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>

1 files changed, 120 insertions, 0 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
+