LAV Filters (formerly LAVFSplitter)

LAV Filters (aka LAVFSplitter) is a multi-format media splitter/decoder that uses libavformat (the demuxing library from ffmpeg) to demux all sorts of media files. 

MKV/WebM, AVI, MP4/MOV, MPEG-TS, FLV, OGG are tested and will be registered for.
Other formats can be tested using GraphStudio. H264, VC-1, MPEG4-ASP (Divx/Xvid), VP8 have been tested and are working well. DTS, AC3, TrueHD, MP3, Vorbis have been tested. Subtitle Support. Stream Switching.

http://www.videohelp.com/tools/LAV-Filters

madVR (high quality video renderer)

madVR is a high quality video renderer (GPU assisted) that can be used with any media player which supports madVR; just select madVR as the preferred renderer in the media player's settings.

http://www.free-codecs.com/download/madVR.htm