this needs testing, untested parts should be reversed before release
i tested 24->32, 15->16, bgr24->rgb, bgr32->rgb (retesting them isnt a bad idea either ...)
git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@6097 b3059339-0415-0410-9bf9-f77b7e298cf2