Streaming Media Production Best Practices Streaming Media East – May 16 th, 2005 Steve Mack, LUX Media smack@luxmedia.com.

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  • Streaming Media ProductionBest PracticesStreaming Media East May 16th, 2005

    Steve Mack, LUX Mediasmack@luxmedia.com

    SxSW Interactive Conference

  • What Is Not CoveredAny particular streaming media platformQuickTime, RealSystem and Windows Media all shownAlternative data typesFlash animation, text, images, etc.Advanced authoringJavaScript, VB, SMIL, MPEG 4ServingBusiness ModelsAdvertising, Pay-Per-View, etc.Digital Rights ManagementSecuring your content

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  • Todays AgendaPart I The Basics (~1 hour)Terminology, basic conceptsPart II Creation (~2 hours)AudioVideoPart III Encoding (1 hour)Encoding BasicsAdvanced EncodingPlatform specific examplesPart IV - Authoring (1 hour)Authoring Basics (metafiles)Advanced Authoring (embedded players)Part V Live Broadcasts (time allowing)

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  • Agenda Part IBasic ConceptsStreaming Media System Components & TerminologyThe Streaming Media ProcessTools of the tradeStreaming Media TechnologiesQuickTimeRealSystemWindows MediaFlash MXMPEG 4

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  • Internet Access Devices, Worldwide(millions)1 BillionSources: Cahners In-Stat Group

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  • What Does It All Mean?Streaming media is a new mass mediumCurrently in its second waveNew platform(s) for media deliveryHuge audienceHuge opportunityEntertainment, business, education, you name itWont last forever

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  • We believe you.Get to the point.

    Okay, I will. Lets start at the beginning

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  • Streaming is not DownloadingStreamingReal timeLive or on demandNot stored locallyDownloadingEntire file must downloadNot real time, not live, and stored locallyProgressive DownloadHybrid approachPlayer estimates how much to bufferCan be very effective for short-form contentAdvantages and disadvantages of downloading

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  • How Streaming Media WorksEncoding software converts raw media into a format that can be streamedAudience uses player software (RealOne, QuickTime, Windows Media) to watch/listen.Serving software distributes the streams to listeners

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  • Streaming Media System ComponentsPlayersQuickTime, RealPlayer, Windows Media Player, etc.ServersServers are specialized computers built specifically to serve user requestsEncodersEncoders can be hardware or software, available from a number of manufacturersAll streaming media systems are built from these three basic building blocks

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  • Streaming Media Delivery MethodsUnicastEach user receives an individual streamDoesnt scale wellMulticastA single copy of the stream is sent outEach viewer grabs a copyRequires all routers to be multicast-enabledOnly suitable for live broadcastsDoesnt work on todays internetMany Internet broadcasts (webcasts) are done using a combination of the two

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  • Streaming Media Delivery MethodsUnicast or multicast to secondary serversUnicast or multicast to local clients

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  • Streaming Media TerminologyProtocolsDetermine how components communicate (RTSP, RTP, MMS, HTTP, TCP/IP, UDP)File FormatsHow the data is structuredGenerally proprietary (except for MPEG4) (.asf, .rm, .qt, etc.)CodecsContraction of coder-decoder (or compressor decompressor)Software that reduces the data rate of media files Codecs are necessary because

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  • Bandwidth Is EverythingBandwidth is the measurement of how much data can be received in real timeStreaming media delivery is limited by audience bandwidthAvailable bandwidth determines quality How best to utilize available bandwidth?Screen sizes for videosQuality of audioHow much free bandwidth to leave

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  • The Streaming Media ProcessProductionA/V Production, digitizing the raw media files, editingEncodingConverting to a streaming formatAuthoringConnecting the audience to your contentCreating an interface for your content Combining multiple data typesServingDistributing your content to the public

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  • Streaming Media ToolsProduction ToolsAudio/Video equipment, editing hardware/softwareEncoding ToolsEncoding hardware/softwareAuthoring ToolsAuthoring software (WYSIWYG, text editors)Serving ToolsServer hardware

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  • Tools of the TradeAudio Good source: good microphone, mixing deskSignal processing: compressor, EQ unit proper recording environment

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  • Tools of the Trade (contd)VideoGood camera: DV is most cost-efficient, FireWire optionBuy the best tripod you can afford!Lighting: 3-point lighting kit

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  • Tools of the Trade (contd)Computer HardwareNo such thing as too much CPU/RAM/storageProfessional sound cards sound betterUSB audio interfaces a new optionFireWire cards best bet for video captureSoftwareAudio and video editing software, encoding software

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  • Streaming Media Systems - The Big ThreeQuickTimeCurrent version 7.0 (Mac OSX), 6.5 (Win)Sorenson and MPEG-4 (H.264) codecsFree server & player; QuickTime Pro $29.95Windows MediaCurrent version Player 10 (Win XP only), 9 series player and encoder (no live encoding on Mac)Windows Media codecsFree player, encoder & utilities; Windows Server 2003RealSystemCurrent version RealPlayer & RealProducer 10, Helix Server RealAudio & RealVideo codecs, also plays back & streams QuickTime & Windows MediaLicensed server, free player & encoder

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  • Streaming Media Systems - New Kids on the BlockFlash MXCurrently on version 1.5Sorenson codec (recently licensed VP6)Streaming requires Flash Player 7, Sorenson Squeeze or QuickTime Pro encoding, Flash MX required for streaming and authoringMPEG 4ISO standard (Moving Picture Experts Group)A standardized framework for interactive media, including streaming, including a file format & codecQuickTime & RealPlayer support

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  • Streaming Media in ActionQuickTimeQuickTime ProRealSystemReal Player 10, RealProducer 10Windows MediaWindows Media 9 SeriesFlash MXVersion 1.5MPEG 4Sorenson Squeeze

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  • Quick BreakComing Up: Part II - Production

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  • Agenda Part IIStreaming Media Process RecapCodecsWhat they are and why theyre necessaryCreation AudioAudio CodecsProduction TipsProcessing TechniquesCreation VideoVideo codecsProduction TipsProcessing Techniques

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  • The Streaming Media ProcessProductionA/V Production, digitizing the raw media files, editingEncodingConverting to a streaming formatAuthoringConnecting the audience to your contentCreating an interface for your content Combining multiple data typesServingDistributing your content to the public

    SxSW Interactive Conference

  • Remember: Bandwidth is EverythingTypical bandwidths:dial-up: 37kbpsBroadband: ~2-300kbpsUncompressed audio = ~1400Kbps44.1Khz*16bits*2 channelsUncompressed NTSC video = ~30MBps720*480pixels*24bits*30frames/secondthats roughly 237,000bps, folks!We must reduce the data rate while maintaining fidelity

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  • How Codecs WorkCodecs use complex perceptual models to figure out what we perceive vs. what we hearAudioHear: 20 20,000Hz; over 120dB dynamic rangePerceive: Most sensitive in the midrange; loud sounds mask quiet soundsVideo See: full spectrum, 180 degree field of visionPerceive: Most sensitive to motion and colorCodecs use this info to determine what is most important; discard the restImportant to produce content with this in mind

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  • Audio Production TipsRemember: G-I-G-OUse good equipment and solid audio engineering practice Good equipment, microphone techniqueSet up a proper gain structureUse signal processing to optimize Compression and EQ can be used to optimize as needed

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  • Audio Production TipsUse good quality microphonesDirectional hand-held mics for reporting environmentsLavaliere mics for stationary talentShotgun microphone on a boom for location workDont forget your windsock(s) for outdoor workAvoid using the on-camera micUse balanced cables (XLR or TRS)Better signal level, more noise resistantUse Professional XLR adapter if necessary

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  • Production Tips - Location AudioLarge, quiet, isolated locations are bestNeed room to moveKeep noisy machinery away from microphonesSmall rooms sound smallTreat reflective surfacesHard flat surfaces reflect soundAcoustic foam, curtains, & tableclothsOutdoorsChallenges can be overcome

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  • Setting Up A Gain StructureMake sure each piece of equipment operates in its optimal rangeStart with first piece of equipment and work through the signal chainset the input and output gain for eachPeaks at -3dB for analog, -10dB for digital

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  • Signal Processing - CompressionRemember: Codecs assume loud signals are most importantCompression evens out audio levels Protects your equipment from spikes in audio levelAttenuating loud sections enables overall signal gainFattens audioHardware compressor is essential for live broadcasts

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  • How Compression worksSet a threshold, a ratio, and a post-compression gainStart with a threshold of 10db, 4:1 ratio, and set gain to match original signal levelVoice is much more compression tolerant than musicCompressionin action

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  • Signal Processing EqualizationEQ is turning up or down certain frequencies Ears are most sensitive to midrangeUse EQ to improve the tonal quality of your audioAdd sparkle, air, warmth, & presenceRemove rumble, hiss, clutter, harshnessHow?Find the right frequency, and turn the knob!Just like adjusting your car stereo or clock radio

    EQ example

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  • Useful EQ Frequencies

    EQ RangeContents2060 Hz Extreme low bass. Most speakers cannot reproduce this. 60250 Hz The audible low-end. Files with the right amount of low end sound warm, files without enough sound thin.250 Hz2 kHz The low-midrange. Files with too much in the low-mids are hard to listen to and sound telephone-like. 2 kHz4 kHz The high-midrange. Where most speech information resides. In fact, cutting here in the music and boosting around 3 kHz in your narration makes it more intelligible.4 kHz6 kHz The presence range. Provides clarity in both voice and musical instruments. Boosting 5 kHz can make your music or voiceover (not both!) seem closer to the listener. 6 kHz20 kHz The very high frequencies. Boosting here adds air but can also cause sibilance problems

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  • How Video Codecs WorkIntra-frame compressionJust like a .jpg or .png fileInter-frame compressionDifferences between frames are encodedKey framesEntire frame is encodedUses a lot of bandwidthDifference framesOnly differences are encodedUse relatively little bandwidth on low motion content

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  • Video Production TipsAvoid unnecessary motion/changesUse a tripod, use a tripod, use a tripodAvoid moving objects in the backgroundAvoid special effectsSimple edits are bestKeep the number of cuts to a minimumFramingSmaller screen, so frame tighter

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  • Video Production TipsG-I-G-OUse good video engineering practiceIf you dont know, hire someone Good equipment, proper techniqueIf you dont own it, rent itLighting is essentialNearly impossible to correct using softwareLow-light = no light

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  • Video Production TipsThe 3-point Lighting systemThe basis of virtually all lightingKey lightThe main light for the sceneGenerally 15 - 60 from cameraFill lightFills in the hard shadows of the key lightOn opposite side of camera from key lightBack lightSeparates the subject from the backgroundAbove & behind the subject

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  • Video Production TipsWhite balanceBest to set manuallyCamera filtersUV filters can make outdoor shoots less hazyFluorescent filters can make indoor office shoots look less anemicDiffusion filters can soften the image and make it look less harsh, more film-likeAmount of diffusion to use depends on your camerahttp://videosystems.com/ar/video_curse_digital_video/index.htm

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  • Digitizing VideoCapture cardsLow end fine for most streaming applicationsHigh end definitely provide better qualityFireWire (IEEE 1394, iLink)Enables direct digital video transferAvailable on most pro-sumer DV camcordersExternal FireWire devicesTake analog inputs (S-Video, composite) and convert to DV via FireWire5:1 compression, but very cost effective

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  • Video Processing TechniquesVGA vs. Television displaysVGA screens are far more detailed Traditional video tends to look dark & washed outAdjust BrightnessAdd gain to match screen to a TV monitorBe careful if youre going back out to the broadcast world!Adjust ContrastAdding a small amount is good; be careful thoughToo much contrast adds grain (bad for codecs)ColorIncreasing saturation a bit can be helpful

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  • Working With VideoBe sure to use the correct pixel aspect ratioTV pixels are slightly taller than wide; VGA pixels are squareTV resolution is approximately 720 x 480, but when displayed appears to be 4:3You must resize to a 4:3 aspect ratio if a VGA screen is your final destination640x480, 320x240, 240x180, etc.

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  • Streaming Media Production Best PracticesPart III Encoding

    Steve Mack, LUX Mediasmack@luxmedia.com

    SxSW Interactive Conference

  • EncodingRemember: Bandwidth is EverythingMake choices depending on audience bandwidthTotal bit rateAudio bits vs. video bitsOptimizing your encoding settingsAudiovideo

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  • Audio Encoding ChoicesTotal bit rate for audio8kbps - minimum16kbps good quality32kbps - FM quality64kbps CD qualityStereo vs. MonoMost program content is monoMono codecs have better fidelity Music can benefit from stereo encodingUse mono below 32kbps

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  • Audio Encoding ChoicesMusic vs. speech codecsSpeech has limited dynamic & frequency rangeSpeech sounds decent through a music codecMusic sounds horrible through a speech codecWhen in doubt, stick to a music codecWindows Media 9 Series has a new hybrid codec (cool!) butNot entirely backwards compatibleNew codec install available for legacy players, but not automatic must be installed

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  • Video - Encoding ChoicesAllot the correct amount for audioAudio tells the storyPeople will tolerate poor video with good audio the inverse is not trueChoose the right screen size (resolution)Codecs encode to whatever specifications you provideHigh action video content requires lower resolution; low action content can be largerRule of Thumb: Its better to reduce the resolution rather than the frame rateLess frames = more differences between framesMore differences = more to encode

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  • Video - Encoding ChoicesChoosing a Frame Rate / Frame QualityLess high quality frames, or more low quality frames?Limiting the frame rat...

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