Consumers Experience

Transcript

Consumer Experience Steven A. Silva FOX NE&O HPA 2013 CONSUMERS EXPERIENCE THAT’S WHY WE ARE HERE! 1 Pre- DTV! Beautiful DTV! 2 DTV System          Analogue broadcasts ended on June 12, 2009 DTV has transformed our TV viewing experience Enabled broadcasters to offer HDTV with surround sound More programming choices via multicasting & interactive capabilities We still have the 19.3 Mb/s broadcast pipe! (6Mhz) DTV is made possible by compressing the video & audio Video compression via MPEG 2 & 4, JPEG2000, etc. Audio compression via Dolby AC-3 Video & audio are combined in an HD-SDI multiplexer DTV System 3 Analog Mono TV DTV Surround Sound 4 DTV AC-3 System          Surround sound at the advent of HDTV Not intended to mimic the audio processing of analog TV Ability to provide consistent loudness between programs Allows listeners to select different Dynamic Ranges (DR) AC-3 system has the capability for 6 channels (5.1) Left, right, center, LFE (the .1 channel) , Ls and Rs Low frequency enhancement (LFE) for 20 to 120 Hz 48 KHZ sampling rate and up to 128kbps per channel I.E. Fox's bit rate for surround sound is 448kbps 5.1 Markets       FOX Broadcasting & FOX Cable that originates from L.A. is in 5.1 31 HDTV (720p) channels with surround 9 SD channels with 2.0 FOX Houston broadcasts 31 channels in HDTV (720p) FOX, NBC, ABC/ESPN, Turner and CBS all broadcast in HDTV with 5.1 Smaller markets down mix the surround to 2.0 5 Real time downmix  Instead of manually performing a down mix, a real time down mixer box is employed by broadcasters  The downmixer automatically processes the signal to certain guidelines  Stereo  Lt/Rt  Low frequency enhancement is not used  The Dolby AC-3 stream has metadata values for the down mix Metadata Management is key for DTV AC-3 allows up to 28 metadata parameters which provide information, control and flexibility for the AC-3 stream classified into 3 groups: 1. Informational metadata- 7 optional parameters which describe encoded audio 2. Basic control metadata- 19 parameters which determine dynamic range, compression, downmixing, matrix decoding & filtering 3. Critical control metadata- 2 parameters critical for proper encoding and decoding.  Channel mode: proper channel formatting for decoder (i.e. 1-6 channels)  Dialog level: dialnorm i.e. -24  Default values mostly used for other metadata parameters 6 Dynamic Range Management      AC-3 is not intended to mimic analog TV’s limited dynamic range! AC-3 is capable of broadcasting a very wide dynamic range AC-3 eliminates or minimizes traditional compression/limiting Provides producers with greater freedom to convey their artistic intent Allows listeners to have DR choices, with exceptions Dynamic Range Management  Works via gain words in the AC-3 encoder which provide a “reversible” approach during decoding, allowing users to select a desirable dynamic range within their equipment and viewing environment  Dynamic Range Control (DRC) modifies the program by reducing very loud portions and raising very low levels with reference to the dialnorm  But can only be effective with an accurate dialnorm!  Home system users can use DRC on or in the off mode for the full dynamic range 7 AC-3 DRC AC-3 DRC  AC-3 encoder calculates gain words for selected DR profiles  Choice of the compression profile is up to the program producer  5 profiles: Music light, Music standard, Film light (Fox NE&O), Film standard & Speech  “None” choice, inhibits the generation of DRC control words & DRC functionality  None choice can be problematic due to being irreversible!  Decoders have 2 required main “modes”, line and RF  Listener has options from the AC-3 stream  Loudness normalization is always applied 8 AC-3 DRC DRC profiles 9 Too LOUD!! Fox Experience           Began 10 yrs ago with issues concerning loud commercials in FB games Loudness communication issues Can’t with ppm & vu meters or a tape with 1k tone Large quantity of LM 100’s available with LeqA Automated our LM100’s for start, stop & record What is the anchor point? Dialogue centric? Do we measure just the center channel? Other combos? What about dynamic range issues and silent periods? D/I challenges. What other meters have DI? QC ing at ingest and satellite returns 10 Fox Experience         QC ing at ingest & satellite returns Leq A’s plots closely mirror LKS & are generally ½ to 1½ dB greater Finally decided to measure 5.0 Measure programs and interstitials as segments in infinite mode Developed Fox “gating” Dialogue intelligence (DI) off If specs were followed we probably wouldn’t be here! LOUDNESS will never be perfect but the annoyances are being reduced! 11 Thank You DTV Education      HUGE priority at Fox and is greatly needed in the broadcast realm. Audio/Video education will minimize problems And it’s FREE!! DTV Audio Group via SVG Loudness online tutorial, released in 2011 & RP A/85 is online In production on a “Surround Mixing” on line tutorial, which will be released this year  3 E’s, Educate, evaluate, and enforce! 12 Thank You 13