Pure Data!

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:

A real time audio synthesis engine, and an object-oriented programming language specialised for music.

ChucK is a programming language for real-time sound synthesis and music creation. ChucK presents a unique time-based, concurrent programming model that's precise and expressive (we call this strongly-timed), dynamic control rates, and the ability to add and modify code on-the-fly. In addition, ChucK supports MIDI, OpenSoundControl, HID device, and multi-channel audio. It's fun and easy to learn, and offers composers, researchers, and performers a powerful programming tool for building and experimenting with complex audio synthesis/analysis programs, and real-time interactive music. »

Quartz Composer is a node-based visual programming language provided as part of the Xcode development environment in Mac OS X for processing and rendering graphical data.Quartz Composer uses OpenGL (including GLSL), OpenCL (only in Mac OS X 10.6 and later), Core Image, Core Video, JavaScript, and other technologies to build an API and a developer tool around a simple visual programming paradigm. Apple has embedded Quartz technologies deeply into the operating system. Compositions created in Quartz Composer can be played standalone in any QuickTime-aware application (although only on Mac OS X 10.4 and later), as a system Screen Saver, as an iTunes Visualizer, from inside the Quartz Composer application, or can be embedded into a Cocoa or Carbon application via supplied user interface widgets. Because Quartz Composer makes extensive use of hardware acceleration and pixel shaders, it is recommended to have a graphics card with at least 32 MB of VRAM. While Quartz Composer is included with the iPhone SDK, there is currently no way of running Quartz Compositions on iOS devices. »

Interactive visual programming environment for music, audio, and media

Vuo lets media creators make interactive animations, exhibits, performances, and professional-grade media projects by connecting up simple building blocks. Media creators can use these blocks to manipulate audio input, images, layers, videos, and 2D + 3D graphics, as well as record high-quality video of the results.

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.

Plogue Bidule is a modular audio software with full VST, Audio Unit and Rewire support.

Fugio (pronounced foo-gee-oh) is an open visual programming system for building digital art and creative projects quickly, with no programming experience required.

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.

Isadora is the award winning, interactive media presentation tool that allows you to follow your artistic impulse. Whether you are an artist, designer, performer, or VJ, you can quickly and easily harness the limitless potential of digital media and real-time interactivity with Isadora.

Native Instruments Reaktor is a virtual, modular synthesis platform.

Run your Pure Data patches on Android with native GUIs emulated.

Usine Hollyhock is a modular environment for live music and real-time installations. You can create and customize your live set to fit it exactly to your needs. Designed for spontaneous electronic music creation, including live sampling, effect processing, or sound design.

Csound is a sound design, music synthesis and signal processing system, providing facilities for composition and performance over a wide range of platforms. It is not restricted to any style of music, having been used for many years in the creation of classical, pop, techno, ambient, experimental, and (of course) computer music, as well as music for film and television.