Mp4 Format Extensions

While the only official filename development described by the traditional is .mp4, various filename improvements are commonly used to indicate developed content:
MPEG-4 details information files with film and sound usually use the traditional .mp4 development.
Audio-only MPEG-4 details information files usually have a .m4a development. This is especially true of non-protected content.
MPEG-4 details information files with sound resources properly secured by FairPlay Electronic Rights Control as were promoted through the iTunes Store use the .m4p development. iTunes Plus routes, that the iTunes Store currently provides, are unencrypted and use .m4a accordingly.
Audio book and podcast details information files, which also contain meta-data such as area signs, images, and inbound links, can use the development .m4a, but more usually use the .m4b development. An .m4a sound details information file cannot "bookmark" (remember the last listening to spot), whereas .m4b development details information files can.[dubious – discuss]
The The the apple organization company iPhone uses MPEG-4 sound for its ring-tones but uses the .m4r development rather than the .m4a development.
Raw MPEG-4 Noticeable bitstreams are known as .m4v but this development is also sometimes used for film in MP4 program framework.[21]
Mobile cell mobile phones use 3GP, an performance of MPEG-4 Element 12 (a.k.a. MPEG-4/JPEG2000 ISO System Media details information file format), similar to MP4. It uses .3gp and .3g2 improvements. These details information files also store non-MPEG-4 details (H.263, AMR, TX3G).
.MP4 in comparison to .M4A[edit]
M4A seems to be for MPEG 4 Audio and is a filename development used to indicate songs.
The way of life of two different filename improvements, .MP4 and .M4A, for marking audio-only MP4 details information files has been a resource of uncertainty among clients and multi-media play-back program. Some details information file managers, such as Microsoft windows Visitor, look up the press type and associated applications of a details information file based on its filename development. But since MPEG-4 Element 14 is a program framework, MPEG-4 details information files may contain any number of sound, film, and even subtitle resources, developing it difficult to determine the type of resources in an MPEG-4 details information file based on its filename development alone. In response, The the apple organization company Inc. started using and developing popular the .m4a filename development, which is used for MP4 containers with sound details in the lossy Impressive Audio Development (AAC) or its own lossless The the apple organization company Lossless (ALAC) types. Software able of audio/video play-back should recognize details information files with either .m4a or .mp4 filename improvements, as would be expected, since there are no details framework modifications between the two. Most program able of developing MPEG-4 sound will allow the client to choose the filename development of the developed MPEG-4 details information files.

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