All twelve sit in the Basic Operations Module under Threshold and Compare. Pick by what you have and what you need back.
| Your input and goal | Operation |
|---|---|
| One grayscale imageLoading...; a mask of pixels above a value | Compare, with Compare Mode = Greater (or Greater or Equal) |
| One grayscale image; a mask of pixels below, or not equal to, a value | Compare, with Less, Less or equal, or Not equal |
| One grayscale image; a mask of pixels inside an intensity band | Compare - inside interval |
| One grayscale image; a mask of pixels outside a band | Compare - outside interval |
| One grayscale image, and you don't know the right value | OtsuLoading..., or Otsu (with range) when noise or shading spoils the two-peak shape; then look at the result |
| A color image; a mask where every channel passes its value or band | Compare (RGB), Compare - inside interval (RGB) or Compare - outside interval (RGB) |
| Keep the image, but replace values past a cutoff, such as flooring dim background or capping bright spots | Threshold or Threshold - LT, GT (RGB versions for color) |
| Two images; a mask where one is brighter than the other | Not in this group. Subtract images (Arithmetic) gives Image 2 minus Image 1, which Compare can then test against 0. |
Compare starts at Threshold 0 with Compare Mode Less. On an ordinary 8-bit image, no pixel is less than 0, so the default mask comes out empty until you set both. Include interval limits (default No) switches the interval operations from strict to inclusive bounds.
These operations chain inside one Basic Operations Module, and each can use only the outputs of operations listed above it (see the StrataQuest workspaceLoading...). A mask from Compare is still one anonymous set of pixels; labelingLoading... turns it into separate objects. For one Otsu value computed from all fields of view, there is a separate engine, Otsu Threshold (global)Loading..., which can feed Total AreaLoading.... The NucleiLoading... engine's Automatic Background Threshold uses Otsu's method too.
Source: StrataQuest 8.1 Engines Reference, ch. 6 (pp. 18–19), ch. 6.1 (pp. 69–71), ch. 6.11 (pp. 310–348), ch. 26 (p. 450), ch. 33 (pp. 480–482); User Manual, Quick Actions (p. 154).