Digital video is a blazon of video recording arrangement that works by application a digital, rather than analog, representation of the video signal. This all-encompassing appellation is not to be abashed with the name DV, which is a specific blazon of agenda video. agenda video is best about recorded on tape, afresh advertisement on optical discs, usually DVDs. There are exceptions, such as camcorders that almanac anon to DVDs, Digital8 camcorders which encode agenda video on accepted analog tapes, and the best contempo JVC Everio G camcorders which almanac agenda video on adamantine disks.
The agreement "camera", "video camera", and "camcorder" are acclimated interchangeably in this article.
Introduction
Video cameras appear in two altered angel abduction formats: interlaced and accelerating scan. Interlaced cameras almanac the angel in Alternating sets of lines: the odd-numbered curve are scanned, and afresh the even-numbered curve are scanned, afresh the odd-numbered curve are scanned again, and so on. One set of odd or alike curve is referred to as a "field", and a after bond of two fields of adverse adequation is alleged a frame.
A accelerating scanning agenda video camera annal anniversary anatomy as distinct, with both fields actuality identical. Thus, interlaced video captures alert as abounding fields per additional as accelerating video does back both accomplish at the aforementioned cardinal of frames per second. This is one of the affidavit video has a "hyper-real" look, because it draws a altered angel 60 times per second, as against to film, which annal 24 or 25 accelerating frames per second.
Progressive browse camcorders such as the Panasonic DVX100 are about added adorable because of the similarities they allotment with film. They both almanac frames progressively, which after-effects in a crisper image. They can both shoot at 24 frames per second, which after-effects in motion strobing (blurring of the accountable back fast movement occurs). Thus so, accelerating scanning video cameras tend to be added big-ticket than their interlaced counterparts. (Note that alike admitting the agenda video architecture alone allows for 29.97 interlaced frames per additional [or 25 for PAL], 24 frames per additional accelerating video is accessible by announcement identical fields for anniversary frame, and announcement 3 fields of an identical angel for assertive frames. For a added abundant explanation, see the adamwilt.com link.)
Standard blur stocks such as 16 mm and 35 mm almanac at 24 or 25 frames per second. For video, there are two anatomy amount standards: NTSC, and PAL, which shoot at 30/1.001 (about 29.97) frames per additional and 25 frames per second, respectively.
Digital video can be affected with no abasement in quality. No amount how abounding ancestors a agenda antecedent is copied, it will be as bright as the aboriginal aboriginal bearing of agenda footage.
Digital video can be candy and edited on an NLE, or non-linear alteration station, a accessory congenital alone to adapt video and audio. These frequently can acceptation from analog as able-bodied as agenda sources, but are not advised to do annihilation added than adapt videos. agenda video can additionally be edited on a claimed computer which has the able accouterments and software. application a NLE station, agenda video can be manipulated to chase an order, or sequence, of video clips. Avid's software and accouterments is about alike with the able NLE market, but Apple's Final Cut Pro, Adobe Premiere, and agnate programs are additionally popular.
More and more, videos are edited on readily available, added affordable accouterments and software. alike abounding account films, such as Cold Mountain, accept been edited absolutely on Final Cut Pro, Apple's non beeline alteration software.
Regardless of software, agenda video is about edited on a bureaucracy with abounding deejay space. agenda video activated with accepted DV/DVCPRO compression takes up about 250 megabytes per minute or 13 gigabytes per hour.
Digital video has a decidedly lower amount than 35 mm film, as the tapes can be beheld on area after processing, and the band banal itself is actual bargain (about $3 for a 60 minute MiniDV tape, in bulk, as of December, 2005). By comparison, 35 mm blur banal Costs about $1000 per minute, including processing.
Digital video is acclimated alfresco of cine making. agenda television (including college affection HDTV) started to advance in best Developed countries in aboriginal 2000s. agenda video is additionally acclimated in avant-garde adaptable phones and video conferencing systems. agenda video is additionally acclimated for Internet administration of media, including alive video and peer-to-peer cine distribution.
Many types of compression abide for confined agenda video over the internet, and assimilate DVD's. While DV video is not aeroembolism above its own codec while editing, the book sizes that aftereffect are not applied for commitment assimilate optical discs or over the internet, with codecs such as the Windows Media format, MPEG2, MPEG4, Real Media, the added contempo H.264, and the Sorenson media codec. Probably the best broadly acclimated formats for carrying video over the internet are MPEG4 and Windows Media, while MPEG2 is acclimated about alone for DVD's, accouterment an aberrant angel in basal admeasurement but consistent in a aerial akin of CPU burning to decompress.
As of 2005, the accomplished resolution approved for agenda video bearing is 33 megapixels (7680 x 4320) at 60 frames per additional ("UHDV"), admitting this has alone been approved in appropriate class settings [1]. The accomplished acceleration is accomplished in automated and accurate aerial acceleration cameras that are able of filming 1024x1024 video at up to 1 actor frames per additional (for actual abbreviate time, obviously).
2006 Cordin is the apple baton in ultra aerial acceleration imaging technology.
Depending on the camera arrangement in use anatomy ante up to 200 000 000 frames per additional are possible. actual abbreviate affiliation times and inter anatomy times are standard. Gated and agitated models are available. Among added modules Cordin offers Ultra-High acceleration Camera systems with 1000 * 1000 Pixel at abounding anatomy amount in colour or atramentous and white . Streak camera systems for accurate applications are accessible and Developed with avant-garde technology.
For aerial acceleration applications in the near, average or continued beachcomber bittersweet the Phoenix cameras action assorted possibilities. The InGaAs, QWIP and InSb Detectors can access images with a anatomy amount of up to 30 KHz in the amicableness ambit of 900 nm to 10 µm.
interfaces/cables
Many interfaces accept been advised accurately to handle the requirements of uncompressed agenda video (at almost 400 Mbits/s):
Serial agenda Interface
FireWire
High-Definition Multimedia Interface
Digital Visual Interface
Unified Display Interface
DisplayPort
Storage formats
Encoding
All accepted formats, which are listed below, are PCM based.
CCIR 601 acclimated for advertisement stations
MPEG-4 acceptable for online administration of abounding videos
MPEG-2 acclimated for DVDs and Super-VCDs
MPEG-1 acclimated for video CDs
H.261
H.263
H.264 additionally accepted as MPEG-4 Part 10, or as AVC
Theora connected but still in development. acclimated for video over the internet.
Tapes
Betacam SX, Betacam IMX, agenda Betacam
D1, D2, D3, D5, D9 (also accepted as Digital-S)
DV, MiniDV - acclimated in best of today's customer cameras
DVCAM, DVCPRO - acclimated in able advertisement operations
Digital8 -
Disks
Video CD (VCD)
DVD
HD-DVD
Blu-ray Disc
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