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The free lunch: progressive-scan at the same bit rate? (or how I learned to love 1080p/60)

The free lunch: progressive-scan at the same bit rate? (or how I learned to love 1080p/60). David Wood and Hans Hoffmann European Broadcasting Union. Where’s the deep magic?. The compressed bit needed for 1080p/60 is the same or less than for 1080i/60.

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The free lunch: progressive-scan at the same bit rate? (or how I learned to love 1080p/60)

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  1. The free lunch: progressive-scan at the same bit rate? (or how I learned to love 1080p/60) David Wood and Hans Hoffmann European Broadcasting Union

  2. Where’s the deep magic? • The compressed bit needed for 1080p/60 is the same or less than for 1080i/60. • Original scenes always exist in ‘whole pictures’ • Interlacing is a form of compression (drop alternate lines with field offset). • Interlacing is a ‘systematic’ compression system (same whatever the contents of the scene). • Hybrid MC DCT is a ‘content adaptive’ compression. • Interlacing is the New England Patriots. • Hybrid MC DCT/Wavelet is the New York Giants. • You know who should win.

  3. Where’s the deep magic? • An interlaced system combines TWO stages of compression: first interlacing, then hybrid MC DCT. • A progressive system just uses hybrid MC DCT for the total process. • The hybrid MC DCT (redundancy extraction) ‘replaces’ the interlacing. • We replace a ‘systematic system’ with a ‘content adaptive’ system. • The content adaptive system is ‘bound to win’. • The progressive system will always be equal to or better than an interlaced system on average. • Interlace needs half the bit rate of a progressive system only because it already half compressed.

  4. That was yesterday.... • Interlacing was a brilliant idea in the 1930s. • We used interlaced scanning because it was a simple way to reduce bit rate by 50% when we had no other ways. • We used interlaced scanning because it was a good match to the way a CRT works. • Which of the above apply now?

  5. Idealised spectrum bounderies...for rapid look.

  6. Production, Contribution, distribution. Where does 1080p/60 fit today?

  7. 1 2 3 4 5 6 7 8 9 Playing the new ‘Chutes and Ladders’ MEDIA - SERVICES LINEAR (audio-visual mat) NON LINEAR (audio-visual mat) MULTIMEDIA/SOCIAL (data, text, pictures, interact) SHARED (lean backward) PERSONAL (lean forward) MEDIA - CONTEXT • Media companies • need to be active on all platforms: • Different services • Different networks • Different devices MOBILE (on the move)

  8. 1 2 3 4 5 6 7 8 9 Growth in quality of experience MEDIA - SERVICES LINEAR (audio-visual mat) NON LINEAR (audio-visual mat) MULTIMEDIA/SOCIAL (data, text, pictures, interact) NEED FOR INCREASED QUALITY “Beyond HD” SHARED (lean backward) PERSONAL (lean forward) MEDIA - CONTEXT MOBILE (on the move)

  9. The staircase to production quality heaven... 8k (16 x 1080p) 8k Ultra HDTV Progressive Higher Frame rates Larger colour range. 3DTV Multiview 4k (4x1080p) Immersive Quality Transition to 1080p/50 (full HD) 4k UHDTV Progressive Larger colour range. 3DTV Two normal HDTV images Transition SDTV to HDTV HD Master Format 1080p/50 Progressive S3D Two normal HDTV images Legacy HDTV 1080i/25 & 720p50 S3D two ½ HD images Transition analogue to digital DIGITAL Standard TV 625 –lines 1990s 2004 2011 ….2016…. …202x

  10. What happens to quality?

  11. 1080i/30(interlaced) 720p/60(progressive) 1920 1280 1080 720 1.5 Gbit/s 1.5 Gbit/s 1080p/60(progressive) 1920 Nominal static resolution 1920x1080 60 frame progressive 1080 1080p/60... 3 Gbit/s

  12. Master format: easy to derive 720p/60 and 1080i/30 Higher image quality headroom Multi-genre production 3G-SDI enables 1080p/50 in production and 3D applications (two normal HD signals) Studio compression systems for 1080p/50 on the market Why 1080p/60 production ?

  13. AVID DNxHD 4:2:2 10 bit 1080p/50(progressive) 1920 Panasonic AVC-Intra 200 4:2:2 10 bit 1080 3 Gbit/s interface SONY HDCAM-SR HDCAM-SR lite 4:2:2 10 bit EBU Tests on studio compression systems for 1080p/50 • Conducted in a project between EBU and industry • Multigeneration testing 365 Mbit/sec 160.4 GByte/hour 454.6 Mbit/sec 199.77 GByte/hour 734 Mbit/sec322,5 GByte/hour 367 Mbit/sec 161.2 GByte/hour Graphic Massimo Visca, RAI

  14. Shooting test sequences in 1080p/50 State of the art equipment • Zeiss Master Prime Lens • Sony F35 Camera • Uncompressed storage YUV10 • 2 DVS systems with dual link • Sony reference display 23” LCD • Skilled team (NRK+ others)

  15. Viewers from more than 10 EBU members Dolby 42” PRM-4200 Professional Reference Monitor (1920 x 1080 LCD monitor with LED backlighting). • Expert Viewing at IRT (1°- 3° March 2011)

  16. Full Quality HDTV Library Snell Alchemist converter 1080p/50 to 1080i/25 1080p/50 to 720p/50

  17. Expert viewing - Results in a nutshell • Different encoders provide different performance but, on average, the encoders demonstrated a performance which is nearly transparent to the original even up to the 7th generation. • The tested codecs (1080p/50, 1080i/25, 720p/50) meet the EBU requirements for image quality. • Different encoders provide different quality headroom. • Target applications today: high budget productions. • Conclusion: • High quality 1080p/50 production tools are available

  18. The Results • The BPN reports

  19. Step 2: 1080p50 in an End to End Chain • Demonstration at IBC 2011 • Live chain including 1080p/50 camera, 2 hops--contribution codecs and distribution encoder, prototype set-top box • Simulations a 1080i/25 chain was set up using the same bit-rates • Image quality comparison on two Dolby reference Monitors

  20. IBC 2011 experiment with live 1080p/50 chain • Live 1080p/50 from Frankfurt to Geneva to Amsterdam

  21. Towards a single HD production master format:1080p/50 • Live 1080p/50 from Frankfurt to Geneva to Amsterdam

  22. Results of the experiment • A end to end 1080p/50 chain is feasible with today’s equipment • Same distribution bit rate as 1080i/25 with better image quality (main benefit is sharpness stays in motion) • Is mainstream production possible? • If manufacturers would reduce prices, yes • But not all editing systems support 1080p/50 yet • In distribution? • Systems such as DVB support 1080p/50 • Many home display with HDMI 1.3 can show 1080p/50 • New set-top boxes/receivers with support of H.264 Level 4.1 would be required

  23. 1080i/25(interlaced) 720p/50(progressive) 1920 1280 1080 720 HDTV today • Quality in the home • Larger size display make artefacts more visible • Displays are all progressive – low cost up-converters for interlaced HD • UHDTV displays set to appear in the home • Alternative content (download, Games) better than broadcasts? • Consequently: need for better image delivery format ?

  24. Is the difference big enough between 1080i/25 and 1080p/50? • Is the difference visible in the home? • On a small display (up to 42”) – likely not • With larger displays, or displays up converting to 4K UHDTV displays – very likely YES • In production to have a future proof master: YES

  25. 4k Display What about an intermediate chain….? We would be curious in such an subjective comparission experiment: 1080@p50 With H.264 14 Mbps production chain 4k@p50 8k@p60 Or 4k@p60 4k@p50 with HEVC X Mbps

  26. Overall conclusion • 1080p/60 may be the best production option for 720p/60 and 1080i/30 delivery • Uses ‘3G’ production infrastructures • Many broadcasters are wisely “1080p/50 ready” • There is no 4K infrastructure available yet • Still high prices, not yet ‘mainstream’ • Production bit-rates 200…400 Mbit/s • Best master format for the next few years until 4K UHDTV is feasible • In the home, 1080p60 may be an option for some services - many consumer displays and some receivers can handle 1080p60 • 1080p/50 in distribution could also help a 4k production and home environment.

  27. Thank you for listening! • Further questions contact: hoffmann@ebu.ch and wood@ebu.ch Acknowledgements • EBU Codec group of SP HIPS many members and industry • Massimo Visca, RAI (also for some slides) • Jens Fischer (Master Student), IBC demo • Many others……..

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