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Defining Borders

Module by: Thomas Yeh. E-mail the author

Defining Borders

Overview

With the original cell picture, as shown below, it is very difficult to make out the cell borders due to the lack of contrast between the borders and the background of the image. Our first goal, before edge detection can even be done, is to create a sharper contrast between the borders and the background. This is shown in Figure 1.

Figure 1
Figure 1 (reflectance_455nm LED_adipose cells.png)

Thresholding

In order to create a higher contrast between a cell’s borders and the background, thresholding was utilized. Pixels of lower intensities, the background, were thrown out while pixels of higher intensities were kept. The IMADJUST command in Matlab allowed us to specify a threshold intensity and mapped all pixels below the threshold to zero. The result can be seen in Figure 2.

Figure 2
Figure 2 (threshold_image.jpg)

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Definition of a lens

Lenses

A lens is a custom view of the content in the repository. You can think of it as a fancy kind of list that will let you see content through the eyes of organizations and people you trust.

What is in a lens?

Lens makers point to materials (modules and collections), creating a guide that includes their own comments and descriptive tags about the content.

Who can create a lens?

Any individual member, a community, or a respected organization.

What are tags? tag icon

Tags are descriptors added by lens makers to help label content, attaching a vocabulary that is meaningful in the context of the lens.

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