In this discussion, we will define what multimedia is, the file types used, and the role of multimedia in WWW site development.
Contents:
Multimedia refers to the integration of video and sound into an information source. The idea is to enrich the information source beyond pure text and static graphics.
To enhance user's visits to your WWW set, you may want to include multimedia files in your HTML applications.
Multimedia files cover 2 main types of files:
Both of the preceding types of multi-media files fall into one of 2 categories:
To play mutli-media files from a browser, you need a player software. The default player for multi-media files in Windows is Window's Media player .
Windows has web-enabled its media player to update automatically over the WWW, allowing Microsoft to automatically update the software when you are logged onto the Internet with support for new mutli-media file formats.
Now, just why would Micorsoft want to be so helpful? Is it because they love you or because they want to control the player market? And why would they want to control the player market? Because a player is like a TV set and we all know what comes across a TV set - advertising! And what does advertising bring? Revenue! And let's not forget the advantage of being able to track your likes and dislikes in music in a sort of involuntary poll. What you listen to is of great importance to record companies.
Thankfully, the answer for the time being is YES! Real Audio is probably the biggest with MP3 readers gaining ground quickly.
The players are software add-ins to the browser, lending the browser capabilities it does not have. For example, Netscape can display HTML, JPG, GIF, and text files natively, but it can not display every available video and audio format. So, it does the next best thing... it provides the download pipe to feed the software add-in player the file it needs. The add-in player takes care of displaying the file.
These add-in programs are called plug-ins.
First, streaming file technology operates according to specific protocols/technologies like this that allow servers to stream data to the desktop.
Obviously, you need a server that uses streaming software. Streaming works differently than simply hyperlinking to a video or sound file.
With streaming, you hyperlink to a MIME file header with the <A> tag which communicates with the client-side viewer/player and points to a WWW server capable of streaming. The data stream (video and/or audio) is then transported to the client's desktop via HTTP and fed to the player.
Streaming is used to feed large files to a browser a piece at a time. Keep in mind that multimedia files are huge, often multi-megabytes in size.
When simply hyperlinking, you point to the multi-media file using the <A> tag. The file is downloaded to the user's PC and the player is kicked off to handle the file.
Because the need for video and audio clips is generally much more specific than that for simple clip-art, searching the WWW for free video and audio clips may not satisfy your needs.
Even so, there are sites out there with free clips. Use Dogpile to search for "free video clips", for example, to see several sites (be prepared for sex sites):
Free audio clip sites are numerous, too. Use Dogpile to search for "free audio clips" to see for yourself.
Of course, you may need to resort to creating your own multi-media files. For sound files, there are a number of file formats avaiable, the most popular of which is MP3 which we will discuss in detail later.
The question should be, how do I record sounds or video digitally? The answers range from simple to not-so-simple.
The simplest way to record audio (music, voice, etc) digitally is to use a microphone attached to a sound card and run Microsoft's Sound Recorder. Sound Recorder records in .WAV file which can then be uploaded to a site and with the appropriate <A> tag, delivered to the client's desktop.
You can also record directly into your sound card form an external stereo system (CD/Tape,vinyl) using a stereo Y-cable available from Radio Shack to go from the AUX out jack of the stereo into the "line in" port of the sound card. Again, you can use Sound Recorder to grab the incoming audio signal.
With CD players attached to your PC, you can record directly from the CD.
The big dollar solution calls for specialized sound cards with multiple input jacks with special, multi-channel recording software. Many music recording projects are now being done on home PC recording studios that can cost as little as $400 up to $1,500 and beyond.
In the old days (just a couple of years ago), you needed a specialized frame grabber video card to hook up analog (tape) video cameras and record the playback onto your computer.
Nowadays, video cameras that can record digitally cost less than $1,000. Even the analog cameras have special output ports to hook into new video cards on PC's for recording from playback. Heck, digital still photography cameras can be had for less than $100.
Check here for purchase ideas.
MP3 was developed by a group of German scientisits in the late 80's and is a verison of the original MPEG format for delivering high quality audio over Internet connections.
MP3 has just recently risen in popularity as the bandwidth of Internet connections has increased to the point where delivery of near-CD to CD quality audio to the desktop is now possible.
The MP3 site attests to the popularity of MP3 format music.
Beyond the fact that MP3 allows transmission of high quality audio over typical internet links, MP3 has opened the doors to self-publishing just as HTML did in the early 90's.
With MP3, songwriters can publish their own music at little to no cost other than PC recording equipment. No longer do bands have to wait on a recording contract from a music publisher like Sony. No longer do bands have to rely on the distribution channels of companies like Capitol Records. Now with MP3, bands can record and publish CD quality music for distribution over the WWW.
In fact, there are hand-held devices that act as radios by downloading and playing MP3 files. Several sites have been dedicated to providing free web space to musicians, categorizing their music for easy selection by 'net surfers.
Third worlders use MP3 as the primary distribution source for "World" music. In the US, MP3 is just catching on and is growing by leaps and bounds.
As far as I can tell, companies that provide software to play, record, convert, or serve up MP3 format files must pay royalties to the patent holders of the MP3 specification. These software players run advertisements on their WWW sites during playback of the MP3 files and/or charge for use of their software.
In the same way as HTML has allowed all of us to be published writers on the WWW, MP3 allows anyone to publish audio (music, spoken word, etc) on the WWW.
(pg. 160) Internet Explorer supports the <bgsound> tag that plays an audio file while the HTML document downloads to the user's PC. Keep in mind that the tag is proprietary and works onlyfor MS-IE. In fact this page uses the background sound tag, though you won't hear it unless you have a sound card and speakers and are using MS-IE V4.0 or higher.
To play an audio file in the background, use the SRC attribute of the BGSOUND tag as shown in the BODY of your HTML:
You can use the LOOP attribute to really drive visitors crazy by playing the sound file over and over and over...
The EMBED tag is Netscape's equivalent of MS-IE's BGSOUND tag.
To play an audio file in the background, use the SRC attribute of the EMBED tag as shown in the BODY of your HTML:
In Chapter 13, pg 432, the book discusses the OBJECT tag for embedded content. The object tag was created under HTML 4.0 to allow, amongst other things, background sounds across browsers. To play a sound file (or any other playable file), code the following in the BODY section of your HTML document:
The browser loads the appropriate player software (plug-in) and feeds the file that you specified in the DATA= attribute to the player. Curiously, Netscape actually embeds the sound player in the browser window, while MS-IE simply spwans off a new window for the player. Go figure...
The code for the marquee tag is simple:
There are a few attributes for the MARQUEE tag to allow you to control the direction of the scrolling, align the scrolling text with surrounding text, and start/stop scrolling text, change its size and color, etc. I'll leave those attributes to you to read about on pages 163..166.
The anchor tag can link to a sound file instead of another HTML file:
Linking to a video, sound, or graphics file using the ANCHOR tag is called Referenced Content (as opposed to embedded content like the OBJECT tag affords).
Since you now know that different file types require special players, don't assume that all users have installed the plug-ins needed to play your multimedia files. If you provide links to multimedia files, you should tell the user what format the file is in or what player they need as well as the size of the file if it is especially large, say, over 200K.
Many sites that offer multimedia files also have links to WWW sites where users can download the players needed to view the files.
For the most part, viewers like RealAudio and Microsoft's Media Player contain support for most popular file formats. Unfortunately, not all users have the latest and greatest versions of the players and some do have no players at all.