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, 37 insertions, 229 deletions

diff --git a/src/gsttools/qgstreamervideowindow.cpp b/src/gsttools/qgstreamervideowindow.cpp
index ee25acc48..befac0dda 100644
--- a/src/gsttools/qgstreamervideowindow.cpp
+++ b/src/gsttools/qgstreamervideowindow.cpp
@@ -35,52 +35,33 @@
 #include <private/qgstutils_p.h>
 
 #include <QtCore/qdebug.h>
-#include <QtGui/qguiapplication.h>
 
-#include <gst/gst.h>
-
-#if !GST_CHECK_VERSION(1,0,0)
-#include <gst/interfaces/xoverlay.h>
-#include <gst/interfaces/propertyprobe.h>
-#else
-#include <gst/video/videooverlay.h>
-#endif
-
-
-QGstreamerVideoWindow::QGstreamerVideoWindow(QObject *parent, const char *elementName)
+QGstreamerVideoWindow::QGstreamerVideoWindow(QObject *parent, const QByteArray &elementName)
     : QVideoWindowControl(parent)
-    , QGstreamerBufferProbe(QGstreamerBufferProbe::ProbeCaps)
-    , m_videoSink(0)
+    , m_videoOverlay(this, !elementName.isEmpty() ? elementName : qgetenv("QT_GSTREAMER_WINDOW_VIDEOSINK"))
     , m_windowId(0)
-    , m_aspectRatioMode(Qt::KeepAspectRatio)
     , m_fullScreen(false)
     , m_colorKey(QColor::Invalid)
 {
-    if (elementName) {
-        m_videoSink = gst_element_factory_make(elementName, NULL);
-    } else if (QGuiApplication::platformName().compare(QLatin1String("xcb"), Qt::CaseInsensitive) == 0) {
-        // We need a native X window handle to be able to use xvimagesink.
-        // Bail out if Qt is not using xcb (the control will then be ignored by the plugin)
-        m_videoSink = gst_element_factory_make("xvimagesink", NULL);
-    }
-
-    if (m_videoSink) {
-        qt_gst_object_ref_sink(GST_OBJECT(m_videoSink)); //Take ownership
-
-        GstPad *pad = gst_element_get_static_pad(m_videoSink, "sink");
-        addProbeToPad(pad);
-        gst_object_unref(GST_OBJECT(pad));
-    }
+    connect(&m_videoOverlay, &QGstreamerVideoOverlay::nativeVideoSizeChanged,
+            this, &QGstreamerVideoWindow::nativeSizeChanged);
+    connect(&m_videoOverlay, &QGstreamerVideoOverlay::brightnessChanged,
+            this, &QGstreamerVideoWindow::brightnessChanged);
+    connect(&m_videoOverlay, &QGstreamerVideoOverlay::contrastChanged,
+            this, &QGstreamerVideoWindow::contrastChanged);
+    connect(&m_videoOverlay, &QGstreamerVideoOverlay::hueChanged,
+            this, &QGstreamerVideoWindow::hueChanged);
+    connect(&m_videoOverlay, &QGstreamerVideoOverlay::saturationChanged,
+            this, &QGstreamerVideoWindow::saturationChanged);
 }
 
 QGstreamerVideoWindow::~QGstreamerVideoWindow()
 {
-    if (m_videoSink) {
-        GstPad *pad = gst_element_get_static_pad(m_videoSink,"sink");
-        removeProbeFromPad(pad);
-        gst_object_unref(GST_OBJECT(pad));
-        gst_object_unref(GST_OBJECT(m_videoSink));
-    }
+}
+
+GstElement *QGstreamerVideoWindow::videoSink()
+{
+    return m_videoOverlay.videoSink();
 }
 
 WId QGstreamerVideoWindow::winId() const
@@ -94,17 +75,8 @@ void QGstreamerVideoWindow::setWinId(WId id)
         return;
 
     WId oldId = m_windowId;
+    m_videoOverlay.setWindowHandle(m_windowId = id);
 
-    m_windowId = id;
-#if GST_CHECK_VERSION(1,0,0)
-    if (m_videoSink && GST_IS_VIDEO_OVERLAY(m_videoSink)) {
-        gst_video_overlay_set_window_handle(GST_VIDEO_OVERLAY(m_videoSink), m_windowId);
-    }
-#else
-    if (m_videoSink && GST_IS_X_OVERLAY(m_videoSink)) {
-        gst_x_overlay_set_xwindow_id(GST_X_OVERLAY(m_videoSink), m_windowId);
-    }
-#endif
     if (!oldId)
         emit readyChanged(true);
 
@@ -114,28 +86,12 @@ void QGstreamerVideoWindow::setWinId(WId id)
 
 bool QGstreamerVideoWindow::processSyncMessage(const QGstreamerMessage &message)
 {
-    GstMessage* gm = message.rawMessage();
-#if GST_CHECK_VERSION(1,0,0)
-    const GstStructure *s = gst_message_get_structure(gm);
-    if ((GST_MESSAGE_TYPE(gm) == GST_MESSAGE_ELEMENT) &&
-            gst_structure_has_name(s, "prepare-window-handle") &&
-            m_videoSink && GST_IS_VIDEO_OVERLAY(m_videoSink)) {
-
-        gst_video_overlay_set_window_handle(GST_VIDEO_OVERLAY(m_videoSink), m_windowId);
-
-        return true;
-    }
-#else
-    if ((GST_MESSAGE_TYPE(gm) == GST_MESSAGE_ELEMENT) &&
-            gst_structure_has_name(gm->structure, "prepare-xwindow-id") &&
-            m_videoSink && GST_IS_X_OVERLAY(m_videoSink)) {
-
-        gst_x_overlay_set_xwindow_id(GST_X_OVERLAY(m_videoSink), m_windowId);
+    return m_videoOverlay.processSyncMessage(message);
+}
 
-        return true;
-    }
-#endif
-    return false;
+bool QGstreamerVideoWindow::processBusMessage(const QGstreamerMessage &message)
+{
+    return m_videoOverlay.processBusMessage(message);
 }
 
 QRect QGstreamerVideoWindow::displayRect() const
@@ -145,188 +101,63 @@ QRect QGstreamerVideoWindow::displayRect() const
 
 void QGstreamerVideoWindow::setDisplayRect(const QRect &rect)
 {
-    m_displayRect = rect;
-#if GST_CHECK_VERSION(1,0,0)
-    if (m_videoSink && GST_IS_VIDEO_OVERLAY(m_videoSink)) {
-        if (m_displayRect.isEmpty())
-            gst_video_overlay_set_render_rectangle(GST_VIDEO_OVERLAY(m_videoSink), -1, -1, -1, -1);
-        else
-            gst_video_overlay_set_render_rectangle(GST_VIDEO_OVERLAY(m_videoSink),
-                                               m_displayRect.x(),
-                                               m_displayRect.y(),
-                                               m_displayRect.width(),
-                                               m_displayRect.height());
-        repaint();
-    }
-#else
-    if (m_videoSink && GST_IS_X_OVERLAY(m_videoSink)) {
-#if GST_VERSION_MICRO >= 29
-        if (m_displayRect.isEmpty())
-            gst_x_overlay_set_render_rectangle(GST_X_OVERLAY(m_videoSink), -1, -1, -1, -1);
-        else
-            gst_x_overlay_set_render_rectangle(GST_X_OVERLAY(m_videoSink),
-                                               m_displayRect.x(),
-                                               m_displayRect.y(),
-                                               m_displayRect.width(),
-                                               m_displayRect.height());
-        repaint();
-#endif
-    }
-#endif
+    m_videoOverlay.setRenderRectangle(m_displayRect = rect);
+    repaint();
 }
 
 Qt::AspectRatioMode QGstreamerVideoWindow::aspectRatioMode() const
 {
-    return m_aspectRatioMode;
+    return m_videoOverlay.aspectRatioMode();
 }
 
 void QGstreamerVideoWindow::setAspectRatioMode(Qt::AspectRatioMode mode)
 {
-    m_aspectRatioMode = mode;
-
-    if (m_videoSink) {
-        g_object_set(G_OBJECT(m_videoSink),
-                     "force-aspect-ratio",
-                     (m_aspectRatioMode == Qt::KeepAspectRatio),
-                     (const char*)NULL);
-    }
+    m_videoOverlay.setAspectRatioMode(mode);
 }
 
 void QGstreamerVideoWindow::repaint()
 {
-#if GST_CHECK_VERSION(1,0,0)
-    if (m_videoSink && GST_IS_VIDEO_OVERLAY(m_videoSink)) {
-        //don't call gst_x_overlay_expose if the sink is in null state
-        GstState state = GST_STATE_NULL;
-        GstStateChangeReturn res = gst_element_get_state(m_videoSink, &state, NULL, 1000000);
-        if (res != GST_STATE_CHANGE_FAILURE && state != GST_STATE_NULL) {
-            gst_video_overlay_expose(GST_VIDEO_OVERLAY(m_videoSink));
-        }
-    }
-#else
-    if (m_videoSink && GST_IS_X_OVERLAY(m_videoSink)) {
-        //don't call gst_x_overlay_expose if the sink is in null state
-        GstState state = GST_STATE_NULL;
-        GstStateChangeReturn res = gst_element_get_state(m_videoSink, &state, NULL, 1000000);
-        if (res != GST_STATE_CHANGE_FAILURE && state != GST_STATE_NULL) {
-            gst_x_overlay_expose(GST_X_OVERLAY(m_videoSink));
-        }
-    }
-#endif
-}
-
-QColor QGstreamerVideoWindow::colorKey() const
-{
-    if (!m_colorKey.isValid()) {
-        gint colorkey = 0;
-        if (m_videoSink && g_object_class_find_property(G_OBJECT_GET_CLASS(m_videoSink), "colorkey"))
-            g_object_get(G_OBJECT(m_videoSink), "colorkey", &colorkey, NULL);
-
-        if (colorkey > 0)
-            m_colorKey.setRgb(colorkey);
-    }
-
-    return m_colorKey;
-}
-
-void QGstreamerVideoWindow::setColorKey(const QColor &color)
-{
-    m_colorKey = color;
-
-    if (m_videoSink && g_object_class_find_property(G_OBJECT_GET_CLASS(m_videoSink), "colorkey"))
-        g_object_set(G_OBJECT(m_videoSink), "colorkey", color.rgba(), NULL);
-}
-
-bool QGstreamerVideoWindow::autopaintColorKey() const
-{
-    bool enabled = true;
-
-    if (m_videoSink && g_object_class_find_property(G_OBJECT_GET_CLASS(m_videoSink), "autopaint-colorkey"))
-        g_object_get(G_OBJECT(m_videoSink), "autopaint-colorkey", &enabled, NULL);
-
-    return enabled;
-}
-
-void QGstreamerVideoWindow::setAutopaintColorKey(bool enabled)
-{
-    if (m_videoSink && g_object_class_find_property(G_OBJECT_GET_CLASS(m_videoSink), "autopaint-colorkey"))
-        g_object_set(G_OBJECT(m_videoSink), "autopaint-colorkey", enabled, NULL);
+    m_videoOverlay.expose();
 }
 
 int QGstreamerVideoWindow::brightness() const
 {
-    int brightness = 0;
-
-    if (m_videoSink && g_object_class_find_property(G_OBJECT_GET_CLASS(m_videoSink), "brightness"))
-        g_object_get(G_OBJECT(m_videoSink), "brightness", &brightness, NULL);
-
-    return brightness / 10;
+    return m_videoOverlay.brightness();
 }
 
 void QGstreamerVideoWindow::setBrightness(int brightness)
 {
-    if (m_videoSink && g_object_class_find_property(G_OBJECT_GET_CLASS(m_videoSink), "brightness")) {
-        g_object_set(G_OBJECT(m_videoSink), "brightness", brightness * 10, NULL);
-
-        emit brightnessChanged(brightness);
-    }
+    m_videoOverlay.setBrightness(brightness);
 }
 
 int QGstreamerVideoWindow::contrast() const
 {
-    int contrast = 0;
-
-    if (m_videoSink && g_object_class_find_property(G_OBJECT_GET_CLASS(m_videoSink), "contrast"))
-        g_object_get(G_OBJECT(m_videoSink), "contrast", &contrast, NULL);
-
-    return contrast / 10;
+    return m_videoOverlay.contrast();
 }
 
 void QGstreamerVideoWindow::setContrast(int contrast)
 {
-    if (m_videoSink && g_object_class_find_property(G_OBJECT_GET_CLASS(m_videoSink), "contrast")) {
-        g_object_set(G_OBJECT(m_videoSink), "contrast", contrast * 10, NULL);
-
-        emit contrastChanged(contrast);
-    }
+    m_videoOverlay.setContrast(contrast);
 }
 
 int QGstreamerVideoWindow::hue() const
 {
-    int hue = 0;
-
-    if (m_videoSink && g_object_class_find_property(G_OBJECT_GET_CLASS(m_videoSink), "hue"))
-        g_object_get(G_OBJECT(m_videoSink), "hue", &hue, NULL);
-
-    return hue / 10;
+    return m_videoOverlay.hue();
 }
 
 void QGstreamerVideoWindow::setHue(int hue)
 {
-    if (m_videoSink && g_object_class_find_property(G_OBJECT_GET_CLASS(m_videoSink), "hue")) {
-        g_object_set(G_OBJECT(m_videoSink), "hue", hue * 10, NULL);
-
-        emit hueChanged(hue);
-    }
+    m_videoOverlay.setHue(hue);
 }
 
 int QGstreamerVideoWindow::saturation() const
 {
-    int saturation = 0;
-
-    if (m_videoSink && g_object_class_find_property(G_OBJECT_GET_CLASS(m_videoSink), "saturation"))
-        g_object_get(G_OBJECT(m_videoSink), "saturation", &saturation, NULL);
-
-    return saturation / 10;
+    return m_videoOverlay.saturation();
 }
 
 void QGstreamerVideoWindow::setSaturation(int saturation)
 {
-    if (m_videoSink && g_object_class_find_property(G_OBJECT_GET_CLASS(m_videoSink), "saturation")) {
-        g_object_set(G_OBJECT(m_videoSink), "saturation", saturation * 10, NULL);
-
-        emit saturationChanged(saturation);
-    }
+    m_videoOverlay.setSaturation(saturation);
 }
 
 bool QGstreamerVideoWindow::isFullScreen() const
@@ -341,28 +172,5 @@ void QGstreamerVideoWindow::setFullScreen(bool fullScreen)
 
 QSize QGstreamerVideoWindow::nativeSize() const
 {
-    return m_nativeSize;
-}
-
-void QGstreamerVideoWindow::probeCaps(GstCaps *caps)
-{
-    QSize resolution = QGstUtils::capsCorrectedResolution(caps);
-    QMetaObject::invokeMethod(
-                this,
-                "updateNativeVideoSize",
-                Qt::QueuedConnection,
-                Q_ARG(QSize, resolution));
-}
-
-void QGstreamerVideoWindow::updateNativeVideoSize(const QSize &size)
-{
-    if (m_nativeSize != size) {
-        m_nativeSize = size;
-        emit nativeSizeChanged();
-    }
-}
-
-GstElement *QGstreamerVideoWindow::videoSink()
-{
-    return m_videoSink;
+    return m_videoOverlay.nativeVideoSize();
 }