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How to Use Multimedia
Multimedia for the Web refers to the process of delivering files that contain information that is not necessarily text. These files could contain audio, video, Flash, VR, etc. The following pages describe how to use various types of multimedia within a web page.
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Streaming refers to a process of sending a movie file from a special streaming server across a network and displaying it in real time without waiting to download a copy of the file first.
A typical web server delivers files to a user's browser which, after the download, will then interpret and display them. By using a streaming server, large multimedia files are delivered in real time without the need to download the entire file first, the browser will display (or play) the stream as it comes in. Not having to wait for the download to complete is an obvious advantage to the user as the alternative to streaming is waiting for the multimedia file to download before being able to view it &emdash; QuickTime offers a third choice as a combination of these methods in the form of a Fast Start movie that can be delivered from a standard web server.
When do you need to use streaming?You should stream if you are sending realtime (live) broadcasts (audio or video) over the Internet. If not then you should consider the following before streaming a multimedia file:
Streaming Pros
- Can send live (real time) sources such as TV or radio
- Can be used for broadcast and multicast (sending one stream to many viewers)
- Provides random access to long movies
- Uses no space on the viewer's hard disk
- Never uses more bandwidth that it needs
- Can stream individual tracks into a movie from anywhere
- Doesn't give the viewer a copy of the movie file
Streaming Cons
- The movie breaks up if the movie data rate exceeds the connection speed
- Always loses some packets over the Internet
- Currently limited to audio, video, MIDI, and text; other media types, such as Flash, don't stream
- Doesn't always go through firewalls
- Requires a streaming server and/or a broadcaster
QuickTime allows you to integrate recorded sound, MIDI, text, still images, motion video, virtual reality, live streams, games, and user interactivity in a single Web-friendly cross-platform package (or movie) that plays just about every kind of multimedia there is.
Although you can create QuickTime movies with several different programs, QuickTime Pro is one of the best choices for putting together the final version since it allows you to merge many different source files into a complete movie while taking advantage of all the QuickTime features.
For more information check out the Apple QuickTime web site or better yet, get the book:
Apple Computer, Inc., QuickTime for the Web, Second Printing August 2000
Academic Press 525 B Street, Suite 1900, San Diego, California 92101-4495, USA
http://www.academicpress.com
QuickTime offers a method of delivering a multimedia file from a standard web server in the form of a Fast Start movie. The complete file is downloaded to the user's hard disk but, unlike a standard file, the QuickTime plug-in will begin playing the movie as soon as enough data has been received to keep the download ahead of the player, thus the user sees the movie similar to a stream.
You consider the following before using a QuickTime Fast Start movie:
Fast Start Pros
- The movie gets through no matter how slow the connection (this does not imply that the user's computer will be capable of displaying the movie)
- Lost or damaged packets are retransmitted until they get through
- No problem with firewalls
- Movie plays as it downloads if the connection is fast enough
- Can use all QuickTime media, including sprites, Flash, and VR
- No special server software needed
Fast Start Cons
- Can't broadcast or multicast
- Can't send live (real time) transmissions
- Can't skip ahead: the user must download the whole movie
- Puts a copy of the movie file on the user's disk
- Can use all available bandwidth (see QTCHOKESPEED)
QuickTime offers a verity of recording formats to choose from. The exact one to use will be dependent on may variables, i.e. processor speed, user's network connection speed (modem, DSL, Ethernet), type of presentation (web, CD, DV, etc.). The following are recommended starting settings for each format:
Web:
- Video: Sorenson @ 15 kbytes/sec, one key frame every 10 seconds.
Audio: IMA 4:1
- Audio Only: Qualcomm for narration, QDesign @ 40 Kbps for 56k connections, 100Kbps for faster connections for music.
DVD:
- Video: MPEG-2
- Audio: AC-3
To export QuickTime media for playback over the Internet using QuickTime Player:
- Choose Export from the File menu and choose a format
to export to
- Click Options, then check "Prepare for Internet
Streaming"
- Choose the appropriate option from the pop-up
menu
- Choose an appropriate recording method
Fast-Start Movie. This is a good choice for movies available through hypertext transfer protocol (HTTP). It's adequate for movies that have a hint track.
Fast-Start Movie - Compressed Header. This is a better choice for movies available through HTTP, but don't choose this if the movie has a hint track. (The streaming server cannot read a compressed header.)
Hinted Streaming Movie. Choose this option if you are putting the exported file on a streaming server. The file will not stream without a hint track for each track in the movie.
The simplest and most effective way to include a QuickTime movie on your web page is to create a box with a controller by using the <EMBED > tag as follows:
<EMBED SRC="MyMovie.mov" WIDTH="310" HEIGHT="240">
SCR specifies the name of the file to load, which can also be a URL.
WIDTH and HEIGHT tell the browser how much space to give the plug-in.
NOTE: Add 16 to the height of the movie to make room for the controller. For a sound-only movie set the height to 16 and the width to anything that looks good.
Never set the height to less than 2, even if the movie is hidden, because some browsers will die a horrible death.
If you want to be a little nicer to those uses that don't have the QuickTime plug-in yet, send them to the QuickTime download site by use the following:
<EMBED SRC="MyMovie.mov" WIDTH="310" HEIGHT="240" PLUGINSPAGE="http://www.apple.com/quicktime/download/">
Description:
If "True", the plug-in is not displayed. This can be used to setup a background sound, although other parameters including AUTOPLAY and CONTROLLER will need to be set as in the example below.
Syntax:
To hide the plug-in and play a background sound:
<EMBED SRC="BkSound.mov" WIDTH="2" HEIGHT="2" HIDDEN="True" CONTROLLER="False" AUTOPLAY="True">
Description:
If "True", the plug-in starts playing the movie without user intervention.
Syntax:
<EMBED SRC="MyMovie.mov" WIDTH="360" HEIGHT="240" AUTOPLAY="True">
Description:
If "False", the plug-in does not display a controller bar at the bottom of the plug-in window. This can be a bad thing because without the controller the user can't stop or rewind the move and if you haven't set AUTOPLAY ="True" then they can't even start the movie.
Syntax:
To hide the plug-in and play a background sound:
<EMBED SRC="BkSound.mov" WIDTH="2" HEIGHT="2" HIDDEN="True" CONTROLLER="False" AUTOPLAY="True">
Description:
Choke speed limits the load on the server and prevents a user with a high speed connection from tying up all the available bandwidth. You do this by passing the browser a small dummy QuickTime file in the SRC parameter and the actual movie with the choke speed in the QTSRC parameter. Try setting the choke speed about 15% higher then the movie's data rate. By setting QTSRCCHOKESPEED="movierate" QuickTime will try to limit the bandwidth to only what is needed.
Syntax:
<EMBED QTSRC="MyMovie.mov" SRC="Dummy.qti" QTSRCCHOKESPEED=56000">
Description:
The volume can be set as a percentage from 0-300 of the volume set on the users computer. The default volume is 100 which corresponds to 100% of the users volume. It is best to set the volume to 75 for MIDI sounds.
Syntax:
<EMBED SRC="MyMIDI.mov" WIDTH="120" HEIGHT="16" VOLUME="75">
Beware for Windows IE 5.5 SP2 and 6.0+
Microsoft Internet Explorer for Windows, versions 5.5 SP2 and 6.0 no longer support Netscape-style plug-ins, such as the plug-in installed as part of QuickTime 5.0.2 and earlier. Consequently, Windows customers using these versions of Explorer who visit your site may be unable to view QuickTime content in their browser. You should add the following HTML OBJECT element with an enclosed EMBED element to make the new ActiveX control for QuickTime available.
<OBJECT
CLASSID="clsid:02BF25D5-8C17-4B23-BC80-D3488ABDDC6B"
WIDTH="160" HEIGHT="144"
CODEBASE="http://www.apple.com/qtactivex/qtplugin.cab">
<PARAM name="SRC" VALUE="MyMovie.mov">
<PARAM name="AUTOPLAY" VALUE="true">
<PARAM name="CONTROLLER" VALUE="false">
<EMBED SRC="MyMovie.mov" WIDTH="160" HEIGHT="144"
AUTOPLAY="true" CONTROLLER="false"
PLUGINSPAGE="http://www.apple.com/quicktime/download/">
</EMBED>
</OBJECT>
CLASSID must always equal:
clsid:02BF25D5-8C17-4B23-BC80-D3488ABDDC6B
CODEBASE must always equal:
http://www.apple.com/qtactivex/qtplugin.cab
PLUGINSPAGE must always equal
http://www.apple.com/quicktime/download/
The OBJECT element is used by Internet Explorer on Windows 9x/NT/2000/XP platforms and by other browsers that support the QuickTime ActiveX control. The enclosed EMBED element is used by Netscape browsers, Internet Explorer for the Mac, and other browsers that support the "Netscape style" QuickTime plug-in. Browsers that understand the OBJECT element ignore the EMBED element; those that don't understand the OBJECT element use the EMBED element.
For more information see Apple's QuickTime web sit at http://developer.apple.com/quicktime/compatibility.html
To be sure that the QuickTime plug-in is always used to display your movies, include the following code:
<EMBED QTSRC="MyMovie.mov" HEIGHT="310" WIDTH="240" SRC="UNeedQT4.pntg" TYPE="image/x-macpaint" PLUGINSPAGE="http://www.apple.com/quicktime/download/">
This has the affect of forcing the user's browser to use the QuickTime plug-in. If the user doesn't have QT installed then they will be directed to the Apple QuickTime web site to get if for free. If they don't have the current version of the plug-in they will see the UNeedQT4.pntg MacPaint image directing them to the Apple site to upgrade. If all is OK, then they will be presented MyMovie.mov.
