AssaySoft's proprietary image analysis method utilizes topology, which is the science of continuity and connectedness that studies spatial relations within the image.

An image pixel is defined to have 4 vertices (corners), 4 edges, and one face. Algebraic topology uses algebraic operations with these objects to capture and count the number of completed cycles - circular sequences of edges. The completion of a cycle indicates the presence of a cell.

In binary images, this approach allows us to find cells as black objects with white background or white objects with black background. In the case of gray scale, we count dark objects with light background and light objects with dark background.

The types of images for which our algorithm is most suited are those that have mostly 2-dimensional features (rather than 2D images of 3D objects) such as images of cells under a microscope.

The topological nature of the algorithm makes it especially suitable for cell counting for the following reasons:

• • The count of cells is independent of their locations.

• • The measurements of cells are independent of their orientations with respect to the image grid.

• • The cells and other features are captured with no deformation, smoothing, blurring or approximation.
  
  

For a detailed description of the methods and algorithms we apply, see Computer Vision Primer.