Progressive Segmented Frame

Progressive segmented Frame (PsF, sF, SF) is a scheme designed to acquire, store, modify, and distribute progressive-scan video using interlaced equipment and media.

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 PsF technique is similar to 2:2 pulldown, which is widely used in 50 Hz 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.

The term progressive segmented frame is used predominantly in relation to high definition video. In the world of standard definition video, which traditionally have been using interlaced scanning, it is also known as quasi-interlace or progressive recording.