Broadcast Video Formats

Below is a list of broadcast video formats.
  • 24p is a progressive scan format and is now widely adopted by those planning on transferring a video signal to film. Film and video makers use 24p even if they are not going to transfer their productions to film, simply because of the on-screen "look" of the (low) frame rate, which matches native film. When transferred to NTSC television, the rate is effectively slowed to 23.976 FPS (24×1000÷1001 to be exact), and when transferred to PAL or SECAM it is sped up to 25 FPS. 35 mm movie cameras use a standard exposure rate of 24 FPS, though many cameras offer rates of 23.976 FPS for NTSC television and 25 FPS for PAL/SECAM. The 24 FPS rate became the standard for sound motion pictures in the mid-1920s. Practically all hand-drawn animation is designed to be played at 24 FPS. Actually hand-drawing 24 unique frames per second ("1's") is costly. Even in big budget films, usually hand-drawn animation is done shooting on "2's" (one hand-drawn frame is shown twice, so only 12 unique frames per second) and some animation is even drawn on "4's" (one hand-drawn frame is shown four times, so only six unique frames per second).
  • 25p is a progressive format and runs 25 progressive frames per second. This frame rate derives from the PAL television standard of 50i (or 50 interlaced fields per second). Film and television companies use this rate in 50 Hz regions for direct compatibility with television field and frame rates. Conversion for 60 Hz countries is enabled by doing 2:2:3:2:3 pulldown. This is similar to 2:3 pulldown, and the result looks identical to a typical film transfer. While 25p captures half the temporal resolution or motion that normal 50i PAL registers, it yields a higher vertical spatial resolution per frame. Like 24p, 25p is often used to achieve "cine"-look, albeit with virtually the same motion artifacts. It is also better suited to progressive-scan output (e.g., on LCD displays, computer monitors and projectors) because the interlacing is absent.
  • 29.97p previously was the format that American television broadcasts used to be most commonly displayed at, as specified by SMPTE 294M.[citation needed] This was the standard format of American TVs due to the displaying of CRT screens which were common place before the wide spread use of digital monitors. Alternating currents are used to time each scan, by which two scans are performed per frame due to interlacing of the display. The NTSC method implemented in the display of televisions bandwidth of the frequency requires an odd integer multiple of the horizontal frequency divided into two separate interlacing parallel line patterns. The Horizontal frequency was 15,750. This format was the solution caused by the problem of 30 Frames per second is not able to output to the even integer by the odd integer multiple. Each conducted scan equals 262.5 rows on the television set with interlacing totaling 525 rows. Before 1953 the entire frequency band of the TV was divided between black and white image and sound, but after the introduction of color broadcasting to widespread commercial use, more information was needed to provide for the color. The space between each frequency on the band was dedicated as to not cause electromagnetic interference between the picture and the sound. 6 MHz is dedicated to each analog broadcasting station. 1.5 MHz of which is unusable due to the electromagnetic interference gap between frequencies. This format fell out of use because of the introduction of digital broadcasting and online streaming.
  • 30p is a progressive format and produces video at 30 frames per second. Progressive (noninterlaced) scanning mimics a film camera's frame-by-frame image capture. The effects of inter-frame judder are less noticeable than 24p yet retains a cinematic-like appearance. Shooting video in 30p mode gives no interlace artifacts but can introduce judder on image movement and on some camera pans. The widescreen film process Todd-AO used this frame rate in 1954–1956.
  • 48p is a progressive format and that is being trialled in the film industry. At twice the traditional rate of 24p, this frame rate attempts to reduce motion blur and flicker found in films. Director James Cameron stated his intention to film the two sequels to his film Avatar higher than 24 frames per second to add a heightened sense of reality. The first film to be filmed at 48 FPS was The Hobbit: An Unexpected Journey, a decision made by its director Peter Jackson. At a preview screening at CinemaCon, the audience's reaction was mixed after being shown some of the film's footage at 48p, with some arguing that the feel of the footage was too lifelike (thus breaking the suspension of disbelief).
  • 50i is an interlaced format and is the standard video field rate per second for PAL and SECAM television.
  • 60i is an interlaced format and is the standard video field rate per second for NTSC television (e.g., in the US), whether from a broadcast signal, DVD, or home camcorder. This interlaced field rate was developed separately by Farnsworth and Zworykin in 1934, and was part of the NTSC television standards mandated by the FCC in 1941. When NTSC color was introduced in 1953, the older rate of 60 fields per second was reduced by a factor of 1000/1001 to avoid interference between the chroma subcarrier and the broadcast sound carrier. (Hence the usual designation "29.97 FPS" = 30 frames (60 fields)/1.001)
  • 59.94p is the frame rate used for 720p broadcast HDTV, as specified in SMPTE 296M.
  • 50p/60p is a progressive format and is used in high-end HDTV systems. While it is not technically part of the ATSC or DVB broadcast standards yet, reports suggest that higher progressive frame rates will be a feature of the next-generation high-definition television broadcast standards. In Europe, the EBU considers 1080p50 the next step future proof system for TV broadcasts and is encouraging broadcasters to upgrade their equipment for the future.Many modern cameras can shoot video at 50p and 60p in various resolutions. YouTube allowed users to upload videos at 60 FPS in June 2014. YouTube also allowed full HFR videos previously uploaded before 2014.
  • 72p is a progressive format and is currently in experimental stages. Major institutions such as Snell have demonstrated 720p72 pictures as a result of earlier analogue experiments, where 768 line television at 75 FPS looked subjectively better than 1150 line 50 FPS progressive pictures with higher shutter speeds available (and a corresponding lower data rate). Modern cameras such as the Red One can use this frame rate to produce slow motion replays at 24 FPS. Douglas Trumbull, who undertook experiments with different frame rates that led to the Showscan film format, found that emotional impact peaked at 72 FPS for viewers.
  • 100p / 119.88p / 120p are progressive-scan formats standardized for UHDTV by the ITU-R BT.2020 recommendation.

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