Evolutionary Art with Multiple Expression Programming By Quentin Freeman

System Overview Goal –To visualize images in real time as they evolve while allowing the user total control over the genetic algorithm. Why –Allow images to be generated using a good set of functions to reduce the amount of “static” images contain. –Most Evolutionary art programs use really basic functions which introduce a lot of static and take thousands of generations to find “good” images.

Chromosome Data Structure Each chromosome is represented by an array of genes. –Each gene contains 2 pointers, a function, and a parameter value. –Pointers index any gene that came before the current. It can also point to the X and Y pixel coordinate values. –Functions are a value from 0 to 1-MAX number of functions. –Parameter is a value from 0 – 255, these are used as extra input values into the function. –There is a special gene at the end of the chromosome which is the pointers for the RGB values.

Chromosome Data Structure Example of a chromosome with 3 genes.

Chromosome Data Structure Advantages –Pointers allow a chromosome which have the exact same function and parameters to be mapped many different ways. –The number and exact definition of functions is left out of the data structure for maximum flexability. For example, its easy to swap function sets.

Complex vs Basic functions

20 generations of searching Basic Complex

Example of mutation Starting image  Resulting image

Example of crossover Parent 1 + Parent 2 = Child

Program Flow

Design Process Data structures and Algorithms went through several revisions. –Original chromosome Data structure used strings instead of integers. Had to redesign because of speed issues –At one point function calculations were using doubles Had to restrict to integers for speed

Conclusion Successfully created a real time Evolutionary Art program. –The animator for images had to be dropped cause of time constraints. Primary loss of time was the result of 1-2 bugs that took a tremendous amount of time to fix. What I learned –Optimizing code that gets run 100,000 times for each image. –Learned more about using and manipulating java GUI

Any Questions?