Visp is short for visual performer. It is an opensource visual performance application built with Adobe AIR . Here are a few of its key features and focuses:
1. Built with Adobe AIR using Flex and ActionScript 3.
2. Works on both Windows and Mac platforms.
3. Outputs a max resolution of 640 480 to a second screen.
4. Supports MIDI input via a separate Java application (watch the screencast).
5. Emphasis on performing the content rather than managing a complex user interface.
6. Use transitions to more seamlessly move from one piece of content to another.
7. Use up to two filters simultaneously to add post-render effects to your output.
8. Create your own custom content, transitions, and filters with ActionScript 3.
9. Geared toward generative content, not video clip triggering.
10. Source code is licensed under the GNU General Public License v2.
11. Intentionally feature-deprived to impose constraints, allowing you to focus on your content and creativity.

It is designed with an emphasis on performing visuals, where the role of the keyboard and mouse are downplayed. It is also geared toward generative visuals rather than short videoclip-based visuals.

Requirements:
* Adobe AIR

The license of this software is Free, you can free download and free use this audio utility software.