Progressive segmented Frame (PsF, sF, SF)

Progressive segmented frame
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Progressive segmented Frame (PsF, sF, SF) is a High Definition mastering video format designed to acquire, store, modify and distribute progressive content using interlaced equipment and media.
Contents[hide]
1 History
2 24PsF and 23PsF
3 25PsF
4 30PsF and 29PsF
5 References
6 Bibliography
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[edit] History
PsF has been designed to simplify the conversion of cinematic content to different video standards, and as means of video exchange between networks and broadcasters worldwide.[1] Brought to life by the movie industry in the end of 1990s, the original PsF specification was focused on 24 frame/s content. Existing interlaced equipment had to be modified for 48 Hz scanning rate in order to work properly with PsF video.
With PsF, a progressive frame is sliced into two "segments", with the odd lines in one segment and the even lines in the other segment. This allows for a progressive picture to be processed through the same electronic circuitry that is used to store, process and route interlaced video. Technically, progressive segments are equivalent to interlaced fields, but unlike native interlaced video, there is no motion between the two fields that make up the video frame, both fields represent the same instant in time.
PsF technique is similar to 2:2 pulldown, which is widely used in 50 Hz television systems to broadcast 25 frame/s progressive material, but is rarely employed in 60 Hz systems as there is very little content of progressive 30 frame/s material. 2:2 pulldown scheme had originally been designed for interlaced devices, so fine vertical details are usually filtered out to minimize interlaced line twitter. PsF has no such filtering.
Not everyone welcomed the PsF standard. Some industry observers maintained that native 24p processing would have been a better and cleaner choice. Charles Poynton, an authority in digital television, made the following remark in his book: "Proponents of [PsF] scheme claim compatibility with interlaced processing and recording equipment, a dubious objective in my view."[2] William F. Schreiber, former Director of the Advanced Television Research Program at MIT, suspected that the continued advocacy of interlaced equipment originated from consumer electronics companies that were trying to get back the substantial investments they had made in obsolete technology.[3]
Despite the criticism, PsF quickly became a de-facto standard for high quality film-to-video transfer. One of the documented examples of PsF usage is the 2003 transfer of the film "Terminator 2" to DVD, performed by Artisan and THX. The original 24 frame/s movie was converted to PsF format and recorded to HD-D5 videotapes. This allowed for the creation of a digital master that was nearly identical to the original film, and made it possible to edit digitally at the native frame rate.[4] The same digital master appears to be used for the 2006 Blu-ray Disc transfer of the movie.[5]
PsF became a means of initial image acquisition in professional Sony video cameras. It is employed in HDCAM and XDCAM video cameras, including the HDW-F900 CineAlta camera which was used by George Lucas for creating Star Wars, Episode 2, and by Alexander Sokurov for creating Russian Ark fully in the digital domain.
PsF has been recognized by Recommendation ITU-R BT.709 as a legitimate way to transport progressive frames within an interlaced system. 25PsF and 30PsF rates have been added to the specification in addition to the more established 24PsF. "Fractional" frame rates, having the above values divided by 1.001, are also permitted, which results in 23.98PsF and 29.97PsF rates, currently used in 60 Hz systems.

[edit] 24PsF and 23PsF
24PsF (48sF, 1080sf24, 1920x1080/24/1:1SF) is the original PsF format, which is used in professional equipment for film-to-video transfer, for high definition mastering and for video exchange between networks. This may be the first universal video standard which transcends continental boundaries, an area previously reserved for film.[6]
23PsF (1080sf23, 1920x1080/23.98/1:1SF) frame rate is often used for HD production in organizations that also produce standard definition 525 line services (i.e. at 59.94Hz).[7]

[edit] 25PsF
25PsF (1080sf25, 1920x1080/25/1:1SF) is used in 50Hz systems for production that originates on video and is targeted for television distribution.

[edit] 30PsF and 29PsF
30PsF (30p, 1080sf30, 1920x1080/30/1:1SF) and 29PsF (1080sf29, 1920x1080/29.97/1:1SF) are sometimes used in 60Hz systems for sitcoms and music shows.
At present time, neither 30PsF nor 29PsF are well suited for television distribution, because few TV sets are capable of proper deinterlacing of such video.

[edit] References
^ "Jim Mendrala, A discussion of 24p frame and the new 48sF frame format". http://www.tech-notes.tv/Jim/Articles/24vs48sF.html.
^ "Charles Poynton, Digital Video and HDTV: Algorithms and Interfaces". http://books.google.com/books?id=ra1lcAwgvq4C&pg=RA1-PA62&sig=8ZAl0RqzUYnyxQSmjxiIw4ZJDbE.
^ "The history and politics of DTV". http://www.cinemasource.com/articles/hist_politics_dtv.pdf.
^ "Terminator 2: Extreme Edition". http://www.dtvforum.info/lofiversion/index.php/t16581.html.
^ "Terminator 2: Judgment Day (Blu-ray)". http://bluray.highdefdigest.com/terminator2.html.
^ "Steve Wiedemann, 24/P HDTV: The Fall of Film Production". http://www.filmmaking-careers.com/film-production.html.
^ "pro-bel, Vistek HD Poster". http://www.pro-bel.com/site_documents/Vistek_HD_Poster.pdf.

[edit] Bibliography
What is 24P?"