Figure 2

Randomly selected patches of various sizes sampled from leaf areas, avoiding leaf clapping grid and main veins. Patch sizes (pixels): (a) \(16 \times 16\), (b) \(24 \times 24\), (c) \(32 \times 32\), (d) \(40 \times 40\) and (e) \(48 \times 48\).