Today's Featured Article - MP4
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MPEG-4 Part 14 or *.mp4, is a file format (a so called container) specified as a part of the ISO/IEC MPEG-4 international standard. It is used to store media types defined by the ISO/IEC Moving Picture Experts Group, and can be used to store other media types as well. It is, or will be, typically used to store data in files, though it will be used in data streams and possibly in other ways.
*.mp4 allows streaming over the internet. It also allows multiplexing of multiple video and audio streams in one file, variable frame- and bit-rates, subtitles and still images. Apple's QuickTime file format was the design starting point of the *.mp4 file format. Although *.mp4 still resembles the QuickTime format, it has been improved upon in many different ways.
Almost any kind of data can be embedded in *.mp4 files through private streams, but those that are recommended (for compatibility reasons) are:
* Video: MPEG-4 (particularly part 2, and part 10 -- also known as AVC or H.264), MPEG-2 and MPEG-1
* Audio: MPEG-4 AAC, MP3, MP2, MPEG-1 Part 3, MPEG-2 Part 3, CELP (speech), TwinVQ (very low bitrates), SAOL (midi)
* Pictures: JPEG, PNG
* Subtitles: MPEG-4 Timed Text, and/or xmt/bt text format (means that subtitles have to be translated into xmt/bt)
* Systems: Allows animation, interactivity and DVD-like menus
Some file extensions used on files that contain data in the *.mp4 format:
* .mp4: official extension, for audio, video and advanced content (see above) files
* .m4a: for audio-only files; can safely be renamed to *.mp4, though opinions differ on the wisdom of this.
* .m4p: FairPlay protected files
* .mp4v, .m4v: video-only (sometimes also used for raw mpeg-4 video streams not in the *.mp4 container format)
* .3gp, .3g2: used by 3G mobile phones, may also store content not specified directly in the *.mp4 specification (H.263, AMR, TX3G)
On October 30, 2005, Gabest added splitter support for *.mp4 in MPC. -
wat is the difference between mp3 and 4?
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With mp4, you can get video. -
iPod Video does play .mp4 files as well, though there is a limit of 2.5Mb per file.Originally posted by PriscillaTang in "Chit Chat":I've seen quite a few selling MP4 players on many forums. Could someone kindly explain to me what are their uses? Ive seen most can play videos, read txt files etc. Since the use is so good, why does it seems not many pple are using it? And the prices are fairly cheap too. $120 for a 256mb. With a player that comes with so many functions, why is it not popular? Is it being big industry players like IPOD and Creative hasn't come up with any of these yet so pple are still unsure of whether to buy or not?
Creative has a similar product that uses organic LED's.
the only qualm with them is the small screen. do users really want to sacrifice that for the convenience of being able to view videos everywhere they go? it's up to the consumer.
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can watch and listen to music mtv ....... cool
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There is no limit for the file size of mp4 on iPod. In fact, you can set the resolution of an mp4 video to double that of the iPod (double 320x240, which is 640x240) if you intend to play the video from your iPod on a bigger screen. I've been encoding movies into mp4 for my iPodOriginally posted by ^tamago^:iPod Video does play .mp4 files as well, though there is a limit of 2.5Mb per file.
Creative has a similar product that uses organic LED's.
the only qualm with them is the small screen. do users really want to sacrifice that for the convenience of being able to view videos everywhere they go? it's up to the consumer.