Quicktime VR

2. Introducing techniques:

2.1. Modelling and Rendering:

For each sorrounding or object there are 6 degrees of freedom, like the sides of a cube to move it through a three dimensional space. Modelling and Rendering is supported by special software products making it possible to create scenes from self-made objects and spaces. Three main problems remain:

• Creating objects and spaces is a manual process (wastes time and resources)
• Scene complexity (modelling every detail is impossible, rendering much details costs performance and hardware recources)
• limited availabilty (results from point 2, special hardware and software are expensive)

• This results in limitations not possible to get rid of without changing the technique. Faster and cheaper hardware eliminates the third point and partially satisfies the first. Scene complexity exists as an unlimited factor, not getting satisfied at any time. Manually implemting details is always making a compromise.

2.2. Branching Movies:

• Another approach to synthesize and navigate through a virtual environment is branching movies, a technique priviously used in game industry. The scene is a construct of a net of paths to walk on connected to each other on well-defined branching points. The images are playbacked from an analog or digital videoplayer. The main problems remaining:
  • limited navigability and interaction (restricted by the complexity of path-connections)
  • high amount of storage space for movie data
  • The advantages are:
  • greatest complexity
  • inexpensive, common in- and output devices

2.3. Objectives:

• A new approach is to define objects as special artifacts of a virtual environment. Using special storage techniques described later it is possible to focus on details of an object. Speed and Quality are the main features which should be supported by a special object viewing system.

2.4. Summary:

For the implementation of a virtual reality framework, the developers of Quicktime VR decided to design the system as open as possible. Support for Rendering and Modelling is necessary for implementing not yet existing objects and scenes. Branching Movies have the capability to fulfill real-time constraints and complexity of existing environments. Non-existing objects can also be constructed mixing both techniques by building a model of the objects and scenes and making photographies or films afterwards. Another design aspect was to implement an real-time image processing engine, flexible enough to consider different speed on hardware level. So the following mixture built the base for implementation of Quicktime VR:

• allow film-sequences, photos or rendered images (as open .TIFF format) to describe data for 360° panorama or object view
• orientation independence within panoramas (implemented as a cylindrical .TIFF image)
• real-time processing on different speed (makes it possible to present 0 to 30 and more image-frames per second)

1. Abstractation of the topic

3. Techical Details

4. How's Quicktime implemented

5. Future Directions

Back to Overview