Video scaling at Qt Browser

[vpforqt]

In our software stack,ealier video scaling in browser was done by HW.
Due to cost factors,HW DSP is removed hence software scaling is required.

Browser uses QT moblity API which in turn receives video frames from Gstreamer.
Can we do the video scaling (convert the frames to images and scale) and then render on WebKit or Qt Mobility side?

As per our analysis below patches seems to be doing the same thing but they are in Qt 5.2 ,we are running on 4.7.1.
http://code.qt.io/cgit/qt/qtwebkit.git/diff/Source/WebCore/platform/graphics/qt/MediaPlayerPrivateQt.h?h=old/5.2&id=8995b83bcbfbb68245f779b64e5517627c6cc6ea
http://code.qt.io/cgit/qt/qtwebkit.git/diff/Source/WebCore/platform/graphics/qt/MediaPlayerPrivateQt.cpp?h=old/5.2&id=8995b83bcbfbb68245f779b64e5517627c6cc6ea

Can someone first please confirm if this patch can solve the issue?
If yes, then Upgrading QT is the only solution or can we apply these which means they should be backward compatible.
If No, can someone point the patch or way to do this scaling ?