Manfred Kuechler (Hunter College)
Version 1.8.3 (February 22, 2000) -- version history

Multimedia contents for course web pages: 
Preliminary Explorations

Introduction

• like Powerpoint (which comes as part of the MS Office 97 package which is available via the CUNY bulk purchase agreement for $40 or less) for multi-media production and
• like Netscape Composer or the html support built into recent versions of WordPerfect and MS Word as well as -- at Hunter -- a convenient course management system like ERes.

Streaming technology is still in its early stages, but no longer in its infancy. Though there are different products and approaches, the RealSystem emerged as an industry leader eclipsing early competitors like VDOlive. However, both MS (Windos Media Player) and Apple(especially with the "preview" release of Quicktime 4 in April 1999) also offer their own streaming solutions. One of the largest web sites using streaming video (CNN) offers all clips in two versions, for the RealPlayer and for the Windows Media Player.

In 1998, Real Systems launched its G2 series (I trust G2 stands for 'second generation') and a multitude of products have become available -- some for free, some for modest cost, some for real money. This page documents my start into exploring these (low cost) products for their potential of generating multi-media contents for college courses and distributing it over the web (via course web pages).

Call for exchange of ideas and experiences. This is a start. While I have used web course pages since fall 1995, my experience with multimedia contents/presentations is still limited. So, most examples of multimedia contents you see on this page are rather crude, quickly put together to test the interplay with web distribution. As other colleagues are beginning to take in interest in these issues I am getting better material to experiment with, and I invite such collaboration.

Real Products Overview. I am not going into any details here, check their web site if you want more detail. However, it is important to realize that these products fall into three categories and to understand the relevance of each category for the purpose discussed here:

• Production tools -- software that helps you (the faculty member) to produce multimedia (audio, video) contents on your work station and -- to a lesser degree -- to move it to a remote computer (server box)
• Server tools -- special software that works in conjunction with or in place of a regular web (httpd) server, which may or may not reside on the same remote computer (server box); only system administrators would deal with (install, maintain)  such software. A special RealServer is not necessary for small scale explorations, but it is necessary for optimal performance and it is certainly necessary for regular course use.
• Player tools -- software that works with a regular web browser (e.g., Netscape)  and enables the user (student) to view the specially formatted files generated by the production tools. A very recent addition (still in beta release as of May 1999) is the Real Jukebox (comes as part of RealPlayer Plus) which is actually part production and part player tool. As a production tool, it allows you to "rip" off contents from any regular audio CD (which you can play in your computer CD drive) and convert it into audio file including the high quality mp3 standard.

A number of production tools are also available for free, more elaborate versions as well as related products sell at reasonable prices (like RealProducer Plus at $150) or for real money (like RealProducer Pro for $500) . Another useful tool is the Real Presenter  (about $40) which allows to convert a Powerpoint presentation into Real format; but it is useful for Powerpoint presentation with audio only and any animations are not preserved (details).

As to servers, Real contents can be served by a regular web server (only minor adjustments in terms of specifying additional "mime types" -- a five minute job for the system administrator -- are needed). All demonstrations in this page are served from both a standard web server (Apache 2.5 running under Linux kernel 2.0.32 on an i686; in October 1999 upgraded to Apache 3.1.6 running under Linux kernel 2.2. [Redhat Linux 6]) and -- initially -- from the free basic server from Real Systems. In March 1999, the Real Basic Server G2 Plus (which then sold for $695) was installed and the links on this page were changed accordingly. The
Real Basic Server was upgraded to version 6.1 (beta 2) on October 22, 1999.

With modem connections you are likely to see better connections via the RealServer. I will keep the comparison with the regular server, because setting up the RealServer requires the cooperation of the system administrator. While refusing to add a few mime types would be sheer obstruction, some system administrators may be balking at the suggestion to install the RealServer. Unfortunately, not all computer support professionals are so helpful like Andrew Blaner, David Gallagher, or Bill Gruber -- to name just a few outstanding people I have had the pleasure to work with. So, settling for a regular web server is a workaround for faculty at locations with an obstinate computer support unit.

Final note: The G2 player and production tools are available for Win9x platforms as well as for Unix and Mac (final release of the latter in spring 1999).

Sample Contents

Example 1:

• The audio was taken straight from a regular music CD (played in my computer's CD drive) using the RealProducer, a very simple and straightforward job. The file size is 276 KB. The link will bring up a web page with an embedded RealPlayer. Just click on the controls in the player image to start, stop, control volume, etc. If you like the recording, here is more information on the artists (scroll down on that page to get to the English version).

Example 2:

• The four photos used were taken by myself with a cheap camera that I have had for years -- nothing fancy, nothing digital. To save time, I simply used the digital versions that Seattle Filmworks provides for an extra $4 per roll of film developed and printed. Alternatively, I could have scanned prints of the photos, and my Agfa SnapScan EZ scanner (bought for under $100) does a great job with color photos. But since not everyone has a scanner, I tried to be as bare bone as possible. Note that scanning will give you better digital images than using a digital camera -- unless you use high-priced professional equipment.
• The photos were converted from Seattle Filmworks' own format into .bmp (increasing file size by about factor 10 to over 1 MB for each 4x6 photo), then edited with Corel Photoshop (part of the Corel WP suite) to reduce the size to 4" width and resaved in .jpg format. Changing the size of digital photos is best be avoided altogether, but if it has to be done, it should be done while the image is a non-compressed format like .bmp.
• The 2.6x4 photos in .jpg format were only about 20 KB each. But "bandwidth" is valuable, so I used a special jpeg compression program to reduce the size even further. I used an old version (1.2), the current version (2.02) probably does an even better job. Note that every photo editing program gives you some options as to quality level (and hence file size) when saving an image as jpg, but this special program achieves a much better compromise between file size and quality. The final images are all less than 5 KB in size.
• The RealPix users guide suggests to use their own jpegtran program (comes with the free stuff) for a final stage of prepping the photos. This does not affect the file size, but optimizes the delivery of the image from the web server to the browser. It did this for one of the photos, but not for the others and could not tell a difference. But a difference may show under adverse (heavy traffic with delays) delivery conditions.
• Starting with a set of regular images (in .jpg format), a RealPix file is written in which the use (display and movement along a timeline) of the still photos is defined. I simply used one of the sample files (RealPix HTML\media\viewchng.rp) that comes with the free stuff and replaced the still photos in the sample file with my own images. The .rp file consists of a number of tags -- very similar to html tags. So, it takes a bit of time to learn these tags and produce the desired effects. The free stuff does not include a convenient specialized editor. Writing such a file feels like writing an html file in the "early days". You can check whether your .rp file does what you want it to do by opening it locally (on your work station) in the RealPlayer G2.
• If you have a RealServer available, you would simply upload the .rp file to a subdirectory on the server box (exactly the same way as you handle an ordinary html file). If you want to use a regular web server, you have to go through a few more steps. First, you need to set up a .smil (pronounced "smile") file -- which you will need for any truly multimedia presentation anyhow. I discuss these smil files in the next example. Then, you write a straight text file with a single line which describes the location of the smil file like:

http://maxweber.hunter.cuny.edu/~mkuechle/alaska-mute.smil
and save this file with the extension ".ram". This .ram file is put on the (regular web) server together with .smil, the .rp, and .jpg files for the basic images (photos). The link on the referring page (like this one) points to the .ram file. Provided that the mime types have been properly defined on your regular web server, clicking on a link pointing to the .ram file, makes the web server send the .smil file to the browser which will launch the RealPlayer (recognizing the mime type) and pass the contents of the smil file on the RealPlayer which in turn will request the .rp file from the web server, and then reading the .rp file request the underlying .jpg files. Using a RealServer eliminates the need for both a .ram file and a .smil file; a .smil file, however, is always needed when additional sound or text is used.
• To check my statement about copyright protection, try to download the image files to your work station -- permission granted, I won't sue you for copy right violation :-)). It can be done without hacking into the maxweber server, but it takes a fairly good understanding of how all these files work together and where you finally can find path and file names of the underlying photos on the server. (Once you have this information, downloading is a piece of cake.) And this works only as long as a regular httpd server is used. You will not be able to capture/download multimedia material from commercial sites unless they deliberately make this this material available for recording (using RealPlayer Plus) or downloading. But, as mentioned above, there is no protection against simply capturing the screen (rather than downloading).

Example 3:

• If your work station has a sound card, it should have some basic sound software such as a "WAV player". It should also have a microphone. Typically, the microphones that come with a sound card (or the whole system) are pretty basic and may not be suitable for serious production. I had some trouble with my cheap mike to get a decent recording; it took some fiddling with the sound card setup. It pays to read the user guide for the sound card and check that the mike is properly installed. My Gateway station (P2-233 with 48 MB memory) came with an Ensoniq Audio PCI Wavetable Sound Card. Since mike adjustment is sound card specific, I will not go into any details.

Using your .wav player (or similar software) check the volume control during recording to have the right amount amplitude (meter should stay in the green or blue range). Replay recording to check quality. Wav files get large quickly, the 20 second recording used here takes over 400 KB.
• RealProducer converts any audio file in .wav or .au format to .rm format suitable for streaming and reducing size considerably; here the resulting .rm file is just 42 KB, about one tenth of the original size. Again, you play the .rm file locally to check the final result.
• As part of the (free) RealProducer G2 Authoring Kit comes the SMIL Presentation Wizard. This allows you to combine several media files -- like a slide show and a voice narrative. This is fairly easy to use, and several templates are provided as well. You may want to make some adjustments, e.g., matching the size of RealPlayer window to the size of your slides. A .smil file is a text file (though it should have the extension .smil or .smi -- depending on how the mime types in your web server are set up; a smart system administrator would allow both forms) and thus it can be edited with the help of any text editor or word processing software that can save file as ASCII text. A particularly useful multi-purpose editor is Ultra-Edit, now in version 6. This editor opens and edits any file (text, hex, exe, html) and you can easily open files in this editor by right-clicking on the file name in Windows Explorer. Registration of this shareware product costs you $30.

If you want to learn more about SMIL, a nice tutorial  became available on March 12, 1999 at the "Web Review" site. And there is also a rather costly (over $600) product that makes creating smil files easy and allows you to make efficient use of the available bandwidth, the Tag Composer. (It's like creating a regular web page in Notepad inserting all html tags explicitly versus using a user-friendly html editor like Netscape Composer, MS FrontPage, or the like. But the difference is in the price.)
• The final step is to set up the .ram file (see above).

RealSlideshow

• capability to add a text caption to each slide (makes it possible to forego an audio track and save bandwidth)
• customized layout of up to 4 areas (image, text caption, text, logo); the content of the last two will be the same for all slides
• support for .gif format (source images) and use of .png format (rather than .jpeg) in generated slide show -- can results in significant improvement in quality while reducing (!) file size; .png format, however, requires RealServer 6.1 beta 3 or better

• using a series of still photos of experiments in the sciences, of practical demonstrations in the health sciences, field work documentation in anthropology or sociology to just name a few possibilities
• using a series of "screen shots" to demonstrate use of online data bases (like Lexis-Nexis, InfoTrac, FirstSearch) or the use of specific computer programs, to take students on a virtual of the web, and much more

Note, that both tutorials require that your monitor is set to "16-bit color" (also referred to as "thousands of colors" or "65K colors). With just 256 colors (or "8 bit color") the text comes out as blue against black (almost impossible to read) and the screen shots look decidedly "psychodelic". This happens no matter what format (jpeg or png) RealSlideshow uses for the presentation. All my source graphics (screen shots) were saved as 8-bit color .gif files. There is no work around. On the other hand, only ancient video cards/monitors restrict a user to 8-bit color. However, some "broadcasting software" like LANSchool (used in lab settings to "broadcast" the contents of the instructor station to all student stations) cannot handle more then 8-bit color -- though all individual stations are capable of displaying higher color resolution. So, the problem is most likely to occur in a lab setting.
[end]

Example 4:

• Nothing much new, other than that the media files from example 1 and 2 are combined in another .smil file. Note, however, that you may experience trouble hearing the music the first time you access the link. Chances are that you only see the mute slide show. Wait till the very end, the music track is longer than the slide show. Towards the end, the music should become audible. Restart the clip from within the RealPlayer, the music should start right away.

I am not sure what causes this problem, maybe a bandwidth issue, maybe a problem due to the lack of a RealServer. The RealPlayer stores the component files in a memory cache, so the second time around the bandwidth or sequence problem does no longer exist. I am inclined to think that it is a server problem rather than a genuine bandwidth problem, but ...

Example 5:

• Similar to handling still images with RealPic, RealText allows to produce moving text. Such text can be displayed by itself or be combined with other media contents in a .smil file as in this example. Very easy to learn for anyone who once learnt html the hard way, explicitly using tags.

Example 6:

• This is a straightforward use of the RealProducer to convert a quicktime file in .mov format of 3.8 MB to streaming format, reducing file size to 90 KB and then setting up a web page and publishing this web page to the server. Pretty much a no brainer. In contrast to example 1, I chose to have the RealPlayer to pop up rather than embed it (a choice offered by RealProducer). As demonstrated above I could easily add a sound track (narration or music) to this animation.

More Examples:

• See example 6 as far as the conversion of the original .mov file is concerned. As another option, the clip can also be viewed with English subtitles using the technique first discussed in example 5. Here, however, we have all three channels involved: sound, video, and text.

Input via video capture card

I took advantage of a limited time offer by Real Systems which bundled the Basic Server Plus with a digital camera, a video capture card, and some other goodies -- all for some $1000. Now, this is not the fanciest camera around, but it does its job (example). As to input of VHS tape via standard VCR, this works quite well, too. Obviously, as there is some quality loss in the conversion to the "streaming" format, it is good to start with a high quality recording (good lighting, clear sound). Greg Crosbie and his crew from the AVS division of OICIT have shot some really good video of President Caputo delivering a greeting to visitors of the Hunter web site which I converted to RealFormat (example). A link to the clip may be added to the Hunter home page or the web page of the Office of the President in the future, for now President Caputo has agreed to have a link to this clip on this page. Production notes:

• The video capture card comes with its own software that allows capture in regular video formats (.mov, .avi). This software also allows to control his video input for contrast, brightness, tint, etc. The RealProducer takes these settings. Matter of fact, at least in my setup (which was sold as a bundle), one items from the options menu in RealProducer starts this software and allows to make these adjustments. I experienced some problems with this approach, however. In my setup, it works best to start the capture card software first, make the necessary adjustments, close this software, and then start the RealProducer to do the "encoding".
• Likewise, adjustments to the audio controls may be necessary to ensure proper level during recording. Details depend on the sound card you use; there are usually separate sets of controls for recording and playback. Takes a bit of fiddling like when recording audio via the microphone.
• The RealProducer Plus does not offer any editing features (the "Pro" version does), so it's a bit tricky to start and stop the clip at exactly the right point; no trimming options available.
• The final file size very much depends on the options chosen. For a 3 minute clip that is simultaneously optimize for 4 connection speeds (T1, DSL, 56K, 28K), the resulting file size (default frame size of 160x120 pixels) is about 11MB. But this is only a concern for hard disk space on the server box, as the size of the file actually downloaded for a particular connection speed is much smaller.

Live Broadcasts

To clarify the terminology, live broadcasts start and end at specific times and users join the broadcast in progress -- like switching on a regular TV; if a viewer is late for the start of a program he/she missed the beginning. In contrast, all "on demand" material is played from its very beginning at the time a viewer requests it. As with regular TV, such live broadcasts may not genuinely be live (even most live TV shows are shown tape-delayed, sometimes by hours, sometimes by weeks and months). However, here is one important distinction:

• simulated live broadcasts serve material previously encoded and stored on the server (the program consists of a playlist of on demand material) whereas in
• live broadcasts a video feed is captured on a remote station (via video capture card), encoded, and directly transferred to the server which simultaneously transmits this feed to requesting viewers; the feed captured on the remote station can either be truly live (coming from a video camera hooked to the video capture card) or taped (coming from a VCR connected to the video capture card)

However, I expect that a memory upgrade of the physical box will be necessary to serve even relatively small audiences effectively. The current license of the Basic server allows for 40 concurrent viewers, but even this may be beyond the current memory limitations. With the investment of some $200-300 for additional memory (bringing it to near 256MB), this problem should be easily solved. A serious problem may lie in limitations of the Hunter college backbone and/or Hunter's connection to the Internet. Only practical tests will tell -- and these have just started. So, check back in a month or so, for more details. If you want to play a more active role, consider being a test viewer, check out the live broadcast program schedule and tell me about your viewing experience. Thanks!

Call for exchange of information and experience

• multimedia presentations and delivery of course materials via the Web (web course pages)
• synchronous distance learning and asynchronous distance learning

If you are interested in the material presented here, especially if you have done similar explorations in the past or are about to engage in such, please get in touch, preferably via e-mail.