Tải bản đầy đủ - 0 (trang)
Hack 71. Create a Shadow for a Green Screen Image

Hack 71. Create a Shadow for a Green Screen Image

Tải bản đầy đủ - 0trang

Thefirststepincreatingyourshadoweffectistoduplicateyourvideoimage.To

doso,simplycreateanothervideolayeronyourtimelineanddropacopyof

yourgreenscreenvideoontoit.Youwillwanttoapplythesameexacteffectyou

usedtoinitiallycompositeyourscene[Hack#70].Whenpreparedcorrectly,you

shouldhavetwolayersofvideo,withthesameeffectsapplied.



Thebestapproachtoduplicatingagreen-screenedimageistocopyand-pasteitintothetimeline.Afterapplyingthenecessaryeffectsto

keyoutthegreenscreenontheoriginalimage,copytheentireclip,

includingtheeffects,andpasteittoanother(lower)layeronyour

timeline.Thismightrequireshufflingyourfootageontonewlycreated

layersinyourtimeline.



6.12.2.LayeringVideotoPrepareforShadowCreation

Inorderfortheeffecttoappearcorrectly,youwillwantyouroriginalimageona

layerabovetheshadowimage'slayer.Ifyoudonotdostackthelayerscorrectly,

theshadowwillappearinfrontofyoursubject.Figure6-40showsthedifference

betweenhavingtheshadowlayerabovetheoriginallayerandbelowtheoriginal

layer.

Figure6-40.Thesubtlebutdistinctdifferenceinlayering



6.12.3.CreatetheShelloftheShadow



Nowthattheimagelayershavebeenprepared,youneedtoremovethecolor

fromtheimage.Byremovingthecolor,youshouldendupwithablack

representationofyouroriginalimage.Toaccomplishthis:



Avid

OpentheEffectEditorfortheclipandchooseShowAlpha.



WithAvid,bychangingthekeytoamovingmatte,viathe

ShowAlphaoption,anyadditionaleffectsyouapplyare

independentofanyotherlayers.Aftercreatingthemoving

matte,applyapainteffecttotheclip,tonestthekey

effect:

Tools



EffectsPalette



Image



PaintEffect



Then,dragamattekeyontopofthepainteffect,to

providetheshadow:

Tools



EffectsPalette



Key



MatteKey



FinalCut

Effects



VideoFilters



ImageControl



VideoEffects



Adjust



BrightnessandContrast



Premiere

Effects



BrightnessandContrast



6.12.4.SheartheShadowOffoftheSubject



Onceyouhavecreatedthebasicshadowelement,youneedtoshearitaway

fromyoursubject.Ifyoudon'tsheartheshadowimage,youraudiencewillnever

seeitbecauseitwillalwaysbebehindyouroriginalimage.Toshearyourimage,

youneedtodistortit:



Avid

Tools



EffectsPalette



Blend



3DWarp



FinalCut

Effects

Tool)



VideoFilters



Perspective



VideoEffects



Distort



Basic3D(orusetheDistort



Premiere

Effects



CornerPin



Gettingyourshadowtofitthescenetakestimeandpatience.



TherearenospecificrulesIcanprovidetoshearyourshadowrealistically

becauseeveryshotwillrequiredifferentsettings.Ifthereareothershadowsin

yourbackground,usethemasareferencepointtohelpevaluatehowwellyour

settingsmatchthescene.



6.12.5.AddSubtletytotheShadow

Dependingonyourpersonalpreference,aswellasanypreexistingshadowsin



yourscene,youwillpossiblywanttoblendyournewshadow.Blendingthe

shadowiseasytodo:justchangeitsopacity.Inordertoaddalittlemore

realism,youcanaddaBlureffecttoyourshadowinordertosoftenit.

Ifyouwanttoadjustanyoftheparametersonyoureffect,simplyedittheeffects

you'veapplieduntilyouobtainacceptableresults.Again,ifthereareany

preexistingshadowsinyourscene,youshouldattempttomatchyourselfcreatedshadowasmuchaspossible.Figure6-41showsaseriesofimagesfrom

acompletedscenewithandwithoutashadowapplied.

Figure6-41.Acompletedscenewith(top)andwithout(bottom)

shadowapplied



6.12.6.HackingtheHack

Therewillusuallybefinal,smalldetailsthatyouneedtopayattentionto.You

willmorethanlikelyhavetoperformsomeminoradjustmentstoyoursubject

image,includingchangingbrightnessandcontrasttomatchyourbackground.

Youmightalsohavetodosomecolorcorrectioninordertohaveyouroriginal

imageblendincorrectly.

Whenyou'vefinishedcompositingyourshadow,trytogglingyourshadowlayer

onandoff,merelytoremindyourselfthatyou'vecreatedashadowthatfollows

yoursubjects…justliketherealthing.



Hack72.AlternateEndingsBasedontheTime

ofDay



Analternateendingismerelyadifferentendingtoamovie,asopposedto

theoneshownintheofficialrelease.Usingsomeofthehiddenfeaturesin

QuickTime,availablethroughTotallyHip'sLiveStagePro,youcanprovide

analternateendingtoyourmoviebasedonthetimethevieweriswatching

it.

YoumightremembertheChooseYourOwnAdventurebookswhere,attheend

ofachapter,youwereabletochooseoneofahandfulofoptions.Basedonyour

choice,youwouldthenjumptoaspecificpageinthebook,wherethestory

wouldresume.Thestorywouldunfoldbasedonthechoicesyoumadeandyou

couldreadthebookmanytimesover,eachtimewithadifferentout-come.

Readingisaneasilyadaptablemediumforinteraction,butvideoisnot.People

watchvideopassively;otherwise,theyplayvideogames,whichareinteractive.

So,howcanweadaptthepassivemediumofvideotosomethingthatis

interactive?Onewayisthroughtime;dependingonthetimethevideois

watched,certainsceneswillpresentthemselves.

UsingTotallyHip'sLiveStagePro(http://www.totallyhip.com;$449.95)you'll

beabletocreatemoviesthatcanalternatescenesbasedonthetimeofday.



6.13.1.PlanningforPassiveInteraction

Thefirststepincreatingapassive-interactivevideoistoplanahead.Justlikethe

ChooseYourOwnAdventurebooks,youwillneedtoplanfortheoccurrences

youwanttopresentandshoottheappropriatescenes.Forsimplicity,youshould

startwithonlyonealternateending,whichmeansyouneedtoshootatotalof

twoendings.Asyougetusedtothistypeofvideo,youcancreateascomplexa

movieasyoulike.



Youwillnotwanttoaddtheinteractivityuntilafteryouhavecompletedediting

yourmovie.Uponcompletion,youshouldoutputthreedigitalmovies:

Theentiremovie,minustheending

Theoriginalending

Thealternateending

Youwillcompilethesemoviesintoone,finalmoviefordistribution.



6.13.2.CreatingYourProject

StartanewprojectinLiveStageProandchooseEdit DocumentSettings…to

changesomeofthepropertiesofthemovie.UnderthePlaybacktab,changethe

Transport Controller:pop-uptoStandardMovie.Thiswillplacethefamiliar

timeindicatoratthebottomofthemovie,alongwithaPlay/Pausebuttonand

volumecontrols.

UndertheSettingstab,changethewidthandheightofthemovieto720andto

480,respectively(720x576forPAL).

Ifyouwouldliketoannotateyourmoviewithyourname,somecomments,or

anddisclaimers,forexampleyoucandosoundertheAnnotationstab.



6.13.3.ImportingYourMovies

LocateyourcompletemovieonyourharddriveanddragitontoyourLive-Stage

Protimeline.ThevideoandaudiotrackswillbeseparatedoutandlabeledVideo

1andSound1,respectively.Youcanchangetheirlabelsbydouble-clickingon

thelabelontheleftsideofthewindow.Thiswillopenawindow,allowingyou

tochangethenameofthetrack,theheightandwidth,andawholebunchof

otherdetails(whichdonotpertaintothishack).

6.13.3.1.Addingtheendings.



Tài liệu bạn tìm kiếm đã sẵn sàng tải về

Hack 71. Create a Shadow for a Green Screen Image

Tải bản đầy đủ ngay(0 tr)

×