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. By default the splitter will register for all media formats that have been tested and found working at least partially. This currently includes (but is not limited to) MKV/WebM, AVI, MP4/MOV, TS/M2TS/MPG, FLV, OGG, BluRay (.bdmv and .mpls).

However, some other splitters register in a “bad” way and force all players to use them. The Haali Media Splitter is one of those, and to give priority to the LAV Splitter you have to either uninstall Haali or rename its .ax file at least temporarily. The Audio and Video Decoder will register with a relatively high merit, which should make it the preferred decoder by default. Most players offer a way to choose the preferred decoder however.

LAV Splitter offers different ways to pre-select streams when opening a file. The selection of video streams is not configurable, and LAV Splitter will quite simply pick the one with the best quality. Audio stream selection offers some flexibility, specifically you can configure your preferred languages. The language configuration is straight forward. Just enter a list of 3-letter language codes (ISO 639-2), separated by comma or space. LAV Filters (aka LAVFSplitter) is a media splitter/decoder that uses libavformat to play all sorts of your media files.