Fig. 1. Comparison results before and after preprocessing. (a) Image pyramid; (b) original image; (c) image after preprocessing

Fig. 2. Grayscale variation image of local section of mesh. (a) Local image of mesh fabric; (b) distribution curve of gray value in local linear neighborhood

Fig. 3. Mesh fabric images with three different light levels. (a) Sample 1; (b) sample 2; (c) sample 3

Fig. 4. Results of segmenting sample 1 with different thresholds and its partial enlarged views. (a) T=20; (b) T=50; (c) T=100; (d) proposed algorithm; (e) partial enlargement of Fig. (a); (f) partial enlargement of Fig. (b); (g) partial enlargement of Fig. (c); (h) partial enlargement of Fig. (d)

Fig. 5. Results of segmenting sample 2 with different thresholds and its partial enlarged views. (a) T=20; (b) T=50; (c) T=100; (d) proposed algorithm; (e) partial enlargement of Fig. (a); (f) partial enlargement of Fig. (b); (g) partial enlargement of Fig. (c); (h) partial enlargement of Fig. (d)

Fig. 6. Results of segmenting sample 3 with different thresholds and its partial enlarged views. (a) T=20; (b) T=50; (c) T=100; (d) proposed algorithm; (e) partial enlargement of Fig. (a); (f) partial enlargement of Fig. (b); (g) partial enlargement of Fig. (c); (h) partial enlargement of Fig. (d)

Fig. 7. Results of segmenting sample 1 with different algorithms and its partial enlarged views. (a) Shading threshold algorithm; (b) marking watershed algorithm; proposed algorithm (c) before preprocessing, (d) after preprocessing; (e) partial enlargement of Fig. (a); (f) partial enlargement of Fig. (b); (g) partial enlargement of Fig. (c); (h) partial enlargement of Fig. (d)

Fig. 8. Results of segmenting sample 2 with different algorithms and its partial enlarged segmenting. (a) Shading threshold algorithm; (b) marking watershed algorithm; proposed algorithm (c) before preprocessing, (d) after preprocessing; (e) partial enlargement of Fig. (a); (f) partial enlargement of Fig. (b); (g) partial enlargement of Fig. (c); (h) partial enlargement of Fig. (d)

Fig. 9. Results of segmenting sample 3 with different algorithms and its partial enlarged views. (a) Shading threshold algorithm; (b) marking watershed algorithm; proposed algorithm (c) before preprocessing, (d) after preprocessing; (e) partial enlargement of Fig. (a); (f) partial enlargement of Fig. (b); (g) partial enlargement of Fig. (c); (h) partial enlargement of Fig. (d)

Table 1. Number of mesh segmentation errors and segmentation error rate

Table 2. Comparison of mesh segmentation results of different algorithms