1080p is the shorthand name for a category
of video modes. The number 1080 represents 1,080 lines of
vertical resolution, 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.
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).
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.
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.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.
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. 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.
Availability
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).
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).
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 Showcasewhich offers non-standard 1440x1080p clips.
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.
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). 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.
Computer monitors
Cathode ray tube (CRT) computer monitors have long been capable
of displaying (and exceeding) 1080p. However, 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), one would need a monitor
with enough range in the vertical sizing control in order
to squeeze the raster to a 16:9 aspect ratio so as to properly
display a 1080p source. Most 17-inch computer monitors which
support 1280 × 1024 at 60 Hz will accept an input signal
at 1920 × 1080 at 60 Hz. This is because CRT circuitry
only place hard limits on the scanline rate (i.e. vertical
resolution) and not on the actual bandwidth of the video signal
itself (i.e. horizontal resolution). In practice, the ability
of the viewer to resolve adjacent pixels (which affects perceived
image sharpness) on a CRT will highly depend on the dot pitch
(basically, how much adjacent pixels overlap) as well as the
high-bandwidth roll-off of the monitor circuitry. Relatively
inexpensive CRT monitors (such as a consumer grade 17")
will likely not have the dot pitch necessary to fully resolve
adjacent pixels of a 1080p image. Nevertheless, due to the
inherent design of the CRT display itself, all pixels will
always occupy the correct locations onscreen even if adjacent
pixels show significant overlap.
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.
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.
The Samsung BD-P1000 converts 1080p content to 1080i and
then back to 1080p again before sending the signal out through
the HDMI output
Video games
Video games can also be rendered at 1080p. The video game
consoles Sony PlayStation 3 and Xbox 360 are capable of displaying
1080p both for video content as well as for games. The PlayStation
3 has a built-in Blu-ray Disc player, allowing it to play
Blu-Ray discs. An add-on HD-DVD player can be purchased for
the Xbox 360.
Many modern computer games can run at 1080p or higher.
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 viewing distance can be shortened. For normal television
viewing distances, 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. 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 a maximum
of approximately three times the viewing height. For example
at nine feet (2,75 m) away you need at least a 46 inch (115
cm) display to see a benefit from 1080p or for optimum viewing
of the resolution you need a 70 inch (175 cm) display.
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