Fifth International School On Mind, Brain And Education

2010, August 1-6

Learning, Arts,
and the Brain

Directors: Antonio M. Battro and Kurt W. Fischer
Program officer: María Lourdes Majdalani

Abstract: Horacio Reggini
National Academy of Exact Physical and Natural Sciences. ARGENTINA

Put a brain in your camera: non-standard computer images
Ever since the geometry of central perspective was developed in the 15th century, it has been observed that mechanical application of the procedure leads to effects of distortion and exaggeration of shapes and sizes, which often make the result look unnatural. Similar observations are made with the optical projections obtained in photography and video. Artists have intuitively corrected these perceptual shortcomings of perspective. My own attempts are in the nature of the “refinements” known from the practice of architecture and painting since the Greek temples and found also in the Renaissance.
In standard perspective each point of an object or scene is projected upon a plane by means of a bundle of straight projection rays departing from a viewpoint. In the non-standard perspective that I have developed, I follow a similar procedure, except that I replace the straight projection rays of standard perspective with special curved ones. By replacing the straight lines with curves of various degrees I am attempting to attenuate distortions and make the projections look more natural. This model has been validated by visual experiments in the open field.
I use in the proposed non-standard perspective a parameter “i”, or image index, to give curvature to the projection rays. Assumed curved projection rays, in comparison with the straight rays of standard conical perspective (i=0) emerging from same viewpoint, make smaller the dimensions perpendicular to the principal ray of near parts and bigger the far ones; or in other words, frontal dimensions of near objects are diminished, and those of distant ones are enlarged in the generated images, in comparison to what happens in standard perspective.
Adopting mentioned projection rays, I have prepared a computer program for depicting three-dimensional objects or scenes on computer-driven plane displays according to different indexes. The proposed index image adds a new facility to the broad and creative field of image displaying and gives rise to a new mode of graphics in two-dimensional space.
Greats artists (Durer, Rafael, Veronese) attempted to overcome visual distortions generated by standard conical perspective using pre-computational models. The next step will integrate the non-standard perspective into a new kind of digital camera which will allow the user to select a preferred perspective by changing the index.