Due to its multi-threaded architecture, it allows you to avoid the extra weight of the QuickTime Player and it works fast and smooth.
You can only play file formats supported by QuickTime using WMP; other DirectShow-based media players are not supported.
The file formats supported by this QuickTime filter are MOV, MP4, M4V, AMR, DV, 3GP, 3G2, M4A, animated GIF and animated FLC.
River Past QuickTime DirectShow Filter runs on 32-bit and 64-bit Windows XP and Vista with Windows Media Player 9 and later installed.
This filter makes Windows Media Player an even better choice than the QuickTime Player because it uses QuickTime codecs directly and it is faster than the QuickTime Player itself.