A randomized iterative improvement algorithm for photomosaic generation

A photomosaic is an image assembled from smaller images called tiles. When a photomosaic is viewed from a distance, it resembles a desired target image. The process of photomosaic generation can be viewed as an optimization problem, where a set of tiles needs to be arranged to resemble a target image. We impose a constraint on the number of times a tile image can be repeated in a photomosaic. A randomized iterative improvement algorithm is used to generate photomosaics and the intermediate results are used to produce interesting animations. We show that the proposed technique is more efficient than genetic algorithm.

I. Introduction

Photomosaics are images assembled from smaller images known as tiles. When viewed from a distance, the individual tiles in a photomosaic lose their details and a desired target image is revealed. Photomosaics are digitized refinements of traditional mosaics, which are composed of many pieces of glass, stone or ceramic tiles of similar shapes and sizes to make up larger images.