Figures & data
Figure 1 The flowchart of proposed approach.
Figure 2 Description of 2D histogram of array (L × L). (a) 2D histogram divided into four blocks: A for the background, B for the objects, and the block C and D for the image edges and noises; (b) The Block B are divided into two bright parts, B 1 and B 2; (c) The Block D are divided into two dark parts, D 1 and D 2.
Figure 3 S-function and Z-function. (a) A genral S-function (central solid line), the left limitation function (left dashline) when a → 0, and the right limitation (right dashline) when c → L; (b) A genral Z-function (central solid line), the left limitation function (left dashline) when a → 0, and the right limitation (right dashline) when c → L.
Figure 4 Results of the proposed approach with a strong front light. (a) A test image under a strong front light condition; (b) Recognition with + a* channel, where some small parts which belong to dark green leaves and sky, directly turn black and their gray-levels remain 0, and ripe Fuji apples and the reflective edges of leaves are highly lightened; (c) Grayscale histogram of (b); (d) Grayscale two-dimensional histogram of (b); (e) Segmental resulting with fuzzy two-dimensional entropy based on optimized GA, where most backgrounds are removed, and the fragments are composed of only the reflective edges of leaves; (f) Morphological operation resulting of (e), where two reflective branches on the top are left.
Figure 5 Results of proposed approach with shadows and occluded leaves and branches. (a) A test image with shadows and occluded leaves and branches; (b) Recognition with + a* channel, where some small parts which belong to green leaves and branches, directly turn black and their gray-levels remain 0, and ripe Fuji apples are well preserved; (c) Grayscale histogram of (b); (d) Grayscale two-dimensional histogram of (b); (e) Segmental resulting with fuzzy two-dimensional entropy based on optimized GA, where the most majority of backgrounds are removed; (f) Morphological operation resulting of (e), where even the occluded red apples are well preserved.
