A camcorder is a portable consumer electronics device for recording video and audio using a built-in recorder unit. The camcorder contains both a video camera and a video recorder in one unit, hence its compound name. This compares to previous technology where an acquisition and recording devices would be separate.
The earliest camcorders, developed by companies such as JVC, Sony, Canon, and Kodak, used analog videotape. Since the 1990s recording onto digital tape has become the norm. Starting from early 2000s tape as storage media is being gradually replaced with tape-free solutions like optical disks, hard disk drives and solid-state memory.
All tape-based camcorders have removable media in form of video cassettes. Solid-state camcorders can have either removable media in form of memory cards, or built-in memory, or both. HDD-based camcorders usually have non-removable media in form of a hard disk drive.
Camcorders that do not use magnetic tape are often called tapeless camcorders. Camcorders that use two different types of media, like built-in HDD and memory card, are often called hybrid camcorders. Some prosumer level tape and solid state camcorders can use compatible secondary media such as a hard drive or an optical drive that the camera's software will control, such as in the case of the Canon and Sony prosumer unit line.
Analog vs. digital
Camcorders are often classified by their storage device: VHS, Betamax, Video8 are examples of older, videotape-based camcorders which record video in analog form. Newer camcorders include Digital8, miniDV, DVD, Hard drive and solid-state (flash) semiconductor memory, which all record video in digital form. (Please see the digital video page for details.) In older digital camcorders, the imager-chip, the CCD was considered an analog component, so the digital namesake is in reference to the camcorder's processing and recording of the video. Many next generation camcorders use a CMOS imager, which register photons as binary data as soon as the photons hit the imager and thus tightly marrying part 2 and 3.
It should be noted that the take up of digital video storage in camcorders was an enormous milestone. MiniDV storage allows full resolution video (720x576 for PAL,720x480 for NTSC), unlike previous analogue video standards. Digital video doesn't experience colour bleeding, jitter, or fade, although some users still prefer the analog nature of Hi8 and Super VHS-C, since neither of these produce the "background blur" or "mosquito noise" of Digital compression. In many cases, a high-quality analog recording shows more detail (such as rough textures on a wall) than a compressed digital recording (which would show the same wall as flat and featureless). Although, the low resolution of analogue camcorders may negate any such benefits.
The highest-quality digital formats, such as MiniDV and Digital Betacam, have the advantage over analog of suffering little generation loss in recording, dubbing, and editing (MPEG-2 and MPEG-4 do suffer from generation loss in the editing process only). Whereas noise and bandwidth issues relating to cables, amplifiers, and mixers can greatly affect analog recordings, such problems are minimal in digital formats using digital connections (generally IEEE 1394, SDI/SDTI, or HDMI).
Although both analog and digital can suffer from archival problems, digital is more prone to complete loss. Theoretically digital information can be stored indefinitely with zero deterioration on a digital storage device (such as a hard drive), however since some digital formats (like miniDV) often squeeze tracks only ~10 micrometers apart (versus ~500 μm for VHS), a digital recording is more vulnerable to wrinkles or stretches in the tape that could permanently erase several scenes worth of digital data, but the additions tracking and error correction code on the tape will generally compensate for most defects. On analog media similar damage barely registers as "noise" in the video, still leaving a deteriorated but watchable video. The only limitation is that this video has to be played on a completely analogue viewing system, otherwise the tape will not display any video due to the damage and sync problems. Even digital recordings on DVD are known to suffer from DVD rot that permanently erase huge chunks of data. Thus the one advantage analog seems to have in this respect is that an analog recording may be "usable" even after the media it is stored on has suffered severe deterioration whereas it has been noticed[1] that even slight media degradation in digital recordings may cause them to suffer from an "all or nothing" failure, i.e. the digital recording will end up being totally un-playable without very expensive restoration work.
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