Digital/HD Cable TV
exactly is Digital and High-Definition Television?
(such as the EPB’s Power Digital Package) delivers a picture that is
clear and sharp, without the many reception problems associated with
regular analog TV. Going beyond Digital, High-Definition TV (HDTV)
offers you the very best in both visual and audio quality. The enhanced
viewing experience of HDTV is unquestionably superior to anything
digital TV differ from traditional analog TV, with which we all grew up?
analog transmits only the video signal with no other information. A
major problem with analog signals is that between the transmitter and
your TV set, many things can interfere, distorting the picture you see.
From a plane flying overhead, to hilly terrain, tall buildings and even
atmospheric conditions, all are obstacles that can interrupt the
weaker analog signal can cause "snowy" pictures - something with which
those of us who remember the days before EPB cable TV are too familiar.
Digital TV signals are made up of coded instructions - the same "ones
and zeros" that make your computer work, and give life to your CD's and
DVD's. Your receiver isn't concerned with the signal strength, or what
conditions exist between you and the transmitter. As long as the signal
gets to the receiver, it can read the code and reproduce a near-perfect
picture. With digital broadcasting, bad reception is a thing of the
past. One reason cable TV caught on is because it delivers clear TV
pictures without regard to the viewer's location. Digital eliminates
"snow" and "ghosting" caused by the weak signals from distant or
blocked transmitting towers.
digital and analog TV signals get weaker the farther they travel away
from the transmitting tower. On an analog TV, the picture slowly
deteriorates from bad to worse for more distant receivers. However, the
picture on a digital set will stay perfect until the signal becomes too
weak for the receiver to distinguish between a 1 and a 0, at which
point the image disappears completely. The bottom line ... you either
receive a 100% perfect quality picture, or nothing at all.
now we’ve talked about the EPB’s Power Digital Package (digital cable).
What is HDTV - High-Definition TV? And what’s the difference between
Digital and High-Definition?
High-Definition TV, the picture displayed on your TV is digitally
transmitted, but it must also meet certain standards in order for it to
be "true HDTV." A High-Definition TV displays pictures that contain
significantly more detail, resulting in much sharper pictures.
viewed on TV screens are made up of small picture elements known as
"pixels." Each of these pixels is made up of three, closely spaced dots
of color - red, blue and green. Combined together on the TV's screen
and viewed from a distance, the colors are seen as one. On traditional
TV's, 256 levels of intensity are possible for each of the three
colors. The result is a range of 16.8 million colors. The pixels in the
analog system are slightly taller than their width. Get up close to an
analog screen - especially the larger projection sets - and you can
easily see the red, blue and green rectangles. This is why distortion
is sometimes seen on traditional TV's.
in HDTV sets are square; they are also smaller, and spaced closer
together. There can be (4 ½) HDTV pixels in the same space that a
single NTSC pixel requires. The result is that
High-Definition-Television can display at least 4 ½ times more detail
than a regular analog TV.
"aspect ratio" and why is "wide screen" TV the digital standard?
refers to the ratio between the horizontal measurement and the vertical
measurement of the screen. The two aspect ratios used in digital TV’s
are (4:3) and (16:9). That is, (4) units wide by (3) units high or (16)
units wide by (9) units high. Your analog TV has an aspect ratio of
(4:3); the screen appears almost "square" because it has just slightly
more width than height.
TV's (16:9) wide-screen is approximately 1/3 larger than a comparable
(4:3) set. The 16:9 wide-screen aspect ratio is the standard for
Digital HDTV (because much more information can be displayed on the
screen). Actually, the 4:3 aspect ratio was originally developed in
1889 at the famed Thomas Edison Laboratory. Film for early motion
picture cameras was 1" wide and 3/4" high. In the 1950's, Hollywood
found they needed to provide the public with a reason to buy movie
tickets (it was easier for them to sit home and enjoy TV). Besides
trying innovations like 3-D, studios experimented with the aspect
ratio. "Cinemascope" was one of the early wide-screen ratios that can
still be seen today. The reasoning that led to wide-screen formats is
simply that the wider view is closer to the human field of vision.
Because the viewer is visually drawn more into the action with
wide-screen, the enjoyment level is enhanced. In the theater,
wide-screen formats were easy to reproduce. They simply use more or
less of the screen, as needed. However, as movies were displayed on TV
screens, and later made into videos, the aspect ratio became more
complicated. Initially, movies were "cropped" to fit 4:3 analog-TV
sets. This is accomplished by a process called "pan and scan," which
involves moving the 4:3 viewing area back and forth, to center the
scene on the primary action. While pan and scan is okay if nothing is
occurring in the peripheral areas, often, important information in
these areas is cut off. To enable movies to be viewed in their
original, wide screen aspect, the "letter box" process was developed.
With "letter boxing," the picture's height is reduced, allowing the
full width of the image to fit the TV screen. This enables you to see
the entire scene the way it was filmed.
reducing the image height requires removing some information that
leaves a portion of the vertical area blank. The image is displayed in
the center of the screen, with the blank area divided into two,
horizontal, black "bars" across the top and bottom of the screen. These
bars increase or decrease, as the aspect ratio changes. However,
letter-boxed movies, originally filmed in extra-wide format, can be
especially troublesome to watch when viewed on smaller TV screens, due
to the extremely-reduced viewing area.
seen the EPB's high-definition yet? Stop by our office, 8:00am-4:30pm
weekdays and see it for yourself.