10.5 Object Measurement
Considerations
Image analysis can provide several measures of an object’s structure by defining
its characteristics in terms of area, perimeter, elongation, compactness, contrast,
and texture, as shown in Table 10.1. The table shows object measures computed
for different particle types from the urinary sediment, including, red blood cells
(RBC), calcium oxalate crystals (CAOX), white blood cells (WBC), bacteria
(BACT), granular casts (GRAN), cellular cast (CCST), squamous epithelial cells
(SQEP), sperm (SPRM), and hyphae yeast (HYST). It is clear that size measures
such as area and perimeter can be used to distinguish smaller particles, such as
RBC, from the larger cells types, such as SQEP. Similarly, the elongation and
compactness ...