Canon XL1 3CCD Camcorder User Manual


 
Capturingvideo
‐Thetypeofvideo,orformat,andtoalesserextenttheconnectiontypeyouselecttocapturecontent,
candramaticallyaffectthequalityofthevideoonthecomputer.‐It’salwaysdesirabletostartwith
thehighestpossiblequalityvideoandaudiosignal.
‐Thehigherthequalityofthesourcematerialused,thehigherthequalityofthefinalcompression
results.
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Today’seditingsoftware,suchasAdobePremiere®Pro,andmanycompressionsoftwaretools,can
capturecontentinavarietyofways.Videocanbecapturedfromanalogueordigitalsources.Both
haveavarietyofdifferentvideoandaudioformatsavailableandvariousphysicalconnectiontypes
thatcanbeused.
SIGNALFORMATSANDCABLES
Analogueformats:
‐Analogvideousesfluctuatingvoltageandfrequencysignalstotransmitimage
data.
‐Rangesgreatlyinqualitybutisinherentlysusceptibletovisualinterferencefromelectronicnoiseand
suffersattenuation,orthelossofsignalpowerandqualityoverlongcableruns(usually300metersor
more).
‐Equipmentthatsupportsanalogsignalsisgenerallymoreaffordable
Becausecomputersonlyusedigitaldata,theanalogsourcemustbeconvertedtoadigitalcopytobe
captured.Whenitissentbacktoananalogmediumlikevideotape,itisconvertedbacktoananalog
signal.Thisconversioncanleadtominorerrors(quantizationerrors)beingintroduced.
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Youcanminimizethesequantizationerrorsbyusingtherightformat,goodequipment,cables,and
connections.
Composite:
‐Acompositevideosignalcarriestheluminanceandthechrominancechannelsinasinglesignal.
‐Biggestproblem=thatlumainformationcanleakintochroma,andviceversa.Thisleakagecanlead
tonoise,knownaschromacrawl,whichcanbeamplifiedbythevideocaptureprocessandreducethe
overallquality.