Implement image transforms
Should really just throw out 90% of the old "upstream" code and decode straight to a QImage. Would improve the performance and significantly slim down the codebase.
Code stolen from myself: https://invent.kde.org/sandsmark/qt-ffmpeg-imageplugin/-/blob/master/ffmpegimageplugin.cpp#L498-523
Edited by Martin Tobias Holmedahl Sandsmark