q_INTERFACES(QGstreamerVideoRendererInterface QGstreamerSyncMessageFilter)
-    Q_PROPERTY(QColor colorKey READ colorKey WRITE setColorKey)
-    Q_PROPERTY(bool autopaintColorKey READ autopaintColorKey WRITE setAutopaintColorKey)
+    Q_INTERFACES(QGstreamerVideoRendererInterface QGstreamerSyncMessageFilter QGstreamerBusMessageFilter)
 public:
-    QGstreamerVideoWindow(QObject *parent = 0, const char *elementName = 0);
+    explicit QGstreamerVideoWindow(QObject *parent = 0, const QByteArray &elementName = QByteArray());
     ~QGstreamerVideoWindow();
 
     WId winId() const;
@@ -71,12 +70,6 @@ public:
     Qt::AspectRatioMode aspectRatioMode() const;
     void setAspectRatioMode(Qt::AspectRatioMode mode);
 
-    QColor colorKey() const;
-    void setColorKey(const QColor &);
-
-    bool autopaintColorKey() const;
-    void setAutopaintColorKey(bool);
-
     void repaint();
 
     int brightness() const;
@@ -96,24 +89,18 @@ public:
     GstElement *videoSink();
 
     bool processSyncMessage(const QGstreamerMessage &message);
+    bool processBusMessage(const QGstreamerMessage &message);
     bool isReady() const { return m_windowId != 0; }
 
 signals:
     void sinkChanged();
     void readyChanged(bool);
 
-private slots:
-    void updateNativeVideoSize(const QSize &size);
-
 private:
-    void probeCaps(GstCaps *caps);
-
-    GstElement *m_videoSink;
+    QGstreamerVideoOverlay m_videoOverlay;
     WId m_windowId;
-    Qt::AspectRatioMode m_aspectRatioMode;
     QRect m_displayRect;
     bool m_fullScreen;
-    QSize m_nativeSize;
     mutable QColor m_colorKey;
 };
 
diff --git a/src/multimedia/gsttools_headers/qgstutils_p.h b/src/multimedia/gsttools_headers/qgstutils_p.h
index 78b9db3df..31fb85847 100644
--- a/src/multimedia/gsttools_headers/qgstutils_p.h
+++ b/src/multimedia/gsttools_headers/qgstutils_p.h
@@ -61,11 +61,13 @@
 # define QT_GSTREAMER_CAMERABIN_ELEMENT_NAME "camerabin"
 # define QT_GSTREAMER_COLORCONVERSION_ELEMENT_NAME "videoconvert"
 # define QT_GSTREAMER_RAW_AUDIO_MIME "audio/x-raw"
+# define QT_GSTREAMER_VIDEOOVERLAY_INTERFACE_NAME "GstVideoOverlay"
 #else
 # define QT_GSTREAMER_PLAYBIN_ELEMENT_NAME "playbin2"
 # define QT_GSTREAMER_CAMERABIN_ELEMENT_NAME "camerabin2"
 # define QT_GSTREAMER_COLORCONVERSION_ELEMENT_NAME "ffmpegcolorspace"
 # define QT_GSTREAMER_RAW_AUDIO_MIME "audio/x-raw-int"
+# define QT_GSTREAMER_VIDEOOVERLAY_INTERFACE_NAME "GstXOverlay"
 #endif
 
 QT_BEGIN_NAMESPACE