Прогрессивная сегментированная кадровая развертка (PsF) и ее применение.

Scheme to handle progressive scan video using interlaced equipment
Progressive segmented Frame (PsF, sF, SF) is a scheme designed to acquire, store, modify, and distribute progressive scan video using interlaced equipment. With PsF, a progressive frame is divided into two segments, with the odd lines in one segment and the even lines in the other segment. Technically, the 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. This technique allows for a progressive picture to be processed through the same electronic circuitry that is used to store, process and route interlaced video. The term progressive segmented frame is used predominantly in relation to high definition video. In the world of standard definition video, which traditionally has been using interlaced scanning, it is also known as quasi interlace, progressive recording or movie mode. Other names for PsF used by electronic equipment manufacturers include progressive recording (Sony), progressive scan mode (Sony), progressive shutter mode (Sony), frame shutter mode (Sony), frame mode (Panasonic and Canon), Digital Cinema (Panasonic), Pro Cinema (Panasonic) and Cinema mode (Canon).

PsF was designed to simplify the conversion of cinematic content to different video standards, and as a means of video exchange between networks and broadcasters worldwide. Brought to life by the movie industry in the end of the 1990s, the original PsF specification was focused on 24 frame/s content resulting in existing interlaced equipment having to be modified for 48 Hz scanning rate in order to work properly with 24 frame/s content. Not everyone welcomed the PsF standard, however. 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."

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: Judgment Day" to DVD, performed by Artisan Entertainment 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. The same digital master appears to be used for the 2006 Blu ray Disc transfer of the movie. 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; the resulting 23.976PsF and 29.97PsF rates are used in 59.94 Hz systems. No change from 59.94 Hz systems to 60 Hz (although provided for and anticipated) has occurred allowing display on analog NTSC color televisions and monitors after down conversion and encoding. 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.

2:2 pulldown is widely used in 50 Hz interlaced television systems to broadcast progressive material recorded at 25 frame/s, but is rarely used in 60 Hz systems. The 2:2 pulldown scheme had originally been designed for interlaced displays, so fine vertical details are usually filtered out to minimize interline twitter. PsF has been designed for transporting progressive content and therefore does not employ such filtering.

24PsF (48sF, 1080sf24, 1920×1080/24/1:1SF) 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. 25PsF (1080sf25, 1920×1080/25/1:1SF) is used in 50 Hz systems for production that originates on video and is targeted for television distribution. 29.97PsF (1080sf29, 1920×1080/29.97/1:1SF) formats are sometimes used in 60 Hz systems for sitcoms and music shows. 29.97PsF as well as 30PsF (30p, 1080sf30, 1920×1080/30/1:1SF) formats are gaining popularity as an acquisition format for Web video delivery, because most video hosting web sites cannot stream video with rates higher than 30 frame/s.