Table Of Contents

Previous topic

draw

Next topic

Yayi core python extensions

This Page

Examples

We describe here some examples of use of the python bindings of Yayi. We hope you will find these snippets useful.

Note

We suppose Yayi installed!

Venation network of a leaf

Segmenting the leaf against the background

As described in introduction, the images are quite easy to segment. To do that, we simply use the color information of the leaf against the background. This is easily expressed in the HLS color space, where the hue of the leaf should be (approximately) between -60 and 180, and

Here is the code:

import Yayi.color_utilities as CO
import Yayi.morpho_utilities as MU

# transforming the image into the HLS l_1 color space
im_hls = CO.HLS1FromRGB(im_color)

# thresholding the hue component taking care of the circularity of the channel
t_color_h = CO.ThresholdCircularDomainDegres(MU.colorGetChannel(im_hls, 0), -60, 120 + 60)

# thresholding the saturation component
t_color_s = MU.MThresh_255(MU.colorGetChannel(im_hls, 2), 10.0/255, 1)

# taking the intersection of these two masks
immask = MU.AAnd(t_color_h, t_color_s)

And now we have a fairly good approximation of the mask of the leaf.

Extracting the venations

We will perform successive line opening in every directions in order to extract the venations of the leave.