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5.8 Cell Walls
5.8
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Cell Walls
Figure 5.15: Microscope image of wooden cells.
You can clearly see the single cells and the discontinuity that is caused by the stopped growing in winter.
Extracting cell walls is simple because they are significantly darker. The remaining “difficulty” lies in
the computation of the distribution in growth direction, i.e., along the image x-axis. First, we define the
width of the window over which the cell distribution is computed by assigning it to the variable X in
the program. Then we fetch the image size using get_image_pointer1 to get the corresponding loop
parameters. The broader the search range, the stronger the smoothing during the measurement.
Now the loop starts from the “left” side to compute the whole image. The ratio of the area of the cell
walls and a rectangle of width X is computed for every value of the loop variable i. The number of pixels
belonging to a cell wall (Area) is determined by area_center. This value is transformed to percent for
the output.
Examples
File name: wood_cells.dev
In this example we will examine the alteration of the cell wall’s proportion during a tree’s growth. The
input image is a microscope view of wooden cells (see figure 5.15).