1080p

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1080p is the shorthand name for a category of video modes. The number 1080 represents 1,080 lines of vertical resolution,^[1] while the letter p stands for progressive scan or non-interlaced. 1080p is considered an HDTV video mode. The term usually assumes a widescreen aspect ratio of 16:9, implying a horizontal (display) resolution of 1920 dots across and a frame resolution of 1920 × 1080 or exactly 2,073,600 pixels. The frame rate in hertz can be either implied by the context or specified after the letter p (such as 1080p30, meaning 30 frames per second).

1080p is sometimes referred to in marketing materials as "True High-Definition" or "Full High-Definition". Although 2K/4K digital cinema technology is commercially available, and ultra-high definition video is in the research phase, 1080p and 1080i are currently the highest-resolution formats widely used for broadcasting and consumer distribution of video content.

Contents 1 Broadcasting standards 2 Production standards 3 Availability 3.1 1080i film-based content can become true 1080p/24 3.2 Broadcasts 3.3 Internet Content 3.4 Consumer televisions and projectors 3.5 Computer monitors 3.6 Storage format 3.7 Video games 4 Ability of the eye to see 1080p 5 See also 6 References 7 External links

[edit] Broadcasting standards

Due to bandwidth limitations of broadcast frequencies, the ATSC and DVB have standardized only the frame rates of 24, 25, and 30 frames per second (1080p24, 1080p25, 1080p30). 1080p30 is currently the most bandwidth-intensive video mode supported. If the standard MPEG-2 compression is used, versions with higher frame rate such as 1080p50 and 1080p60 could only be sent over higher-bandwidth channels; to send these over normal-bandwidth channels, a more advanced codec such as the H.264/MPEG-4 AVC codec must be used. Higher frame rates such as 1080p50 and 1080p60 are foreseen as the future broadcasting standard for production.^[2]

The ATSC is considering amending its standard to allow the incorporation of the newer codecs for optional usage like the DVB Consortium already has done with DVB-S2^{[citation needed]}. However, doing so is not expected to result in widespread consumer availability of broadcast 1080p programming, since most of the existing digital television sets or external digital receivers would still only be capable of decoding the older, less-efficient MPEG-2 codec, while the bandwidth limitations do not allow for broadcasting two simultaneous streams (i.e. both a 1080i or 720p MPEG-2 stream alongside a 1080p MPEG-4 stream) on the same broadcast channel.

[edit] Production standards

A new high-definition progressive scan format for picture creation is currently being developed to operate at 1080p at 50 or 60 frames per second.^[2][3] This format will require a whole new range of studio equipment including cameras, storage, edit and contribution links as it has doubled the data rate of current 50 or 60 field interlace 1920 × 1080 from 1.485 Gb/s to nominally 3 Gb/s. It is unable to be broadcast in a compressed transmission to current MPEG-2 based HD receivers. This format will improve final pictures because of the benefits of "oversampling" and removal of interlace artifacts.

[edit] Availability

[edit] 1080i film-based content can become true 1080p/24

The following examples refer to content that is encoded in progressive-scan form during recording or transmission—what would be considered "native" progressive signals. However, where 24 fps film-based material is concerned, a 1080i encoded/transmitted stream can become a true "1080p" signal during playback by deinterlacing to re-combine the split field pairs into progressive film-scanned frames. Regarding 24 fps film-source material presented in conventional 1080i60 form, the deinterlacing process that achieves this goal is usually referred to as "3:2 pulldown reversal" [also known as "inverse telecine"]. The importance of this is that, where film-based content is concerned, all 1080-interlaced signals are potentially 1080p signals given the proper deinterlacing. As long as no additional image-degradation steps were applied during signal mastering (such as excessive vertical-pass filtering), the image from a properly deinterlaced film-source 1080i signal and a native-encoded 1080p signal will look approximately the same. It should be noted that Blu-ray Disc and HD DVD sources are 1080p with no vertical filtering, therefore, 1080i output from players can be perfectly reconstructed to 1080p with 3:2 pulldown reversal.

As more and more processors and displays come to market able to apply 3:2 pulldown reversal to film-based 1080i60 signals, the amount of available "1080p" content for viewing expands (encompassing film-based 1080i60 feeds from broadcast HD, cable, and satellite).

[edit] Broadcasts

Various television networks in the world broadcast HDTV programming in 1080i and 720p; no 1080p broadcasting exists at this time. However, material that has been digitized from a 35-mm film source is basically 1080p/24, fit into 1080i/50 or 1080i/60 (progressive with segmented frames). With proper 3:2 reversal deinterlacing, it can be converted back into a true 1080p/24 signal (see above explanation).

[edit] Internet Content

There has been some content released in the 1080p format on the Internet. Some notable examples include the Apple QuickTime Trailers in HD 720p/1080p format, and the Microsoft WMV HD Content Showcase. Another example of 1080p content is the MacBreak 1080p podcast created by Leo Laporte and Alex Lindsay. This podcast is distributed via the bittorrent method of distribution because of the large file sizes resulting from the high bit-rates. All 1080p content currently (as of March 2007) distributed on the internet has frame rate of either 24, 25 or 30 frames per second, not the full frame rate of 50 or 60 FPS.

[edit] Consumer televisions and projectors

There is a growing selection of consumer televisions with native 1080p at this time. Among the television sets with a 1080p resolution, however, some are not capable of both accepting and reproducing a 1080p input signal, especially via a digital input such as Digital Visual Interface (DVI) or High-Definition Multimedia Interface (HDMI).^[4] Sony released VPL-VW100, a 1080p-resolution projector and Sony's 1080p Bravia sets can accept 1080p signals), while Mitsubishi released a 1080p rear-projection TV; both were based on LCoS technology and had limited availability. Several televisions in 2005 offered 1080p, including sets from Hewlett-Packard, Mitsubishi, Westinghouse Digital, Samsung and Sony. The 2006 Consumer Electronics Show (CES) introduced 1080p displays from most manufacturers, available in various display technologies. Also, 3:2 pulldown reversal (reverse telecine) for film-based 1080i60 signals is beginning to appear in some newer 1080p displays, which can produce a true 1080p quality image from film-based 1080i60 programs. Sanyo-Epson has announced a 7.1 inch 1920x1080 progressive television screen^[5].

[edit] Computer monitors

Cathode ray tube (CRT) computer monitors have long been capable of displaying (and exceeding) 1080p, albeit as a non-standard resolution since most CRT monitors have an aspect ratio of 4:3 (and those that are widescreen have a ratio of 16:10, not 16:9). Most 17-inch computer monitors which support 1280 × 1024 at 60 Hz will accept an input signal at 1920 × 1080 at 60 Hz, although the projected resolution will exceed the physical limitations of the display screen itself, which for CRT devices is commonly documented as phosphor dot pitch. Some modern widescreen liquid crystal display (LCD) monitors can also natively display 1080p content. Widescreen WUXGA monitors for example support 1920x1200 resolution, which can display a pixel for pixel reproduction of the 1080p (1920x1080) format. These resolutions are supported by several laptops with 15.4 and 17 inch displays. Additionally, many 24 inch widescreen LCD displays use 1920x1200 as their native resolution. Other 1080p-compatible LCDs, on the other hand, have lower than 1920x1080 native resolution and cannot display 1080p pixel for pixel. The output is resized; though it may not be noticeable to the viewer, what is seen is a slightly degraded version of the original image.

[edit] Storage format

1080p-encoded titles have been released on HD DVD and also Blu-ray Disc. The first generation of American/Japanese HD DVD players could only output the 1080p content via 1080i signal and required 3:2 pulldown deinterlacing in a display to reconstruct the original 1080p signal (see above for an explanation of why this does not lead to any difference between 1080i and 1080p in many cases). However, the second generation American/Japanese HD DVD players and the first generation of European HD DVD players (both launched in Q4-2006) support direct output of 1080p signal. Since the introduction of their first hardware generation, Blu-ray disc players have been able to output 1080p video (for example, the Samsung BD-P1000).*

As well as 1080p output, current HD DVD and Blu-ray Disc players both allow output of film-based material in conventional interlaced 1080i60 form, and 1080p displays that are able to apply 3:2 pulldown reversal can deinterlace film-based content and achieve full 1080p image quality.

1080p and near-1080p content has also been released on regular DVD-ROM disks using WMV HD compression. Although these titles could not be viewed for a while in normal DVD players, they can be played back by some current generation DVD Players (such as the Kiss DP-600), or on modern computers, given sufficient processing power and the right software.^[6]

• (The Samsung BD-P1000 converts 1080p content to 1080i and then back to 1080p again before sending the signal out through the HDMI output^[7])

[edit] Video games

Video games can also be rendered at 1080p. The video game consoles Sony PlayStation 3 and Xbox 360 support 1080p both for video content as well as for games.

[edit] Ability of the eye to see 1080p

A person's ability to distinguish small details is described by visual acuity. When individual pixels are barely resolvable, increased resolution brings no benefit for the viewer, unless the display can be brought closer. In order to see a benefit from 1080p content a display must be bigger than usual or the viewing distance needs to be closer than usual for normal television viewing. The ability of the eye to resolve 1080p content depends on the amount of contrast in the picture. For optimum viewing of resolution you need to sit back three times the viewing height ^{[8] [9]}. For example at nine feet away you need at least a 46 inch display to see a benefit from 1080p or for optimum viewing of resolution you need a 70 inch display.

[edit] See also

For a comparison between 1080p and 1080i, see the 1080i article.

• 1080i, 720p, 576p, 480p
• High-definition television (HDTV)

[edit] References

1. ^ Brian L. Clark. What’s this 1080p Stuff? March 13, 2006.
2. ^ ^{a b} EBU Recommendation FUTURE HIGH DEFINITION TELEVISION SYSTEMS on EBU
3. ^ EBU technical publication High Definition (HD) Image Formats for Television Production
4. ^ David Katzmaier. Can 1080p HDTVs handle 1080p sources? on cnet.com November 18, 2005.
5. ^ Sanyo-Epson announce 7.1-inch 1080p LCD: by far the world's smallest on Engadget.com 2006-10-17
6. ^ Microsoft. High Definition Quality with Windows Media Video 9. Accessed May 1, 2006.
7. ^ Samsung BD-P1000 Blu-ray Disc Player on soundandvisionmag.com
8. ^ [1]
9. ^ http://www.hdtvmagazine.com/articles/2006/07/in_the_eye_of_t.php

[edit] External links

• High Definition (HD) Image Formats for Television Production (EBU technical publication)
• Full HDTV
• More HDTV Displays Offering Native 1080p. January 8, 2005.
• 1080i vs. 1080p HDTV: should you care?. October 24, 2005.
• The Facts and Fiction of 1080p. April 17, 2006.
• [2] Pioneer PDP5000EX - World's first commercial 50 inch natively 1080p plasma screen
• HDTV Org Independent guide to High Definition TV
• The HDTV Progressive Frame Rate Clarification Initiative
• "Full-HD-ready, really?! Not definitive!" Report about HD-ready's requirements and their meaning, usage of the label and other similar marketing-slogans

Digital video resolutions

Designation	Usage examples	Definition (lines)	Rate (Hz)
			Interlaced (fields)	Progressive (frames)
Low; MP@LL	LDTV, VCD	240; 288 (SIF)		24, 30; 25
Standard; MP@ML	SDTV, SVCD, DVD, DV	480 (NTSC, PAL-M)	60	24, 30
		576 (PAL, SECAM)	50	25
Enhanced	EDTV	480; 576		60; 50
High; MP@HL	HDTV, HD DVD, Blu-ray Disc, HDV	720		24, 30, 60; 25, 50
		1080	50, 60	24, 30; 25
This table illustrates total horizontal and vertical pixel resolution via box size. It does not accurately reflect the screen shape (aspect ratio) of these formats, which is either 4:3 or 16:9.