Updated on: Friday, 12-Sep-2014 13:33:01 EDT
The following are guidelines that I propose for taking a course online, almost entirely based on my experiences since 1997.
In earlier status reports I discussed the daunting task of taking a full course on-line for credit. Even a long-established course has to be written in the proper lesson-plan format before it can be converted to HTML (HyperText Markup Language) format for use on a Web browser and edited with audio and other linked files to make an effective on-line course. For most faculty this writing competes with teaching, research, graduate committee and departmental assignments, etc., so it cannot be done quickly. Based on my experience, I suggest faculty approach the task using a three-stage model (obviously, some of these stages may be combined, and the third stage is primarily for those who offer their courses worldwide through DELTA, for instance):
Originally, I thought that the very heavy memory and speed demands placed on the computer by the software used to produce the course meant that faculty putting a course online would need vastly more than students would need to take the course, but with the very rapid advance in computer capabilities, current MACINTOSH and PC computers will be more than enough. So what I had listed as minimum hardware and software in the originial report, even as late as 2007, is now easily provided.,
The following are suggestions for Mac and Windows HTML software for converting text to, and editing of, HTML and for producing and editing graphics and audio files.
Listed below are some of the strategies I found useful in constructing my course. I chose these strategies with one goal in mind: to present pleasing and easily navigated web pages; and to use technology (graphics and audio and video) only when it enhances the learning experience.
As described in the Course Description - Part 3 of this report, I divided my course into thirteen lessons (labeled starting with Chapter 3 and ending with Chapter 16). I found it beneficial to break the longer lessons into subparts -- this made it easier for me to prepare a class schedule (see, for instance classschedule.html), and it provided a smaller file for the students to download and print.
During the early stages of the conversion of my written course material into html, I designated the audio and graphics files in all of my lesson folders with the same name (audio and graphics, respectively) but often made mistakes in linking the proper audio and graphics to the lesson in which they were to be included. Therefore, I found it desireable to name the audio and graphics folders with the same number as the lessson folder in which they reside (e.g., lesson07, audio07, graphics07). I also named the course audio and graphics files courseaudio and coursegraphics for the same reason.
Finally, I organized and keep the course on my computer in the following alphabetical hierarchy (when a html is included, it is a file; when it is not it is a folder) - I include a representative set of files and folders, and am using one of my larger lessons as an example:
COURSE (main folder that holds all subfolders and files)
courseaudio (all audio files used outside of the individual lessons)
coursevideo (all video files used anywhere in the lessons)
coursegraphics (graphics files used outside of the individual lessons or used commonly in all lessons -- such as sound and return 'buttons', and non-standard space bars, etc.)
index.html (this is main course page, from which all other parts of the course can be accessed)
lessononline.html (gives links to lessons)
Chapter07 (folder that contains following folders and links):audio07 (all audio files for this lesson)
graphics07 (all graphics for this lesson)
index.html (this is main lesson page that includes reading assignment, course objectives, etc. for this particular lesson)
part1.html (sub part 1 for breaking content into small bites)
part2.html (sub part 2 for breaking content into small bites)
studyguide1.html (study guide for Part 1 of course - there are four such studyguides)
Note the use of the index.html files both in the COURSE folder and the lesson07 folder. Web browsers will recognize the index automatically, without having to include it explicity in the URL. For instance, you only have to use http://legacy.ncsu.edu/MEA200 as the URL for my course -- the /index.html is assumed.
Note also that you should not use spaces in the titles, and the lesson, audio, graphics and html files are all lower case. This makes downloading the files more compatible for UNIX-based computers. Note finally that to keep the lessons in order when shown in list format on my computer, I write each single digit number below 10 as a two digit number with a 0 preceding.
I do not recommend using frames on the lesson pages. Students with minimum hardware (e.g., small or single scan monitor) and software capabilities may not be able to download framed lesson properly. Also, I discovered that all the students thus far print the pages for detailed study, and printing framed pages is problematic.
I used the software supplied by Microtek with its ScanMaker 2850 scanner to import files into Adobe Photoshop 5.0 on my MacIntosh G5. I set the color mode to RGB, scale to 100% and optimize for quality rather than speed. I also set the scan rate at 145 bpi and then, before adjusting the sharpness, brightnes and/or constrast, reduce the size to 72 bpi. This setting gives an adequately clear image without creating an unreasonably large file. Then the image is further reduced when the RGB image is compressed (by indexing the color) into a GIF file that can be linked to your html page. For instance, a typical scanned image in RGB may be more than 500 KB in size, but will be reduced by more than a fourth when the color is indexed.
I now use a HP Scanjet G4010 scanner (and its supplied software) and Photoshop CS2.
Management of these large-sized scanned image files can be problematic if you do not have a large amount of disk space. I routinely transfered the RGB files to 100MB zip disks so that only the GIF files remain, but most computers now have more than enough memory.
I recorded my audio files in three ways. One, I used an inexpensive Radio Shack cassette tape recorder (with attached belt clip and lapel microphone) to record some of my lectures, then used a non-impedance coaxial cable to input the audio into my computer as a SoundEdit 16 file for editing and conditioning (with OS X, that is now done using Classic OS). I did not use the voice-activated feature of the recorder because the start-up delay in recording clips the first part of each sound segment. I also put the lapel microphone about half-way down the front of my shirt, and record at normal speed and a volume setting of about 4 to 5 (to keep from clipping the amplitude). Two, I used the microphone supplied by Macintosh and set on top of the monitor (at a distance of about 14 inches from my mouth) and recorded directly into a SoundEdit 16 file. Three, I used the audio portion of my video-taped lectures recorded by OIT (now DELTA).
After editing, I saved the sound as an Audio IFF file.
I edited the sound files with two basic effects:
Smooth. This removes sharp edges, clicks, and pops. The Smooth effect simulates a low-pass filter that cuts out many of the higher frequencies from a selection. This command is used to eliminate hiss and static from a sound.
Normalize. This effect amplifies a sound to its maximum value without clipping or distortion. This is similar to applying an automatic gain control. Use this effect to raise the amplitude of a sound to its highest distortion-free level without time-consuming, manual amplitude adjustments. If a sound contains more than one track, SoundEdit 16 recalculates the normalize factor for each track. One hundred percent of maximum amplifies the sound to its maximum value without clipping or distortion. SoundEdit 16 will increase the amplitude until one or more samples reach their maximum distortion-free value. A sound that is already clipped will not be amplified. To adjust the amplitude of the sound to a fraction of its maximum, distortion-free value, enter a value less than 100 percent.
I compressed the Audio IFF files using a RealProducer Encoder with the narrow response feature optimized for a 56 KB modem. This response setting improves clarity of speech-intensive noisy signals and reduces the frequencey response to about 4 kHz (from the 44 kHz of the recorded sound). Most importantly, it also compresses a 3 minute audio file from over 15 MB in size to about 350 KB.
Note: Now all my audio files have been converted to .mp3 files.
Note: Now with the demise of NCSU support for Real Video, and to provide video files that my students could access, I had to retrieve all my uncompressed QT movies (stored on 8 DVDs) and compress them using QT 7 Pro on my MacBook Pro (with OS 10.7XX). These files are much larger than the compressed files using Real Video (the largest being 195MB), but the compressed videos are easily downloaded on today's computers, and start almost immediately (akin to streaming) without having to wait to download the full file.
I am leaving what follows intact because it still contains good choices for editing using iMovie. In the future, I can do all that I describe below by capturing portions of my lectures into my MacBook Pro directly from the DVD provided by DELTA. When finished with a movie, I can then save as a compressed QT file using that feature which is imbedded into the OS.
I had VHS video recordings (now they are on DVD) of all my lectures (from the video course I taught during one 5 week summer term), and selected portions of those tapes to edit and compress for inclusion on my web course pages, because seeing concepts developed enhances learning. To do so required a significant upgrading of my computer - I finally got a MacIntosh G5 computer that includes the 'simple-to-use' iMovie software, a TV-VCR combination set and a Dazzle* Hollywood DV-Bridge to import the analog VHS clips and convert them to digitial files.
My strategy for selecting video clips was to minimize me as a 'talking-head', by focusing on those parts of my lectures that showed the development of a concept that is difficult to do on a 'static' page. This included, for example, the development of graphs for such things as the density anomaly for water, and the estimation of geostrophic currents from a knowledge of the density of ocean water and the relative slope that is produced. Both these concepts are best learned seeing them developed on graph paper (as in the case of density anomaly) or being able to view the sea surface slope (as in the case of geostrophic currents) from 3-D props, etc.).
The biggest problem in using streaming video is the size of digitized movies and even the final compressed movies. As you can see below in a comparison I conducted, many uncompressed files are as large as 1.9 GB in size (that is the largest QuickTime movie the software allows you to make -- I had to break one file into two to get the size down). A typical compressed file optimized for the higher connection speed is at least 27 MB, so including a dozen or more in your web pages will require a large course locker quota.
I used the iMovie software to import the VHS video clips and edit the digital clips. The book iMovie: The Missing Manual was invaluable - the instructions resident in the G5 computer are not user friendly. This book contains much more than you need if you already have VHS tapes available, but the book is an easy read and was very helpful. Of particular use was Part 2. Video files were imported as clips and stored on a 'shelf' on the upper right hand side of the screen, much as color slides are placed on a lighted viewing board. Each clip shows the first frame in the clip and the duration of the clip. The maximum length of a clip is 9 minutes and 28 seconds (about 2 GB of file space). If you import a file with a duration longer than that, iMovie automatically and smoothly begins a second clip. All editing of the clips was done while the clips are on the 'shelf'. If you have more than one clip (say Clip 02), you need to move in down a couple of rows on the 'shelf' to allow for multiple edited clips of Clip 01 (see below).
I edited the clips as follows:
Selecting and editing clips. Selecting one of the on the clips from the 'shelf' displays it on the large monitor on the upper left hand side of iMovie. Below the monitor are the Scrubber bar (along which a Playhead marker moves) and play, stop, pause and rewind and fast forward buttons for use in editing the clip. Editing each clip is a little tricky, but once learned is very easy (much more so than use of a professional movie editor such as Premier). You will need to learn the difference between the chopping of a segment out of the middle of a clip (which produces two clips, such as Clip 01/01 and Clip 01/02) or the cropping off of the ends of clips (which preserves a single Clip 01). Once editing is completed, I drag the clips in sequence to the 'movie board' on the bottom the screen.
Creating titles. I didn't use transitions between clips (as one would if using slides, for instance) but do use some creativity in presenting the title to the iMovie. I created a still image using Photoshop 5.0 that I use for the 'title-page' in all my iMovies. This image was imported and stored in the upper left hand corner of the 'shelf'. Then I selected Titles from the tool bar just below the 'shelf', and set the duration of the clip to at least 8 seconds. I then selected IMPACT as the font (bold, easily readable letters on streaming video displays), and 'Bounce to Center' as the effect (all shown below).
Once the title was completed, I dragged the title clip to the beginning of the movie board and it was rendered (it takes about 2 minutes).
I exported iMovie as a non-compressed QuickTime movie. I chose not to compress the iMovie during export to QuickTime so that I could have more control over the compression using Real Producer, and use Real Producer because, in my experience, it is easier for my students to down-load Real Player than QuickTime to their computers (and because it was highly recommended by Hal Meeks, NCSU's resident guru for all things multimedia). I export to QuickTime using the Expert settings, shown below in the figure.
I then compressed the QuickTime movie using Real Producer, with the following settings:
File Type: SureStream (TM), which gives the maximum flexibility for multi-rate streaming.
Target Audience: I optimize the streaming for two different connections (56K Modem for about one fourth of students taking course through DELTA at the time; and Corporate LAN for resident students living in dorms or who have access to NCSU public computer labs, or those off-campus who have DSL/Cable Modems). As shown in summary below, optimizing a 1.68 GB uncompressed QuickTime movie for different connections produces widely divergent file sizes.
Optimized for 56KB
Optimized for Corp LAN
Optimized for 256KB
Optimized for 512KB
Clearly the 512 KB is unacceptably large (10 of those would require a 1 G locker quota for my web course), and the 256 KB also may be too big. Using realplayer, I clicked repeatedly back and forth between the last three videos listed in an attempt to compare the relative 'quality' of the videos, and found no apparent improvement at the two higher connection speeds, so I provided all streaming video files in two formats - those optimized for 56KB and those optimized for Corp LAN. Note: currently, because of greatly increased band width, I unclude only the high speed formats).
Audio Format: Voice only.
Video Quality: Smoothest Motion Video, which is best for clips that contain limited action.
Real Producer also allows you to title and describe your video, as shown below:
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