Sams Teach Yourself Web Publishing with HTML and CSS in One Hour a Day (5th Edition) P45 pdf
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Embedding Sound and Video
<img src="a01607av.gif" dynsrc="a01607av.avi" loop="2" start="fileopen" />
Internet Explorer will ignore the value of the src attribute as long as the video supplied by dynsrc is
valid.
Task: Exercise 11.2. Embedding a QuickTime Movie
For your second exercise, you'll try your hand at embedding a QuickTime movie in a web
page. QuickTime is a video format created by Apple. Apple recommends that you use the
combination of the
<object> and <embed> tags that I've discussed in this lesson.
For starters, create or open a web page template similar to the following:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
" /><html>
<head>
<title></title>
</head>
<body>
</body>
</html>
From here, title the page and add a <div> element that you will use to center everything on
the page.
Next, add a heading that appropriately describes the video and a title for the video:
<div align="center">
<h1>Apollo 17 Videos</h1>
<p>Astronauts placing the flag on the Moon</p>
</div>
Now it's time to add the video itself. Start with the <object> tag. Here's the code:
<object classid="clsid:02BF25D5-8C17-4B23-BC80-D3488ABDDC6B"
codebase=" />height="136" width="160">
<param name="src" value="Apollo_17_Flag.mov" />
<param name="autoplay" value="true" />
<param name="controller" value="true" />
<embed src="Apollo_17_Flag.mov" height="136" width="160"
type="video/quicktime"
pluginspage=" />
</object>
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Embedding Sound and Video
You should recognize this code from what you've seen previously in this lesson. The
classid and codebase for QuickTime are unique to that plug-in, as is the plug-ins page
specified in the
<embed> tag. You should also note that I set the height of the movie to 136.
The movie is actually 120 pixels high, but the QuickTime player includes controls that are
16 pixels tall, so I added 16 pixels to the height of my movie. If I hadn't done so the
controls would be cut off.
I used two parameters that are specific to QuickTime
autoplay and controller. I set the
autoplay parameter to true so that the movie would start playing as soon as the page is
displayed, and I set
controller to true so that the video controls would be shown (this is
the default). Had I set
controller to false, the controls would not appear and I could have
set the
height attributes to 120. To see whether this works, test the page using your web
browser. When you're satisfied, add a final piece to the page that will show people where to
get the QuickTime plug-in if they need it. Because this is the last element on the page,
remember to close the
<div> with the end tag.
<p>Apple <a href=" is
required to view this movie.
<a href=" /> <img src="qt7badge_getQTfreeDownload.gif"
border="0" align="absmiddle" width="88" height="31" /></a></p>
When it's all put together, the source code for your web page (shown in Figure 11.10)
should look like this:
Input
<html xmlns=" /><head>
<title>Apollo Multimedia Archive</title>
</head>
<body>
<div align="center">
<h1>Apollo 17 Videos</h1>
<p>Astronauts placing the flag on the Moon</p>
<object classid="clsid:02BF25D5-8C17-4B23-BC80-D3488ABDDC6B"
codebase=" />height="136" width="160">
<param name="src" value="Apollo_17_Flag.mov" />
<param name="autoplay" value="true" />
<param name="controller" value="true" />
<embed src="Apollo_17_Flag.mov" height="136" width="160"
type="video/quicktime"
pluginspage=" />
</object>
<p>Apple <a href=" is
required to view this movie.
<a href=" /> <img src=" qt7badge_getQTfreeDownload.gif"
border="0" align="absmiddle" width="88" height="31" /></a></p>
</div>
</body>
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Embedding Sound and Video
</html>
Output
Figure 11.10. Embedded QuickTime movies use special attributes
created by Apple.
[View full size image]
Table 11.7 summarizes the attributes that QuickTime supports.
Table 11.7. Attributes/Parameters Supported by QuickTime
Attribute Description
autohref
Can be set to true or false (default false). Starts loading the
URL specified in the
href attribute immediately if true.
autoplay
When TRue, plays the movie when the plug-in estimates the clip
can be played without waiting for more data (
true or false).
bgcolor
Specifies the background color of any space not taken up by the
movie. QuickTime 6 accepts colors specified using hexadecimal
notation or a color name.
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Embedding Sound and Video
cache
When true, the browser caches movies, resulting in the browser
replaying a movie from its cache rather than downloading again.
Supported by Netscape Navigator 3 and later only (
TRue or false).
controller
When TRue, makes the movie controller visible. Sixteen pixels
should be added to the height of the movie when the controller is
shown and the
height attribute is used (true or false).
correction
Applicable to QuickTime VR only (none or full).
dontflattenwhensaving
Saves the movie without flattening (no value).
enablejavascript
If this is set to true, you'll be able to control the QuickTime
plugin using JavaScript on the page.
endtime
Defines the last frame of the movie (time in hours:minutes:
_seconds:frames).
fov
The initial field-of-view angle for QuickTime VR movies (integer
between 8 and 64).
goto
Same as qtnext.
height
Required. Defines the height of the region in which to display the
movie. If the movie controller is visible, add 16 to the movie
height to reach the total height required (in pixels).
hidden
Hides the movie, and really is only useful for background sound
(no value).
hotspotn
Enables hotspots in a VR panorama where n is the hotspot ID
(URL).
href
Links to another web page or movie (URL). (See the target
attribute.)
kioskmode
When true, no pop-up menu is available for the movie and you
cannot save it by dragging and dropping it (
true or false).
loop
When TRue, the movie plays in an infinite loop. When set to
palindrome, the movie will play alternately forward and backward
(
true, false, or palindrome).
movieid
A numeric ID (integer).
moviename
The movie name (text).
node
Sets the initial node for multinode QuickTime VR movies
(integer).
pan
Sets the initial pan angle for QuickTime VR movies (integer from
0 to 360 degrees).
playeveryframe
When set to true, audio tracks are turned off and every frame of
the movie is required to play, even if that forces a slower frame
rate (
TRue or false).
pluginspage
The URL to the QuickTime download page. You should set this to
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Embedding Sound and Video
qtnextn
Identifies the URL for a movie to load and play when the current
movie finishes. The number
n can be an integer from 1 to 255
and defines the index of the URL in the playlist. The number
n is
the index of the next
qtnext URL to load (URL or goton).
qtsrc
Forces a web browser to use the QuickTime plug-in. The URL
overrides any value in the
src attribute (URL).
qtsrcchokespeed
Specifies the data rate of a movie, regardless of the actual
connection speed (number).
qtsrcdontusebrowser
Instructs the plug-in to load the movie using its own internal
methods rather than using the browser, thus preventing caching.
scale
tofit
scales the movie to the dimensions set by the height and
width attributes. aspect scales it to fit this box while maintaining
the original aspect ratio of the movie. A number scales the movie
by that ratio (
tofit, aspect, or a number).
src
Sets the URL of the movie (URL).
starttime
Sets the first frame of the movie (time in hours:minutes:_
seconds:frames).
target
If set to quicktimeplayer, launches the QuickTime Player to play
the movie specified in the
HRef attribute. If set to myself, plays
the movie specified in the
HRef attribute in the player embedded
in the page.
targetn
Used with hotspot and HRef. Sets the target for links that use the
hotspot or href attribute. The number n corresponds to the
hotspot number (name of a valid HTML frame).
targetcache
Caches the movie that is targeted by another movie (TRue or
false).
tilt
Sets the initial tilt angle for QuickTime VR movies (integer).
type
Defines the MIME type of the movie. If the movie is visible and
has
width and height values, type must be included. This
attribute is supported by Netscape Navigator 2 or later only
(MIME type).
volume
Sets the initial audio volume. The default is 100 (integer from 0
to 100).
urlsubstitute
Accepts two strings separated by a colon. In all URLs specified in
the
HRef attribute, or sprite or hotspot URLs, it replaces the first
string with the second. So,
"foo:bar" would replace any instance
of
foo in a URL with bar.
width
Sets the width of the display area for the movie (in pixels).
Note
QuickTime VR enables the author to create movies with a 360-degree view of
an object that the user can pan through using the QuickTime viewer.
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Embedding Sound and Video
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Sound and Video File Types
Sound and Video File Types
I challenge anyone to come up with a complete list of the audio and video formats currently in use
today! There are so many that it's not productive to survey all of the different multimedia file types,
their extensions, and MIME types. So, I'll just cover the most popular ones, or at least the ones you
might be inclined to include in your web pages.
Before I list them, however, it would be useful for you to understand what factors to consider when
choosing a multimedia format. By this, I mean sound or video quality, the size of the final file, how
many plug-ins or players are compatible with the format, and how readily available the file format is.
The quality of sound and video files depends primarily on the original sampling rate, number of bits used
per sample, and the number of channels.
The sampling rate is the number of times per second the sound or video is sampled or measured. This
value is represented in thousands of cycles per second or kilohertz (KHz). Imagine yourself walking
through a room and being able to open your eyes only once every five seconds. Do you see how that
might be dangerous? Now imagine yourself opening and closing your eyes every second. You get a
much better picture of what is around you and a closer approximation of reality. It's the same with
sampling rates: The faster the sample, the closer the sound or video will represent the original
recording. The only problem with this is that when you increase the number of times you sample per
second, the amount of data quickly becomes voluminous.
The number of bits you use determines the fidelity of the sound. An 8-bit sample, for example, can
measure 256 discrete values, whereas 16-bit samples measure more than 65,000 values. The more bits
you use, the closer you come to the actual pitch of a sound or the color in a video clip.
The number of channels refers primarily to audio files, where you can have mono (one channel)
recordings, stereo (two channel), and even more. Having more channels enriches the sound and makes
for a more enjoyable experience, but again, at the price of file size.
Six audio file types are in common use on the Web today, each with its own unique advantages and
drawbacks.
● Musical Instrument Digital Interface (MIDI) files are synthesized rather than recorded sound. The
file sizes are small; however, because you can't play back recorded sound, MIDI plays a niche
role. (In fact, MIDI files can be so grating to listen to that you should probably never use them in
a web page at all.)
● MP3 audio offers four types (or layers) of sound files and is very popular because of MPEG's
widespread acceptance as an audio and video format. MP3 audio is by far the most popular and
common format for MPEG audio because it can compress audio files very efficiently. MP3 remains
the more popular format, and is supported by devices ranging from portable audio players like
the iPod, to DVD players, to car stereos. MP3 files can also be streamed, which means that they
can be played as they're being downloaded, and sites can provide a constant stream of MP3-
encoded audio to act as an Internet radio station.
● Waveform (WAV) files originally were created by Microsoft and IBM, but can be played by nearly
any audio program. WAV files are popular for small sound clips. Larger files are generally stored
in MP3 or another format.
● Windows Media Audio (WMA) files are supported by Microsoft's Windows Media Player and
anyone who licenses the formats. WMA is a format that's designed to compete with MP3, and
offers both quality and compression better than MP3. There are actually a number of different
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Sound and Video File Types
formats that live under the WMA banner, including a straight MP3 competitor, a lossless audio
format for distributing music purchases, and a compression scheme that's designed for speech
rather than music. WMA files can be protected using a DRM scheme created by Microsoft that
prevents the files from being shared freely.
● AAC audio files are compressed using the Advanced Audio Coding format. AAC is another MP3
competitor, and is the default audio format for Apple's iTunes music player. Audio tracks
purchased through the iTunes Music Store are encoded using AAC, and are protected by a DRM
scheme that prevents them from being shared freely. AAC is the encoding format behind the
MPEG 4 audio format.
● RealAudio is an audio format designed for streaming. It's generally associated with Real
Networks's line of media players. Unlike the other formats listed here, it sacrifices quality for
compression so that even users with low bandwidth can receive live audio feeds over the
Internet.
Table 11.8 summarizes the popular audio formats.
Table 11.8. Common Audio File Formats
Name Extension(s) MIME Type
MIDI
MID, RMI
audio/mid
Waveform (WAV)
WAV audio/wav
MPEG Audio MP2, MP3
audio/x-mpeg
RealAudio RA, RAM
audio/vnd.rn-realaudio
Windows Media
WAM audio/x-ms-wma
AAC M4,
AAC audio/aac
The common video types available are AVI, MPEG, and QuickTime, and are described in the following list:
● AVI, which stands for audio/video interleaved, is a very popular Microsoft Windows video format.
It's very widely supported. AVI files can be encoded using any one of a number of formats, so
users must not only have an AVI player on their computer, but they must also have the codec
necessary to view a file installed a well.
● MPEG video is used by things such as satellite television and digital cable. It's also a popular
format for distributing video over the Internet.
● QuickTime video is proprietary to Apple. However, there are QuickTime players available for both
the Mac OS X and Windows.
● Windows Media Video is the counterpart to Windows Media Audio. There are two Windows Media
Video schemes. The first is a format designed for streaming and distributing video over the
Internet; the second is a professional format designed for storing high-quality video for
broadcast or archival.
● RealVideo is a format designed for high compression and streaming to Real Networks's media
players.
● Flash Video is video that's embedded in Flash movies. The advantage of this approach is that the
only dependency is the Flash player, which is already included with most browsers. The controls
for video playback are also built into the Flash movie, so there's less confusion when it comes to
figuring out what sizes to use when embedding the movie in a web page.
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Sound and Video File Types
Table 11.9 summarizes these video formats.
Table 11.9. Common Video File Formats
Name Extension(s) MIME Type
Audio/Video Interleaved
AVI video/x-msvideo
MPEG MPEG, MPG
video/mpeg
QuickTime MOV, QT
video/quicktime
Windows Media
WMV video/x-ms-wmv
RealVideo
RV video/vnd.m-realvideo
Flash Video
SWF application/x-shockwave-flash
Another factor you might want to consider is whether a particular file type is streamable. This means it
can be played as it's being downloaded. At one time, RealAudio and RealVideo were the two main
streamable audio and video formats. These days, though, there are players for many file types that
allow the files to be streamed. For example, many MP3 players allow MP3s to be played as they're
downloaded, and QuickTime files are also streamed to the player. When you're choosing a multimedia
format, you should strongly consider one that supports streaming.
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Of Plug-Ins and Players
Of Plug-Ins and Players
Plug-ins are external programs that can be launched within your browser. They enable you to add
capabilities to your browser without adding new functionality to the browser software itself. Plug-ins are
often installed as part of a larger standalone application. For example, the QuickTime Player is a
standalone application used to play videos, listen to audio files, and view images, but it also installs plug-
ins that enable you to view QuickTime files in your browser. On the other hand, Macromedia's Flash
Player exists only as a browser plug-in. It simply enables you to view Flash animations within web pages.
Plug-ins originated with Netscape 2.0. Internet Explorer uses ActiveX controls, which provide similar
functionality, but work differently. The advantage of the Internet Explorer approach is that new ActiveX
controls can be downloaded and installed without closing the browser when you encounter a file that
requires a control in order to be viewed. I'm lumping all of these under the general-purpose label of
plug-ins, but the approach differs between the two browsers. Mozilla Firefox uses plug-ins just like its
ancestor, Netscape Navigator.
As you learned earlier today, the problem with multimedia files that require plug-ins is that if you use
them in your web pages, your visitors must have the correct plug-in installed in order to view them.
Visitors who don't have your plug-in will get empty space or broken icons on your page where the
multimedia should be or, in the case of Internet Explorer, be prompted to install the appropriate control.
To further complicate the matter, some plug-ins are available only for some platforms.
The big four plug-ins are Windows Media Player, which is bundled with the latest versions of Windows;
QuickTime, which is native to Macintosh but is available for Windows as well; RealPlayer, which is also
available for Windows and Mac OS, and Flash Player, which is installed with Microsoft Internet Explorer.
They each support their own proprietary formats, which generally only they can play, and except for
Flash, they can also all play the common audio and video formats. When you have more than one of
these applications installed, they sometimes fight over which of them gets to play the types of files that
they have in common.
Windows Media Player
The Windows Media Player, available at www.microsoft.com/windows/mediaplayer, is included as part of
the Windows operating system and can play many multimedia file types. It also offers a number of other
features, such as the capability to copy songs from CDs, burn them to CDs, and maintain a media
library. Version 10, shown in
Figure 11.11, is currently available, but only for users of Windows XP.
Users of Windows 2000, Windows Me, Windows 98 SE, and Mac OS X can use version 9. Windows 98
users can install version 7.1. If you're using Windows NT 4.0 or Windows 95, you must stick with
Windows Media Player 6.4.
Figure 11.11. The Windows Media Player can play MP3s and other popular
multimedia formats.
[View full size image]
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