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IT Essentials I v. 3
Module 8
Multimedia Capabilities
© 2004, Cisco Systems, Inc. All rights reserved.
2
Module 8
Multimedia Capabilities
8.1 – Introduction to Multimedia
8.2 – Upgrading Video with Video
Acceleration Board
8.3 – Adding Audio Capabilities with a
Sound Card
8.4 - Overview of CD-RW and DVD
8.5 – Digitizing Video
Introduction to Multimedia
Basic Hardware Required
for Multimedia Upgrades
• Multimedia is a term typically
used to mean the combination of
text, sound, and motion video.
• Multimedia has been described
as the addition of animated
images as in an animated GIF on
the web.
• Multimedia is distinguished from
traditional motion pictures or
movies both by the scale of the
production (multimedia is usually
smaller and less expensive) and
by the addition of audience
participation or interactive
multimedia.
Basic Hardware Required
for Multimedia Upgrades
• The types of computer hardware and software
necessary to develop multimedia on the PC vary.
• The minimum hardware requirements include a
computer monitor, video accelerator card, and sound
adapter card with attached speakers.
The Video Adapter
• A video adapter is an
integrated circuit card in a
computer that provides digitalto-analog conversion, video
RAM, and a video controller
so that data can be sent to a
computer display.
• Almost all displays and video
adapters adhere to the
standard Video Graphics Array
(VGA).
• VGA is how data is passed
between the computer and the
display.
The Video Adapter
• A display or monitor is a
computer output surface
and projecting mechanism
that shows text and often
graphic images.
• Most computer monitors
use analog signals to
display the image.
• This requirement and the
need to continually refresh
the displayed image means
that the computer also
needs a display or video
adapter.
Characterizing Computer Displays
• The Visual Graphics
Array (VGA) mode is
the lowest common
denominator of
display modes.
Depending on the
resolution setting, it
can provide up to 256
colors.
Characterizing Computer Displays
• Dot pitch is the size of an
individual beam that gets
through to light up a point of
phosphor on the screen.
• Computer video displays
can be characterized
according to the following
criteria:
–
–
–
–
Color capability
Sharpness and viewability
The size of the screen
The projection technology
Sound Cards and Speaker Systems
• The output of the sound card
requires additional
amplification if external
speakers are used.
• Sound cards do have the
capability of directly driving
low-power headphones.
• The system internal speaker
can also produce audio
output, or it can be amplified
through external audio
amplifier systems for
applications such as
"Surround Sound".
Common Media File Formats Used in
Multimedia Applications
•
Two data-compression
standards are
commonly used with
digitized video.
1. Joint Photographic
Experts Group (JPEG)
2. Moving Picture Experts
Group (MPEG)
compression standards
MPEG Hardware Versus Software
• Although JPEG provides enough compression to allow
single-frame digitized images to fit on disk drives, fullmotion pictures need much greater compression to be
useful on current technology.
• The MPEG format was developed with a compression
algorithm that delivers compression ratios up to 200:1,
with high-quality video and audio.
Upgrading Video with a
Video Acceleration Board
PCI and AGP Types Examined
• Newer Pentium systems include an advanced Accelerated
Graphics Port (AGP) interface for video graphics.
• The AGP interface is a variation of the PCI bus design that
has been modified to handle data throughput associated
with 3-dimensional graphics.
• The AGP standard provides for a direct channel between
the AGP graphic controller and the computer system main
memory.
All in One
• One of the popular file formats
for video is the Microsoft Audio
Visual Interface (AVI) format
• Video capture cards are
responsible for converting video
signals from different sources
into digital signals that can be
manipulated by the computer.
• The video card samples the
incoming video signal by feeding
it through an A-to-D (analog-todigital) converter.
All in One
• The video capture card converts the YUV format into
an RGB VGA-compatible signal.
• The YUV color model is used for encoding video. Y is
the luminosity of the black and white signal. U and V
are color difference signals. U is red minus Y (R-Y),
and V is blue minus Y (B-Y).
• YUV is a video encoding format that is different than
RGB. An encoding circuit samples the incoming
analog signal, and then performs an operation on it
that is known as Color Space Conversion.
• Color space conversion is the process of converting
the YUV signal into the RGB format acceptable to the
VGA card screen memory.
Installing and Configuring the
Video Card Driver and Software
• The Windows 9x operating
systems should detect the
video card, start the system
with basic VGA video drivers,
and ask whether to install the
manufacturer video drivers.
• The Windows 2000 operating
system will detect the new
video card, tell the user that it
has found the new card, and
then automatically load its
video drivers.
Understanding RAMDAC
and Video Memory
• The RAMDAC chip reads the video memory content,
converts it to analog, and sends it over a cable to the
video monitor.
• The quality of this chip impacts the quality of the
image, speed of the refresh rate, and maximum
resolution capability.
• Refresh rate refers to the number of times per second
that the video display screen can be redrawn.
Understanding RAMDAC
and Video Memory
• The video chip set relies on video memory to render
the image requested.
• The basic element of every video image is a dot (or
pixel). Many dots comprise what is displayed on the
monitor.
• Every dot has a location reserved in video memory.
The maximum number of dots that can be displayed
relates to the resolution.
• Resolution is commonly expressed as a pair of
numbers. Each pair of numbers represents the
maximum possible number of dots on a horizontal
axis and the maximum possible number dots on a
vertical axis.
Flashing the Video Board
with BIOS Updates
• How the image is to be
displayed is the responsibility
of the video BIOS.
• The video BIOS provides the
set of video functions that can
be used by the software
programs to access the video
hardware.
• The video BIOS allows
software to interface with the
video chipset in much the
same way as the system.
Adding Audio Capabilities
with a Sound Card
Sound Card Operation
• A sound card is a device
(either in the form of an
expansion card or a
chipset) that allows the
computer to handle audio
information.
• Basic responsibility of a
sound card is the input,
processing, and output of
audio information.
Sound Card Operation
• Even though there are many types of sound cards
available for different applications, every sound card
has the following basic components:
–
–
–
–
Processor
Converters
Memory
Ports
• Sound cards produce audio (synthesize) using three
distinct methods. These include Frequency
Modulation (FM), Wavetable, and Musical Instrument
Digital Interface (MIDI).
USB, PCI, and Built-in Sound
• USB is a hot-swappable
interface that can be used to
connect many different types of
peripherals to a PC.
• A PCI sound card is an adapter
card with an audio processor that
connects to a motherboard using
a PCI slot.
• Many motherboard
manufacturers integrate both
video and audio options into their
products. The built-in sound has
an audio processor physically
located on a motherboard in the
form of a single chip or chipset.
Removing or Disabling
Outdated Sound Cards
• Before adding a more
capable sound card, older
sound cards should be
removed.
• Removing or disabling
outdated sound cards frees
up resources such as IRQs
and expansion slots.
• Use the proper uninstall
procedures to remove
hardware, related software,
specific drivers and files that
could slow the system down
and to free up resources.
Physical Installation of
Sound Cards
• Installing a sound card is
similar to installing any other
adapter card.
• Refer to the user guide to
determine what hardware
configuration settings should
be made before inserting the
card into the system.
Physical Installation of
Sound Cards
1. Make sure the PC has no power and that all
external devices are disconnected.
2. Remove the cover from the computer case.
3. Locate an available PCI slot to accommodate the
sound card and remove the corresponding slot
cover making sure to save the screw connecting the
cover to the frame.
4. While wearing the anti-static wrist strap, align the
tabs on the bottom side of the sound card with the
open PCI slot and firmly press the card into the slot
keeping even pressure along the side of the card.
5. Replace the cover slot screw to secure the sound
card to the frame.
Connecting the CD-ROM or
DVD Player to the Sound Card
• A common connection is cabling
the CD-ROM or DVDROM drive
to the sound card to produce
digital audio.
• All CD-ROM drives have an
analog audio out connector for
connecting to a sound card.
• Most DVDROM drives offer a
digital audio out connection.
• DVDs are capable of audio
streams containing multiple
channels.
Sound Card Driver and Software
Installation and Configuration
• A sound card driver is the software that allows the computer
operating system to communicate with the hardware.
• Faulty drivers can cause either distorted audio output, no
audio output, or can adversely affect the performance of a
computer.
• Most sound card manufacturers include a disk or CD with their
product.Once the sound card is installed, the driver can be
installed, changed, or updated by using the Device Manager.
MIDI and External-Audio Source
Connection
• Common external-audio
source connections include:
• MIDI port – Musical
Instrument Digital Interface
(MIDI) used to connect
musical devices.
• Microphones can be
connected to a sound card
using the female 3.5mm mini
jack port on the face of the
sound card.
MIDI and External-Audio Source
Connection
• The microphone in port is to be
used with non-amplified sources.
• The line in port is used to capture
audio from amplified sources with
line out options.
• Manufacturers are adding
external digital audio source
capture components.
• The major advantage of using the
digital in option is that there is no
analog to digital conversion
necessary to capture the audio
information.
Overview of CD-RW and DVD
Drives
• Compact Disk, Read Only Memory
(CD-ROMs) are a very popular type
of removable media.
• CD-ROM drives are categorized by
their case type, bus type, and read
speed.
• The CD-ROM drive needs to be
connected to a 40-pin IDE cable that
is then connected to the IDE
controller.
• An internal CD-ROM drive uses the
standard Molex power connector
that supplies 12 volts to other
devices inside a PC.
Recording CDs with
CD-R and CD-RW
•
•
•
CD recorders allow users to "burn"
their own CDs containing music,
data, video, or any combination
thereof.
Currently there are two major
types of CD recorders:
1. CD-R - stands for Compact
Disc - Recordable
2. CD-RW stands for Compact
Disc – Rewritable
It is recommended to be aware of
copyright or licensing limitations
when copying any type of CD.
Digital Audio Extraction Explained
• Digital Audio Extraction (DAE) is the process of
copying audio from a CD to another medium while
keeping the audio in its original digital state.
• Also known as "ripping", most users use DAE
techniques to pull tracks (songs) from an audio CD to
a computer's hard drive and then to a recordable CD.
DVD Players
• DVDs share the same physical size
of a CD-ROM but can handle a
much greater amount of information.
• DVDs are used for movies and
audio, as well as data.
• Computer DVD drives can also play
movies and music as well as read
data discs.
• Manufacturers can now place their
entire program on a single DVD
instead of multiple lower capacity
CDs.
• A DVD drive can read DVDs and
CDs while a CD-ROM drive can only
read CDs.
Recordable DVD
•
There are four different
methods of DVD recording.
1.
DVD-R (recordable) is similar to
CD-R technology in that it allows
the media to be written one time
only
DVD-RAM – Using the Random
Access Memory (RAM) technology
allows users to write and overwrite
discs 100,000 times
The DVD-RW (re-writable) is a
technology designed to address
compatibility and re-recording
issues
DVD+RW - has the ability to use a
variable bit-rate when encoding
certain types of media
2.
3.
4.
CD Recording Formats
• A logical standard
defines the way
information is stored on
the media.
• Physical standards
define where the
information is placed on
a CD.
• Most formats fall within
the "Color Books.
DVD Layering and Formats
• DVD layering is the process
in which the read laser of a
drive is able to focus at
different "layers" inside the
disc.
• DVD physical formats
define the structure of the
disc and the areas to which
data is recorded.
• Currently, there are three
types of DVDs and four
physical formats.
Digitizing Video
Digital Cameras and Video Cameras
Digital camera and docking station
for transferring pictures to the
computer.
• A digital camera has a series of
lenses that focus light to create
an image of a scene just like a
conventional film camera.
• It focuses light onto a
semiconductor device that
records the light electronically
instead of focusing this light
onto a piece of film.
• Many digital cameras use an
LCD screen and fixed storage
connected to the computer to
download the images.
Digital Cameras and Video Cameras
Digital video camera
• There are two types of video
cameras: analog and digital.
• Analog camcorders record video
and audio signals as an analog
track on video tape.
• Digital recorders record
information digitally, as bytes.
This allows the image to be
reproduced without losing any
image or audio quality.
• Digital video can be downloaded
to a computer, where it can be
edited or posted on the Internet.
Hardware and Software Video Capture
• Depending on the compression
methods used, the video clip can
be played back from the Windows
AVI structure or through the
capture card.
• Sources for video capture
normally include VCRs and
camcorders.
• The output from these videoproducing devices tends to be
composite TV or analog S-video
signals.
• A video decoder circuit is used to
convert the analog signal into a
stream of digital signals.
Hardware and Software Video Capture
• The digitized output from the A-to-D converter is
applied to a video compression (ASIC. T)
• The compression chip reduces the size of the file by
removing redundant information from consecutive
frames.
• When the digitized video is recalled for output
purposes, the file is reapplied to the compression
chip, which restores the redundant information to the
frames.
• The analog signals are converted back into the
proper VGA format and are applied to the video-out
connector at the back plate of the card.
Installing and Configuring
a Video Capture Board
• Install the video capture card in one of the unit adapter
slots. This requires that the outer cover of the system
unit be removed.
• Inside the unit, remove the expansion slot cover of a
compatible expansion slot. Make sure the slot can
handle the physical dimension of the card.
• Connect the capture card to the VGA card as directed
by the manufacturer installation guide.
• Install any antennas that must be connected to the card
for the intended application.
• Most capture card software provides a preview window
that enables the user to view the video coming from the
video source.