# bbox

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Description: This method implements the bbox filter. It removes all components with a bounding-box with dimensions smaller than dx, dy, and dz in case of 3D images.

Constructor signature: MorphTreeAlpha.bbox(dx, dy, dz = 0)

Input:
• dx, int. dx threshold value.
• dy, int. dy threshold value.
• dz, int. dz threshold value, its value is considered only in the case of 3D images.

Output:

# Python Implementation

``` 1 def bbox(self, dx, dy, dz = 0):
2     """
3     Contracts all nodes with bounding box less than 'dx' by 'dy'
4     """
5     ddx = self.node_array[7,:] - self.node_array[6,:] + 1
6     ddy = self.node_array[10,:] - self.node_array[9,:] + 1
7     if self.node_index.ndim == 2:
8         self.prune((ddx < dx) & (ddy < dy))
9     else:
10         ddz = self.node_array[13,:] - self.node_array[12,:] + 1
11         self.prune((ddx < dx) & (ddy < dy) & (ddz < dz))
12     return self
```

# Example

``` 1 from iamxt import MorphTreeAlpha
2 import numpy as np
3
4 img = np.array([[100, 100, 100, 0,   0,   0,   0,   0],\
5                 [150, 150, 150, 150, 150, 150, 150, 150],\
6                 [150, 160, 190, 150, 200, 200, 229, 150], \
7                 [150, 185, 255, 150, 200, 230, 200, 150],\
8                 [150, 180, 200, 150, 215, 229, 200, 150],\
9                 [150, 150, 150, 150, 150, 150, 150, 150],\
10                 [50,  50,  0,   0,   0,   0,   0,   0]], dtype = np.uint8)
11
12
13 Bc = np.array([[0,1,0],\
14                [1,1,1],\
15                [0,1,0]], dtype = bool)
16
17
18 morph_tree = MorphTreeAlpha(img,Bc)
19
20 g= morph_tree.generateGraph()
21 mmgraphviz(g, title='Morph-tree')
22
23 morph_tree = MorphTreeAlpha(img,Bc)
24 morph_tree.bbox(dx = 2, dy = 2)
25
26 g= morph_tree.generateGraph()
27 mmgraphviz(g, title='Morph-tree after filtering the nodes with dx < 2 and dy < 2')
```