Friday, January 13, 2012

Personal Media Device


Personal Media Device
iPod Digital Media Players
Three models of Apple's popular iPod MP3 and digital media players, from left to right: iPod shuffle, iPod nano, and iPod with video. The special-edition red iPod nano was issued as part of a campaign to raise funds to fight AIDS in Africa.

Personal Media Device or Portable Media Device, handheld electronic device that plays sound and video recordings stored as digital multimedia files. Other functions and features offered by personal media devices (PMDs) may include displaying and storing photographs, access to over-the-air radio or television broadcasts, wireless Internet (Wi-Fi) access, text messaging, e-books, electronic games, video and audio recording capability, and cellular telephone access. Media files can be downloaded from personal computers or other devices that have access to the Internet or the ability to record digital media files. PMDs usually have a built-in hard drive (microdrive) or solid-state flash memory. They can run on batteries or be plugged into a power source.
Personal media devices have become a growing segment of the home electronics market, particularly MP3 players. The trend is for more types of portable electronic devices to have multimedia features. Newer models of cell phones, portable game systems, and even digital cameras also have media playback capabilities, as do some personal digital assistants. The go-anywhere convenience and on-demand entertainment made possible with these devices have made them a welcome addition to the lives of many people.
II
TYPES OF PERSONAL MEDIA PLAYERS

A
MP3 Players
Microsoft's Zune Media Player
Microsoft introduced its Zune audio player in 2006. In addition to playing MP3 audio recordings and radio broadcasts, the device can display photos and videos. It also has a wireless sharing feature so that users can send media to each other.

MP3 players are designed primarily for listening to recorded music or audio material such as podcasts, usually downloaded as files created or stored on a personal computer. Some players can also show video on a display screen. They are lightweight devices that can be held in a single hand. Many can be carried easily in a shirt pocket or strapped to an arm. Earbuds or headphones allow for private listening. MP3 players can also be plugged into speakers or other audio equipment for full sound playback. Additional capabilities include off-air radio and viewing photographs or lists of e-mail addresses or notes. Accessories such as microphones can allow MP3 players to make voice recordings.
The development of the MP3 format allowed music to be recorded in compressed digital form, requiring much less memory to store or bandwidth to download than a musical track from a CD in regular uncompressed form. The first use of MP3 format was on personal computers, allowing music and other audio files to be easily sent and downloaded over the Internet. The invention of the portable MP3 player in 1998 meant large numbers of music tracks could be stored on a small, lightweight device. MP3 players were much less bulky than portable cassette-tape players or portable CD players and did not require transporting tapes or CDs. MP3 players that used a small hard drive to store files could hold hundreds of hours of music. Music was typically downloaded to the player using a personal computer.
Apple Inc. introduced the iPod in 2001. The iPod had a hard drive and could hold thousands of songs or, in later models, display thousands of digital photographs. A user accessed the menu by touching parts of a click wheel rather than by using a keypad or switches. The iPod’s capacity, convenience, and simple design made it a major success with consumers. Later designs included a larger display screen to allow video files to be viewed and more compact iPods (iPod shuffle and iPod nano) that use flash memory instead of a hard drive. Microsoft introduced its own MP3 player called Zune in 2005.
B
Portable Multimedia Players
Portable Media Player
Many portable media players play the forms of digital entertainment that can be stored on a personal computer, including recorded television, movies, pictures, and music. This model used a hard drive to store data and an LCD screen for display.

Portable multimedia players (PMPs)—also called personal media players, portable video players, and video jukeboxes—are primarily designed for viewing video. They typically have a larger display screen than MP3 players and are held in two hands. Some models, however, are the size of MP3 players and have smaller screens. PMPs use hard drives or flash drives, and have LCD or OLED display screens. Features available include playing recorded audio and video in a number of formats, game playing, photo storage, e-book readers, off-air TV and radio broadcasts, Wi-Fi Internet connection, and video and radio recording capabilities. The first PMP was introduced in 2002 by the French company Archos.
C
Multimedia Cell Phones
Handheld mobile cellular telephones have gained enormous popularity since their introduction in the 1980s. Models have become smaller and lighter as more features have been added. Camera phones were introduced in the late 1990s, allowing users to take and send photos and later video. Computer components such as hard drives or flash drives have allowed cell phones to play and receive many types of multimedia, and perform some computer functions.
Apple Inc. introduced the iPhone in 2007 as a device that combined a mobile phone with the multimedia features of an iPod and access to the Internet. Similar handheld, all-in-one electronic devices that combine features of personal computers, media players, gaming devices, and mobile phones are likely to become much more common in the future.
D
Portable Gaming Devices
Handheld, portable gaming consoles are primarily designed for electronic games and can be interactive, permitting multiple players to participate while linked through separate devices. Gaming devices typically are held in two hands, with buttons or touch keys on each side. With many models, the display screen allows additional multimedia capabilities similar to PMPs, including wireless Internet access, playing video, or viewing photographs. Sound and music come through built-in speakers or can be listened to with earbuds or headphones.
Inexpensive handheld electronic games were first developed in the late 1970s and remained popular into the early 1990s. More sophisticated dedicated gaming devices were introduced in the late 1980s. Combination devices that offer multimedia or Internet features began to appear in the early 2000s. Such extras are now available on many models and brands.
E
Personal Digital Assistants
Personal Digital Assistant
The personal digital assistant (PDA) is a handheld computing device. Some models have multimedia playback capabilities, including MP3 files and video.

Personal digital assistants (PDAs) are handheld computers that were originally designed to help with such tasks as taking notes, scheduling appointments, and sending faxes and electronic mail. Many now have multimedia capabilities including radio, MP3, and video/audio recording, as well as e-book display. Some PDAs also have a global positioning system (GPS) link.
F
Digital Cameras
The large display screen on some digital cameras can be used to watch movies and videos. Movies or video can be downloaded from a personal computer to the cameras, which can also play sound. Some digital cameras can also be plugged into television sets to show movies, video, or photos stored on the camera.
III
CONSUMER ISSUES

A
Copyright and Intellectual Property Issues
Consumers have welcomed the ability to easily record, copy, and transfer digital multimedia files from a CD or a DVD, or from the Internet, to a personal computer and then to an MP3 player or PMP for convenient listening or viewing. However, some forms of copying are seen as piracy by the industries that claim legal and intellectual property rights over such audio and video material. Sharing of MP3 music files over the Internet in particular has led to attempts to prosecute and fine people for illegal copying. The United States Supreme Court and Congress have tried to define what constitutes fair use of copyrighted material. As the law stands, an individual who buys a CD is allowed to copy the songs to their own PC, convert the music to MP3 files, and download the files for private listening on a personal MP3 player or other device. However, supplying copies of the files to another person, even for free, is deemed illegal.
One solution to this problem has been the creation of online services such as Apple’s iTunes, Microsoft’s Zune Music Store, or AmazonMP3 that provide downloading of music files or other copyrighted material over the Internet for a fee or on a subscription basis. These purchased files may contain special coding called digital rights management (DRM) protection to prevent additional copying, or that render the files unplayable after a certain amount of time or on different kinds of digital devices. Such DRM coding and software-hardware incompatibilities have been controversial and unpopular with consumers. Some music download services and recording companies have dropped the anticopying protection features, allowing consumers to make a copy of the legally purchased music file to any device they wish, and even to copy the file onto a recordable CD or DVD. DRM may be retained for downloaded digital video files such as motion pictures, however.
B
Environmental Concerns
The convenience of personal media devices has not come without a cost. The batteries for such devices can only supply power for a limited time. The more complex the media or task, the faster the batteries may run out. Batteries can be made rechargeable and some designs that have solar panels to recharge batteries have been marketed. Electronic devices as well as the batteries to power them often contain substances such as heavy metals or toxic chemicals. Disposing of old electronics and batteries has become a serious environmental issue. Some states such as California and Washington require recycling of electronics rather than disposal in landfill sites. Manufacturing such devices may also have potentially harmful environmental effects.
C
Health Concerns
Some medical experts have raised concerns about possible health effects associated with using some personal media devices. The lightweight earbuds commonly used with MP3 players, gaming devices, and other handheld electronics fit deep in the ear. Some evidence indicates that loud volumes or listening for extended periods can damage hearing. Other concerns have been raised about cell phones held next to the head for long periods of time. Some studies suggest microwave energy broadcast by a cell phone could affect brain cells and other tissues in the head.


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