Readings Flashcards
Physical realism
Replicates the visual stimulus of the scene (eg. the actual intensity of the light hitting your eyes)
Photo-realism
Replicates the visual response of the scene (eg. the colour and shapes of the scene)
Functional realism
Replicates the visual information of the scene
3 Varieties of Realism in Computer Graphics
- Physical realism
- Photo-realism
- Functional realism
Tone-reproduction
A major problem with photo-realism. Existing displays cannot reproduce range of light energy. Requires proper calibration. Could lead to quantitative visual analysis.
Efficient image synthesis
A problem with photo-realism. Many algorithms for photo-realism are very time and memory complex.
Two variables to measure for functional realism
- Accuracy: physically correct
2. Fidelity: does it tell the truth
Cue combination problem
The problem of perceiving the properties of scenes on the basis of the information available in images. Helpful visual cues are not always available (eg. shadows under diffuse illumination)
Probabilistic Inference
Framework being used for characterizing visual perception. (Bayes Theorem) P(S|I) = P(I|S)p(S)/p(I)
Scene property given image.
Visible Difference Predictors
An indication of what regions of two images are likely to be seen as different from one another.
2 Limitations of VDPs
- Threshold difference metrics in current VDPs are too strict to allow performance gains to produce realistic images at interactive rates.
- VDPs do not provide meaningful measures of many suprathreshold errors.
Functional Difference Predictors
An extension of VDPs that can show that two images are functionally equivalent even if they are visually different.
First animated films with computer graphics
- The Adventures of André & Wally B.
- Luxo Jr. (Academy Award nom.)
- Red’s Dream
- Tin Toy
- Toy Story
