MP4 player: Difference between revisions
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* [http://reviews.ebay.com.au/A-Guide-to-the-Southern-Chinese-MP4-Players_W0QQugidZ10000000001506861 A Guide to the Southern Chinese MP4 Players] |
* [http://reviews.ebay.com.au/A-Guide-to-the-Southern-Chinese-MP4-Players_W0QQugidZ10000000001506861 A Guide to the Southern Chinese MP4 Players] |
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* [http://www.s1fw.com s1 MP4 Player firmware download site] |
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[[Category:Digital audio players]] |
[[Category:Digital audio players]] |
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[[Category:Portable media players]] |
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Revision as of 14:50, 4 May 2008
MP4 players are portable media players developed in the People's Republic of China and surrounding regions which support the MPEG-4 video format.
A majority of these players are actually incompatible with the format, and are limited to low-grade proprietary formats,[1] that are considered to be cheaper alternatives for these players.
Chipsets
Fuzhou Rockchip Electronics's video processing Rockchip has been incorporated into many MP4 players, supportingAVI with no B frames in the xvid codec, while MP2 audio compression is used.[2] Some players, like the Onda VX979+, have started to use chipsets from Ingenic, which are capable of supporting RealNetworks's .RM and .RMVB video formats.[3] Also, players with SigmaTel-based technology are compatible with SMV (SigmaTel Video).
AMV
The image compression algorithm of this format[4] is inefficient by modern standards (about 4 pixels per byte, compared with over 10 pixels per byte for MPEG-22 / DVD video), with a typical resolution of 128 × 96 pixels and a framerate of 12 fps. A 30-minute video will be compressed into just 80 MB with a very lossy bitrate.[5]
MTV
The MTV video format (no relation to the cable network) consists of a 512-byte file header, which operates by displaying a series of raw image frames during MP3 audio playback.[5] As an MTV video is playing, audio frames are passed to the chipset's decoder, while the memory pointer of the display's hardware is simply adjusted to the next raw image within the video stream. This method does not require additional hardware for decoding, though it will lead to a huge consumption of memory since no compression is applied to the images. For this reason, the storage capacity of an MP4 player is effectively less than that of a player that decompresses files on the fly.
Instruction manuals
Manuals that are bundled with these players are considered to be inconsistent and are generally difficult for users to comprehend due to its poor translation.[6] Manuals may also refer to features that the particular player model may not possess. And due to the nature of the product, there is usually no contact or website information.
See also
References
- ^ Wilson, Mark (2007-12-17). "MP4 Watch Strikes Again...No Longer Plays MP4". Gizmodo. Retrieved 2008-01-09.
{{cite web}}: Check date values in:|date=(help) - ^ "Leading Chinese MP4 IC Design Houses' R&D and Product Strategies Research Report # MIC1324". Electronics.ca Publications.
- ^ "Teclast announces the M series". haomp. 2007-11-28. Retrieved 2008-03-18.
- ^ Israelsen, Paul D. (1993-09-21). "United States Patent 5247357". Retrieved 2007-12-07.
{{cite web}}: Check date values in:|date=(help) - ^ a b voroshil (2007-10-15). "AmvDocumentation". Google Code. Retrieved 2008-04-06.
- ^ "1GB Pastel Pink Mp4-Mp3 Player". Amazon.com. Retrieved 2008-01-13.