This is a java applet designed to aid in learning about the JPEG standard. It provides a visual of the process as well as substantial textual information explaining the process. The main menu contains three sub-menus: example, steps, and DCT. The example sub-menu shows an example of different levels of compression along with an explanation. The steps sub-menu demonstrates all the steps needed for compression. Finally, the DCT sub-menu shows an example of the process being performed on a picture.

This animation is very helpful in learning about JPEG still picture compression. It starts from the ground up and contains numerous pages of supporting information. This would be great as a lecture aide, or as a study tool or additional self-learning tool. The visuals are relatively clear in the explanation and steps portion of the animation. In addition, there are buttons to explore specific topics in more depth. The visual for the DCT portion of the animation is a little confusing to understand. Overall, this is a great tool for learning the entire process. It teaches from the start and doesn’t just show the process without explanations.

The contents are downloaded in a zip file, then compiled and run. The sub-menus can be accessed from the main menu. Controls within the sub-menus are very easy to use. The first sub-menu has controls for viewing different levels of compression for the picture given. The steps menu simply has buttons to traverse through the explanation slides. The DCT sub-menu allows you to select a portion of a picture and the still compression is performed on that selection.