Information AboutMp4 |
| CATEGORIES ABOUT MPEG-4 PART 14 | |
| container formats | |
| mpeg | |
MPEG-4 Part 14, formally Container Format standard specified as a part of MPEG-4 . It is most commonly used to store Digital Audio and Digital Video streams, especially those defined by MPEG , but can also be used to store other data such as Subtitles and still images. Like most modern container formats, MPEG-4 Part 14 allows Streaming over the Internet . The official Filename Extension for MPEG-4 Part 14 files is '''.mp4''', thus the container format is often referred to simply as '''MP4'''. Devices that play .mp4 files are referred to as MP4 players. HISTORY OF MP4 MPEG-4 Part 14 was based on Apple 's Quicktime Container Format .1 MPEG-4 Part 14 is essentially identical to the QuickTime MOV format, but formally specifies support for Initial Object Descriptors (IOD) and other MPEG features.http://lists.apple.com/archives/Streaming-server-developers/2001/Dec/msg00016.html .MP4 versus .M4A file extensions The existence of two different file extensions for naming audio-only MP4 files has been a source of confusion among users and multimedia playback software. Since MPEG-4 Part 14 is a container format, MP4 files may contain any number of audio, video, and even subtitle streams, making it impossible to determine the type of streams in an MP4 file based on its filename extension alone. In response, Apple Inc. started using and popularizing the .m4a file extension. Software capable of audio/video playback should recognize files with either .m4a or .mp4 file extensions, as would be expected, as there are no file format differences between the two. Most software capable of creating MPEG-4 audio will allow the user to choose the filename extension of the created MPEG-4 files. While the only official file extension defined by the standard is .mp4, various file extensions are commonly used to indicate intended content:
The common, but non-standard use of the extensions .m4a and .m4v is due to the popularity of Apple 's IPod and the ITunes Store . DATA STREAMS Almost any kind of data can be embedded in MPEG-4 Part 14 files through ''private streams''; the widely-supported Codecs and additional data streams are:
Some private stream examples include Nero 's use of DVD subtitles (''Vobsub'') in MP4 files. M4P to MP3 Conversion Methods There are two other methods to convert M4P to MP3 by bypassing the DRM control. The first method is to burn a copy to an audio CD and then Rip it. Some software products take an even simpler and more automated method which allows user to burn music to a Virtual CD-RW disc and then automatically rip and encode the music stored on the Virtual CD-R. NoteBurner M4p Converter is the typical example which uses this Virtual CD-RW drive method. The second method is to use a recording software and sound card (utilizing the so-called " Analog Hole "). NOTES
SEE ALSO
Competing technologies
Compatible software
Compatible hardware
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