Patent ID: 8131089
Filing Date: 2012-03-06
Classification: G06T

Abstract:
1. A method of compressing visibility data from a visibility database; the visibility data including cells of observation points in an observation space for observing predetermined objects and, for each cell of observation points, a list of the objects from among said predetermined objects that are potentially visible from that cell of observation points; and the visibility data being represented in the visibility database as at least a first visibility matrix of Boolean elements in which each row corresponds to a cell and each column corresponds to one of said predetermined objects, the Boolean elements respectively situated in an i th row and a j th column having one of a logic value 1 if the object belongs to the list of potentially visible objects associated with the cell and a logic value of 0 if the object does not belong to the list of potentially visible objects associated with the cell the method comprising: automatically detecting in the visibility database non-adjacent rows in a visibility matrix having a high number of common elements, and permutating rows to place rows detected as having a high number of common elements into a sequence to form a modified visibility matrix having a same number of rows as the visibility matrix; and automatically applying digital image coding to the Boolean elements of the modified visibility matrix to obtain a visibility data code, the Boolean elements of the modified visibility matrix forming pixels of the digital image for coding.