MPEG tutorial
When you have allot of related visual data to convey in the most efficient manor possible an animation could be a very valuable choice. The ability of the web to present visual images in line with text easily extends itself to movies, which are eye catching and sometimes more efficient in putting the point across.
The Cu-Ni phase diagram showing tie line calculations as well as composition is a good example of this type of movie. As you can see the end result of the movie is shown as a stand alone picture which displays allot of information, almost too much at one time for an introduction. To display the time relationship of the information in the phase diagram the format of an animation solved the problem.
The specific format that we used was the MPEG file type. There are several reasons for this. First it has become a standard format which can be viewed on several platforms: Mac, PC, and UNIX. It also provides a great amount of compression as far a physical size of the data. Our example used 53 individual cells totaling 10 Mb. After compression into a Quicktime movie it was about 2 Mb. The conversion to MPEG cut the size in half, which is very kind for people downloading at low baud rates.
The creation of the mpeg movie was very easy if you have access to the right tools. There is not just one way to make an mpeg but I will describe how we did it, which is very simple and straight forward.
The first step was to create a set of pictures in a sequential order with the goal in mind very similar to that of making a cartoon flip book. Once the images are created they must be placed into a directory all by themselves and named in numbered order, first frame a01.jpg, and so on: a02.jpg, ..., a10.jpg,...
Once this is done convert all of the files to the pict format. It is important when doing this to convert the files using a standard system pallet, such as the one that Adobe Photo Shop lets you select. Many programs may be used to do this conversion but if a standard system pallet is not chosen then other applications may or may not be able to understand the color in the picture and automatically convert it to gray scale as a default.
Now that you have the sequential ordered pict files you are ready to stack them into a movie type format. Using the program Spyglass View 2.1, or a newer version, select the file menu and from that take the "animate form disk" option. Select the first file in your series and the program does the rest. It will created a stacked format called a *.pics.
Now take this pics file into the program Convert to Movie. It will immediately ask you for a file name, select your pics file. You can now set variables in the about to be created movie such as the speed, frames/ second, and other related options. Select OK when this is done. Select "flatten movie" from the next screen then all that is left to do is name your new QuickTime mov file.
The final step in the process is to open the Sparkle MPEG player. Open your quick time mov file and select the "save as" option from the file menu. Under the "file type" option be sure that "MPEG MOVIE" is select and rename the file. Sparkle will now convert the mov to an mpeg which can be used on the web or in any presentation.
by Ben Hailer and Ken Jennings 1 May 96
http://www.eng.vt.edu/eng/materials/classes/MSE2094_NoteBook/
96ClassProj/sciviz/html/mpgtut.html
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