Multi-track video files
For most video files, audio and subtile are encoded into the video and hard to remove or replace. Unlike most video files, some video files can include several audio tracks and subtitle tracks which are seperated from video tracks, such video files are multi-track video files. When playing a multi-track video with a media player like KMPlayer, VLC Media Player, etc, user can select any audio track or subtitle track they want. It's good for users who want to watch a video in native language and subtitle. The most common used multi-track video files are .mkv files. Some .ogm and .ogv video files can also be multi-track video files.
Convert multi-track video files with Any DVD Converter
Any DVD Converter offers options to choose audio track and subtitle track for multi-track video files. Unfold "Audio Options" in right panel of Any DVD Converter, at the bottom you can find "Audio Track" and "Subtilte" option. In most cases, these two options will be grey out. However, once the added video is a multi-track video file, you will see at least one of them are settable. See the picture below.
The added video file is a .ogm file and the picture above indicates that the OGM file is a multi-track video file with 3 audio tracks. As to subtile, it could be no subtitle track or the subtitle is encoded into the video. Subtitle encoded into video is also called hard subtitle while in the other case it's called soft subtitle.
By specifying audio track number or subtile track number, Any DVD Converter easily converts multi-track video files according to your need.
Something about MKV, OGM and OGV
MKV is the most common multi-track video file formats. It's the Matroska video type with subtitle and audio. Matroska is a multimedia container, it is an open standard free container format, a file format that can hold an unlimited number of video, audio, picture or subtitle tracks inside a single file. It is intended to serve as a universal format for storing common multimedia content, like movies or TV shows. Matroska is similar in conception to other containers like AVI, MP4 or ASF, but is entirely open in specification, with implementations consisting mostly of open source software. The most common use of .MKV files is to store HD video files.
As to OGM and OGV file formats, in 2002 the lack of formal video support in Ogg resulted in the creation of the "OGM" file format, a hack on Ogg which allowed the embedding of video from the Microsoft DirectShow framework into an Ogg-based wrapper. OGM was initially supported only by closed source windows-only tools but the code base was subsequently opened. Later, Video (and subtitle) support were formally specified for Ogg but in a manner incompatible with OGM. Independently, the Matroska container format reached maturity and provided another alternative for people interested in combining Vorbis audio and arbitrary video codecs. As a result OGM is no longer supported or developed and is formally discouraged by Xiph.org. Today video in Ogg is found with the .ogv file extension which is formally specified and officially supported.
Remove audio and subtitle from MKV multi-track video files
If you just want to remove certain audio track or subtitle track from MKV and don't want to convert it to other video formats, you can achieve that easily with a free tool named MKVTOOLNIX. You can downlaod it from here. Or you can simply use this tool to check how many audio tracks and subtitle tracks in your multi-track video files.
