Core concepts

Screph keeps the confirmed description of a visual scene separate from temporary recognition results and execution. This distinction explains both the UI and the project format.

Source, Frame, ROI

Source: A selected region/window/monitor, camera, stream or set of files and folders from which Screph acquires visual data.
Frame: One concrete source image at a selected point in time.
ROI: Region of interest: the part of a frame used for markup or a CV operation.

Raw, Material, Display

Raw: Canonical pixels from the captured source or frame before presentation processing.
Material: The typed image or mask result owned by a particular canvas presentation. The pixel probe, histogram and line profile use the active presentation's material; if it is unavailable or not mapped to the canvas, there is no silent fallback to Raw.
Display: The final raster painted in a pane after display transforms and overlay composition. It may be composite and is not necessarily a valid measurement material.

Canonical project data

The canonical project is the saved source of truth: elements/features, annotations, typed relations, markup groups and related settings. Canonical changes use project history. Shared Undo/Redo commands route to the focused context; for example, measurement lines use separate local history and do not become project data.

Important: A CV candidate does not become a canonical element until the user or an authorized workflow explicitly applies it.

Containers and groups

Selection area: A geometry-only element with a visible rectangle. It automatically or manually collects fully contained elements/features into hierarchy; nesting routes an object to the smallest matching area. The area itself stores no image or crop.
Image frame: An ordinary element used as crop geometry when capturing frames into its Image Series. It is not a selection area.
Markup group: A named canonical aggregate referencing existing elements/features, with a role, optional sequence index, type and properties. A typed group can originate from confirmed candidate promotion, but the current Selector has no separate free-form visual CRUD editor for markup groups.

CV method, pipeline, candidate, evidence

CV method: One parameterized image-processing operation with an output.
Pipeline: A sequence or graph of CV operations. The Method Graph describes computation, not relationships between UI elements.
Candidate: A recognition proposal that can be previewed, accepted or rejected.
Evidence: Observations, confidence, geometry and diagnostics explaining where a candidate came from.

Three different graphs

Relation Graph

Typed relationships between project elements.

Method Graph

The computational graph of a CV pipeline.

Action Trace

A sequence of observed or executed automation actions.

Relation Graph distinguishes parent → child hierarchy, the system owner → feature projection, and editable user edges. A FeatureMatch is persisted separately under feature_matches and is not an edge in this graph.