  Shape is an important aspects in recognizing plants. Several approaches have
been introduced to identify objects, including plants. Combination of geometric
features such as aspect ratio, compactness, and dispersion, or moments such as
moment invariants were usually used toidentify plants. In this research, a
comparative experiment of 4 methods to identify plants using shape features was
accomplished. Two approaches have never been used in plants identification yet,
Zernike moments and Polar Fourier Transform (PFT), were incorporated. The
experimental comparison was done on 52 kinds of plants with various shapes. The
result, PFT gave best performance with 64% in accuracy and outperformed the
other methods.
