Whats the relation between Quartz Composer, Core Image and OpenGL?
Quartz Composer is a high level modular authoring environment that uses Core Image and OpenGL to render a scene. You can still do many effects such as particles, mapping video to geometry etc without using Core Image. If your computers grahics card does not support accelerated Core Image filters then QC will render them in an altivec fallback mode but it will probably be too slow for realtime video performance.
