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Audio For PBS BROADCAST. Lip Sync Loudness 5.1 Surround. Lip Sync. Why errors are hard to detect Why they happen What to do. 1 - Errors Below Threshold. NETA Quality Workshop. Scenario Show: -1 frame, looks OK Station: -1 frame, looks OK Broadcast show: -2 frames, looks bad
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Audio For PBS BROADCAST Lip Sync Loudness 5.1 Surround
Lip Sync Why errors are hard to detect Why they happen What to do
1 - Errors Below Threshold NETA Quality Workshop • Scenario • Show: -1 frame, looks OK • Station: -1 frame, looks OK • Broadcast show: -2 frames, looks bad • Solution: All sync must becorrect (not just look it)
2 - Errors That Cancel NETA Quality Workshop • Scenario • Show: -3 frames • Station: +3 frames • Broadcast show: 0 frames, looks good • But two wrongs don’t make a right! • Good shows will look bad on this station! • Solution: All sync must becorrect
3 - Errors That Drift NETA Quality Workshop • Scenario • Broadcast now: Good • Broadcast later: Bad • Solution: Be careful! Change channels! • Millions of commercial and consumer MPEG decoders drift!
4 - Error Perception That Drifts NETA Quality Workshop • Scenario • Sync now: looks Good • Same sync later: Bad • Solution: Patience • Need tight shots of people talking • Some people talk out of sync! • Stare at sync long enough, you will start seeing things!
Station Production Tips NETA Quality Workshop • Delay audio with every video delay • Framesyncs • Switcher effects • LCD & plasma displays! • Don’t trust your ears • TEST!
Station Master Control Tips NETA Quality Workshop • Align sync at every point • Framesyncs & processors • MPEG & ATSC encoder settings • Surprises • Don’t trust your ears • TEST!
Test Tools NETA Quality Workshop • Edit Suites and QC Stations • syncheck.com • Station Master Control • ID with 1 frame dot and beep, then non-linear editor • Normal programming with Miranda or Evertz solutions
Consumer Tips NETA Quality Workshop • LCD & Plasma TV's • Internal decoder should be OK • Separate decoder & audio systems require offset! • MPEG decoders • Try changing channels
TV Loudness Why it started out bad How it got better What to do Impact of CALM act
Industry Progress • Early Confusion • Subsequent Conflict & Loudness Wars • Recent Consensus: ATSC A85! • www.atsc.org/cms/standards/a_85-2009.pdf NETA Quality Workshop
CALM Act • Passed Sept 29, 2010 • Requires FCC to establish rule by Sept 29, 2011: • Applies to all stations, cable and other MVPDs • “Commercial” loudness must comply with ATSC A85 • Installing “Complaint” processing will satisfy FCC • Two 1-year waivers allowed for hardship NETA Quality Workshop
CALM Act Questions for PTV • What is a “Commercial”? • Are funder credits, promos and ID’s included? • What is the measurement interval? • The duration of the “spot”, or shorter? • Can we maintain program dynamics? • Tightly control submissions and avoid processing? NETA Quality Workshop
Production Tips NETA Quality Workshop • Buy an LKFS meter (BS.1770) • Your mix engineers will like it! • No money? • Dialog peaks at -10 dBFS works pretty well • Produce content to -24 LKFS • Average over entire show, ± 2 dB • Dramatic moments can still be ±10 dB!
Station Tips NETA Quality Workshop Set plant for unity gain Set encoder dialnorm to -24 Get an LKFS meter (BS.1770) Measure day-long compliance with -24 LKFS Apply processing if needed Compare local stations and share
5.1 Surround Submission Broadcast
5.1 Surround Submission • PBS Requirement deferred beyond 2011 • Upmix • Insure compatible downmix - demand from your vendor! • 5.1 Production • Insure compatible downmix - demand from your engineer! • Traditionally all dialog in C only • Calibrate your LFE NETA Quality Workshop
5.1 Surround Broadcast NETA Quality Workshop • Increasing Demand • Consumers are building theaters • PBS will be supplying more content • For PCM, decoder needed for every IRD • NGIS NRT eliminates this expense • Compelling 5.1 shows will arrive early via NRT
PCM Plant - SAP on 7/8 NETA Quality Workshop
PCM Plant - SAP on 3/4 NETA Quality Workshop