What is Mp4 File Format?
Mp4 File Format is the short form of MPEG-4 File Format, which is generally used to contain MPEG-4 media using the ISO Base Media File Format. It includes MPEG-4 audio and video as well as MPEG-4 presentations. It becomes a specific structures of that document or presentation, when you store a complete or partial presentation in an MP4 file.
MPEG-4 BIFS describes a scene language for the scenes of the MPEG-4 presentation. In these scenes, media object are placed. These media object includes audio, video, or entire sub-scenes. The object descriptor describes each and every objects. The streams that make up that object are also described by object descriptor. The initial object descriptor (IOD) describes the entire scene. The movie atom of the MP4 file stores the entire scene in a special box. The scene and the object descriptor can be used and stored in tracks like, a scene track and an object descriptor track. To present any full MPEG-4 presentation this IOD and these two tracks are required.
The stream descriptor describes the each and every streams. When the scene become complete than it delivered as part of the object descriptor stream. The stream descriptor also manage that files, which only contains media streams. These type of elementary stream descriptor can be stored in the media stream themselves. It is stored in the descriptive track structures in MP4 files. MP4 is a global multimedia standard, delivering professional-quality audio and video streams over a wide range of bandwidths , from cell phone to broadband and beyond. MP4 is used to compress video. The extension of the MP4 file format includes following.
- .mp4:- it is used for audio, video and advanced content files. It is an official extension.
- .m4a:- it shows audio-only. It can be renamed to *.mp4 easily.
- .m4p:- it is the extension of Fair Play protected files.
- .mp4v:- it is the the extension of video-only.
- .m4v:- it is same as the .mp4v file format.
- .3gp, .3g2:- it is used by 3G cell phones. (It is also use to show raw file format than it does not contain *.mp4 file format)
These all above are the extensions or the type of the MP4 file format, which is also described as a MPEG-4 file format.