commit 83026d306daecdeb8743f5a7d3bfcc752555c86e
Author: Tasuku Suzuki <tasuku.suzuki@qt.io>
Date:   Wed Dec 14 23:00:37 2016 +0900

    return better images in metadata in gstreamer
    
    cover art image uses "preview image". But "image" is better for
    that. "preview image" will be used for thumbnail image.
    
    Change-Id: Ic01f878f146b0369eb84e6b153fa68fbc6c54e57

diff --git a/src/plugins/gstreamer/mediaplayer/qgstreamermetadataprovider.cpp b/src/plugins/gstreamer/mediaplayer/qgstreamermetadataprovider.cpp
index 01103d65..b9e29245 100644
--- a/src/plugins/gstreamer/mediaplayer/qgstreamermetadataprovider.cpp
+++ b/src/plugins/gstreamer/mediaplayer/qgstreamermetadataprovider.cpp
@@ -93,7 +93,8 @@ static const QGstreamerMetaDataKeyLookup *qt_gstreamerMetaDataKeys()
 
         //metadataKeys->insert(0, QMediaMetaData::CoverArtUrlSmall);
         //metadataKeys->insert(0, QMediaMetaData::CoverArtUrlLarge);
-        metadataKeys->insert(GST_TAG_PREVIEW_IMAGE, QMediaMetaData::CoverArtImage);
+        metadataKeys->insert(GST_TAG_PREVIEW_IMAGE, QMediaMetaData::ThumbnailImage);
+        metadataKeys->insert(GST_TAG_IMAGE, QMediaMetaData::CoverArtImage);
 
         // Image/Video
         metadataKeys->insert("resolution", QMediaMetaData::Resolution);