A portable media player (PMP) is a consumer electronics device that is capable of storing and playing digital media like audio, images, video, documents, etc. Digital audio players (DAP) that can also display images and play videos are usually called PMPs. Like DAPs, the data is typically stored on a hard drive, microdrive, or flash memory. Other types of electronic devices like cellphones, internet tablet, and digital cameras are sometimes referred as PMPs because of their playback capabilities. [1]This article however focuses on portable devices that have the main function of playing media.
Contents |
The iPod is a portable media player designed and marketed by Apple and launched on October 23, 2001.
In 2002, Archos first widely sold a portable media player, the Archos Jukebox Multimedia.[2] Manufacturers have since implemented abilities to view images and play videos into their devices.
In 2004, Microsoft attempted to take advantage of the growing PMP market by launching the Portable Media Center (PMC) platform. It was introduced at the 2004 Consumer Electronics Show with the announcement of the Zen Portable Media Center,[3] which was co-developed by Creative. The Microsoft Zune series would later be based on the Gigabeat S, one of the PMC-implemented players.
PMPs are capable of playing digital audio, images, and video. Usually, a colour liquid crystal display (LCD) or organic light-emitting diode (OLED) screen is used as a display. Various players include the ability to record video, usually with the aid of optional accessories or cables, and audio, with a built-in microphone or from a line-out cable or FM tuner. Some players include readers for memory cards, which are advertised to equip players with extra storage or transferring media. In some players, features of a personal organizer are emulated, or support for games, like the iriver clix (through compatibility of Adobe Flash Lite) or the PlayStation Portable, is included.
Nearly all players[4] are compatible with the MP3 audio format, and many others support Windows Media Audio (WMA), Advanced Audio Coding (AAC) and WAV. Audio files purchased from online stores or ripped from CDs may include Digital Rights Management (DRM) copy protection, which most modern players support. Some players are compatible with open-source formats like Ogg Vorbis and the Free Lossless Audio Codec (FLAC). Every device has a bitrate limit on each compatible format.
The JPEG format is compatible on all players that are capable of displaying images. Some players, like the iPod series, provide compatibility to display additional file formats like GIF, PNG, and TIFF, while others are bundled with conversion software.
Most newer players support the MPEG-4 video format, and many other players are compatible with Windows Media Video (WMV) and AVI, now mostly used as a container format. Recently, more and more players are enabling compatibility to the DivX video format and its open-source parallel, Xvid. Software included with the players may be able to convert video files into a compatible format.
PMPs are usually packaged with an installation CD/DVD that inserts device drivers (and for some players, software that is capable of seamlessly transferring files between the player and the computer). For recent players, however, these are usually available online via the manufacturers' websites, or natively recognized by the operating system through Universal Mass Storage (UMS) or Media Transfer Protocol (MTP).
As with DAPs, PMPs come in either flash or hard disk storage. Storage capacities have reached up to 64 GB for flash memory based PMPs, first reached by the 3rd Generation iPod Touch, and up to 500 GB for Hard disk drive PMPs, first achieved by the Archos 5 Internet Tablet.
A number of players support memory card slots, including CompactFlash (CF), Secure Digital (SD), and Memory Sticks. They are used to directly transfer content from external devices, and expanding the storage capacity of PMPs.
A standard PMP uses a 5-way D-pad to navigate, however there have been many alternatives used. Most notable are the wheel and touch mechanisms seen on players from the iPod and Sansa series. Another popular mechanism is the swipe-pad, or 'squircle,' first seen on the Zune. Additional buttons are commonly seen for features such as volume control.
Sizes range all the way up to 7 inches. As well, resolutions also vary, going up to WVGA. Most screens come with a color depth of 16-bit, but higher quality video oriented devices may range all the way to 24-bit, otherwise known as Truecolor, with the ability to display 16.7 million distinct colors. Screens commonly have a matte finish but may also come in glossy to increase color intensity and contrast. More and more devices are now also coming with touch screen as a form of primary or alternate input. This can be for convenience and/or aesthetic purposes. Certain devices, on the other hand, have no screen whatsoever, reducing costs at the expense of ease of browsing through the media library.
Some portable media players include a radio receiver, most frequently receiving FM.
Some portable media players have recently added features such as simple camera, built in game emulation (playing Famicon or other game formats from ROM images) and simple text readers and editors.
|
|