1080i (also known as Full HD or BT.709) is a combination of frame resolution and scan type. 1080i is used in high-definition television (HDTV) and high-definition video. The number "1080" refers to the number of horizontal lines on the screen. The "i" is an abbreviation for "interlaced"; this indicates that only the even lines, then the odd lines of each frame (each image called a video field) are drawn alternately, so that only half the number of actual image frames are used to produce video. A related display resolution is 1080p, which also has 1080 lines of resolution; the "p" refers to progressive scan, which indicates that the lines of resolution for each frame are "drawn" on the screen in sequence.
Within the designation "1080i", the i stands for interlaced scan. A frame of 1080i video consists of two sequential fields of 1920 horizontal and 540 vertical pixels. The first field consists of all even-numbered TV lines and the second all odd numbered lines. Consequently, the horizontal lines of pixels in each field are captured and displayed with a one-line vertical gap between them, so the lines of the next field can be interlaced between them, resulting in 1080 total lines.
1080i differs from 1080p, where the p stands for progressive scan, where all lines in a frame are captured at the same time. In native or pure 1080i, the two fields of a frame correspond to different instants (points in time), so motion portrayal is good (50 or 60 motion phases/second). This is true for interlaced video in general and can be easily observed in still images taken of fast motion scenes. However, when 1080p material is captured at 25 or 30 frames/second, it is converted to 1080i at 50 or 60 fields/second, respectively, for processing or broadcasting. In this situation both fields in a frame do correspond to the same instant. The field-to-instant relation is somewhat more complex for the case of 1080p at 24 frames/second converted to 1080i at 60 fields/second; see telecine.
Any screen device that advertises 1080p typically refers to the ability to accept 1080p signals in native resolution format, which means there are a true 1920 pixels in width and 1080 pixels in height, and the display is not over-scanning, under-scanning, or reinterpreting the signal to a lower resolution. The HD ready 1080p logo program, by DIGITALEUROPE, requires that certified TV sets support 1080p 24 fps, 1080p 25 fps, 1080p 50 fps, and 1080p 60 fps formats, among other requirements, with fps meaning frames per second. For live broadcast applications, a high-definition progressive scan format operating at 1080p at 50 or 60 frames per second is currently being evaluated as a future standard for moving picture acquisition. Although 24 frames per second is used for shooting the movies.[needs update] EBU has been endorsing 1080p50 as a future-proof production format because it improves resolution and requires no deinterlacing, allows broadcasting of standard 1080i50 and 720p50 signal alongside 1080p50 even in the current infrastructure and is compatible with DCI distribution formats.[needs update]
1080p50/p60 production format requires a whole new range of studio equipment including cameras, storage and editing systems, and contribution links (such as Dual-link HD-SDI and 3G-SDI) as it has doubled the data rate of current 50 or 60 fields interlaced 1920x1080 from 1.485 Gbit/s to nominally 3 Gbit/s using uncompressed RGB encoding. Most current revisions of SMPTE 372M, SMPTE 424M and EBU Tech 3299 require YCbCr color space and 4:2:2 chroma subsampling for transmitting 1080p50 (nominally 2.08 Gbit/s) and 1080p60 signal. Studies from 2009 show that for digital broadcasts compressed with H.264/AVC, transmission bandwidth savings of interlaced video over fully progressive video are minimal even when using twice the frame rate; i.e., 1080p50 signal (50 progressive frames per second) actually produces the same bit rate as 1080i50 signal (25 interlaced frames or 50 sub-fields per second).
In the United States, the original ATSC standards for HDTV supported 1080p video, but only at the frame rates of 23.976, 24, 25, 29.97 and 30 frames per second (colloquially known as 1080p24, 1080p25 and 1080p30). In July 2008, the ATSC standards were amended to include H.264/MPEG-4 AVC compression and 1080p at 50, 59.94 and 60 frames per second (1080p50 and 1080p60). Such frame rates require H.264/AVC High Profile Level 4.2, while standard HDTV frame rates only require Level 4.0. This update is not expected to result in widespread availability of 1080p60 programming, since most of the existing digital receivers in use would only be able to decode the older, less-efficient MPEG-2 codec, and because there is a limited amount of bandwidth for subchannels.
EBU requires that legacy MPEG-4 AVC decoders should avoid crashing in the presence of SVC or 1080p50 (and higher resolution) packets. SVC enables forward compatibility with 1080p50 and 1080p60 broadcasting for older MPEG-4 AVC receivers, so they will only recognize baseline SVC stream coded at a lower resolution or frame rate (such as 720p60 or 1080i60) and will gracefully ignore additional packets, while newer hardware will be able to decode full-resolution signal (such as 1080p60).
In the United States, 1080p over-the-air broadcasts are currently available in select stations in some cities in the US via ATSC 3.0 multiplex stations where as ATSC 3.0 is currently rolling out throughout the U.S. The majority of the stations that broadcast at 1080p are CBS and NBC stations and affiliates. All other stations do not broadcast at 1080p and usually broadcast at 720p60 (including when simulcasting in ATSC 3.0) or 1080i60 (outside of ATSC 3.0) encoded with MPEG-2. There is also technical restrictions with ATSC 3.0 multiplex stations that prevent stations from airing at 1080p. While converting to ATSC 3.0 is voluntary by TV Stations, there is no word when any of the major networks will consider airing at 1080p in the foreseeable future on a national scale, although they are required to broadcast ATSC signals for at least five years thereafter. However, satellite services (e.g., DirecTV, XstreamHD and Dish Network) utilize the 1080p/24-30 format with MPEG-4 AVC/H.264 encoding for pay-per-view movies that are downloaded in advance via satellite or on-demand via broadband. At this time, no pay service channel such as USA, HDNET, etc. nor premium movie channel such as HBO, etc., stream their services live to their distributors (MVPD) in this format because many MVPDs, especially DBS and cable, do not have sufficient bandwidth to provide the format streaming live to their subscribers without negatively impacting their current services.
For material that originates from a progressive scanned 24 frame/s source (such as film), MPEG-2 lets the video be coded as 1080p24, irrespective of the final output format. These progressively-coded frames are tagged with metadata (literally, fields of the PICTURE header) instructing a decoder how to perform a 3:2 pulldown to interlace them. While the formal output of the MPEG-2 decoding process from such stations is 1080i60, the actual content is coded as 1080p24 and can be viewed as such (using a process known as inverse telecine) since no information is lost even when the broadcaster performs the 3:2 pulldown.
Blu-ray Discs are able to hold 1080p HD content, and most movies released on Blu-ray Disc produce a full 1080p HD picture when the player is connected to a 1080p HDTV via an HDMI cable. The Blu-ray Disc video specification allows encoding of 1080p23.976, 1080p24, 1080i50, and 1080i59.94. Generally this type of video runs at 30 to 40 megabits per second, compared to the 3.5 megabits per second for conventional standard definition broadcasts.
As of 2012, most consumer televisions being sold provide 1080p inputs, mainly via HDMI, and support full high-definition resolutions. 1080p resolution is available in all types of television, including plasma, LCD, DLP front and rear projection and LCD projection. For displaying film-based 1080i60 signals, a scheme called 3:2 pulldown reversal (reverse telecine) is beginning to appear in some newer 1080p displays, which can produce a true 1080p quality image from film-based 1080i60 programs. Similarly, 25fps content broadcast at 1080i50 may be deinterlaced to 1080p content with no loss of quality or resolution.
Sony has their first and formerly VAIO 1080p laptop, VPCCB17FG, in 2011, and since Asus also has their first 4K laptop GL502 which was formerly branded Republic of Gamers in 2017, 1080p has also become the nowadays lowest standard for laptops.
@Syed_Mairaj can you state why you. Why do you need 1080i in the first place ? I am curious to know. As @Rose_Power-Wowza_Com mentioned it does not do well for the digital media of these days. However if you absolute must and you can live with delay you can try experimenting using ffmpeg to go from deinterlaced to interlaced.
Adding the local TV channels was a simple affair, and it easily tuned in all 25+ digital channels and sub-channels which are being broadcast from towers atop the Empire State Building, about 2 miles away. I noticed no break-up or pixilation of the image on the HD channels, and the low bandwidth digital sub-channels looked no worse than usual. The rest of the set-up was simply plugging in an HDMI cable for 1080i and 1080p sources, a component video cable, to test upconversion of 480i sources and an S-video cable with left/right analog to see how VHS tapes looked (better than one might expect, actually).
On the 1080i test, with the HDTV set to its "Dot By Dot" mode, the set showed that it can effectively de-interlace both film-sourced and video-sourced 1080i material to 1080p detecting an inherent 3:2 cadence in the film material and reconstructing single-pixel high rows of a moving test patterns without excessive stuttering. To pass the "Film" test, however, I did have to disable the TV's "Text Optimization" feature (under "PureCinema"), otherwise the low boxes of the 1080i/p test pattern strobed. On the HD jaggies test, the set availed itself equally well, showing that the set's diagonal processor is top notch. 2b1af7f3a8