LAV Filters are a set of DirectShow filters based on the libavformat and libavcodec libraries from the ffmpeg project, which will allow you to play virtually any format in a DirectShow player.

The first part is the LAV Splitter, the first DirectShow source/splitter that leverages the full power of the avformat ffmpeg library to identify and demux media files. Due to it using avformat, it can support all important (and unimportant) media formats, even though only the main stream formats are currently officially supported.

The second part of LAV Filters is the Audio Decoder. Roughly modeled after the Gabest MpaDec Filter, its key design is to retain the maximum audio quality, without compromise. Its using a slightly modified ffmpeg library for decoding the audio, which allows it to get the untouched audio from the decoder, and sends it untouched to the audio renderer.