98年度高畫質電視的未來與發展
國家通訊傳播委員會 專業技術講習課程
高畫質電視面面觀
– HDTV Overview –
石佳相博士
Taiwan DTV Committee
社團法人台灣數位電視協會
台灣數位電視協會 常務理事
華電聯網 新媒體應用整合處 副總經理
2009.04.17
Taiwan DTV Committee
社團法人台灣數位電視協會
Dr. C. Stone Shih is Vice President of New Media Division, HwaCom Systems Inc. His work
experience and expertise concentrates on digital broadcasting technology, multimedia
platform technology, as well as digital set-top-box design and system integration. To help
promoting digital TV developments in Taiwan, Dr. Shih also serves as important leaders in
various industrial organizations and provides consultancy services to government offices.
Prior to HwaCom, Dr. Shih was CEO and co-founder of DAWN TV Technology Corporation as well as Vice President of
Communication Department, CMC Magnetics Corporation. Before Joining CMC, Dr. Shih co-initiated a DVB-S based DTH
service platform Pacific Digital Media (PDM) in Taiwan (PDM became TV-Plus later). Dr. Shih was CTO of the PDM
operations which he was responsible for the technical aspects of the PDM DTH platform developments. The PDM DTH
business plan was drafted while Dr. Shih was Vice President of TV Time Entertainment Networks (TVTime), a cable
channel provider in Taiwan. Prior to TVTime, Dr. Shih was with a digital set-top-box vendor Visionetics in Science-Based
Industrial Park, Hsinchu, Taiwan. While with Visionetics, Dr. Shih led a team finishing a DVB Set-Top-Box development
project which was partially funded by the Industrial Development Bureau, Ministry of Economic Affairs, R.O.C.
(IDB/MoEA).
Earlier in the US, Dr. Shih worked on a video server project in a VOD trial while he was with IBM T.J. Watson Research
Lab. at Yorktown Heights, NY. After IBM, Dr. Shih co-initiated a satellite based cable content provision company
Entertainment Research and Applications (ERA) in Los Angeles.
Dr. Shih received his Ph.D. and M.S. in Computer System Engineering from University of Massachusetts and his B.S. in
Electrical Engineering from National Taiwan University.
Dr. Shih is participating and is a member of:




IEEE Computer Society, Communications Society, and
Broadcast Technology Society
Digital Video Broadcasting (DVB, a DTV Launching Project of
EBU / ITU)
Broadcast Mobile Convergence Forum (bmcoforum, an
international organization for Mobile Broadcast Services)
Audio and Video Coding Standard Workgroup of China (AVS
Workgroup of China)
2009/04/17

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
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Digital Video Industry Development Program Office,
IDB/MoEA (Senior Consultant)
Taiwan DTV Industry Alliance (Co-Chair, Representative of
Industry, of the DTV Standards Working Group)
Taiwan DTV Committee (Director General, Board Member)
Taiwan Digital Video Association (Board Member)
Taiwan Mobile TV Industry Forum (Vice Chairman)
HDTV Overview
-1-
Taiwan DTV Committee
社團法人台灣數位電視協會
Focuses



電視發展史與高畫質電視的演進
高畫質電視的相關技術與標準
高畫質電視的產品與應用
2009/04/17
HDTV Overview
-2-
Taiwan DTV Committee
社團法人台灣數位電視協會
Outlines







History of TV
The search for TV Standards
Technical Aspects
Products and Implementations
FCC Standard Setting in HDTV
The HDTV spectrum allocation at the FCC
Concluding Remarks
2009/04/17
HDTV Overview
-3-
Taiwan DTV Committee
社團法人台灣數位電視協會
Outlines







History of TV
The search for TV Standards
Technical Aspects
Products and Implementations
FCC Standard Setting in HDTV
The HDTV spectrum allocation at the FCC
Concluding Remarks
2009/04/17
HDTV Overview
-4-
Taiwan DTV Committee
社團法人台灣數位電視協會
History of TV

1842 Alexander Bain managed to transmit a still
image over wire. First fax machine!

In 1884 Paul Gottlieb Nipkow went a step further,
and discovered (and patented) a way to scan a
moving image and transmit it sequentially. Birth
of mechanical television!
2009/04/17
HDTV Overview
-5-
Taiwan DTV Committee
社團法人台灣數位電視協會
2009/04/17
Mechanical Television
HDTV Overview
-6-
Taiwan DTV Committee
社團法人台灣數位電視協會
Mechanical Television
John Logie Baird, a
Scottish inventor,
demonstrated what many
refer to as the first
television broadcast on
January 26, 1926. Baird’s
grayscale image,
presented to members of
the Royal Institution in
London had only about 30
lines of resolution.
2009/04/17
HDTV Overview
-7-
Taiwan DTV Committee
社團法人台灣數位電視協會
2009/04/17
First “mass produced” TV set
HDTV Overview
-8-
Taiwan DTV Committee
社團法人台灣數位電視協會
Mechanical Television



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
1927 - First TV broadcast in the US
Herbert Hoover
From NY to Washington
Had about 50 scanning lines
Broadcast by wire and radio
2009/04/17
HDTV Overview
-9-
Taiwan DTV Committee
社團法人台灣數位電視協會
Electronic Television



1934 Philo
Farnsworth
demonstrated an allelectronic system
Less cumbersome
than mechanical TV
Quickly gained
popularity
2009/04/17
HDTV Overview
- 10 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Outlines







History of TV
The search for TV Standards
Technical Aspects
Products and Implementations
FCC Standard Setting in HDTV
The HDTV spectrum allocation at the FCC
Concluding Remarks
2009/04/17
HDTV Overview
- 11 -
Taiwan DTV Committee
社團法人台灣數位電視協會
The search for standards: the FCC & the NTSC


FCC Established by the Communications Act of
1934.
Radio Manufacturers Association (RMA)
recommended a standard for television using
441 horizontal scan lines and 30 frames per
second with a 4:3 aspect ratio.
2009/04/17
HDTV Overview
- 12 -
Taiwan DTV Committee
社團法人台灣數位電視協會
The search for standards: the FCC & the NTSC


FCC urged the RMA to form the National
Television System Committee (NTSC) in 1940.
1941 - NTSC established its first set of
standards, which kept the 4:3 aspect ratio but
called for a higher resolution image with 525
scan lines refreshing at a rate of 30 interlaced
frames, or 60 fields per second. (263 lines
followed by 262).
2009/04/17
HDTV Overview
- 13 -
Taiwan DTV Committee
社團法人台灣數位電視協會
The search for standards: the FCC & the NTSC


FCC allotted 6 MHz slices of bandwidth to TV
stations.
Eventually covered a frequency range spanning
from 54 MHz to 890 MHz on the broadcast
spectrum.
2009/04/17
HDTV Overview
- 14 -
Taiwan DTV Committee
社團法人台灣數位電視協會
The search for standards: the FCC & the NTSC

1950s brought the addition of color (Home
viewing was brought a step closer to cinema).


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

CBS Color System failed due to compatibility issues
1953 - The NTSC standard had to be revised to
adapt to color TV.
Engineers split the signal into two components:
luma, which contained the brightness
information, and chrominance, which contained
the color information.
Field refresh rate of 60 Hz was slowed down by a
factor of 1000/1001 to 59.94 Hz.
Broadcast television downshifted from 30 to
29.97 frames per second.
2009/04/17
HDTV Overview
- 15 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Same old standard

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Many improvements were made in cameras, production
and broadcast gear, and in television receivers.
Despite advances, the quality of analog broadcast was still
limited to the NTSC standard of 60 fields and 525
horizontal scan lines.
Stuck with more or less same standards created in 1941.
By the 1980s, manufacturers had been developing and
using both analog and digital HD systems.
It became clear that the replacement for analog would use
digital television technology.
Needed a new set of standards to ensure compatibility.
2009/04/17
HDTV Overview
- 16 -
Taiwan DTV Committee
社團法人台灣數位電視協會
ATSC




Formed in 1982
The Advanced Television Systems Committee is
a not-for-profit organization whose purpose is to
develop standards for the transition to DTV.
Its published broadcast standards are voluntary
unless adopted and mandated by the FCC.
ATSC proposed DTV Standard (A/53) that
specifies the protocol for high-definition
broadcasting through a standard 6MHz channel.
2009/04/17
HDTV Overview
- 17 -
Taiwan DTV Committee
社團法人台灣數位電視協會
DTV Switchover



In December 1996, the FCC adopted standards
proposed by the ATSC, mandating that
broadcasters begin broadcasting digitally.
WRAL of Raleigh, North Carolina was the first
station to broadcast in digital.
FCC’s current plan is to terminate analog
broadcasting by June 2009.
2009/04/17
HDTV Overview
- 18 -
Taiwan DTV Committee
社團法人台灣數位電視協會
DTV, SDTV, & HDTV




NTSC standards defined one analog format
ATSC created a framework supporting multiple
digital formats
There is considerable confusion among
consumers regarding SDTV, DTV and HDTV.
Broadcaster do not have to broadcast in HD, just
in DTV.
2009/04/17
HDTV Overview
- 19 -
Taiwan DTV Committee
社團法人台灣數位電視協會
DTV Formats
HDTV/ Horizontal
SDTV
lines
Vertical
lines
Aspect
Ratio
Frame Rate
SDTV
640
480
4:3
60p, 60i,
30p, 24p
SDTV
704
480
4:3 and
16:9
60p, 60i,
30p, 24p
HDTV
1280
720
16:9
60p, 30p, 24p
HDTV
1920
1080
16:9
60i, 30p, 24p
Note: Non-integer formats (eg. 29.97) omitted for clarity.
2009/04/17
HDTV Overview
- 20 -
Taiwan DTV Committee
社團法人台灣數位電視協會
HDTV & SDTV Comparison
Increasing picture resolution
and sound quality
SD
Image
Definition
Audio
2009/04/17
HD
704/720
pixels per line
480/576
Active lines
( from 200 000
to 400 000 pixels)
1280 or 1920
pixels per line
720 or 1080
active lines
( from 900 000
to 2 000 000 pixels)
Mono or Stereo
Sound 5.1
Digital Dolby
6 tracks
HDTV Overview
- 21 -
Taiwan DTV Committee
社團法人台灣數位電視協會
HD Video Formats
720
0
1280 1440
1920
345,600
480
576
414,720
921,600
720
1,552,200
2,073,600
1080
1152
2009/04/17
1,658,880
HDTV Overview
- 22 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Standard Definition Television SDTV



The current television display system
4:3 aspect ratio picture, interlace scan
Australia/Europe




625 lines - 720 pixels x 576 lines displayed
50 fields/sec 25 picture frames/sec
414720 pixels total
USA/Japan



2009/04/17
525 lines - 704 pixels x 480 lines displayed
60 fields/sec 30 picture frames/sec
337920 pixels total
HDTV Overview
- 23 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Enhanced Definition TV Sets (EDTV)

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Enhancements on TV sets
Intermediate step to HDTV
Doubled scan rate - reduce flicker
Double lines on picture - calculated
Image processing - ghost cancelling
Wider aspect ratio - 16:9
Multi-channel sound
2009/04/17
HDTV Overview
- 24 -
Taiwan DTV Committee
社團法人台灣數位電視協會
High Definition Television - HDTV

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Not exactly defined - number of systems
System with a higher picture resolution
Greater than 1000 lines resolution
Picture with less artefacts or distortions
Bigger picture to give a viewing experience
Wider aspect ratio to use peripheral vision
Progressive instead of interlaced pictures
2009/04/17
HDTV Overview
- 25 -
Taiwan DTV Committee
社團法人台灣數位電視協會






HDTV – Have We Heard This Before?
The very first TV system had just 32 lines
When the 405 line system was introduced
it was called HDTV!
When 525/625 line black & white came along
it was called HDTV!
When the NTSC/PAL colour system was introduced
it was called HDTV by some people.
Many of the enhanced TV (EDTV) sets introduced
they were labelled as HDTV.
Now we have 1000+ line systems and digital
television - guess what?
Its called HDTV!
2009/04/17
HDTV Overview
- 26 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Outlines







History of TV
The search for TV Standards
Technical Aspects
Products and Implementations
FCC Standard Setting in HDTV
The HDTV spectrum allocation at the FCC
Concluding Remarks
2009/04/17
HDTV Overview
- 27 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Standards and formats
A jungle of standards and formats
SMPTE 295 M
1998
MUSE
SMPTE 296 M
Vision 1250
SMPTE 274 M
1998
2009/04/17
HDTV Overview
- 28 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Technical Aspects
Formats are described by:
Number
Number
of active pixels of active lines
per line
per frame
Scanning
mode
Picture
aspect ratio
Frame rate
Current main standards are:
SMPTE 274 M
2009/04/17
SMPTE 296 M
HDTV Overview
ITU-R BT.709-5
- 29 -
Taiwan DTV Committee
社團法人台灣數位電視協會
SMPTE 274 M
11 formats at 1920 X 1080,
8 progressive , 3 interleaved
2009/04/17
HDTV Overview
- 30 -
Taiwan DTV Committee
社團法人台灣數位電視協會
SMPTE 296 M
8 formats at 1280 x 720, all progressive
And a war of standards…
2009/04/17
HDTV Overview
- 31 -
Taiwan DTV Committee
社團法人台灣數位電視協會
And then ITU-R BT.709-5…
This standard unifies the different American, European and Japanese HD systems,
and establishes a bridge with digital cinema. It recommends:
–A unique Common Image Format 1920 x 1080.
–A common data bit rate 1,485 Gigabits/.s
– Allowing all the picture rates of interleaved and progressive television and
cinema picture rates:
– ( 50i,60i,25p,25 psf,30p,30 psf,50p and 60 p) and(24 p and 24 psf)
2009/04/17
HDTV Overview
- 32 -
Taiwan DTV Committee
社團法人台灣數位電視協會
The Codecs



Codec is short for compressor-decompressor or
coder-decoder, and refers to a manner in which
data is compressed and uncompressed.
Broadcast and production codecs differ.
In order to squeeze the data into a form that can
be reliably broadcast within a 6 MHz section of
bandwidth, the HDTV signal must be
compressed at about a 50:1 ratio.
2009/04/17
HDTV Overview
- 33 -
Taiwan DTV Committee
社團法人台灣數位電視協會
The Compression Codecs



Most DTV broadcasts (terrestrial, cable &
satellite) use MPEG-2.
MPEG-2’s compresses the video into groups of
pictures (GOPs) not individual frames. Images
are divided into macroblocks, which are areas of
16 x 16 pixels.
GOPs are created with three types of pictures: I,
P, and B frames. I frames are intracoded frames.
P are predicted frames and B are bidirectional
frames.
2009/04/17
HDTV Overview
- 34 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Data services

In addition to audio & video, DTV contains
metadata - auxiliary information related to the
program or its content including audio dialog
level info, closed captioning, format descriptor
tags, and digital rights management (DRM) data.
2009/04/17
HDTV Overview
- 35 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Scanning modes


HDTV allows for both interlaced and progressive content.
Progressive mode is preferred by the HDTV.
Interlaced display
2009/04/17
HDTV Overview
- 36 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Scanning mode comparison
Flicker and
feathering
Interlaced, Progressive,
Progressive Segmented Frames
-source Image
progressive
scanning
(1 pass)
interlaced
scanning
(2 passes)
No flicker,
no feathering
1st field
2nd field
Segment B
Segment A
Segmented frames
2009/04/17
HDTV Overview
No flicker or
feathering and
easier compatibility
with interlaced mode
37
Taiwan DTV Committee
社團法人台灣數位電視協會
Flickering effects of Interlaced mode


Flicker is visible fading between cycles displayed on video
displays, especially the refresh interval on cathode ray tube
(CRT) based screens.
Flicker occurs on CRTs when they are driven at a low refresh
rate, allowing the screen's phosphors to lose their excitation
(afterglow) between sweeps of the electron gun.



For example, if a CRT computer monitor's vertical refresh rate is set to 60 Hz,
most monitors will produce a visible "flickering" effect, unless they use
phosphor with long afterglow. Most people find that refresh rates of 70-90 Hz
and above enable flicker-free viewing on CRTs. Use of refresh rates above 120
Hz is uncommon, as they provide little noticeable flicker reduction and limit
available resolution.
A similar effect occurs in PDPs during their refresh cycles.
Since the shutters used in LCD for each pixel stay at a steady
opacity, they do not flicker, even when the image is refreshed.
The backlights of such displays do flicker, but typically operate
in the range of 150-250 Hz.
2009/04/17
HDTV Overview
- 38 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Feathering effects of Interlaced mode
Interlaced
Progressive
2009/04/17
HDTV Overview
- 39 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Frame rates



DTV supports multiple frame rates including 24p,
25p, 30p, 50p, 60p, etc.
24p is the standard film frame rate used by the
motion picture industry for years.
Allows for easier transfer to / from film.
2009/04/17
HDTV Overview
- 40 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Aspect ratios


16 x 9 aspect ratio more closely matches
widescreen film formats.
DTV supports the display of traditional, standard
resolution, 4:3 content.
2009/04/17
HDTV Overview
- 41 -
Taiwan DTV Committee
社團法人台灣數位電視協會
2009/04/17
Aspect ratios
HDTV Overview
- 42 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Conversion





Up-converting (converting to a superior format)
Down-converting (converting to a lesser format)
Scaling / sizing
Aspect ratio manipulation / conversion
Common to see broadcasters delivering images
with the improper aspect ratio.
2009/04/17
HDTV Overview
- 43 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Up Conversion -- SD to HD conversion

The main functions that an up converter must
achieve, are:
 Calculation of missing pixels and lines




Frame rate conversion
Resizing
De-interlacing
Quality of the output depends mainly on the
de-interlacing process which is the most difficult
to achieve.
2009/04/17
HDTV Overview
- 44 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Aspect ratio manipulation and resizing (SD -> HD)
4:3
16:9
Zoom + Top/ Bottom Crop
4:3
16:9
Side Panel
2009/04/17
HDTV Overview
- 45 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Aspect ratio manipulation and resizing (SD -> HD)
4:3
16:9
Stretching
16/9
4/3
left + right Stretching
2009/04/17
HDTV Overview
- 46 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Up Conversion -- Quality issues

It is clear that up conversion :


Emphasises noise
Introduces impairments:




in the transients,
in fast moving pictures
and in low light pictures ( Stairs effects, blocks, and
shifts).
Improved processes must be required to
reduce these artefacts as much as possible
2009/04/17
HDTV Overview
- 47 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Frame rate conversion - 3-2 pulldown
Used to convert film or 24p to interlaced 29.97
2009/04/17
HDTV Overview
- 48 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Outlines







History of TV
The search for TV Standards
Technical Aspects
Products and Implementations
FCC Standard Setting in HDTV
The HDTV spectrum allocation at the FCC
Concluding Remarks
2009/04/17
HDTV Overview
- 49 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Products and Implementations



HDTV production typically begins with a highdefinition camera, or a project shot on film then
converted to a digital format.
Other means are possible. Much of Tim Burton’s
recent stop-motion feature, The Corpse Bride
was shot with a Canon digital still camera, and
then transferred to digital video for editing.
Many commercials, cartoons, and full-length
features have been created solely with animation
software.
2009/04/17
HDTV Overview
- 50 -
Taiwan DTV Committee
社團法人台灣數位電視協會
HDTV Cameras



HDTV cameras have been used for private
applications long before the ATSC standards
were in place.
Higher-end production cameras suitable for
studio or digital cinematography can cost well
over $100,000. (That’s not including the lens!)
Sub-$1,000 range targeted to consumers are
pushing sales on the lower end.
2009/04/17
HDTV Overview
- 51 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Recording and Playback

Recording & playback can be done in many
ways:




2009/04/17
Tape
Hard-drive
Optical disc
RAM
HDTV Overview
- 52 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Recording and Playback



D-VHS – This consumer format from JVC
records onto VHS tapes using an MPEG-2
stream at up to a 28.2 Mbps data rate.
HDV – Canon, Sony and JVC offer relatively
lower cost cameras that record at a maximum
resolution of 1440 x 1080. HDV uses a form of
MPEG-2 compression that results in a 25 Mbps
signal that can be recorded onto miniDV
cassettes.
DVCPRO HD – Also known as D12, DVCPRO HD
was developed by Panasonic and has versions
that record on magnetic tape as well as memory
cards.
2009/04/17
HDTV Overview
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Taiwan DTV Committee
社團法人台灣數位電視協會
Recording and Playback




XDCAM HD - Sony’s tapeless format records
onto Blu-Ray optical discs using several
possible codecs. It can record HD content using
MPEG-2 encoding at up to 35 Mbps or DV25 for
DVCAM, and MPEG-4.
D-5 HD – Developed by Panasonic in 1991, the D5 format has been updated to HD. Handles 720
and 1080 content at most possible frame rates.
HDCAM - Sony’s format records onto 1/2”
videocassettes at a number of possible frame
rates. It uses a 593 Mbps data rate and supports
up to 8 channels of audio.
HDCAM SR - data rates up to 8800 Mbps with up
to 12 audio channels.
2009/04/17
HDTV Overview
- 54 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Editing



MPEG-2 works well for transmission, but is not
an ideal choice for editing due to its GOP
structure and high compression ratio.
Editors typically want access to discreet frames
with less compression.
In addition to the standard bit depths of 8 and 10,
there are also higher end, 16-bit codecs available
from companies like Pinnacle and Digital
Anarchy.
2009/04/17
HDTV Overview
- 55 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Editing Storage




HD content, especially uncompressed, takes
massive amounts of bandwidth and disk space.
Consider this comparison:
An hour of DV footage with a stereo pair of 16-bit
audio tracks takes approximately 14 GB of disk
space.
An hour of 10-bit 1920 x 1080 HD footage with a
pair of 24-bit audio channels requires nearly 600
GB of space.
2009/04/17
HDTV Overview
- 56 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Display Technologies

CRT - CRT monitors draw the lines one after the next, from
top to bottom to make an entire frame. Generally speaking
they have pleasing color balance performance and wide
viewing angles. Because of their use of vacuum tubes, the
displays can’t be constructed much larger than 40” or so.

Plasma – Plasma HDTV sets are thin and are made up of
cells that correspond to pixels sandwiched between glass
plates. Plasma cells contain three separate gas-fill subcells, one for each color. When a current is applied to a
sub-cell, it ionizes the gas emitting ultraviolet light. The
ultraviolet light in turn excites fluorescent substances in
the sub-cells that emit red, blue or green light.
2009/04/17
HDTV Overview
- 57 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Display Technologies

LCD – LCD HDTV monitors work by casting light through
an array of cells sandwiched between two polarized
planes. LCD monitors are less expensive than CRTs to
manufacture and come in both flat panel and rear
projection varieties. Flat panel, direct-view monitors have
become popular as computer and DTV monitors as they
are bright, use less electricity than CRTs, and have a
relatively long life span.

DLP – Digital light processing is a technology used in
projection displays. In DLP monitors, light is reflected off
an array of microscopic hinged mirrors. Each tiny mirror
corresponds to a visible pixel. The light is channeled
through a lens onto the surface of the screen. Single chip
DLP projectors can display 16.7 million colors. 3-chip
projectors can display 35 trillion colors.
2009/04/17
HDTV Overview
- 58 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Display Technologies

LCoS – Similar to DLP, LCoS projection systems
use liquid crystals instead of mirrors to block
light. The liquid crystals are arranged in a grid in
front of a highly reflective surface.
2009/04/17
HDTV Overview
- 59 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Outlines







History of TV
The search for TV Standards
Technical Aspects
Products and Implementations
FCC Standard Setting in HDTV
The HDTV spectrum allocation at the FCC
Concluding Remarks
2009/04/17
HDTV Overview
- 60 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Old Technology towards New Technology

When a new technology is invented, there are a
few interesting questions.

The effects of compatibility between two different
generation of technologies on firms and customers?
Old Technology
vs.
New Technology
Old Hardware
New Hardware
Old Software
New Software
Backward compatible
Forward compatible
2009/04/17
HDTV Overview
- 61 -
Taiwan DTV Committee
社團法人台灣數位電視協會
The Compatibility issues

Non-compatible: Nintendo

Backward compatible:





Forward compatible:



CD/DVD,
Sony PS/PS2,
MS DOS/Window O/S,
BW/Color TV
BW/Color TV,
Color/HDTV
For increasing the adoption of color TV, which one is
better?
(1) B/W can receive color TV signal.
(2) B/W cannot receive color TV signal.
2009/04/17
HDTV Overview
- 62 -
Taiwan DTV Committee
社團法人台灣數位電視協會
The Story of FCC Color TV decision

The color TV technology used in the US today is
known as the National Television Systems
Committee (NTSC) system.

In 1941, RCA, the owner of NBC and a leading
manufacturer of black-and-white sets, was a
powerful force in the radio and television world.
Throughout the 1940s, CBS, the leading TV
network, was pushing for the adoption of the
mechanical color TV system it was developing.

2009/04/17
HDTV Overview
- 63 -
Taiwan DTV Committee
社團法人台灣數位電視協會
The Story of FCC Color TV decision

The FCC adopted the CBS system in Oct 1950





In 1953, the FCC officially reversed its 1950 decision so
that B/W TV sets could receive color TV signals.


A major obstacle for the CBS system was that it was not
backward-compatible: B/W sets would not be able to receive
color program.
CBS had no manufacturing capability and no alliances with
manufacturers.
Since a major consumers with B/W TVs could not receive
color TV signals, limited programs in color were available.
To customers, color sets offer little added value because of
the limited programs in color.
Then, the number of programs in color increases.
Forward compatibility increased the color TV adoption.
2009/04/17
HDTV Overview
- 64 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Lessons learnt from FCC Color TV decision



TV system has three major components:
programming, distribution equipment and
reception equipment.
The effects of compatibility, a direct effect and
an indirect effect.
For HDTV to succeed, HDTV programming must
be available, HDTV signals must be delivered to
home, and consumers must purchase HDTV
receivers and videotape machines.
2009/04/17
HDTV Overview
- 65 -
Taiwan DTV Committee
社團法人台灣數位電視協會
HDTV Development in the U.S.

To broadcasters as a group HDTV was a threat, not a promise




Each individually might want to adopt HDTV, but as a group all might be
worse off


A prisoners’ dilemma structure among broadcasters
In broadcasting, they could do that to prevent HDTV’s adoption:



HDTV increase their costs considerably, e.g. transmission equipment costs
$38m
They cannot charge more for an improved service
They only benefit if viewers watched more TV. They probably would but not by
much because on average each TV household already watches seven hours a
day.
They discourage FCC from moving quickly to set standards for HDTV
The claim that the already developed technology was unsuitable and delay any
implementation
Broadcasting has traditionally been organized around local stations

2009/04/17
These terrestrial broadcasters face increasing competition
 Cable TV
 Direct broadcast satellites - signals sent to home satellite dishes
 Fiber optic networks to homes
HDTV Overview
- 66 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Outlines







History of TV
The search for TV Standards
Technical Aspects
Products and Implementations
FCC Standard Setting in HDTV
The HDTV spectrum allocation at the FCC
Concluding Remarks
2009/04/17
HDTV Overview
- 67 -
Taiwan DTV Committee
社團法人台灣數位電視協會
The challenges of the HDTV spectrum allocation

Competition for spectrum at the FCC


FCC considered reallocating some unused parts of
TV’s ultrahigh frequency band (UHF) to cellular service
Scarce Spectrum Allocating Criteria

Scarce Spectrum should be reserved for applications
that


2009/04/17
are highly valued; and
cannot easily be offered without using such spectrum
HDTV Overview
- 68 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Challenges toward Terrestrial HDTV

A heavily squeezed HDTV system






Extra costs
Compromised quality
Reduced scope for later enhancements
Less spectrum available for other uses
Even less spectrum for other uses when
additional spectrum was allocated to existing
terrestrial broadcasters to reduce interference
between adjacent channels
Major social cost of implementing HDTV through
terrestrial broadcast is the use of scarce
spectrum space
2009/04/17
HDTV Overview
- 69 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Challenges toward Terrestrial HDTV


HDTV signals can easily be sent via cable or via
satellite signals that do not use the crowded and
valuable portion of spectrum suitable for
ground-to-ground transmissions.
A new generation of DTV presents an
opportunity to reconfigure use of the spectrum



Provide TV service via satellite or via cable
Can free up critical spectrum space for a number of
alternative technologies for future use
But
FCC decided to fit HDTV into the already
crowded terrestrial TV spectrum
2009/04/17
HDTV Overview
- 70 -
Taiwan DTV Committee
社團法人台灣數位電視協會




Also decided by the FCC…
FCC decided to protect the installed base in the
hands of consumers as well as to protect the
existing broadcast industry
It decided that the introduction of HDTV must not
strand owners of existing sets
Either the HDTV standard must be receiver
compatible or else NTSC broadcasts must be
“simulcast” alongside HDTV broadcasts during
a probably long transition period
FCC has decided to use a simulcast approach
2009/04/17
HDTV Overview
- 71 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Outlines







History of TV
The search for TV Standards
Technical Aspects
Products and Implementations
FCC Standard Setting in HDTV
The HDTV spectrum allocation at the FCC
Concluding Remarks
2009/04/17
HDTV Overview
- 72 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Usage/Saturation

A recent survey carried out by Panasonic in December of
2005 reported that 26% of US households will own or will
purchase a high-definition set by the end of 2006.

The NAB (National Association of Broadcasters) maintains
a growing list of stations that have made the move to
digital broadcast. In December 2005, 1,550 stations were
broadcasting digitally.

European broadcasters are very interested in launching
HDTV services based on a combination of new
technologies → second generation HDTV



2009/04/17
coded at 7.5 Mbit/s using different video compression
schemes
MPEG-4 AVC & Microsoft VC1
software decoding
HDTV Overview
- 73 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Impact of HDTV


Broadcasters & consumers spend more $
Increased visual clarity has forced designers to
spend considerably more money on sets, set
dressings and props

DVD battle being waged

Blu-Ray vs. HD-DVD
2009/04/17
HDTV Overview
- 74 -
Taiwan DTV Committee
社團法人台灣數位電視協會
Final Words

As NTSC/PAL retires, HDTV programming, products, and
production services will continue to grow exponentially.

Move will be cheaper, quicker, and easier as products and
services become more widespread and people grow
accustomed to the new technology.

HDTV has brought a more cinematic experience into
viewer’s homes and with digital cinema, delivered the film
industry a few of the benefits of television.
However, HDTV still has much lower resolution than 70mm
film. It’s a matter of time before some will begin pressuring
for another increase in quality.
2009/04/17
HDTV Overview
- 75 -
Taiwan DTV Committee
社團法人台灣數位電視協會
2009/04/17
HDTV Overview
- 76 -