Portable media player
A portable multimedia player (PMP), sometimes referred to as a portable video player (PVP), is a consumer electronics device that is capable of storing and playing digital media. Digital audio players (DAP) that can also display images and play videos are PMPs. Like DAPs, the data is typically stored on a hard drive, microdrive, or flash memory. Other types of electronic devices like cellphones are sometimes referred as PMPs due to their playback capabilities.
History
In 2002, Archos released the first official PMP, the Archos Jukebox Multimedia.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.The Microsoft Zune, which uses a modified portable media center, would later be based on the Gigabeat S, one of the PMC-implemented players.
In 2005, Archos released the PMA400, a hybrid personal digital assistant/PMP. While its features were unmatched at the time, it was largely considered too bulky and expensive and stayed to a niche market. It would however introduce such features as WiFi and touchscreen which would become more viable for the average consumer in later years in such players as the Archos 605 WiFi and iPod Touch.
Typical features
PMPs are capable of playing digital audio, images, and video. Usually, a color LCD or 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 playersare compatible with the MP3 audio format, and many others support the Windows Media Audio (WMA) format, Advanced Audio Coding (AAC) and WAV. Some players are compatible with open-source formats like Ogg Vorbis and FLAC and others support audio with DRM protection. Every device has a bit rate limit on each audio file format supported.
Image files are usually viewed on the JPEG format and some players, like the iPod series provide compatibility to additional file formats like GIF, PNG, and TIFF.
The iPod and the PlayStation Portable are popular examples of players that support the MPEG-4 video format, and many other players are compatible with the Windows Media Video (WMV) format and the now-defunct AVI. Recently, more and more players are enabling compatibility to the DivX video format and its open-source parallel, Xvid.
PC Communication
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).
Hardware
As with DAPs, PMPs come in either flash or hard disk storage. Storage capacities have reached up to 32 GB for flash memory based PMPs, first reached by the Creative ZEN, and up to 250 GB for hard drive based, first by the Wolverine ESP 5250.
There are a number of MP3 Players featuring flash expansion slots. At first it was used to ease transfer of photos from digital cameras, using such forms as Compact Flash and Secure Digital memory. It was later popularized by a the flash memory manufacturer, SanDisk, as a form of expanding the storage capacity of flash-based players which typically holds much less than a hard disk player.
A standard PMP uses a 5-way D-pad to navigate, however there have been many alternatives used, often to win appeal. Most notable are the wheel and touch mechanisms seen on players such as the Apple iPod, SanDisk Sansa e200, and Creative ZEN Vision: M. Additional buttons are commonly seen for features such as volume control.
As needed for video and photo functions, all PMPs are equipped with color screens. 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 in Windows systems, 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.
Controversy
The AMV video formathas an inadequate image compression algorithm by modern standards. With a typical resolution of 128 × 96 pixels and a framerate of 12 fps, a 30-minute video will be compressed into 80 MB. Like AMV, many other proprietary formats like ATV, MTV, and SMV (SigmaTel Video) were meant to provide video playback for "MP4" players without increasing the cost.
