Table 1. Definition of handcrafted features (according to the scikit-image documentation).
All of these features were extracted for each fluorescent channel (1-4) and region (nucleus, cytoplasm, and whole-cell) in the cell painting images.
| Feature name | Description | Category |
|---|---|---|
| Intensity max | Maximal pixel intensity inside the ROI | Intensity |
| Intensity mean | Mean pixel intensity inside the ROI | Intensity |
| Intensity min | Minimal pixel intensity inside the ROI | Intensity |
| Intensity Std | Standard deviation of the pixel intensities inside the ROI | Intensity |
| Area | Area of the ROI | Shape |
| Area convex | The area of the convex polygon that encloses the ROI | Shape |
| Area filled | Area of the ROI including all holes inside the ROI | Shape |
| Axis major length | The length of the major axis of the ellipse that has the same normalized second central moments as the region. | Shape |
| Axis minor length | The length of the minor axis of the ellipse that has the same normalized second central moments as the region. | Shape |
| Centroid | Coordinates of the center of the ROI | Shape |
| Eccentricity | Eccentricity of the ellipse that has the same second-moments as the ROI. | Shape |
| Equivalent diameter area | The diameter of a circle with the same area as the ROI. | Shape |
| Extent | The ratio of the Area of the ROI to the Area of the bounding box around the ROI. | Shape |
| Feret diameter max | The longest distance between points around a ROIs’ convex polygon. | Shape |
| Orientation | The angle between the X-axis and the major axis. | Shape |
| Perimeter | Length of the contour of the ROI | Shape |
| Perimeter crofton | Perimeter of the ROI approximated by the Crofton formula in four directions. | Shape |
| Solidity | The ratio of the number of pixels inside the ROI to the number of pixels of the convex polygon. | Shape |
| Contrast | The difference between the maximum intensity and minimum intensity pixel inside the ROI. | Texture |
| Dissimilarity | The average difference in pixel intensity between neighbouring pixels. | Texture |
| Homogeneity | Value for similarity of pixels in the ROI. | Texture |
| Energy | Value for the local change of pixel intensities in the ROI. | Texture |
| Correlation | Value for the linear dependency of pixels in the ROI. | Texture |
| ASM (angular second moment) | Value for the uniformity of pixel values in a ROI. | Texture |