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Much of this material is adapted from the book QuickTime
for the Web: A Hands-On Guide, by Steven Gulie, originally
published by Morgan Kaufmann Publishers in April 2000. (The third edition
was published in June of 2003.)
What
is QuickTime?
- an enabling technology -- at the operating system level
-- that lets other applications (such as QuickTime Player,
Word, Excel, PowerPoint, FirstClass, and web browsers)
display multimedia
- a browser plug-in that can display audio,
video, animations, Flash files, music, and interactivity
- a very popular way to put sound and video on the web
or on CD-ROM
Multimedia is
- text, graphics, sound, and/or moving images brought together
in a meaningful way
- something which usually happens over time
QuickTime is, arguably, the best architecture for delivering multimedia
-- the oldest (first released in 1991); the most extensible; and one
which works equally well on Windows and Mac. (Its competitors include
RealPlayer, Flash, and Windows Media Player. Flash may currently be
more popular than QuickTime (the Flash video format,
FLV, is used by YouTube), but it is harder to download, harder to play
when downloaded, and, as of summer 20008, does not play on most portable
devices. The default controllers for Flash video provide limited functionality.
QuickTime Movies
QuickTime files are called QuickTime movies. A QuickTime
movie usually is a file with moving pictures and synchronized
sound -- but it also could be
- still images with synchronized text; or
- invisible background music; or
- karaoke; or
- many other things
A QuickTime movie is a file that tells a computer what kind
of media to present and when to present
it. The media could be -- audio, video, animation, still
images (BMP, GIF, JPEG, Photoshop, PNG, TIF), music (MIDI),
text, sprites, wired sprites, virtual reality panoramas or
objects.
A QuickTime movie has one or more tracks. Each track is
associated with media of a particular type. There can be
multiple tracks of the same type. Tracks can be synchronized,
sequential, side by side, superimposed, overlapping, or alternates
(based on the language of the operating system -- e.g., French,
Spanish, English, etc.) You create a QuickTime movie by adding
and arranging tracks.
The media in a QuickTime track can be contained in the movie
file itself, or they could be in one or more separate files.
For example, a track can point to the first and last parts
of a video so that only those parts are played -- but the
original video file is intact.
QuickTime media can be compressed in many ways -- and compressors
keep improving.
QuickTime can import to and export to other formats (e.g.,
.mp3, mp4, .wav)
QuickTime is frequently revised and improved
- Version 3.0 was released in the spring of '98, and is
totally cross-platform (i.e., same feature set on Macs
and Windows 95).
- Version 4.0 was released in June of '99, and added support
for streaming, Flash, and MP3.
- Version 5.01 was released in April 2001 and added support
for Flash 4, a new user interface, and AppleScript enhancements.
- Version 6 was released in July of 2002, and added support
for the MPEG-4 file format, MPEG-4 Video, and AAC Audio
- Version 7 was released in late April 2005, and added
support for the H.264 video codec, a.k.a. Advanced Video
Codec (AVC) or MPEG-4 Part 10
As of September 5, 2008, the current version of QuickTime
is 7.5
Delivery of QuickTime
There are three methods of delivering QuickTime movies.
- Local
Put the files either directly on users' hard disks, or on a CD-ROM,
or on a file server. This method allows you to use the highest bandwidth,
e.g., 1 MB/sec or more.
- Web server
This method allows users to view QuickTime files
from a web server.
QuickTime files on a web server can be viewed as they are downloading
to RAM. This feature is known as Fast Start. It allows QuickTime movies
to start playing within a few seconds -- long before the entire file
has downloaded
The bandwidth of this method is much
lower than through local delivery.
Unlike true streaming, described below, FastStart QuickTime files do
not allow random access to all parts of a file. For example, you can't
play the last few few minutes of a long clip until the entire clip
has downloaded.
- Streaming Server
A streaming server lets users watch files without any long downloads.
Streaming sends data continuously to a short buffer which is emptied
out as new data arrives. Streaming video or audio files begin after
only a very brief delay. Thus, a streaming server can send
out live transmissions (unlike a web server). Streaming files are
never stored locally -- not even in RAM. No copy is downloaded --
this can be good or bad. But -- streaming allows very large movies
to be viewed without using any of a user's disk space, and lets users
have true random access.
Disadvantages of streaming include:
- it does not retransmit lost data if there are glitches in the
network (or rather, when there are glitches :-)
- streaming video and audio must be highly compressed -- much
more than with FastStart
- certain media types can not be streamed -- such as sprite tracks
and Flash tracks
- users can't go backward in a file as quickly as with FastStart
movies
Putting QuickTime Movies in
Web Pages
You could just link to a QuickTime movie with <A HREF> tag
<A HREF = "demo.mov">Demo Movie</A>
The easiest way to embed movies in a web page is to use
the Apple-provided JavaScript uutility to generate the required
<EMBED> and <OBJECT> tags.
1. In <head> section of HTML, paste in
<script src="http://www.apple.com/library/quicktime/scripts/ac_quicktime.js" language="JavaScript" type="text/javascript"></script>
2. In <body> of HTML page, paste in
<script language="javascript">
QT_WriteOBJECT('moviename.mov' , '480', '376' , '', 'AUTOPLAY',
'False');
</script>
substituting the actual name of your QuickTime movie for
moviename.mov
Note that the '378' = the pixel height of the movie + 16
pixels for the QuickTime controller
QuickTime Pro version
Wellesley College has purchased a license for the Pro version
on all Macs and Windows in our computing labs. The $30 Pro
version, unlike the free version, allows one to save movies
from the web to a local hard disk; edit clips through
the Cut, Copy and Paste functions, merge separate audio
and video tracks, and Export movies. QuickTime 7 Pro includes
presets for Exporting to Web for an iPhone or a desktop computer.
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