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Hack 11. Find Video from Across the Web

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Amongthehundredsofresultsareclipsfromprofessional

televisionnewsstoriesabouttheMarsrover,clipsfromNASA

itselfwithvideofromtheMarsrover,andamateurvideosabout

theMarsrover.Yahoo!displaysasingleframefromthevideo,

thenameofthefile,thevideo'sdimensions,andtheURLthat

containsalinktothevideoclip.Toviewavideo,justclickthe

thumbnail.Thevideowillopenfromitsoriginalsitewithina

Yahoo!frame,liketheclipshowninFigure1-31.

Thetopframeofasearchresultdetailcontainsthevideo

thumbnail,alinktoplaythevideowithinyourbrowser,anda

linktosendanemailwithalinktotheclip.Thebottomframe

showsthepagewherethevideowasfound,soyoucanseethe



videoinitsoriginalcontext.



ThevideosyoufindthroughYahoo!VideoSearchmightbeprotectedby

copyrightlaws,soyou'llneedtobemindfulofhowyouuseany

materialsyoufind.



Figure1-31.AVideoSearchresultdetailshowing

thevideoincontext



1.12.2.AdvancedVideoSearching

AswithaYahoo!WebSearch,there'sanadvancedvideosearch

form(http://video.search.yahoo.com/video/advanced).Youcan

usetheadvancedsearchformtolimitresultstospecificvideo

formats,oneofthreesizesofvideossmall,medium,or

largeandvideosthatarelongerorshorterthanoneminute.As

withtheWebSearch,youcanalsolimityoursearchtoa

specificsiteoradjusttheSafeSearchfeaturesforthesearch.

Asanexampleofaspecificsearch,youcouldstillusethe

phrasemarsrover,butlimitthesearchtoMPEGandQuicktime

filesthatareshorterthanaminutelong,smallinsize,and

foundonagovernmentdomain.Insteadofhundredsofresults

tosortthroughinabroadmarsroversearch,you'llfindfiveclips

fromaNASAsitewiththenarrowlydefinedadvancedsearch.

Iftheadvancedsearchcontrolsstilldon'tprovideenough

controloveryourquery,thereareseveralspecialsearch

keywordsyoucanusetorefineyourvideosearchesfurther.



Atthetimeofthiswriting,thesevideokeywordsaren'tdocumentedon

Yahoo!,sothanksgotoStigSætherBakkenandDavidHallfrom

Yahoo!forsharingthesyntaxelementslistedhere.



Here'salookateachofthespecialsyntaxkeywordsandhow

they'llrefineasearch.Notethatakeywordisfollowedbya

colonandavaluewithnospaceinbetween.



filesize

Limitssearchresultstofilesofaspecificsize,inbytes.You



canusethisincombinationwithagreater-thansign(>)or

less-thansign(<)tofindfilesthatarelargerorsmallerthan

thespecifiedamount,respectively.Forexample,filesize:

<1073741824limitsresultstovideofilesthataresmallerthan

onegigabyte.



date

Limitsresultstovideosthathavebeenlastmodifiedon,

before,orafteracertaindate.YouneedtouseaUnix-style

date,whichisthetimeinsecondssinceJanuary1,1970.

Soaquerythatincludesdate:>1107803581returnsresultswith

videosthathavebeenmodifiedafterFebruary7,2005.



width

Findsvideosofaspecificwidthinpixels.Aquerywith

width:640findsvideosthatare640pixelswide.



height

Findsvideosofaspecificheightinpixels.Soheight:480finds

videosthatare480pixelstall.



duration

Findsclipsofacertainlengthinseconds.Asyou'dexpect,

duration:>30limitsresultstovideoslongerthan30seconds,

andduration:<30limitsresultstovideosthatareshorterthan

30seconds.



tld

Findsvideosthatarehostedonaspecifictop-leveldomain

(aphraseforwhichthekeywordtldisanabbreviation),

suchas.org,.com,.gov,.edu,oraspecificcountytop-level

domain,suchas.jpforJapan.



fromtld

Narrowsresultstovideosthathavebeenreferencedona

pageataspecifictop-leveldomain,becausesomesitescan

linktovideosonotherdomains.Soeventhougha

particularvideomightresideat.comaddress,Yahoo!might

haveindexedthevideoviaapageatan.edudomainthat

linkedtothevideo.Thesyntaxfromtld:edufindsvideosthat

havebeenreferencedinpagesat.edudomains.



site

Searchesforvideosataspecificsite.Thesyntax

site:nasa.govlimitsresultstovideoshostedat

http://www.nasa.gov.



fromsite

Limitssearchresultstopagesthatreferencevideosatthe

specifiedsite.Whilethesitespecifiedmightnothostvideos,

thisspecialsyntaxstillensuresthatpageswithlinksto

videosfromthesiteareincluded.



title

Limitssearchresultstovideoclipswithspecificwordsinthe

video'sfilename.Asearchwithtitle:roverreturnsonly

videoswithroverinthefilenameorlinktext.



fromtitle

Limitsresultstowordsinareferringdocument'stitle.The

syntaxfromtitle:roverfindsvideosthathavebeenreferenced

onpageswithroverinthefilename,eventhoughtheword

rovermightnotappearinthenameofthevideofile.

Afinalspecialkeyword,aspect,letsyoulimitsearchresultsto

videofileswithaspecificaspectratio.Theaspectratiorefersto

avideo'sdisplaywidthdividedbyitsheight.Astandard

televisionscreenisalmostsquare,butitswidthisabitlonger

thanitsheight.Theaspectratioofastandardtelevisionscreen

isnotedas4:3.Thenewerhigh-definitiontelevisionscreensare

muchlongerthantheyarewide,andtheiraspectratioisnoted

as16:9.Naturally,thevideoforeachofthesedevicesmatches

theproperaspectratio.

Theaspectkeywordexpectsastandardsingleintegerto

representanaspectratio,soyou'llneedtodoalittlemath

beforeyouuseit.Theformulaisthevideowidthmultipliedby

100,thendividedbytheheightandroundeddownifnecessary.

Tomakethingseasy,herearethemostcommonaspectratios,

alongwiththecomputedvalueyou'dusewiththeaspect

keyword:

Table1-4.

Aspectratio

Television(4:3)



Computedvalue

133



Computermonitors(5:4)



125



WidescreenmoviesandHDTV(16:9)



177



Forexample,usingaspect:177inavideosearchquerylimitsthe

resultstofilesthatareinawidescreenformat.



YoucanalsousethespecialvideosyntaxwiththeYahoo!VideoWeb

Servicesifyouwantprogrammaticaccesstovideosearchresults.Read

thefulldocumentationfortheserviceat

http://developer.yahoo.net/video/V1/videoSearch.html.



Youcanusethesespecialsyntaxelementsincombinationto

buildsomefairlysophisticatedqueries.Yahoo!Movies

(http://movies.yahoo.com)hostshundredsofmoviepreviews

andclips,andyoucanfindafulllistingat

http://movies.yahoo.com/trailers.Thesitedoesn'toffer

thumbnailbrowsingofitsarchive,butyoucaneasilysee

thumbnailsoftheclipsavailablewithanadvancedYahoo!Video

Search.Searchforsite:yahoo.commatrixtoseethumbnailsof

videoclipsandtrailersfromthethreeMatrixmovies.



Hack12.StreamlineBrowsingwiththeYahoo!

Toolbar



TheYahoo!ToolbarintegratesYahoo!withyourweb

browser,lettingyousearch,customizefeatures,and

accessyourmailfromthebrowseratalltimes.

TheYahoo!ToolbarisabrowserextensionofferedbyYahoo!

thatintegratesmanyofYahoo!'sfeatureswithyourweb

browser.Afterinstallingthetoolbar,you'llfindanextrarowof

buttonsinyourbrowser,asshowninFigure1-32.



Figure1-32.TheYahoo!Toolbar



ThetoolbarcontainsbuttonsthatperformYahoo!-specific

functionsandasearchformforquickaccesstoYahoo!

searching.Thetoolbarcanprovideone-clickaccesstoallof

yourpagesatYahoo!,includingyourmail,groups,calendars,

addressbook,andstockquotes.Thetoolbariscompletely

customizable,andyoucanchoosewhichbuttonsandYahoo!

featuresareavailableonthetoolbar.BecauseYahoo!makes

mostofitsfeaturesavailableviathetoolbar,youcantailoryour

toolbartosuitthewayyouuseYahoo!.



1.13.1.Installation

ToinstalltheYahoo!Toolbar,pointyourbrowserto

http://toolbar.yahoo.comandclicktheorangeDownloadbutton.



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