Audio For PBS BROADCAST
description
Transcript of Audio For PBS BROADCAST
QG
Lip Sync Loudness 5.1 Surround
QG
Lip Sync Why errors are hard to detect Why they happen What to do
QG
1 - Errors Below Threshold Scenario
Show: -1 frame, looks OKStation: -1 frame, looks OKBroadcast show: -2 frames, looks bad
Solution: All sync must be correct (not just look it)
NETA Quality Workshop
QG
2 - Errors That Cancel Scenario
Show: -3 framesStation: +3 framesBroadcast 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 be correct
NETA Quality Workshop
QG
3 - Errors That Drift Scenario
Broadcast now: GoodBroadcast later: Bad
Solution: Be careful! Change channels! Millions of commercial and consumer MPEG
decoders drift!
NETA Quality Workshop
QG
4 - Error Perception That Drifts Scenario
Sync now: looks GoodSame sync later: Bad
Solution: PatienceNeed tight shots of people talking Some people talk out of sync!Stare at sync long enough, you will start seeing things!
NETA Quality Workshop
QG
Station Production Tips Delay audio with every video delay
FramesyncsSwitcher effectsLCD & plasma displays!Don’t trust your earsTEST!
NETA Quality Workshop
QG
Station Master Control Tips Align sync at every point
Framesyncs & processorsMPEG & ATSC encoder settingsSurprisesDon’t trust your earsTEST!
NETA Quality Workshop
QG
Test Tools Edit Suites and QC Stations
syncheck.com
Station Master ControlID with 1 frame dot and beep, then non-linear editorNormal programming with Miranda or Evertz solutions
NETA Quality Workshop
QG
Consumer Tips LCD & Plasma TV's
Internal decoder should be OKSeparate decoder & audio systems require offset!
MPEG decoders Try changing channels
NETA Quality Workshop
QG
TV Loudness Why it started out bad How it got better What to do Impact of CALM act
QG
Industry Progress Early Confusion Subsequent Conflict & Loudness Wars Recent Consensus: ATSC A85!
www.atsc.org/cms/standards/a_85-2009.pdf
NETA Quality Workshop
QG
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 A85Installing “Complaint” processing will satisfy FCCTwo 1-year waivers allowed for hardship
NETA Quality Workshop
QG
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
QG
Production Tips 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 LKFSAverage over entire show, ± 2 dBDramatic moments can still be ±10 dB!
NETA Quality Workshop
QG
Station Tips 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
NETA Quality Workshop
QG
Tolerance
QG
5.1 Surround Submission Broadcast
QG
5.1 Surround Submission PBS Requirement deferred beyond 2011 Upmix
Insure compatible downmix - demand from your vendor!
5.1 ProductionInsure compatible downmix - demand from your engineer!Traditionally all dialog in C onlyCalibrate your LFE
NETA Quality Workshop
QG
5.1 Surround Broadcast Increasing Demand
Consumers are building theatersPBS 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
NETA Quality Workshop
QG
PCM Plant - SAP on 7/8
NETA Quality Workshop
QG
PCM Plant - SAP on 3/4
NETA Quality Workshop