tdf#145735 qt avmedia: Return video resolution for preferred win size

In `QtPlayer::getPreferredPlayerWindowSize`, retrieve the
video resolution from the meta data and return that for the
preferred window size if available, instead of always returning
an empty rect.

For the sample presentation referenced in tdf#145735,
the size retrieved this way also matches what
`GtkPlayer::getPreferredPlayerWindowSize` returns
(720x400).

As mentioned in

commit 441d8ed9be0e7f831b455a69b8688dcb79a8bc00
Author: Michael Weghorn <m.weghorn@posteo.de>
Date:   Mon May 20 16:25:09 2024 +0200

tdf#145735 avmedia qt: Use QtMultimedia for Qt 6 media playback

, the behaviour without this was:

> * In non-presentation mode, the placeholder
>   shown until the video gets started using the controls
>   in the sidebar is just an "audio icon", not a frame
>   from the actual video. (This might be related to the
>   fact that `QtPlayer::createFrameGrabber` currently
>   returns an empty reference.)

With this in place, the placeholder is now a different
icon, a "video icon" (but still not a frame from the actual
video).

Change-Id: I295abe6b7973fece3fcaf9a38af2602cb08610a7
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/168013
Tested-by: Jenkins
Reviewed-by: Michael Weghorn <m.weghorn@posteo.de>

1 files changed, 11 insertions, 2 deletions

diff --git a/avmedia/source/qt6/QtPlayer.cxx b/avmedia/source/qt6/QtPlayer.cxx
index 1ad675f37d5c..5f75394ff1a3 100644
--- a/avmedia/source/qt6/QtPlayer.cxx
+++ b/avmedia/source/qt6/QtPlayer.cxx
@@ -11,6 +11,7 @@
 
 #include <QtCore/QUrl>
 #include <QtMultimedia/QAudioOutput>
+#include <QtMultimedia/QMediaMetaData>
 #include <QtMultimediaWidgets/QVideoWidget>
 #include <QtWidgets/QLayout>
 
@@ -178,8 +179,16 @@ awt::Size SAL_CALL QtPlayer::getPreferredPlayerWindowSize()
 {
     osl::MutexGuard aGuard(m_aMutex);
 
-    awt::Size aSize(0, 0);
-    return aSize;
+    assert(m_xMediaPlayer);
+    const QMediaMetaData aMetaData = m_xMediaPlayer->metaData();
+    const QVariant aResolutionVariant = aMetaData.value(QMediaMetaData::Resolution);
+    if (aResolutionVariant.canConvert<QSize>())
+    {
+        const QSize aResolution = aResolutionVariant.value<QSize>();
+        return awt::Size(aResolution.width(), aResolution.height());
+    }
+
+    return awt::Size(0, 0);
 }
 
 uno::Reference<::media::XPlayerWindow>