A Survey of 2D and 3D Shape Descriptors

3D objects play a vital role in computer games, movies, TV, engineering design, and biological sciences. Researchers have studied 3D object retrieval techniques using 2D and 3D shape descriptors in the last several decades. In this paper, some of the most popular shape descriptors are reviewed. We first discuss the important criteria for a good shape descriptor. Then, we classify 2D and 3D shape descriptors into several categories. For each category, we review the state-of-the-art techniques along with their advantages and disadvantages. We also examine the recent contributions and improvements in these techniques and provide a comparison with other successful techniques based on previous literature and surveys. Finally we discuss the possible future directions.