Progressive segmented Frame (PsF) is a High Definition mastering video format used to store progressive content on interlaced media. Unlike broadcast video formats, PsF is not intended for direct delivery to end users. PsF was designed as a unified world-wide standard to simplify the process of converting cinematic content to the various video standards, and as means for video exchange between the networks and broadcasters worldwide.[1]
With PsF, a progressive frame is separated into "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 common electronic circuitry that is used to store, process and route interlaced video. The primary difference between PsF and interlaced video is motion. In PsF there is no motion between the two segments that make up the "progressive" frame while in interlaced there is typically motion between the "fields". The signal is played back at 1080i but when viewed, it is seen as true 1080p
PsF and 2:2 pulldown
Progressive segmented frame technique is equivalent to 2:2 pulldown pattern. "PsF" seems to be a term used in production, while "2:2 pulldown" is a term used for broadcast.
Charles Poynton, an authority in digital television, makes 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] He does not question the usefulness of progressive segmented frame to deliver progressive material for the end users; just one paragraph above he explains the technique to transfer movies to video: "Film is transferred to 575i video using 2:2 pulldown: Each film frame is scanned into two video fields (or frames); the film is run 4% fast."
PsF is not an alternative to Telecine 2:3 pulldown. Telecine 2:3 pulldown is a method of converting 23.976PsF to 59.94i for broadcast in NTSC.
Sony's CineAlta series of cameras are capable of recording directly to 23.976PsF, 24PsF and 25PsF on HDCAM tape along with the interlaced versions of those signals.