DP44/enriched-qwen3-coder-next/Common/DTS.Common/Interface/RegionOfInterest.md

---
source_files:
  - Common/DTS.Common/Interface/RegionOfInterest/IRegionOfInterest.cs
generated_at: "2026-04-16T02:57:51.269981+00:00"
model: "Qwen/Qwen3-Coder-Next-FP8"
schema_version: 1
sha256: "79c0c78dabaa068e"
---

# RegionOfInterest

## 1. Purpose  
This module defines the `IRegionOfInterest` interface, which represents a configurable time- or sample-based region of interest (ROI) for signal processing or data analysis within the DTS system. It enables consumers to specify a temporal span (`Start`, `End`), associate it with specific channels (via `ChannelNames` and `ChannelIds`), and control its activation state (`IsEnabled`) and default status (`IsDefault`). As it implements `INotifyPropertyChanged`, it supports data binding and reactive UI updates when its properties change. The interface is designed to be implemented by concrete ROI types used throughout the application for segmenting, filtering, or analyzing time-series data.

## 2. Public Interface  

- **`string Suffix { get; set; }`**  
  Gets or sets a user-defined suffix appended to the ROI’s display name (e.g., for labeling or grouping). Changing this property raises `PropertyChanged`.

- **`double Start { get; set; }`**  
  Gets or sets the inclusive start boundary of the ROI, expressed in the same unit as the underlying data (e.g., seconds, samples). Changing this property raises `PropertyChanged`.

- **`double End { get; set; }`**  
  Gets or sets the exclusive end boundary of the ROI, expressed in the same unit as `Start`. Changing this property raises `PropertyChanged`.

- **`bool IsEnabled { get; set; }`**  
  Gets or sets a flag indicating whether the ROI is active and should be considered in processing. Changing this property raises `PropertyChanged`.

- **`bool IsDefault { get; set; }`**  
  Gets or sets a flag indicating whether this ROI is the default ROI (e.g., applied when no other ROI is selected). Changing this property raises `PropertyChanged`.

- **`string[] ChannelNames { get; set; }`**  
  Gets or sets the human-readable names of channels associated with this ROI. Changing this property raises `PropertyChanged`.  
  *Note:* Assignment replaces the entire array; partial updates require reassignment.

- **`long[] ChannelIds { get; set; }`**  
  Gets or sets the unique identifiers (e.g., hardware or logical channel IDs) corresponding to `ChannelNames`. The arrays `ChannelNames` and `ChannelIds` are expected to be parallel (i.e., `ChannelIds[i]` corresponds to `ChannelNames[i]`). Changing this property raises `PropertyChanged`.

- **`void SetChannelNamesNoNotify(string[] names)`**  
  Sets `ChannelNames` to `names` *without* raising `PropertyChanged` events. Useful for batch initialization or bulk updates where intermediate state changes should not trigger UI updates. The caller must ensure `names` is not null and matches the length of `ChannelIds` if `ChannelIds` has been previously set.

- **`void SetChannelIdsNoNotify(long[] ids)`**  
  Sets `ChannelIds` to `ids` *without* raising `PropertyChanged` events. Must be used in conjunction with `SetChannelNamesNoNotify` for consistent channel metadata updates. The caller must ensure `ids` is not null and matches the length of `ChannelNames` if `ChannelNames` has been previously set.

- **`void ResetSuffix()`**  
  Resets `Suffix` to its default value (implementation-defined; typically `string.Empty`). Behavior implies a property change notification *should* be raised, though the interface does not explicitly guarantee this—consumers should verify via testing or implementation.

## 3. Invariants  

- `Start` and `End` must satisfy `Start <= End` for valid ROI definitions (though enforcement is not specified in the interface and may be deferred to implementations or consumers).  
- `ChannelNames` and `ChannelIds` must have identical array lengths when both are non-null.  
- `ChannelNames` and `ChannelIds` are expected to be parallel arrays: index `i` in `ChannelNames` corresponds to index `i` in `ChannelIds`.  
- `IsDefault` should be `true` for at most one ROI instance within a given collection (e.g., a list of ROIs), though this constraint is not enforced by the interface itself.  
- Implementations must raise `PropertyChanged` for all property setters *except* when using `SetChannelNamesNoNotify` or `SetChannelIdsNoNotify`.  
- `ResetSuffix()` is expected to restore `Suffix` to a canonical default (e.g., `""`), but the exact behavior is implementation-specific.

## 4. Dependencies  

- **Depends on:**  
  - `System.ComponentModel` (for `INotifyPropertyChanged`).  
  - `System` (implicit via `string`, `double`, `bool`, `long`, `void`, `string[]`, `long[]`).  

- **Depended on by (inferred):**  
  - Any component that manages or renders ROIs (e.g., ROI editors, analysis pipelines, UI view models).  
  - Likely consumed by concrete types in `DTS.Common.Interface.RegionOfInterest.*` or downstream modules (e.g., `DTS.Processing.*`).  
  - Data binding frameworks (e.g., WPF, MAUI) via `INotifyPropertyChanged`.

## 5. Gotchas  

- **No validation in interface:** The interface does not enforce `Start <= End`, non-null arrays, or matching lengths of `ChannelNames` and `ChannelIds`. Implementations must handle these constraints.  
- **`SetChannelNamesNoNotify`/`SetChannelIdsNoNotify` are low-level:** Misuse (e.g., setting only one array) can leave the ROI in an inconsistent state. Callers must update both arrays atomically if needed.  
- **`ResetSuffix()` behavior is unspecified:** The interface does not define what the "default" suffix is or whether `PropertyChanged` is raised. Implementations may vary.  
- **No explicit ordering guarantee:** The order of channels in `ChannelNames`/`ChannelIds` is significant but not validated; consumers must preserve ordering semantics.  
- **No thread-safety guarantees:** As with most `INotifyPropertyChanged` implementations, this interface does not imply thread-safe property updates.  
- **None identified from source alone.**