Vvvv is described as 'vvvv is a graphical programming environment for easy prototyping and development. It is designed to facilitate the handling of large media environments with physical interfaces, real-time motion graphics, audio and video that can interact with many users simultaneously' and is an app. There are more than 10 alternatives to Vvvv for Windows, Mac, Linux, Online / Web-based and Self-Hosted solutions. The best alternative is Processing, which is both free and Open Source. Other great apps like Vvvv are Pure Data, TouchDesigner, Isadora and Cinder.
Processing is an open source programming environment and library built to handle images, animation, and interactivity. It is used by students, artists, designers, researchers, and hobbyists for learning to code, prototyping, and producing full applications.
Pd (aka Pure Data) is a real-time graphical programming environment for audio, video, and graphical processing. It is the third major branch of the family of patcher programming languages known as Max (Max/FTS, ISPW Max, Max/MSP, jMax, etc.
TouchDesigner is a complete authoring tool for building interactive 3D art, visualizations, prototypes and UIs. Derivative makes and supports TouchDesigner and offers their services to do custom production using TouchDesigner.
openFrameworks is an open source C++ toolkit designed to assist the creative process by providing a simple and intuitive framework for experimentation. The toolkit is designed to work as a general purpose glue, and wraps together several commonly used libraries, including:
Orca is an Esoteric Programming Language and live-coding environment for musical experimentation. In Orca, each letter of the alphabet is an operation, lowercase letters operate on bang, uppercase letters operate each frame.
VDMX5 was created from the ground up to meet the demands of realtime video performance. Built around a robust data processing architecture it was designed to be used with whatever hardware- or software- you've got available.