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Unformatted text preview: All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20 C HAPTER Multimedia 20 In this chapter, you will learn how to
• Describe how to implement sound in a PC
• Install and configure video capture hardware and software
• Set up a PC to view television signals The PC long ago went well beyond a simple device used to create office documents and
crunch numbers efficiently. With modern PCs, you can experience content on many
levels, from realistic video to scintillating three-dimensional sound. Plus, you can add
the hardware and software to turn the computer into a multimedia creation machine,
making movies and more.
This chapter looks at the many aspects of multimedia available in a modern PC.
First, the chapter discusses how sound works in a PC, both to record and play it back.
Second, you’ll dive into video capture concepts, hardware, and software. Finally, the
chapter rolls through the essentials of setting up the computer to bridge the gap into
the entertainment world fully by installing and configuring TV tuner hardware and
software. Rolling…and…action! Sound
Racing down the virtual track, pixels flying across the screen, hearing the engine roar
as you take another turn and press down the accelerator—or surfing the Web for lovely
scenic nature photos with the sweet, mellifluous music of Mozart filling the room—
sound has become an integral component of the computing experience. Setting up and
optimizing sound for the PC has become an integral skill for all computer techs.
Correctly setting up sound for a PC requires that you know about quite a few things,
because the sound process has many components. You need a properly installed sound
card with the correct drivers loaded, reasonably high-quality speakers, support software
such as the API for a particular game correctly configured in Windows, and a properly
set up application that can use the features of the sound card. And every great tech
needs to know troubleshooting to handle both routine and uncommon problems with
sound. 889 ch20.indd 889 12/9/09 5:12:29 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20 CompTIA A+Certification All-in-One Exam Guide 890 Historical/Conceptual
How Sound Works in a PC
Like the ripples that roll across a pond when you drop a rock in the center, sound flows
from a source in invisible but measurable waves that cause the membranes in your ears
to vibrate and create sound. The sophistication of the human ear enables most people
to differentiate the melodious from the raucous, the loud from the soft. Computers
aren’t nearly as sophisticated as the human ear and brain, so clear standards are a must
for converting music into a format that a PC can use to record and play sound. Computer folks use the terms capture and output instead of record and play. Sound-Capture Basics
Virtually every PC today comes with four critical components for capturing and outputting sound: a sound card, speakers, microphone, and recording/playback software.
Computers capture (record) sound waves in electronic format through a process called
sampling. In its simplest sense, sampling means capturing the state or quality of a particular sound wave a set number of times each second. The sampling rate is measured
in units of thousands of cycles per second, or kilohertz (KHz). The more often a sound
is sampled, the better the reproduction of that sound. Most sounds in the PC world are
recorded with a sampling rate of from 11 KHz (very low quality, like a telephone) to
192 KHz (ultra-high quality, better than the human ear).
NOTE Every modern motherboard comes with sound processing capabilities
built in. By default, techs talk about built-in sound as either built-in sound or
as a sound card, even when there’s no expansion card for sound.
Sounds vary according to their loudness (amplitude), how high or low their tone
(frequency), and the qualities that differentiate the same note played on different instruments (timbre). All the characteristics of a particular sound wave—amplitude, frequency, timbre—need to be recorded and translated into ones and zeroes to reproduce
that sound accurately within the computer and out to your speakers.
The number of characteristics of a particular sound captured during sampling is
measured by the bit depth of the sample, the number of bits used to describe the characteristics of a sound. The greater the bit depth used to capture a sample, the more
characteristics of that sound can be stored and thus re-created. An 8-bit sample of a
Jimi Hendrix guitar solo, for example, captures 28 (256) characteristics of that sound
per sample. It would sound like a cheap recording of a recording, perhaps a little flat
and thin. A 16-bit sample, in contrast, captures 216 (65,536) different characteristics
of his solo and reproduces all the fuzzy overtones and feedback that gave Hendrix his
The last aspect of sound capture is the number of tracks of sound you capture. Most
commonly, you can capture either a single track (monaural) or two tracks (stereo). More
advanced captures record many more sound tracks, but that’s a topic for a more advanced sound capture discussion. ch20.indd 890 12/9/09 5:12:30 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20
All-In-One Chapter 20: Multimedia 891 The combination of sampling frequency and bit depth determines how faithfully a
digital version of a sound captures what your ear would hear. A sound capture is considered CD quality when recorded at 44.1 KHz, with 16-bit depth and in stereo. Most
recording programs let you set these values before you begin recording. Figure 20-1
shows the configuration settings for the Windows Sound Recorder. Figure 20-1
settings Hey, wait a minute! Did you notice the Format setting in Figure 20-1? What’s that?
You can save those sampled sounds in lots of different ways—and that’s where the term
format comes into play. Recorded Sound Formats
The granddaddy of all sound formats is pulse code modulation (PCM). PCM was developed in the 1960s to carry telephone calls over the first digital lines. With just a few
minor changes to allow for use in PCs, the PCM format is still alive and well, although
it’s better known as the WAV format so common in the PC world. WAV files are great for
storing faithfully recorded sounds and music, but they do so at a price. WAV files can be
huge, especially when sampled at high frequency and depth. A 4-minute song at 44.1
KHz and 16-bit stereo, for example, weighs in at a whopping 40-plus MB!
What’s interesting about sound quality is that the human ear cannot perceive anywhere near the subtle variations of sound recorded at 44.1 KHz and 16-bit stereo. Clever
programmers have written algorithms to store full-quality WAV files as compressed
files, discarding unnecessary audio qualities of that file. These algorithms—really nothing more than a series of instructions in code—are called compressor/decompressor
programs or, more simply, codecs. The most famous of the codecs is the Fraunhoffer
MPEG-1 Layer 3 codec, more often called by its file extension, mp3.
NOTE Using MP3 compression, you can shrink a WAV file by a factor of
12 without losing much sound quality. When you compress a WAV file into
an MP3 file, the key decision is the bit rate. The bit rate is the amount of
information (number of bits) transferred from the compressed file to the MP3
decoder in 1 second. The higher the bit rate of an MP3 file, the higher the sound quality.
The bit rate of MP3 audio files is commonly measured in thousands of bits per second,
abbreviated Kbps. Most MP3 encoders support a range of bit rates from 24 Kbps up to
320 Kbps (or 320,000 bits per second). A CD-quality MP3 bit rate is 128 Kbps. ch20.indd 891 12/9/09 5:12:30 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20 CompTIA A+Certification All-in-One Exam Guide 892 WAV and MP3 are only two among a large number of file formats for sound. Not all
sound players can play all of these formats; however, many sound formats are nothing
more than some type of compressed WAV file, so with the right codec loaded, you can
play most sound formats. MIDI
Every sound card can produce sounds in addition to playing prerecorded sound files.
Every sound card comes with a second processor designed to interpret standardized
musical instrument digital interface (MIDI) files. It’s important to note that a MIDI file is
not an independent music file, unlike a WAV file that sounds more or less the same on
many different PCs. A MIDI file is a text file that takes advantage of the sound processing hardware to enable the PC to produce sound. Programmers use these small files to
tell the sound card what notes to play, how long, how loud, on which instruments, and
so forth. Think of a MIDI file as a piece of electronic sheet music, with the instruments
built into your sound card.
NOTE MIDI files have the file extension .MID in the PC world. The beauty of MIDI files is that they’re tiny in comparison to equivalent WAV files.
The first movement of Beethoven’s Fifth Symphony, for example, weighs in at a whopping 78 MB as a high-quality WAV file. The same seven-minute song as a MIDI file, in
contrast, slips in at a svelte 60 KB.
MIDI is hardware dependent, meaning the capabilities and quality of the individual
sound card make all the difference in the world on the sound produced. Sound cards play
MIDI files by using one of two technologies: FM synthesis or wave table synthesis.
FM Synthesis Early processors used electronic emulation of various instruments—
a technique often called FM synthesis—to produce music and other sound effects. Software developers could tell the sound processor to reproduce a piano playing certain
notes, for example, and a sound resembling a piano would pour forth from the speakers. The problem with FM synthesis is that although the modulation sounds okay for a
single note, such as middle C, it sounds increasingly electronic the farther up or down
the scale you go from that prime note.
Wave Table Synthesis To address the odd techno-sound of early sound processors, manufacturers began embedding recordings of actual instruments or other sounds
in the sound card. Modern sound cards use these recorded sounds to reproduce an
instrument much more faithfully than with FM synthesis. When asked to play a C note
on a piano or on a viola, for example, the sound processor grabs a prerecorded WAV
file from its memory and adjusts it to match the specific sound and timing requested.
This technique is called wave table synthesis. The number of instruments a sound card
can play at once is called the polyphony of that card—typically 64 sounds on better cards.
Most modern sound cards have samples of 128 instruments—a veritable symphony
orchestra on a chip! ch20.indd 892 12/9/09 5:12:30 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20
All-In-One Chapter 20: Multimedia 893 NOTE MIDI files are much less popular than other recorded formats on
computers, but every Windows computer and every sound card still fully
supports MIDI. Other File Formats
The WAV, MP3, and MIDI formats may account for the majority of sound files, but
plenty of other less common formats are out there. Here are the extensions of some
other sound file formats you may run into in the PC world:
• AAC Advanced Audio Coding is the native format for songs downloaded into
the Apple iTunes music library. The AAC format is part of the MPEG-4 standard,
offers better compression algorithms than MP3, and is freely distributed. Apple
wraps downloaded songs in a Digital Rights Management (DRM) encapsulation
called FairPlay that gives them control over distribution of those songs.
• AIFF Audio Interchange File Format files are a popular sound format used on
Macintosh computers. These files are often seen at Web sites, and you can use
the well-known QuickTime Player to play them.
• ASM Assembly Language Source files are compressed sound files often seen
on the Internet and used in streaming sound (streaming media is discussed later
in this chapter.)
• ASX Microsoft created the ASX format to facilitate streaming audio over the
Internet through Windows Media Player. It’s more than just a format, though; it
acts like a super playlist and enables you to play other sound file types as well.
The full name of the format is Microsoft Advanced Streaming Redirector.
• AU This popular format is often seen in the Windows world. Many players can
play these files, including players on non-Windows systems, such as Sun, Next,
UNIX, and Macintosh.
• OGG The Vorbis format is an open-source compression codec that competes
well with the proprietary AAC and WMA codecs, as well as MP3. Vorbis files
are saved with the .OGG filename extension, so you’ll hear them (incorrectly)
referred to as “Ogg” files.
• RM RealMedia files play either just audio or audio and video. They are proprietary to RealMedia, a popular player often used on the Internet. You must have
RealMedia Player installed on your computer to play these files.
• WMA Windows Media Audio is Microsoft’s proprietary compression format.
This list scratches the surface of the 100-plus sound file formats available, but it represents those you’re most likely to encounter. Playing Sounds
A large number of programs can play sounds on a typical Windows computer. First, virtually every Windows computer comes with Windows Media Player, possibly the most popular of all sound players. Figure 20-2 shows the default Media Player for Windows Vista. ch20.indd 893 12/9/09 5:12:31 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20 CompTIA A+Certification All-in-One Exam Guide 894 Figure 20-2 Windows Media Player You can download many other players, of course, including iTunes, Apple’s media program
for Windows and OS X. This is good, because not all sound players can play all sounds.
Many applications, especially games, play sounds too. In the not-too-distant past, a
game or an application sometimes had its own sound format, but most applications
and games today use standard WAV, MP3, or MIDI files.
Streaming media is a broadcast of data that is played on your computer and immediately discarded. Streaming media is incredibly popular on the Internet. Streaming
media has spawned an entire industry of Internet radio stations. The three most popular streaming media players are Windows Media Player, Winamp, and Apple’s iTunes.
With the spread of broadband Internet, the quality of streaming radio has improved
dramatically. In fact, it is common to see Internet stations streaming 128 Kbps and
better MP3 files. Some sites even have surround sound music for those who have the
speakers to appreciate it. Essentials
Getting the Right Sound Hardware
Modern motherboards come with built-in sound processing, plus you can buy a sound
card that plugs into a PCI or PCIe expansion slot or into a USB port. Sound cards come
with many features, including two separate sound processors (one for all of the recorded formats such as WAV and another for MIDI), recording capabilities, support for ch20.indd 894 12/9/09 5:12:31 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20
All-In-One Chapter 20: Multimedia 895 MIDI instruments, and more. All sound cards, from the cheapest to the most expensive,
can play music and drive a pair of speakers, so techs need to delve a little deeper to understand the crucial differences among low-, mid-, and high-end sound cards. Sound
cards differ in six basic areas: sound standard, processor capabilities, speaker support,
recording quality, jacks, and extra features.
But the sound card itself is only one part of the equation. You also need good-quality
speakers if you have any intention of listening to music or enjoying some of the more
advanced features such as surround sound.
NOTE The hardware portion of sound-processing equipment in the PC
comes either as a chip built into the motherboard or as an expansion card.
Techs call both forms sound cards, though technically the first type is not
a card at all. Still, the generic term has stuck for the time being. Sound Card Standards
Most sound cards follow one of two standards, AC’97 or Intel High Definition Audio,
although no rule says manufacturers must follow these standards. This applies both to
the sound processing hardware built into motherboards and to add-on sound cards.
The AC’97 standard applies to lower-end audio devices, having been created when
most folks listened to stereo sound at best. Both playback and recording capabilities
of such sound cards offer adequate quality, certainly enough for the typical office PC.
When you want to go beyond average, though, turn to a motherboard or add-on sound
card that offers a newer standard.
Intel designed the Intel High Definition Audio (HDA) standard to support features
such as true surround sound with many discrete speakers. Technically speaking, whereas AC’97 offers support for up to six channels at 48 KHz/20-bit quality, HDA cranks
that up to eight channels at 192 KHz/32-bit quality, a substantial improvement. HDA
also supports sending multiple streams of audio from one computer to different output
devices, so you can enjoy Internet radio in one room, for example, and listen to a CD
in another room, both played on the same computer.
NOTE As they do with new microprocessor models, Intel gave the HDA
standard a codename as well. Look for motherboards offering the Azalia
sound option. That’s Intel High Definition Audio. NOTE Most chipset makers have adopted Intel High Definition Audio for
their better motherboard offerings. That includes direct Intel competitors,
such as NVIDIA. Everybody plays Azalia these days! Processor Capabilities
Sound processor capabilities differ dramatically from the low end to the high end, even
though the prices don’t reflect the great divide. The sound processor handles the communication among the application, operating system, and CPU and translates commands ch20.indd 895 12/9/09 5:12:31 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20 CompTIA A+Certification All-in-One Exam Guide 896 into sounds coming out of the speakers. Low-end sound processors do little more than
translate, which means that the CPU has to do the heavy lifting on the processing front.
Better sound processors, in contrast, shoulder much of the processing burden and
bring a series of extra features to the table. By handling a lot of the processing on board,
these better sound processors free up the CPU for other duties and—in effect and in
name—accelerate the sound process. These decent sound processors also provide excellent sound reproduction, so your MP3s sound as awesome on your PC as they do on
Most mid-range and all high-end sound processors offer support for various surround sound standards, enabling equally equipped games and other applications to
provide positional audio effects and detailed sound modeling—features that make PC
gaming take on a whole new dimension. You’ll learn about the various standards in
detail in the “Speakers” section of this chapter, but for now let an example suffice. With
properly implemented positional audio, when you’re sneaking down the hall, ready to
steal the Pasha’s treasure, you will hear behind you the sounds of the guards marching
up to capture you. Such added realism has many potential benefits beyond games, but
games are currently the primary beneficiary of this technology. Speaker Support
Every sound card supports two speakers or a pair of headphones, but many better
sound cards support five or more speakers in discrete channels. These multiple speakers provide surround sound—popular not only for games but also for those who enjoy
playing DVDs on their PCs. The card shown in Figure 20-3, for example, has outputs
for many speakers. Figure 20-3
A sound card
connections Another popular speaker addition is a subwoofer. A subwoofer provides the amazing
low-frequency sounds that give an extra dimension to all of your sounds, from the surround sound of a game to the music of a simple stereo MP3 file. Almost all modern sound
cards support both surround sound and a subwoofer and advertise this with a nomenclature such as Dolby Digital or DTS. Figure 20-4 shows one type of surround speaker system.
(You’ll learn more about surround sound in the upcoming “Speakers” section.) Recording Quality
Almost every sound card has an input for a powered microphone, but the high-end
cards record with substantially lower amounts of noise or other audible artifacts. The
measure that describes the relative quality of an input port is signal-to-noise ratio and ch20.indd 896 12/9/09 5:12:32 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20
All-In-One Chapter 20: Multimedia 897 Figure 20-4
courtesy of Klipsch
Group, Inc.) is expressed in decibels. The smaller the number, the worse the card is for recording,
because you’re more likely get noise. Most sound cards at the low end and in the mid
range have a signal-to-noise ratio of 30 to 50 decibels, which makes them unacceptable
for recording. High-end cards offer a 96 to 100+ signal-to-noise ratio, a level near what
professional musicians use. Check the documentation before you buy or recommend a
sound card for recording purposes (see Figure 20-5). Figure 20-5
The EMU 1820
112-decibel signalto-noise ratio for
recording. ch20.indd 897 12/9/09 5:12:33 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20 CompTIA A+Certification All-in-One Exam Guide 898 Jacks
Virtually every sound card comes with at least three connections: one for a stereo speaker
system, one for a microphone, and one for a secondary input called line in. If you
look at the back of a motherboard with a built-in sound card, you’ll invariably see
these three connections. On most systems, the main stereo speaker connector is green,
the line in connector is blue, and the microphone connector is pink. You’ll often find
plenty of other connectors as well (Figure 20-6). Figure 20-6
sound card Mini-audio connectors Here’s a list of some of the standard connectors:
• Main speaker out Just what it sounds like, the main speaker output is where
you plug in the standard speaker connector.
• Line out Some cards will have a separate line out connector that is often used
to connect to an external device such as a cassette or CD player. This enables
you to output sounds from your computer.
• Line in The line in port connects to an external device such as a cassette or CD
player to allow you to import sounds into your computer.
• Rear out The rear out connector connects to the rear speakers for surround
sound audio output.
• Analog/digital out The multifunction analog/digital out connection acts as a
special digital connection to external digital devices or digital speaker systems,
and it also acts as the analog connection to center and subwoofer channels. (See
the “Speakers” section later in this chapter for a discussion of surround sound.)
voice input. The microphone port connects to an external microphone for • Joystick The now-obsolete joystick port connects a joystick or a MIDI device
to the sound card. The joystick port is a two-row, DB15 female connection, but
few motherboards or sound cards include the port these days. ch20.indd 898 12/9/09 5:12:33 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20
All-In-One Chapter 20: Multimedia 899 Extra Features
With all motherboards including built-in sound these days, expansion sound card
makers have responded by adding a host of extra goodies and capabilities to their cards
that, for some folks, prove irresistibly tempting. These include a digital output to integrate the PC with a home entertainment unit, DVD receiver, and surround sound
speaker connection capabilities; a breakout box that adds recording and output ports
in a 5.25-inch bay; and a FireWire connection for direct gaming, file sharing, and immediate MP3 playing from a portable MP3 device. Figure 20-7 shows a version of the
Creative Labs SoundBlaster breakout box. These features aren’t for everyone, but they
are compelling to many consumers.
Breakout box for
sound card Speakers
It always blows me away when I walk into someone’s study and hear tinny music whining from a $10 pair of speakers connected to a $2000 computer. If you listen to music
or play games on your computer, a decent set of speakers can significantly improve the
experience. Speakers come in a wide variety of sizes, shapes, technologies, and quality
and can stump the uninformed tech who can’t easily tell that the $50 set on the right
sounds 100 times better than the $25 pair on the left (Figure 20-8).
another manufacturer’s low-end
speaker set (left) ch20.indd 899 12/9/09 5:12:34 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20 CompTIA A+Certification All-in-One Exam Guide 900 Speaker Standards The advent of surround sound in the computing world has
created a number of speaker standards. You should know these standards so you can
choose the speakers that work best for you and your clients.
Stereo is the oldest speaker technology you’ll see in the PC world. Stereo speakers
are just what you might imagine: two speakers, a left and a right (Figure 20-9). The two
speakers share a single jack that connects to the sound card. Most cheap speakers are
Stereo speakers A 2.1 speaker system consists of a pair of standard stereo speakers—called satellites—
combined with a subwoofer (Figure 20-10). The average 2.1 speaker system has a single
jack that connects to the sound card and runs into the subwoofer. Another wire runs
from the subwoofer to the two stereo speakers. If you want to enjoy great music and
don’t need surround sound, this is your speaker standard of choice.
speakers ch20.indd 900 12/9/09 5:12:35 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20
All-In-One Chapter 20: Multimedia 901 Going beyond standard two-channel (stereo) sound has been a goal in the sound
world since the 1970s. However, it wasn’t until the advent of Dolby Laboratory’s Dolby
Digital sound standard in the early 1990s that surround sound began to take off. The
Dolby Digital sound standard is designed to support five channels of sound: frontleft, front-right, front-center, rear-left, and rear-right. Dolby Digital also supports a
subwoofer—thus, the term 5.1. Another company, Digital Theatre Systems (DTS), created a competing standard that also supported a 5.1 speaker system. When DVDs were
introduced, they included both Dolby Digital and DTS 5.1 standards, making 5.1 speakers an overnight requirement for home theater. If you want to enjoy your DVDs in full
surround sound on your PC, you must purchase a full 5.1 speaker system. A number of
5.1 speaker systems are available for PCs. The choice you make is usually determined
by what sounds best to you.
Many sound cards also come with a special Sony/Philips digital interface (S/PDIF)
connector that enables you to connect your sound card directly to a 5.1 speaker system
or receiver (Figure 20-11). Using a single S/
PDIF instead of a tangle of separate wires
for each speaker greatly simplifies your
sound setup. S/PIDF connections come in
two types, optical and coaxial. The optical variety looks like a square with a small
door (at right in Figure 20-11). The coaxial
is a standard RCA connector (at left), the same type used to connect a CD player to your
stereo. It doesn’t matter which one you use; just make sure you have an open spot on
your receiver or speakers.
NOTE Only a few 5.1 PC speaker sets come with S/PDIF. In most cases,
you’ll have to use the regular audio outputs on the sound card. You’ll find the
connector more common on 6.1 and 7.1 sets.
Games can also take advantage of 5.1, 6.1, and 7.1 speakers, but they use the DirectX
standard. DirectX offers numerous commands, also known as APIs, that issue instructions such as “make a sound on the right speaker” or “play music in both the right and
left channels.” DirectX simplifies the programming needed to create sound and video:
rather than having to program sounds in different ways for each sound card option,
games can talk DirectX. The hardware manufacturers simply have to ensure that their
sound cards are DirectX compatible.
DirectX version 3 introduced DirectSound3D (DS3D), which offered a range of commands to place a sound anywhere in 3-D space. Known as positional audio, it fundamentally changed the way most PC games were played. DS3D could not handle all sound
information, but it supported extensions to its instructions for more advanced sound
features. This challenged the sound card designers to develop more fully the concept of
positional audio. Creative Labs responded by rolling out environmental audio extensions
(EAX), a set of audio presets that gave developers the capability to create a convincing
sense of environment in entertainment titles and a realistic sense of distance between
the player and audio events. Figure 20-12 shows an EAX setup screen. ch20.indd 901 12/9/09 5:12:35 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20 CompTIA A+Certification All-in-One Exam Guide 902 Figure 20-12
EAX setup screen In late 2000, a number of EAX effects were incorporated into the DirectX audio
component of DirectX 8.0. This signaled the acceptance of EAX as the standard for
audio effects in gaming. Shortly afterward, Creative Labs started releasing audio cards
that were Dolby 5.1 compatible out of the box. This let you plug a 5.1 speaker system
directly into your sound card. The sound card automatically decoded the Dolby/DTS
sound track when you played a DVD and the EAX effects when you played a game that
supports it. All current sound cards support DirectX and EAX.
NOTE Not all cards support Dolby Digital/DTS. Most software DVD players
and some sound cards support Dolby Digital. DTS support is a little harder
to come by. Check the manufacturer’s Web site to determine whether your
card will work with DTS.
Microsoft changed the way audio works in Windows Vista from the way it works
in previous versions of Windows. Most notably, Vista doesn’t support direct hardware
access to sound, so DirectSound does not work. Third-party developers have created
various workarounds for this lack of support to enable some older games and hardware
to function in Windows Vista. Other developers have gotten behind the OpenAL API to
provide environmental audio effects in Vista. Specific OpenAL drivers for games have
to be included to provide that support.
Speaker Features Speakers also come with a few other features that you should
consider when choosing a set for yourself or your clients. Speakers offer a variety of
power sources, controls accessibility, and headphone jacks. ch20.indd 902 12/9/09 5:12:36 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20
All-In-One Chapter 20: Multimedia 903 Most speakers have volume controls as well as an on/off switch. Get a system that
provides easy access to those controls by placing them on an easy-to-reach speaker or
on a special control box.
The problem with headphones is that you need to plug them into the back of the
sound card and then tell Windows to output to them from the Sound applet on the
Control Panel. Save yourself a lot of hassle and get a speaker system that has a handy
microphone jack on one of the speakers or on a control box. Installing Sound in a Windows System
You’ve got two choices for sound hardware on today’s PCs: a separate sound card or onboard sound built into the motherboard. The installation process for a sound card is basically the same as the process for any other card. You snap the card into a slot, plug some
speakers into the card, load a driver—and for the most part, you’re finished. With onboard
sound, you need to make sure the sound is enabled in your CMOS and then load the
driver. As with most of the devices discussed in this book, sound card installation consists
of three major parts: physical installation, device driver installation, and configuration. Physical Installation
Physical installation is easy. Onboard sound is already physically installed and most
sound cards are run-of-the-mill PCI cards (Figure 20-13), although you can find PCIe
and USB versions too. The real trick to physical installation is deciding where to plug in
the speakers, microphone, and so on. The surround sound devices so common today
feature a variety of jacks, so you will probably want to refer to your sound card documentation for details, but here are a few guidelines:
card • The typical stereo or 2.1 speaker system will use only a single jack. Look for the
jack labeled Speaker or Speaker 1. ch20.indd 903 12/9/09 5:12:36 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20 CompTIA A+Certification All-in-One Exam Guide 904 • Surround speakers either use a single digital (S/PDIF) connection, which in
most cases runs from the sound card to the subwoofer, or they need three separate cables: one for the front two speakers that runs to the Speaker 1 connector,
one for the back two speakers that runs to the Speaker 2 connector, and a third
cable for the center channel and subwoofer that runs to the digital/audio out or
Speaker 3 connector.
Here’s a quick look at sound card installation. As with any expansion card, you’ll
need a Phillips-head screwdriver to install a sound card, as well as your electrostatic discharge (ESD) prevention equipment. Of course, you’ll also need the sound card itself,
a set of speakers, an audio cable if it’s an older system, and a microphone if you want
to be able to record sounds.
1. Shut down your computer, unplug it, and open the case.
2. Find an open PCI or PCIe slot and snap in the sound card. Remember to handle
the card with tender loving care—especially if you’re installing an expensive,
high-end card! Make sure the card is securely seated, and secure it to the chassis
with a hex screw. Installing Drivers
Once the sound card is installed, start the system and let Windows install the card’s
drivers. This applies to expansion cards and onboard sound. As you might expect
by now, you’ll probably have a choice between the built-in Windows drivers and
the driver that comes on a CD-ROM with your sound card. Just as with other cards,
it’s always best to install the driver that comes with the card. All sound devices have
easy-to-use autorun-enabled installation CD-ROMs that step you through the process
(Figure 20-14). Figure 20-14
screen for a
sound card ch20.indd 904 12/9/09 5:12:37 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20
All-In-One Chapter 20: Multimedia 905 NOTE Sound card drivers are updated occasionally. Take a moment to check
the manufacturer’s Web site to see whether your sound card has any driver
You might run into one of the USB sound cards out on the market (Figure 20-15), in
which case the installation process is reversed. The only secret to these devices is to follow the important rule of all USB devices: Install the drivers before you plug in the device.
Windows, especially Windows XP and Vista, probably have basic drivers for these USB
sound cards, but don’t take a chancealways install the drivers first. Figure 20-15
USB sound card After your sound card and driver are installed, make a quick trip to the Device Manager to ensure that the driver was installed correctly, and you’re two-thirds of the way
there. Installing the driver is never the last step for a sound card. Your final step is to
configure the sound card by using configuration programs and test it by using an application. Most sound cards come with both special configuration programs and a few
sound applications on the same CD-ROM that supplies the drivers. Take a look at these
extra bits of software that I call sound programs. Installing Sound Programs
You’ve already seen that you need a program to play sounds on your PC: Windows
Media Player, Winamp, or something similar. But several other classes of sound programs also reside on your computer: programs for the configuration of your sound
card—tools built-into Windows as well as proprietary tools—and special applications
that may or may not come with your sound card.
Windows Configuration Applications Every Windows computer comes
with at least one important sound configuration program built right into the operating
system: the Control Panel applet called Sound in Windows Vista, Sounds and Audio
Devices in Windows XP, or Sounds and Multimedia in Windows 2000. Whatever the
name, this applet (or applets) performs the same job: it provides a location for performing most or all of the configuration you need for your sound card. Consider the ch20.indd 905 12/9/09 5:12:38 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20 CompTIA A+Certification All-in-One Exam Guide 906 Sounds and Audio Devices applet in Windows XP, for example; the Sounds and Multimedia applet in Windows 2000 works roughly the same, although it may have one
control or another in a different place.
The Sounds and Audio Devices applet has five tabs: Volume, Sounds, Audio, Voice,
and Hardware. The Volume tab is the most interesting. This tab adjusts the volume for
the speakers, and it allows you to set up the type of speaker system you have, as shown
in Figure 20-16. Figure 20-16
dialog box The Sounds tab allows you to add customized sounds to Windows events, such as the
startup of a program or Windows shutdown. The Audio tab (Figure 20-17) and Voice
tab do roughly the same thing: they allow you to specify the device used for input and
output of general sounds (Audio tab) and voice (Voice tab). These settings are handy for
folks like me who have a regular microphone and speakers but also use a headset with
microphone for voice recognition or Internet telephone software. By telling Windows
to use the microphone for normal sounds and to use the headset for voice recognition,
I don’t have to make any manual changes when I switch from listening to an MP3 to
listening to my brother when he calls me over the Internet.
The Hardware tab isn’t used very often, but it does have one interesting feature: it
shows you all of the audio and video codecs installed in your system. (See the section
on “Missing Codecs” later in this chapter for more details on codecs.) ch20.indd 906 12/9/09 5:12:38 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20
All-In-One Chapter 20: Multimedia 907 Figure 20-17
Audio tab Microsoft changed a few things between Windows XP and Windows Vista when it
comes to configuring sound. The Sound applet offers better support for multiple speaker
setup, for example, and integration with television with HDMI configuration options.
To configure speakers, go to Control Panel and click Hardware and Sound; then click
Sound if in Category View or double-click the Sound applet if in Classic View. Either
route opens the Sound applet (Figure 20-18).
Sound applet in
Windows Vista ch20.indd 907 12/9/09 5:12:38 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20 CompTIA A+Certification All-in-One Exam Guide 908 Select the Speakers option and click the Configure button to open the Speaker Setup
dialog box (Figure 20-19). Select the audio channel option that’s appropriate for your
setup, such as the 5.1 system selected for my setup at the office and shown in Figure 20-19.
You can click on individual speaker icons to test if the speakers are set up properly, or click
the Test button to cycle through the whole range of speakers. Figure 20-19
dialog box in
Windows Vista Proprietary Configuration Applications Many sound cards install proprietary software to support configuration features not provided by Windows. Figure 20-20
shows one such application. This special configuration application comes with Creative
Labs sound cards to add a few tweaks to the speaker setup that the Sounds and Audio
Devices applet doesn’t support.
Most sound cards come with some form of configuration program that works with
the Control Panel applet to tweak the sound the way you want it. Figure 20-21 shows
the applet that came with my motherboard. One of its many interesting features is to
detect what types of devices are installed into the sound ports and adjust the system to
use them. In other words, I don’t even have to look where I’m plugging in anything! If I
plug a microphone into the front speaker port, the system just adjusts the outputsvery
cool. Software and sound cards that can do this are called autosensing.
Take some time to experiment with the program that comes with your sound card—
this is a great way to learn about some of the card’s features that you might otherwise
not even know are there! ch20.indd 908 12/9/09 5:12:39 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20
All-In-One Chapter 20: Multimedia 909 Figure 20-20
Headphone panel Figure 20-21
connected devices Specialized Applications Some sound cards—Creative Labs sound cards are by
far the most infamous for this—install one or more applications, ostensibly to improve
your sound experience. These are not the configuration programs just described. These
applications enable you to do anything from composing music to organizing your
sound files. Personally, I don’t have much use for an application such as the 3DMIDI
Player (Figure 20-22)—but you might be just the type of person who loves it. Be sure
at least to install the applications that come with your card. If you don’t like them, you
can easily uninstall them. ch20.indd 909 12/9/09 5:12:39 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20 CompTIA A+Certification All-in-One Exam Guide 910 Figure 20-22 Creative Labs 3DMIDI Player program Practical Application
The problems you’ll run into with sound seem to fall into one of two camps: those that
are embarrassingly simple to repair and those that defy any possible logic and are seemingly impossible to fix. This section divides sound problems into three groups—hardware,
configuration, and application problems—and gives you some ideas on how to fix
these problems. Hardware Problems
Hardware problems are by far the most common sound problems, especially if your
sound card has worked for some amount of time already. Properly installed and configured sound cards almost never suddenly stop making sounds.
Volume The absolute first item to check when a sound dies is the volume controls.
Remember that you can set the volume in two places: in software and on the speakers. ch20.indd 910 12/9/09 5:12:40 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20
All-In-One Chapter 20: Multimedia 911 I can’t tell you the number of times I’ve lost sound only to discover that my wife turned
down the volume on the speakers. If the speaker volume is okay, open the volume
controls in Windows by clicking the little speaker icon on the system tray, and make
sure that both the master volume and the volume of the other controls are turned up
(Figure 20-23). Figure 20-23
in Windows XP NOTE If your system tray (i.e., the notification area) is cluttered and the little
speaker icon hard to find, you can access the Play Control dialog box by
opening the Sounds and Audio Devices applet in the Control Panel. On the
Volume tab—the one that’s on top by default—click the Advanced button
under Device volume.
If you don’t have a little speaker in your system tray at all in Windows XP, you can add
it. Just check the box next to the Place volume icon in the taskbar option in the Sound and
Audio Devices Properties dialog box, Volume tab. Presto!
Speakers The second place to look for sound problems is the speakers. Make sure
the speakers are turned on and are getting good power. Then make sure the speakers
are plugged into the proper connection on the back of the sound card. If this all checks
out, try playing a sound, using any sound program. If the sound program looks like it is
playing—maybe the application has an equalizer that is moving or a status marker that
shows that the application is playing the sound—you may have blown speakers. Try
another pair and see if the sound returns.
Most of the time, speakers come in a matched set—whether it’s a 2.1, 4.1, 5.1, or
other system—and the manufacturer includes adequate connecting wires for the whole
set. On occasion, you might run into a system in which the user has connected pairs of
speakers from different sets or rigged a surround sound system by replacing the stock
wires with much longer wires. Either option can create a perfectly functional surround
sound system that works for a specific room, but you should make sure that all the
speakers require the same wattage and that high-quality wire is used to connect them. ch20.indd 911 12/9/09 5:12:40 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20 CompTIA A+Certification All-in-One Exam Guide 912 If you troubleshoot a system in which two of the speakers are very quiet and two are
very loud, the wattages are probably different between the two pairs. A simple check of
the labels should suffice to troubleshoot, or you can swap out one pair for a different
pair and see if that affects the volume issues. Cheap wire, on the other hand, simply
degrades the sound quality. If the speakers sounded good before being strung on long
wires but they now have a lot of low-grade noise, blame the wires. Configuration Problems
Configuration errors occur when the sound card is physically good but some setting hasn’t
been properly configured. I also include drive problems in this category. These errors happen almost exclusively at installation, but they can appear on a working system, too.
NOTE Technically speaking, turning down the volume in the volume control
program isn’t a configuration problem; it’s just something I always check at
the same time I check the volume on the speakers.
The first place to check is the Device Manager. If the driver has a problem, you’ll see
it right there. Try reinstalling the driver. If the driver doesn’t show any problems, again
try playing a sound and see if the player acts as though the sound is playing. If that’s the
case, you need to start touring the Sound applet or Sounds and Audio Devices applet to
see if you’ve made a configuration error—perhaps you have the system configured for 5.1
when you have a stereo setup, or maybe you set the default sound output device to some
other device. Take your time and look—configuration errors always show themselves. Application Problems
Application problems are always the hardest to fix and tend to occur on a system that
was previously playing sounds without trouble.
First, look for an error message (Figure 20-24). If an error code appears, write it
down exactly as you see it and head to the program’s support site. Odds are very good
that if you have the error text, you’ll get the fix right away from the support site. Of
course, you can always hope the built-in help has some support, but help systems tend
to be a little light in providing real fixes.
message Don’t always blame the sound application—remember that any sound file might be
corrupted. Most sound players will display a clear error message, but not always. Try
playing the sound file with a different application.
Last, a good approach almost always is to reinstall the application. ch20.indd 912 12/9/09 5:12:40 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20
All-In-One Chapter 20: Multimedia 913 Video Capture
A microphone, sound card, and software enable you to capture audio, but with a camera capable of capturing full motion video as well as sound, you can turn the PC into
your very own movie studio. This is called video capture. To capture video from a source
requires you to have the proper hardware installed to provide an interface with the
camcorder or video player and, if the source is analog, provide translation of the signal
as well; plus you need a properly configured application to do the capturing. Once captured, you can use an application to edit the video file. Then save it in some form for
upload a la YouTube or save it to DVD or other removable media. Hardware
You need the proper hardware installed to capture video. From a digital signal, such as
a modern camcorder that records directly to its own internal solid state hard drive, you
simply run a cable from the FireWire out port on the camcorder to the FireWire port on
your computer. If the camcorder doesn’t offer FireWire, it’ll most likely use Hi-Speed
USB. When capturing from an analog source, such as a VHS cassette player or a Hi-8
tape, you’ll need some kind of connection and translation hardware.
The Pinnacle blueBox pictured in Figure 20-25, for example, offers two different
dedicated video connections (S-Video on the left and the yellow RCA jack next to it),
stereo RCA audio jacks, plus a FireWire port (on the expansion card for it) for direct
connection to FireWire onboard the camcorder. The breakout box uses a proprietary
connection to plug into the PC.
A video capture
device NOTE The FireWire connection seems redundant—just go straight to
FireWire on the PC, right? But it’s there to accomplish two goals. First, many
PCs don’t have a FireWire port, so you would either need to add a FireWire
expansion card or use a different type of port. Second, Sony produced a
series of Hi-8 camcorders some years ago that had a FireWire connector. Some translation
has to happen to turn the analog signal digital.
You need a decent-grade computer with lots of free hard drive space and a substantial amount of RAM to import the video and audio streams from an external source. ch20.indd 913 12/9/09 5:12:41 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20 CompTIA A+Certification All-in-One Exam Guide 914 And you’ll certainly need a serious processor when it comes time to edit and compile
a new video from the source material. There’s no simple rule for how much of any resource you’ll need. Different projects have different demands on the hardware. If you’re
setting up a new computer for video capture, the simple rule is to get as powerful a
system as possible with as much hard drive and RAM capacity as you can afford.
Once you have the hardware in place, the true heavy lifting in video capture falls on
the software. Software
With video editing applications, such as Pinnacle Studio or Apple Final Cut, you can
import video and then work with it directly. Figure 20-26 shows the former software
capturing video and audio translated through the Pinnacle blueBox from a Hi-8 camcorder. Most webcams—even those built into portable computers—are analog, rather
than digital devices. Thus some software automatically creates break points in the import to make the editing process easier. Figure 20-26 Importing video in Adobe Premier Elements The video editing software enables you to take video and audio from one or many
sources and arrange clips into a time line. You can add and edit various transitions between clips, shorten clips, and so on. Figure 20-27 shows the storyboard from Final Cut
Pro and a how-to video my team produced in-house. ch20.indd 914 12/9/09 5:12:42 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20
All-In-One Chapter 20: Multimedia 915 Figure 20-27 Editing in Final Cut Pro Once you’ve finished the editing process, you can export to a file for archiving, sending out on optical disc, or posting to a video sharing site. With an audio file, as discussed earlier, this is a simple process. You pick a format such as MP3 and save the file.
Video is far more complicated.
A video is two or more separate tracks—moving picture and audio—that each go
through a compression algorithm. Otherwise, the resulting files would be huge, even
for short videos. The compressed tracks then get wrapped up into a container file, what’s
often called a wrapper. When you receive a file saved in a standard wrapper, such as .MOV
for a QuickTime Movie file, you have no way to know for certain which codecs were used
to compress the video or audio tracks inside that container file (Figure 20-28). Figure 20-28
tracks, each encoded separately. ch20.indd 915 12/9/09 5:12:43 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20 CompTIA A+Certification All-in-One Exam Guide 916 Codecs
Video files use standard audio codecs for the audio tracks, such as WAV or MP3, but
vary wildly in the type of video codecs used. Just as with audio codecs, video codecs
take a video stream and compress it by using various algorithms. Here are some of the
standard video codecs.
• MPEG-2 Part 2, used for DVDs
• MPEG-4 Part 2, a codec often used for Internet broadcasts; you’ll find implementations of it with other names, such as DivX
• H.264, used for high-definition movies for Blu-ray Discs, among others
• Windows Media Video (WMV), the family of Microsoft-developed codecs
• Theora, an open-source codec developed to go with the Vorbis audio codec as
part of the Ogg project
• TrueMotion VP6, used in Adobe Flash; and VP7, used for Skype video conferencing, among others
• VC-1 is a Microsoft-designed codec that competes with H.264 and other higherend codecs for the hearts and minds of Blu-ray Disc developers. You’ll usually
find it wrapped in a WMV container file (see the following section). Wrappers
When both the video and audio streams of your video file are compressed, the file is
placed into some sort of container file or wrapper. The key thing to note here is that the
wrapper file doesn’t necessarily specify how the video or audio tracks were encoded.
You can look at two seemingly identical movie files, for example, both saved with the
.MOV file extension, and find that one will play audio and video just fine in Windows
Media Player, but the other one might play only the audio and not the video because
Media Player lacks the specific codec needed to decode the video stream. (More on this
in the “Troubleshooting” section.) Here are some of the standard video wrappers.
• ASF, a container used mainly for WMA and WMV streams; note that you can
also have a WMV wrapper for a WMV-format file.
• AVI, the standard container file for Windows
• Flash Video (.FLV) contains streams encoded with various codecs, such as
H.263 or VP6; can also handle H.264 codec. Flash Video has become the dominant standard for displaying video content on the Web through places such as
YouTube and Hulu.
• MOV, the standard container file for Apple QuickTime for both Macintosh OS X
• MPEG-2 Transport Stream (MPEG-TS), a container for broadcasting that can
handle many streams
• Ogg, a container file made for the open source Vorbis and Theora codecs ch20.indd 916 12/9/09 5:12:44 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20
All-In-One Chapter 20: Multimedia 917 Troubleshooting
Video capture and playback suffer from several quirks. On the capture side, you’ll find
dropped frames, problems synchronizing video and audio when capturing content
from an analog device, and generally poor quality captures. On the playback side, the
only real issue is missing codecs. Dropped Frames
Many things cause an initial capture to drop frames, the end result of which is loss of
video information and choppy playback. This happens with both analog and digital
sources, so it’s not necessarily a conversion issue, and it’s maddeningly common.
The most common fix for dropped frames is to turn stuff off. Some of this is obvious. If you’re surfing the Web or doing instant messaging while trying to capture video,
you’ll drop frames with wild abandon. Don’t do it. In fact, disconnect the computer
completely from the Internet so no traffic happens in the background. Only do video
capture on that machine and use another computer if you need to multitask.
Often the viewing of content you’re capturing—while in the capture process—causes
dropped frames. Best practice is to know what you’re importing, turn off the playback
or preview feature, and then start the capture. But the obvious programs aren’t necessarily the primary cause of dropped frames.
Windows is a wildly extensible operating system, and programmers love to dump
helper applications to run in the background to optimize their specific application.
Install Apple’s iTunes, for example, and you’ll get more than you bargained for in programs installed. To go along with the iTunes player, the installation puts in automatic
update-checking tools, iPod helpers, a quick-launch for QuickTime, and more.
The best solution is to have a machine dedicated to video capture. If you have a
machine with multiple functions, however, you can turn off some of the automatically
loading helper applications before you start the video capture process. You do this by
stopping processes and services through the Task Manager.
In Windows Vista, get to the Task Manager by pressing CTRL + SHIFT + ESC or by pressing
CTRL + ALT + DELETE and clicking the Start Task Manager option. The Processes tab shows
your running processes. You can right-click any unnecessary process and close it by selecting End process or End process tree from the context menu (Figure 20-29). I generally
go for the latter option, just in case some other process is running only because of the
unnecessary process. That gets them all.
Once you’ve stopped processes, click over to the Services tab. You can quickly see
what’s running, by sorting services by status. Just click the Status column heading to
sort. Right-click any unnecessary service and select Stop Service from the context menu
(Figure 20-30). Couldn’t be easier!
If you find you’ve stopped a necessary service, you can simply right-click it again
and select Start Service from the context menu. Or, if the system has become unstable,
a simple reboot will reload everything.
NOTE You can disable services in the Services applet in Administrative
Tools, but it’s usually better to stop a service first through Task Manager,
just to see if it’s truly unnecessary for system stability or function. ch20.indd 917 12/9/09 5:12:44 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20 CompTIA A+Certification All-in-One Exam Guide 918 Figure 20-29 Ending a process Figure 20-30
Stopping a service ch20.indd 918 12/9/09 5:12:45 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20
All-In-One Chapter 20: Multimedia 919 Sync Problems
Capturing a video and audio stream simultaneously can be tough, because it takes
the computer a lot longer to encode the video than the audio stream. This can lead to
significant disconnection between the video and audio streams, so they become desynchronized. It’s surprisingly easy to create a movie that’s very badly lip-synced! The
process of synchronizing audio and video is called A/V sync.
NOTE There’s also a common problem of video and audio going out of sync
in the process of burning from a hard drive to a DVD, but that’s a distinctly
different problem than a lack of A/V sync in the capture process.
You can fix this problem sometimes by changing software or even versions of software. Alternatively, if you’re having problems with an analog capture, you can record
the analog signal into a digital video camcorder and then try to capture from the digital
device. A bit clunky, perhaps, but it can work. Finally, you do the last solution in processing, where you manually separate the audio and video streams and then put the
whole thing back together synced properly.
Dealing with video capture can be difficult and time consuming, especially in the
analog to digital process. A good resource to start learning the detailed ins and outs is
with the folks at the Digital FAQ: www.digitalfaq.com. Poor Capture Quality
Numerous factors can degrade the quality of a video capture, including background
programs, marginal hardware for the job, and poor quality source materials. For the
background program issue, follow the same procedures as you did above with the
dropped frames. If the computer or the capture components can’t do the job, the only
fix is to upgrade. The best things to upgrade are the capture hardware and the CPU. It
goes almost without saying that you’ll need gobs of RAM too.
EXAM TIP A dedicated A/V computer should have a fast processor and a lot
of RAM. You’ll want plenty of hard drive storage space too.
There’s very little you can do if your source material, such as an old video cassette,
has degraded. You’re simply not going to get a pristine capture from a damaged source.
You can sometimes get better quality by having the heads on the camcorder or player
cleaned or by using the camcorder on which the tape was initially recorded. Missing Codecs
All versions of Windows come with some audio and video codecs installed. The default audio codecs will handle most common music formats, though you’ll need to
download the Vorbis codec if you want to use that format. Video codecs are a different
The first clue you might have that your computer doesn’t have the codec to process a
video file properly is that the sound will play but no picture will appear. Occasionally, ch20.indd 919 12/9/09 5:12:45 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20 CompTIA A+Certification All-in-One Exam Guide 920 whatever media player you use will tell you that it’s missing a video codec and attempt
to go out onto the Internet to download a codec automatically. You can also download
a codec or set of codecs manually.
Windows XP makes it easy to see the installed codecs. In Control Panel, open the
Sounds and Audio Devices applet. Select the Hardware tab | Audio Codecs and click the
Properties button. In the Audio Codec Properties dialog box, select the Properties tab
and you’ll see all the installed audio codecs (Figure 20-31). Figure 20-31
Windows XP SP2 Similarly, you can see the video codecs by choosing the Video Codecs option on the
Hardware tab. Click through to the Properties tab. Figure 20-32 shows the default video
codecs in Windows XP.
Microsoft made the codecs a bit more difficult to find in Windows Vista. In Vista,
open Windows Media Player. Press CTRL-M to show the classic menus. Select Help |
About Windows Media Player to open the About Windows Media Player dialog box
Click the link for Technical Support Information and Windows will open your default Web browser with a long page showing various multimedia settings. Scroll down
the page and you’ll find the audio and video codecs installed (Figure 20-34).
If you don’t have a codec that you need, you can download that specific codec.
A great site for codec information is www.fourcc.org. ch20.indd 920 12/9/09 5:12:46 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20
All-In-One Chapter 20: Multimedia 921 Figure 20-32
Windows XP SP2 Figure 20-33
dialog box in
Windows Vista You can also download codec packs, such as the Vista Codec Package available at
www.afreecodec.com. The packs contain just about everything you need to view and
hear content found on the Internet. ch20.indd 921 12/9/09 5:12:46 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20 CompTIA A+Certification All-in-One Exam Guide 922 Figure 20-34 Viewing audio and video codecs installed in Windows Vista TV Tuners
With a TV tuner, you can have it all in one package: a computer and the latest TV show as
well. Most local stations (in the United States, at least) broadcast high-definition signals,
so with the proper TV tuner, you can watch your HDTV without any of the artifacting
you see with both cable and satellite feeds. Plus you can make use of typical cable or
satellite feeds to watch television as you would with a regular TV. To make it all happen
requires four components: a tuner device, an antenna or cable connection, a tuning application, and some sort of program guide. We’ll look at troubleshooting at the end. Tuner Hardware
TV tuners come in just about every expansion option available for computers: expansion
cards that plug into PCI or PCIe slots on the motherboard; PC Card or ExpressCard for
portable computers; or Hi-Speed USB for desktop and laptop computers. Figure 20-35
shows a PCIe version of an ATI tuner card.
To install a TV tuner, follow standard installation procedures. ch20.indd 922 12/9/09 5:12:46 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20
All-In-One Chapter 20: Multimedia 923 Figure 20-35
ATI TV tuner card NOTE TV tuners often include components for video capture, so you can
get both devices on one card or expansion device. To pick up a signal on the TV tuner, just as with a standalone television, you need
some source. Most can handle a cable TV connection, for example, or an over-the-air
antenna. Figure 20-36 shows a USB Hauppauge HDTV tuner card with retractable antenna. For such a small device, it picks up HDTV signals quite well. You’ll get the best
results for uncompressed HD signals by using a serious, mounted-on-the-rooftop metal
antenna with lots of tines.
tuner with retractable antenna Tuner hardware comes with a standard coaxial connection. You can plug in a cable
or satellite source just as you would any regular television. ch20.indd 923 12/9/09 5:12:48 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20 CompTIA A+Certification All-in-One Exam Guide 924 Tuner Software
Once you’ve installed the hardware, you need to load the specific application or applications that make the tuner work as a tuner. If you have a copy of Windows Media
Center (through either that version of Windows XP or Windows Vista Ultimate), that
will often be the tool of choice. Tuner card distributors bundle third-party applications
with their cards. Figure 20-37 shows the EyeTV software enabling the computer to show
television shows. Figure 20-37
application Tuner Troubleshooting
The two biggest issues with TV tuner devices are operating system compatibility and poor
reception. Some cards simply don’t work with Windows Vista, due to driver incompatibility or some other issue. The only fix for this problem is to use one that does work.
The antenna that comes with your tuner should enable you to pick up TV broadcasts
in most places, certainly around cities. But a small sliver of metal can only do so well,
so you’ll experience stuttering, essentially lost frames that may or may not make the
program you’re viewing viewable. So an antenna used primarily for portable computing, such as the telescoping model pictured in Figure 20-36, is great, but if you install
a tuner in a static computer, consider investing in a proper outdoor antenna. Beyond A+
Sound Card Benchmarking
Sound cards can demand a huge share of system resources—particularly CPU time—
during intense work (such as gaming). Most techs who find an otherwise serviceable PC stuttering during games will immediately blame the video card or the video ch20.indd 924 12/9/09 5:12:48 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20
All-In-One Chapter 20: Multimedia 925 card drivers. What they don’t realize is that sound cards can be the cause of the problem. A test of a client’s built-in audio, for example, revealed that at peak usage the
sound card took more than 30 percent of the CPU cycles. Thirty percent? Holy smokes!
And he wondered why his system bogged down on yesterday’s games! He could just
forget about playing Crysis.
The folks at http://audio.rightmark.org make an excellent suite of sound card benchmarking utilities that helps you analyze the particulars of any sound card: RightMark
3DSound (Figure 20-38). It will run a system through fairly serious tests, from regular
sound to 3-D positional audio, and reveal whether or not the sound processor—built-in
or expansion card—is causing a problem with resource use. You can find the utility at
http://audio.rightmark.org. Figure 20-38
3DSound ch20.indd 925 12/9/09 5:12:49 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20 CompTIA A+Certification All-in-One Exam Guide 926 Chapter Review Questions
1. What refers to the number of characteristics of a particular sound captured
A. Sample rate
C. Bit depth
D. Quality rating
2. All recorded sound formats used in PCs today are derived from which format?
3. Which sound format contains no actual sound recording but only a series of
commands stored in a text file for the sound card to interpret?
4. How many speakers are in a Dolby Digital 5.1 setup?
A. Five speakers plus a subwoofer
B. Six speakers plus a subwoofer
C. Seven speakers plus a subwoofer
D. Eight speakers plus a subwoofer
5. What is the name of the extensions to the DirectSound3D standard developed
by Creative Labs?
C. Positional audio
6. What is the name of the standard digital connection that replaces many analog
connections on some sound cards?
A. CD audio connector
B. AUX connector
C. TAD connector
D. S/PDIF connector ch20.indd 926 12/9/09 5:12:49 PM All-In-One / CompTIA Network+ All-in-One Exam Guide / Meyers & Jernigan / 170133-8 / Chapter 20
All-In-One Chapter 20: Multimedia 927 7. Which sampling rate would produce the highest quality sound?
A. 8 Hz
B. 8 KHz
C. 128 Hz
D. 128 KHz
8. What must be installed on your system to decode a sound file?
A. The proper codec
B. Sound application software
D. Universal audio cables
9. Which of the following are valid audio file formats?
A. ASF, WMA, ASP
B. PCI, MP3, ASX
C. WAV, PCM, AU
D. MID, MPEG, AVI
10. Which term describes the stereo speakers in a 2.1 sound system?
D. Twins Answers
1. C. The bit depth refers to the number of characteristics of a particular sound
captured when sampling.
2. D. All recorded sound formats used in PCs today are derived from PCM format.
3. C. MIDI files contains no actual sound recording, but only a series of
commands stored in a text file for the sound card to interpret.
4. A. A Dolby Digital 5.1 setup has five speakers and one subwoofer.
5. A. Creative Labs developed the EAX presets.
6. D. The S/PDIF connector can replace analog connections on some sound cards.
7. D. The bigger the number, the better the quality, so 128 KHz is the king here.
8. A. You need a proper codec installed to decode a sound file.
9. C. WAV, PCM, and AU are audio file formats.
10. B. Stereo speakers are called satellites. ch20.indd 927 12/9/09 5:12:49 PM ...
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This note was uploaded on 04/27/2010 for the course COMPTIA 1201 taught by Professor N/a during the Spring '10 term at Galveston College.
- Spring '10