The
Television Broadcast community is moving from Standard to Wide
Screen television. Conversion
from the NTSC television aspect ratio of 4X3 to the Wide Screen
ratio of 16X9 is inevitable.
Professionals in the Large Screen Video Display (LSVD)
industry need to understand all aspects of this transition to
plan wisely for the conversion of their own systems.
This paper explores and presents key areas that should be
considered by LSVD professionals when transitioning to Wide Screen
operation. It
provides the information needed to make informed artistically
based technology decisions on what equipment to purchase for the
smoothest transition to Wide Screen operation.
LSVD
professionals are asking many questions about the new wide screen
format. Do I need to
upgrade my facility to a wide screen display? What are the
advantages and disadvantages of the wide screen format?
What areas need to be reviewed and addressed to make my
transition proceed smoothly?
What new equipment will I need?
What currently owned equipment can be utilized with the
wide screen format? Will
I be able to run programming from my archives in the wide screen
format? What is happening in the broadcasting community regarding
wide screen displays and HDTV and how does this affect me?
When do I need to be up and running with wide screen
displays to keep current and profitable?
These are some of
the key questions that LSVD professionals are asking regarding
wide screen technology. These
questions and more are answered and addressed below.
The overwhelming
majority of Large Screen Video Displays in North America, be they
JumboTrons, Diamond Visions, Astrovisions, or LEDs are constructed
with a standard television aspect ratio. While they vary in size and resolution they all, with two
notable exceptions, have a width to height ratio of 4X3 or very
close to 4X3.
Because of the
resolution limitations of every large screen display technology,
standard definition (NTSC) signals have two to nine times greater
picture resolution than current LSVD screens can reproduce.
Unfortunately, the twelve times improvement in resolution,
offered by High Definition Television over standard analog
television, is wasted in the Large Screen Display environment.
Even if current large screen displays could reproduce high
definition television, the resolving ability of the human eye, at
typical event viewing distances, limits the perceived picture
detail.
Therefore, for
the purposes of this discussion, we will examine the impact of
Wide Screen aspect ratios, not the absolute resolution or detail
quality of the presented image.
On December 24,
1996 the Federal Communications Committee (FCC) issued the
technical standard for digital television and high-definition
television (SDTV & HDTV).
On April 3, 1997 the FCC issued the final table of digital
channel assignments for free over-the-air television to the
general public. The
Broadcast community has the following mandated time frame:
 |
The four major
networks (ABC, NBC, CBS, & FOX) will have their top
ten market stations on the air with DTV by May 1, 1999. |
 |
Six months
later, the 11th through 30th markets
of the same networks must be on the air with digital TV. |
 |
By the year 2006
the current NTSC analog television service will terminate
and that spectrum be reclaimed for reassignment. |
It is clear that
the Broadcast Community has its marching orders.
ABC, NBC, & FOX have voluntarily pledged to be on the
air in digital by November 1,1998, however the end date for NTSC,
2006, may only see an 85% digital implementation by broadcasters.
Despite these
real world milestone variances, it is clear that the digital train
is rolling.
HDTV has an
aspect ratio of 16X9 and SDTV has a choice of aspect ratios, 16X9
or 4X3. To the casual
observer, Wide Screen (16X9) is synonymous with High Definition
Television, and High Definition is synonymous with Digital.
While they are related, due to industry and regulatory
standards, it is possible to have analog High Definition
Television, as in Japan, and Wide Screen presentations can be made
on standard definition (NTSC) television, using letterbox
techniques. These
differences are important to note, to avoid potential confusion
when discussing wide screen technologies
What does the FCC
mandate mean to the Large Screen Display Industry?
Wide screen Television presentations to the in-home general
public are inevitable. That
same public, viewing their favorite TV shows at home, will want
and will expect wide screen presentations as part of their
out-of-home experience, just as they have come to expect the
replay, scoring, and statistical information they now get.
Wide screen sportscasting also needs to be considered. A
number of sports facilities have had mobile digital production
rigs pull up to their truck dock.
Are wide screen sports teleproductions far behind?
The FCCs 1996
SDTV / HDTV document allows for 18 variations of resolution and
aspect ratio within the standard. Determination of aspect ratio now becomes a programming /
production issue not the limitation of the transport medium.
Aspect ratio is
the issue and it is essentially independent of technology.
Yes, each technology is predicated on a given aspect ratio,
but its possible to alter the aspect ratio of any film or
television technique from the ratio implicit in that technique.
- Aspect Ratio
Accommodation
A wide screen show can be produced using conventional analog NTSC
4X3 equipment. Conversely,
a 4X3 presentation can be produced on a CinemaScope screen. At a minimum, all that is needed is to frame the original
material in the same way that a camera shot is framed.
If the wings (sides) or borders (top & bottom) have no
information they can be black or cropped.
In a movie theater curtains are moved to mask the unused
portion of the frame. In
television masking with drapes isnt possible so we see the
black borders during letterbox reduction of feature films.
- Pan and Scan
When transferring from wide screen feature film to conventional
television, there is another transfer option - pan & scan.
Since the television image is narrower, the motion picture
image needs to be cropped to fit the TV frame.
Information is lost in the process.
Gradual panning or rapid repositioning (cutting) between
frames insures that the key action areas of the wide screen
material are seen within the narrower frame.
It is easy to understand that this technique is filled with
compromises and continues to be a hot issue with the production
community. As far
back as silent movies, directors and cinematographers such as
Westerberg, Eisenstein and Griffith have argued the artistic and
production merits of the cropping process and its impact to
picture content.
The cable based
Bravo, Arts & Entertainment, and American Movie Classics
channels do both letter boxing and pan & scan every day, in
fact the same movie has been aired in each technique at different
times of the day.
Management of
aspect ratio becomes a significant production issue.
It is entirely possible for sports broadcasts to be
originated as multiple channels of 4X3-aspect ratio, progressive
scanned, Standard Definition (digital) Television within the 1996
FCC standard. Its
also possible to air a feature motion picture as a single channel,
16X9-aspect ratio, interlace scanned, High Definition (digital)
Television presentation without changing any of the transmission,
or receiving equipment used for the broadcast.
The
expectation of the fan and government mandates on broadcasters are
compelling LSVD facilities to install 16X9 screens in their
scoreboard structures.
In
the short term, providing the viewer / fan a wide screen
presentation gives them something they cant experience at home.
In the long term it will match the fans in-home experience.
Below
is a brief overview of the options available for upgrading to a
16X9 screen.
WIDE SCREEN 16 X 9
CONSTRUCTION
To achieve the wide screen aspect ratio, a 4X3 screen can have
additional display units added to each side to widen it out from
12X9 to 16X9. As an
example, a 32 X 24 foot screen, with a 4X3 (12X9) aspect ratio, is
made up of display units that are stacked 36 high by 18 wide. The
screen can be built out to 16X9 by adding 6 columns of display
units 36 high or 3 columns of units to each side.
The new screen now becomes 36 units high by 24 units wide.
While
this works for new construction, additional issues, such as
picture element matching have to be considered when doing any 16X9
retrofit additions to existing screens.
The number of hours any screen has operated will determine
the maximum brightness the board can produce.
Adding new picture elements for the wing(s) means that the
older part of the screen cant be as bright as the new wing(s). Even if the brightness of the new elements can be adjusted to
match, issues of color balance may remain.
In some cases, it may be better to replace the entire
screen than to add on units.
Widening the
display screen is only part of the challenge, all be it a
significant one. There
are a number of options available for screen enlargement. Further details will be left to other papers.
Current 4X3
Screens
Outdoor screen sizes range from a nominal 22X16 feet to
40X30 feed and are typically either 26X20 or 32X24 feet in
size. Indoor screen sizes range from 10X7 feet to
16X12 feet with the typical size being 12X9. Some
"indoor" screens have been used outdoors with a
size of up to 24X18 feet.
A 32X24 foot screen
actually has a viewable area of 31.23' by 23.43', made up
of stacked display units, with framing elements that bring
the screen out to its nominal rated size. The actual
display units each have a 4X3 aspect ratio giving the
overall screen the familiar television look. |
Once the wide
screen is in place, what is shown on it?
 |
How is all the
archive 4X3 material already in the can presented on
a new 16X9 Wide Screen? |
 |
When legacy 4X3
material is played back on the wide screen, what about the
unused 4X9-picture area? |
 |
Use reverse
letterboxing, or stretch the image? |
 |
How are live
camera shots framed to get the most impact from the
screens panorama while getting the viewer as close as
possible to the action? |
PRODUCTION AFTER THE WIDE SCREEN
IS INSTALLED
- Existing
Material
There is a considerable amount of material in LSVD archive
libraries. The vast
majority of it, if not all of it, is 4X3 sized film or tape.
Several options for converting wide screen pictures into
the 4X3 format have been discussed.
However, conversion from 4X3 to 16X9, while maintaining
picture content, does not fill the wide screen.
The equivalent of a 4X9 picture area ends up unused, and
because the existing program content doesnt fill out the wide
screen, the image appears smaller.
- Filling
Out the Wings POP
Filling out these unused wings is the challenge.
Stretching the 4X3 picture distorts the human form and any
added graphics. If
the aspect ratio is left alone, the archive 4X3 picture can be
center positioned & reverse letterboxed, to create two 2X9
wings with a 12X9 center. If
the archive program is justified all the way to the left or right
edge, the two 2X9 wings become one 4X9 wing.
By
creating and filling that 4X9 wing, a Polyscreen Display or
POP - Picture Out of Picture is created.
Presenting two images on the same screen is multicasting,
and that mode provides several possibilities, frankly
opportunities. The reclaimed 4X9 area is essentially a narrow
portrait style display, or it can be configured as three 4X3
pictures stacked one on top of the other.
Stills, graphics, clips and animation can be placed in what
was wasted area.
With
proper sizing, framing, positioning, and scaling the source
material and with the addition of select pieces of video
equipment, an electronic signboard or auxiliary scoreboard
operating simultaneously with the archive presentation is
possible. (Please
note that image, logo and font sizes have to be carefully
considered when programming these polyscreen wing(s) due to
the inherent resolution limitations of the large screen
technologies.
-
Live Shots Shoot and Protect
Live camera shots present a different challenge.
The first issue is panorama vs. close-ups.
The second issue is saving 16X9 shots back to the
traditional 4X3 aspect ratio for archive and distribution.
Both wide screen and conventional aspect ratios need to be
accommodated at the same time.
Plus shots need to be framed to insure maximum height
(size) of the action covered.
The technique called shoot and protect is used to do
accomplish both goals.
During
production, the captured image is framed to make the live action
look correct in a smaller 4X3 frame while a larger area is
protected to allow images to be seen in the 16X9 frame without
unwanted edges, equipment, or activity becoming visible in the
wider shot. The safe
action area becomes the 4X3 frame, and it can be defined by
putting reticle marks on the camera viewfinders and monitor wall
monitors. That inner
safe area is termed the reticle region and the outer frame is
called the aperture region. The
area between reticle and aperture, where significant action is to
be avoided, has been labeled fluff.
Shoot
and Protect techniques allow facilities to accommodate both wide
and standard aspect ratios. In
the short term, it insures that images shot now will play in the
4X3 world, and in the long term it insures that the images shot
today will be compatible when wide screen presentations are the
norm. Shoot and
Protect allows action shots to be framed as tall as possible,
utilizing the full height of the screen.
The determination of what is primary action and what is
fluff and how they are framed for the different aspect ratio
systems, is in reality an artistic / production decision.
PRODUCTION
SOLUTIONS
Shoot & Protect and Picture Out of Picture techniques
hopefully will put to rest many production questions raised by the
Large Screen Display Industry during its migration to wide screen.
Ok,
so weve got production options and wide screen material can be
sized to fit within the existing screen creating the familiar
letterbox presentation. Why
not stay in the 4X3 analog world and add the minimum equipment
needed for letterbox and Picture Out of Picture presentation?
CREATE
WIDE SCREEN ON A 4X3 SCREEN WITHOUT UPGRADING
Most
Large Screen Video Display front-end control rooms in the United
States and Canada are equipped with analog NTSC television
equipment. At a minimum, all that is needed to present wide screen
source material is to size down the material to fit within the
width of the existing 4X3 screen.
Although the height of the active screen is reduced thus
creating the familiar letterbox presentation, it will work.
But does this option meet the needs of the viewers?
THE VIEWERS PERSPECTIVE
The goal of the Large Screen Video Display, in the out-of-home
setting is:
 |
To enhance the
in-game / event experience. |
 |
To provide the
viewer / fan with information and entertainment he or she
cant get from their seat. |
 |
To get the
viewer / fan more involved in the action by using replays,
statistics, highlights, close-ups, and contests. |
The
at-home viewer is relatively close to the screen, sitting at a
distance six to ten times picture height.
Whereas, the stadium viewer is often seated at a distance
25 to 50 times the screen height.
No question that the larger the screen the happier everyone
is, and the larger the screen the more easily each fan can see the
presentation. Dont
forget that a larger screen image is perceived as a better image! Large font graphics and close-up framing are the order of the
day.
BRING THE FAN CLOSER vs.
PANORAMA
So theres the dilemma: The broadcast industry is headed to
the wide screen panorama experience, while the Large Screen
presenters goal is to enhance the in-game / event experience by
involving the fan and bringing him or her closer to the action.
To maintain impact, Large Screen Display heights need to be
maintained or enhanced as the screen widens from 4X3 (12X9) to
16X9
Staying
with a 4x3 screen using letterboxing may be a short-term answer
but it is not a long-term solution.
To stay current, screens will need to be updated to the
wide screen 16x9 format for the long term.
CURRENT 4x3 FRONT END CONTROL
ROOMS
While many large screen production facilities have purchased
digital postproduction editing equipment, and a few control rooms
have been built with three wire component analog video technology,
almost all Large Screen Video Display front-end control rooms in
the United States and Canada are equipped with analog, composite,
4X3 aspect ratio, NTSC television equipment.
Control rooms are being designed with digital equipment
interconnected by the serial digital interface SDI standard, but
one can count the number in operation on one hand.
STAY IN ANALOG? OR CONVERT TO
DIGITAL
Remember those digital trucks pulling up to the dock?
The broadcast community has to go digital by the end of the
decade. At minimum, their on air transmission equipment will be
upgraded to digital, and it makes sense that their studio and
remote equipment will be also be upgraded.
The broadcast industry is standardizing on a digital signal
stream. It wont be long before the signals available from those
production trucks, such as camera-ISO and switcher program will
only be available in the digital format.
Like it
or not technology marches on.
Two-inch quad machines are gone, one-inch helical machines
are gone, tube cameras are gone, and analog synchronizers are
gone. It wont be
too long before our old friend analog NTSC is also gone. At least one major manufacturer has announced that all of its
analog products have been discontinued.
Very soon Television equipment will only be talking digital.
LEAST DISRUPTIVE MIGRATION PATH
This may be the point for some to panic so hang on. There
is a migration path, and it doesnt have to be enormously
disruptive. Good
planning with careful resource allocation are key elements of this
solution.
When
beginning any facility construction or upgrade, you must look in
the near term (one to three years) and in the long term (over
three years). Where
is the LSVD industry going in the next five years? DIGITAL!
EXISTING
CONTROL ROOMS
To modify an existing analog control rooms for wide screen
presentations is definitely possible, and may be appropriate for
the short term. The
following are the minimum equipment additions needed to pull off
the adaptation.
MINIMUM ADDITIONS
- Multicasting
The production solutions presented earlier section suggest
that, when presenting 4X3 material on the new 16X9 screen, the
wings need to be filled out.
To do that, multicasting is needed.
The main picture channel needs to be combined with,
additional picture channels. The screen becomes a composite
layering, or Polyscreen Display of the archive 12X9 picture
and the 4X9-wing image.
- Additional Sources
To generate two picture elements, additional still storage,
graphics, and moving image playback equipment is needed.
-
Format Layering
Some method is needed to interleave those two pictures.
A compositing generator is needed to provide the
Picture Out of Picture presentation. When shoot and protect camera signals are displayed, the
generator has to crop the live signal into the 16X9 aspect ratio
of the new screen. When
4X3-legacy material is displayed, the generator has to layer the
separate filler information to one side and behind the
standard ratio image.
The generator
essentially places the legacy image over and to one side of
the wing image. Pre-production of the wing picture elements can be
done with conventional 4X3 aspect ratio analog equipment. Of
course the covered portion of the wing background need not have
any useable content since it will never be seen on the screen.
- Truck
Interface
Before the digital production trucks start pulling up to your
door, digital to analog interface equipment will need to be
installed for the analog control room to handle those digital
signals.
Your
existing analog plant can have aspect ratio accommodating
equipment bandaged together on a piece by piece basis in order to
keep up with the Jones.
That however should only be considered a short-term
solution.
BUILD NEW WITH ANALOG
So the legacy control room has gone as far as it can.
The war horse has given its all.
What happens next? Purchase new analog equipment for the control room or buy
digital equipment? That
is the dilemma. Plus,
is the newly purchased analog equipment really analog?
COMPATIBLE EQUIPMENT DIGITAL
ISLANDS
- FS, CG, SS, DVE, & File
Server
As video production equipment evolves, it moves to digital.
Right now, the inner workings of all new Frame
Synchronizers, Character Generators, Still Stores, Digital Video
Effects and most File Servers (VideoDisk Recorders) are digital.
When you replace one of these devices today, the new units come
standard with digital ins and outs.
In many instances options have to be purchased to convert
the machine to analog NTSC.
-
Tape Recorders
The next generation of video tape recorders are digital, be it
D1, D5, Digital BetaCam, BetaCam SX, DVCPRO, or DVCAM. Yes you can
buy analog recorders, but who wants to when the digital machines
give so much more quality at the same or lower price.
Plus, more and more TV stations and production houses are
transferring programs on digital tape.
-
Editors Linear or Non-Linear?
Purchasing an editor system inevitably raises the issue of
Linear vs. Non-Linear? The editor purchase decision should be based on the ease and
efficiency of operation, not on the type of technology used.
Either of the two editor choices can be used successfully in the
wide screen environment.
Random Vs.
Sequential Editing
Non-Linear editing is essentially random access, hard disk
based, and digital.
Linear editing is
essentially sequential; magnetic tape based, and can use
either analog or digital recording equipment.
Random access editing
offers very quick determination of the Edit Decision List,
and compilation of the final product. What slows the
whole process down is that most Non-Linear systems do not
have removable media. There is a wait for the
finished product to transfer to an archive media such as
tape.
Sequential editing forces
editors to wait the search times of linear tape during
construction, but the storage media can be instantly
removed when the editing process is complete. The
edit controller is a digital (computer) device. The
tape storage system can be analog or digital.
Here again technology is
providing the best of both worlds. If videodisk
recorders are added to an existing editing system, the
edit preview and assembly speed of random access is
gained. IF source machines are disk based and the
session is mastered to tape, both the speed of hard disk
and the removeability and transportability of tape are
acquired. This doesn't replace the multitude of
software advantages available with full blown Non-Linear
systems, but it does maximally use the installed equipment
base. |
OLDER TECHNOLOGY
- Switchers, Routers, and
Monitors
Whats left? Analog
video mix effects switchers (vision mixers), routing switchers and
monitors are still available.
This core analog video equipment and its analog
interconnections: patch bays, distribution amplifiers, and cable,
can currently be purchased at lower cost than their digital
counterpart.
All
those digital islands can be configured with analog
inter-connections. In
fact a new analog system purchased today is really a group
of digital islands connected together in an analog way.
When
looking three years and beyond, those digital islands need
to be interconnected in the digital domain.
To do that, the switchers, routers, monitors, distribution
amplifiers, and any other analog orphans have to become
digital.
BUILD ALL DIGITAL
When building or rebuilding the Front-End plant, the least
disruptive migration path for the long term is to plan and install
a complete digital system with all equipment interconnected in the
digital domain. While
some existing digital islands can be optioned with digital
ins and outs and reused in the digital system, careful evaluation
of the suitability of any legacy equipment is always prudent.
ADVANTAGE OF DIGITAL
So what is the advantage of digital equipment besides picture
quality? Many digital
products are switchable between 4X3 and 16X9 aspect ratios.
Some units do it with a simple switch, some have software
settings, and some equipment has replaceable parts.
The resolution of the digital system is so great that
sizing or cropping portions of the video frame will have no
perceived effect.
-
Wide Screen Ready
For the longer term, wide screen compatibility is paramount
when selecting digital equipment for front-end control rooms.
Digital equipment, while not necessarily 16X9 in format
should be capable of passing the wide screen aspect ratio.
-
Interchange & Compatibility
The broadcast and production worlds are moving inevitably to
digital, and the expectation of the video community is that
program content is acquired and manipulated in the digital domain.
Interchange of production elements either live or stored
will become exclusively a digital one.
STANDARDS SET
The regulatory and industry standards for digital and high
definition (wide screen) have been set.
The timetable for broadcast conversion has been fixed.
We either follow or we lead.
DO LSVD FACILITIES NEED HIGH
DEFINITION?
Considering the current state of the large screen display
technology, high definition digital equipment gives resolutions that are 25 to 100 times that of the displays.
Standard definition digital television yields resolutions 3
to 14 times the capability of current display products.
For now it seems that the additional cost associated with
going high definition dont make sense.
If your budget
allows it and if youre planning a new facility? DO IT ALL
NOW Go standard definition digital and go wide screen.
Digital equipment has come down in price and in some
instances is more cost effective and higher in quality than
equivalent analog equipment.
Upgrading from
standard to wide screen television is inevitable for the broadcast
industry and in turn, Large Screen Video Display facilities.
LSVD professionals need to be proactive in their efforts to
upgrade their facilities so that they remain current and
marketable.
We have discussed
the historical, regulatory, program, and equipment facets of wide
screen operation. Several
production / artistic solutions have been presented to manage wide
screen aspect ratios irrespective of the technology available.
Equipment
options, ranging from adding the minimum amount of analog
equipment to an existing plant, to building from scratch a
complete digital, wide screen, production facility have also been
discussed.
These solutions
provide immediate answers and prudent migration for the long term.
The fundamental issues in upgrading from standard
television to wide screen technology are ones of production not
hardware. Wide screen presentation can be done with existing analog
equipment. Of course,
better overall production results will be possible with digital,
wide screen capable, equipment as the core of the front-end
production room.
Presentation of
archive 4X3 material on 16X9 screens presents us the opportunity
to use the polyscreen technique to provide more compelling
simultaneous images, and revenue enhancements.
Upgrading
to wide screen provides the viewer / fan with an experience
unmatched at home and meets the fans expectation as home
viewing moves to digital and high definition.
When
the time comes to actually implement wide screen technology,
its best to carefully study the individual equipment needs of
each organization. A detailed migration plan should include a thorough needs
assessment and key design documents including: Comprehensive
Signal Census, Individually
tailored Equipment Lists, Equipment
power & air conditioning Loads, Equipment location & Space
Planning, Rack & Console Elevation Drawings, and equipment
Interconnect Drawings.
It is hoped that
the information presented here will help clarify wide screen
technology for the LSVD professional.
Verdier Ventures,
Inc. (VVINC.)
is a full service video systems design / project management house.
VVINC.
is familiar with all phases of sports / billboard large screen
replay video systems design and construction.
VVINC.
can provide consulting services from feasibility
studies, through proposal / RFP generation and engineering design,
to final completion walkthrough.
Please feel free
to call the author, Jacques Verdier at Verdier Ventures, Inc. if
you have additional questions or if you desire assistance in your
transition to wide screen operation.

| Historical
Perspectives
Aspect ratio concerns have
permeated the entire history of the moving image business
as the following historical perspective shows.
MOTION PICTURES
While the motion picture industry had no aspect ratio
standard for its first 40 years, a 35mm frame with
approximately a 4X3 width to height ratio has been the
preference from the Edison Kinetoscope (1889) to "the
talkies" (1930's). In 1932 the Society of
Motion Pictures Engineers (SMPE) set the Academy aperture
standard of (11x 8 or 1.375:1), very close to a 4X3 ratio.
TELEVISION
As early as 1940 the National Television Systems Committee
(NTSC) studied the issue of aspect ratio for television
and settled upon our familiar 4X3 standard. The NTSC
cited compatibility with the motion picture practice and
the ability to scan movies "without waste" as
driving forces in selecting their standard.
CINERAMA,
CINEMASCOPE, TODD-AO, ET AL
The advent of television and its market penetration made
itself felt by the early 1950s.
By 1953, motion picture attendance had fallen, from
the 1929 high of 95 million, to 46 million despite a
growing US population.
The movie industry decided to fight the audience
loss by offering experiences that could not be gotten
through viewing television at home.
While
not new concepts, 3-D and wide screen pictures exploded on
the motion picture scene.
Even though motion picture attendance continued to
fall to its low of 16 million in 1971, wide aspect ratio
productions thrived, some with screen ratios as wide as
2.75:1 (24X9).
Out
of the plethora of wide screen formats, and as recently as
1993, the film industry was again discussing aspect ratio
standards.
While no standards have been set, the compromise
ratio of 1.85:1 (16.6 X9) is the projection aspect ration
most commonly recommended for 35mm widescreen (nonanamorphic)
movies.
HIGH
DEFINITION, WIDE SCREEN TELEVISION
The development of High Definition (digital) television
has brought us the 1995 SMPTE 267M standard aspect ratio
of 16 X 9 (1.77:1), which is within 5% of the motion
picture wide screen practice of 1.85:1.
Again compatibility with theatrical wide screen
presentations was a factor in developing the TV standard. |
 |
ASPECT
RATIO
The relationship of an images width to its height. |
 |
WIDE
SCREEN
Any aspect ratio wider than 4 X 3 (1.333:1), width to
height. Typically 16X9. |
 |
STANDARD
SCREEN TELEVISION
A television presentation whose aspect ratio matches
the current 4 X 3 standard. |
 |
WIDE
SCREEN TELEVISION
A television presentation whose aspect ratio is 16 X 9
irrespective of the method of acquisition, recording, and
transmission method.
(The technology can be analog or digital.) |
 |
PICTURE
RESOLUTION
The amount of image detail allowed for in any visual
presentation. Each visual technology defines, or limits,
the maximum amount of picture information possible.
Television resolution is measured by the number of
horizontal scanning lines, and spacing of the picture
elements (pixels) within each horizontal line, that
constitutes a complete television frame.
As the number of scanning lines & picture
elements increases, the detail, clarity & crispness of
the picture improves. |
 |
INTERLACE
SCAN
Method of moving the electron beam in a camera or TV
receiver that sends every other line to create a
television field. The
odd lines are sent as the first field, then the even lines
are sent to create the second field.
Odd and even fields are combined together in the
human visual system to make up the complete television
frame. Interlace
scanning requires less information to be transmitted. |
 |
PROGRESSIVE
SCAN
Method of moving the electron beam in a camera or TV
receiver that sends every scanning line in sequence to
create the complete television frame. Progressive scanning
has twice the information of interlace method, but has
fewer motion artifacts and is better for capturing fast
action situations like sporting events. |
 |
NTSC
(ANALOG) TELEVISION
The representation of television image and sound as an
electrical signal that directly corresponds to, is
analogous to, the original visual image and aural
stimulus. The black & white, color and synchronizing
signal elements of the captured image are combined into a
single information stream according to standards set in
the 1940s and early 1950s by the National Television
Systems Committee (NTSC).
Specs: Resolution of 525 scanning lines (483 active) with about 60
interlaced frames per second |
 |
DTV
- DIGITAL TELEVISION
The representation of television image and sound as a
series of numerical values capable of being generated
& manipulated by computer and computer like devices. |
 |
SDTV
- STANDARD DEFINITION (Digital) TELEVISION
A digital television system that provides picture
resolution (number of active scanning lines) that is
equivalent to current NTSC (analog) television standard.
The aspect ratio is intended to be16X9 but can also be
4X3. Single
channel or multiple channel operation is allowed.
Specs: Resolution of 480 active scanning lines with 720
picture elements per line, either interlaced or
progressive, are included in the standard. |
 |
HDTV
- HIGH DEFINITION (Digital) TELEVISION
A television system that provides picture detail,
color purity, and aspect ratio greater than the standard
NTSC television system.
HDTV is always presented in a single channel
widescreen 16X9 aspect ratio.
Specs: Resolution of 1080 interlaced active scanning lines
with 1920 picture elements per line is defined by the
standard. |
# # #
Copyright
Verdier Ventures, Inc. 1998
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