Standard definition (480p) is good for standard-definition TV. If the video will play on a high-definition TV or display, choose one of the high-definition formats: 720p or 1080p. 4K is used for ultra-high-definition TVs and displays.
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720p (1280720 px; also called HD ready, standard HD or just HD) is a progressive HDTV signal format with 720 horizontal lines/1280 columns and an aspect ratio (AR) of 16:9, normally known as widescreen HDTV (1.78:1). All major HDTV broadcasting standards (such as SMPTE 292M) include a 720p format, which has a resolution of 1280720; however, there are other formats, including HDV Playback and AVCHD for camcorders, that use 720p images with the standard HDTV resolution. The frame rate is standards-dependent, and for conventional broadcasting appears in 50 progressive frames per second in former PAL/SECAM countries (Europe, Australia, others), and 59.94 frames per second in former NTSC countries (North America, Japan, Brazil, others).
The number 720 stands for the 720 horizontal scan lines of image display resolution (also known as 720 pixels of vertical resolution).[1] The p stands for progressive scan, i.e. non-interlaced. When broadcast at 60[note 1] frames per second, 720p features the highest temporal resolution possible under the ATSC and DVB standards. The term assumes a widescreen aspect ratio of 16:9, thus implying a resolution of 1280720 px (0.9 megapixels).
720i (720 lines interlaced) is an erroneous term found in numerous sources and publications. Typically, it is a typographical error in which the author is referring to the 720p HDTV format. However, in some cases it is incorrectly presented as an actual alternative format to 720p.[3] No proposed or existing broadcast standard permits 720 interlaced lines in a video frame at any frame rate.[4]
A 720p60 (720p at 59.94 Hz) video has advantage over 480i and 1080i60 (29.97/30 frame/s, 59.94/60 Hz) in that it comparably reduces the number of 3:2 artifacts introduced during transfer from 24 frame/s film. However, 576i and 1080i50 (25 frame/s, 50 Hz), which are common in Europe, generally do not suffer from pull down artifacts as film frames are simply played at 25 frames and the audio pitch corrected by 25/24. As a result, 720p60 is used for U.S. broadcasts while European HD broadcasts often use 1080i50 24* frame, with a horizontal resolution of 1920 or 1440 depending on bandwidth constraints. However, some European broadcasters do use the 720p50 format, such as German broadcasters ARD and ZDF, and the Norwegian Broadcasting Corporation (NRK). Arte, a dual-language French-German channel produced in collaboration by ARD, ZDF and France Télévisions, broadcasts in German at 720p50 but in French at 1080i50. The Flemish Broadcasting Company (VRT) in Belgium was using 720p50, but switched to 1080i50 a few years ago.[when?]
1080p (19201080 progressively displayed pixels; also known as Full HD or FHD, and BT.709) is a set of HDTV high-definition video modes characterized by 1,920 pixels displayed across the screen horizontally and 1,080 pixels down the screen vertically;[1] the p stands for progressive scan, i.e. non-interlaced. The term usually assumes a widescreen aspect ratio of 16:9, implying a resolution of 2.1 megapixels. It is often marketed as Full HD or FHD, to contrast 1080p with 720p resolution screens. Although 1080p is sometimes informally referred to as 2K, these terms reflect two distinct technical standards, with differences including resolution and aspect ratio.
1080p video signals are supported by ATSC standards in the United States and DVB standards in Europe. Applications of the 1080p standard include television broadcasts, Blu-ray Discs, smartphones, Internet content such as YouTube videos and Netflix TV shows and movies, consumer-grade televisions and projectors, computer monitors and video game consoles. Small camcorders, smartphones and digital cameras can capture still and moving images in 1080p resolution.
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.[citation needed] 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.[2][3][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.[4][5][needs update]
1080p50/p60 production format requires a whole new range of studio equipment including cameras, storage and editing systems,[6] 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).[4][5][7]
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.[9] 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 June 2016, EBU announced the "Advanced 1080p" format[11] which will include UHD Phase A features such as high-dynamic-range video (using PQ and HLG) at 10 and 12 bit color and BT.2020 color gamut, and optional HFR 100, 120/1.001 and 120 Hz; an advanced 1080p video stream can be encoded alongside baseline HDTV or UHDTV signal using Scalable HEVC. The ITU-T BT.2100 standard that includes Advanced 1080p video was subsequently published in July 2016.
In practice, 1080p typically refers to a 19201080 raster with a 16:9 picture aspect ratio. The following is a list of other resolutions with a picture height of 1080 lines that are sometimes referred as 1080p.[citation needed]
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.[citation needed]
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.[12] 2ff7e9595c
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