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Hands on Guide to Webcasting. Streaming Media East. The Goal. Live at noon Audience participation yes, that means you. What We Have To Do. Planning programming production network infrastructure web presence Execution a/v production authoring encoding Testing everything – twice.
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Hands on Guide to Webcasting Streaming Media East
The Goal • Live at noon • Audience participation • yes, that means you
What We Have To Do • Planning • programming • production • network infrastructure • web presence • Execution • a/v production • authoring • encoding • Testing • everything – twice.
Rough Schedule • Initial discussion (10 mins) • Planning (1 hour) • basics (who/what/where/why) • Execution (1 hour) • a/v production setup • a/v testing • encoding setup • encoding testing
Why Webcasts are Tricky • They’re live • No second chance • Additional hardware requirements • Additional personnel requirements • They test the limits of your streaming infrastructure • Bandwidth • Server architecture (web & streaming) • They’re expensive and therefore can be hard to justify
First: Make the Business Case • Who • is the audience? • What • are we webcasting? • Where • is the location suitable • When • is there enough time to do it right? • Why • is this the best way to address the need?
We need a crew. • Executive Producer • Audio engineer • Videographer (camera op) • Encoding engineer • Host • Guest(s)
Planning • Location • Size, power, access, union fees • Signal Acquisition • On site connectivity, satellite • Equipment • Usually best to work with a partner • Crew • May come with equipment • Presentation • Talent, Pre/post show, technical difficulties • Network Infrastructure • host, bandwidth usage, encoding specs
Setup • Production area • Stage • Audio • Video • Encoding
Audio Setup • Avoid ground hum • Placement or extra equipment • Ambient mics • Absolutely for musical events • Tape down loose cables • Use compression • Test!
Setting Up A Gain Structure • Make sure each piece of equipment operates in its optimal range • Start with first piece of equipment and work through the signal chain • set the input and output gain for each • Peaks at -3dB for analog, -10dB for digital
Audio Production Tips • Compression “evens out” audio levels • Protects your equipment from “spikes” in level • Attenuating loud sections enables overall signal gain • “Fattens” audio • Hardware compressor is essential for webcasts
Video Setup • Tripods (heavy duty) • Risers if available • Lights • 3-point? • Flat wash? • White balancing (shading) • Test!
How Video Codecs Work • Intra-frame compression • Just like a .jpg or .png file • Inter-frame compression • Differences between frames are encoded • Key frames • Entire frame is encoded • Uses a lot of bandwidth • Difference frames • Only differences are encoded • Use relatively little bandwidth on low motion content
Video Production Tips • Avoid unnecessary motion/changes • Use a tripod, use a tripod, use a tripod • Avoid moving objects in the background • Avoid special effects • Simple edits are best • Keep the number of cuts to a minimum • Framing • Smaller screen, so frame tighter
Video Production Tips • G-I-G-O • Use good video engineering practice • If you don’t know, hire someone • Good equipment, proper technique • If you don’t own it, rent it • Lighting is essential • Nearly impossible to correct using software • Low-light = no light
Video Processing Techniques • VGA vs. Television displays • VGA screens are far more detailed • Traditional video tends to look dark & washed out • Adjust Brightness • Add gain to match screen to a TV monitor • Be careful if you’re going back out to the broadcast world! • Adjust Contrast • Adding a small amount is good; be careful though • Too much contrast adds grain (bad for codecs) • Color • Increasing saturation a bit can be helpful
Encoding Setup • Bit rate • Resolution • Capture card? • Encoding software? • Local Archive? • Push vs. pull encoding • Redundancy is key • Ideally redundant connectivity • Extra equipment • Multiple stream solutions
Authoring • Link to webcast page from home page • Always offer a metafile link • If embedding, keep it simple • Test!
Authoring • Problem: browsers don’t stream • Browsers don’t understand RTSP or MMS protocols • Browsers download entire file • Solution: metafiles • Small file delivered via HTTP • Contains information about streaming file 1 Web Server 2 4 3 Streaming Server 5
Authoring - Metafiles • QuickTime .qtl files • RealSystem .ram files • Windows Media .asx files <?xml version="1.0“ ?> <?quicktime type="application/x-quicktime-media-link“ ?> <embed src=“rtsp://your.qtserver.com/YourStream.mov" /> rtsp://your.realserver.com/YourStream.rm <asx version="3.0"> <entry> <ref href="mms://your.wmserver.com/YourStream.wmv" /> </entry> </asx>
Distribution Techniques • Redundancy is key • Robust load balancing required • Use multicast where appropriate • Usually best to work with a partner • TEST!
Distribution Methods • Unicast/multicast to servers • Unicast/multicast to local clients
Countdown • Test the audio • Test the video • Test the encoder(s) • Test the link(s) • Go live at least 10 minutes before event begins, preferably 30 minutes
Q & A Thank You Steve Mack smack@luxmedia.com