Canny locks outlines; Depth locks spatial feel and depth-of-field. They serve different scenarios.
Core difference
| Dimension | Canny | Depth |
|---|---|---|
| Extracts | Edge lines (black/white sketch) | Depth map (grayscale gradient) |
| Controls | Outline, shape, detail direction | Spatial feel, foreground/background, DoF |
| Best for | Architecture, product, line-heavy scenes | People, interiors, landscapes |
Four scenario picks
Architectural photographyPick Canny
Architecture has strong straight lines — Canny locks outlines reliably.
PortraitPick Depth
Depth preserves figure-vs-background space; Canny tends to lock skin texture too.
Interior sceneDepth preferred
Interiors care about depth layers — Depth controls them naturally.
Product shotCanny preferred
Precise product outline matters — Canny enforces shape strictly.
Stacking
Canny + Depth at 0.5–0.6 each gives "shape + space" dual lock. Common in precision commercial illustration.