Counting human body action repetitions in a live video feed

At a glance

Project structure

Source bundle/
├── CountMyActions/
│   ├── App/
│   │   ├── MyApp.swift
│   │   └── ContentView.swift
│   ├── Model/
│   │   └── ViewModel.swift
│   ├── Views/
│   │   ├── CameraView.swift
│   │   ├── CameraWithPosesAndOverlaysView.swift
│   │   ├── OverlayView.swift
│   │   └── PosesView.swift
│   ├── CountingPipeline/
│   │   └── ActionCounter.swift
│   └── DrawPose/
│       ├── Connection.swift
│       ├── Joint.swift
│       └── Pose.swift
└── Configuration/
    └── SampleCode.xcconfig

Structure observations

• Architecturally prominent files are ranked from entry points and role-named declarations; resource-only paths are omitted.
• Primary languages: Swift.
• The verified tree contains 5 project/configuration file(s) and 9 source declaration(s).

Overall architecture

flowchart LR
    N1["MyApp"]
    N2["ContentView"]
    N3["ViewModel"]
    N4["CreateMLComponents APIs"]
    N1 --> N2
    N2 --> N3
    N3 --> N4

Reference code

CountMyActions/App/MyApp.swift:10 — architecture anchor

@main
struct MyApp: App {
    var body: some Scene {
        WindowGroup {
            ContentView()
        }
    }
}

Interpretation

The arrows summarize the source-visible entry, role-named types or folders, and framework direction; when nodes come from structural folders, the sequence is a high-level interpretation rather than proof that every adjacent node calls the next. Ownership is claimed only where the next section cites a stored property or assignment. The diagram is intentionally limited to the dominant path into Create ML Components.

Ownership and state

classDiagram
    ViewModel o-- Pose : liveCameraImageAndPoses
    ViewModel *-- Float : uiCount
    ViewModel o-- Task : displayCameraTask
    ViewModel o-- Task : predictionTask

Ownership evidence

CountMyActions/Model/ViewModel.swift:15 — stored dependency or nearest verified ownership anchor

    @Published var liveCameraImageAndPoses: (image: CGImage, poses: [Pose])?

    /// The user-visible value of the repetition count.
    var uiCount: Float = 0.0

    private var displayCameraTask: Task<Void, Error>?

Composition arrows indicate a source-visible construction expression or locally owned value state; aggregation means the owner stores or receives a dependency without proving exclusive lifetime ownership.

Class and protocol design

CountMyActions/App/MyApp.swift:11 — representative type boundary

struct MyApp: App {
    var body: some Scene {
        WindowGroup {
            ContentView()
        }
    }
}

No local protocol conformance is claimed as protocol-oriented design; external framework conformances are listed only as dependencies.

Access control

Reference code

CountMyActions/DrawPose/Connection.swift:27 — representative boundary

    struct Connection: Equatable {
        // ...
        private let point1: CGPoint
        // ...
    }

Swift declarations without a modifier are internal; explicit private, fileprivate, private(set), public, or open entries above are interpreted by language semantics. Objective-C/C samples instead rely on header and implementation boundaries, which are not equivalent to Swift lexical privacy.

Logic ownership and placement

Design patterns

Naming conventions

• Types: App: MyApp; View: CameraView, CameraWithPosesAndOverlaysView, ContentView, OverlayView, PosesView; ViewModel: ViewModel.
• Protocols: no local protocol declaration in the scanned source.
• Methods: initialize, onCameraButtonTapped, toggleCameraSelection, startVideoProcessingPipeline, displayPoseInCamera, predictCount, display, bubbleBackground.
• Files: CountMyActions/App/MyApp.swift, CountMyActions/Model/ViewModel.swift, CountMyActions/Views/CameraView.swift, CountMyActions/Views/CameraWithPosesAndOverlaysView.swift, CountMyActions/Views/OverlayView.swift, CountMyActions/Views/PosesView.swift.

Architecture takeaways

• MyApp is the main source-visible entry or composition anchor for this sample.
• Framework work reaches SwiftUI, CreateMLComponents, AsyncAlgorithms through a deliberately small high-level chain; the detailed API graph remains inside the cited implementation files.
• Stored-property evidence identifies lifecycle collaboration; it does not by itself prove exclusive object ownership.
• Access-control conclusions separate verified language visibility from the likely design rationale.
• The source does not justify labeling the design protocol-oriented.

Source map

• Official Apple documentation