Blurring an image

At a glance

Project structure

Source bundle/
├── vImageConvolution/
│   ├── vImageConvolutionApp.swift
│   ├── ContentView.swift
│   ├── ImageConvolver.swift
│   └── vImageConvolution.entitlements
├── Configuration/
│   └── SampleCode.xcconfig
└── vImage_Convolution.xcodeproj/
    ├── .xcodesamplecode.plist
    └── project.pbxproj

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 4 project/configuration file(s) and 4 source declaration(s).

Overall architecture

flowchart LR
    N1["vImageConvolutionApp"]
    N2["ContentView"]
    N3["Accelerate APIs"]
    N1 --> N2
    N2 --> N3

Reference code

vImageConvolution/vImageConvolutionApp.swift:10 — architecture anchor

@main
struct vImageConvolutionApp: App {
    // ...
}

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 Accelerate.

Ownership and state

classDiagram
    vImageConvolutionApp *-- ImageConvolver : imageConvolver
    ContentView o-- ImageConvolver : imageConvolver
    ImageConvolver o-- Mode : mode
    ImageConvolver o-- CGImage : outputImage

Ownership evidence

vImageConvolution/vImageConvolutionApp.swift:13 — stored dependency or nearest verified ownership anchor

@main
struct vImageConvolutionApp: App {
    // ...
    @StateObject private var imageConvolver = ImageConvolver(sourceImage: #imageLiteral(resourceName: "Landscape_4_Waterwheel.jpg"))
    // ...
}

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

vImageConvolution/vImageConvolutionApp.swift:11 — representative type boundary

struct vImageConvolutionApp: App {
    // ...
}

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

Access control

Reference code

vImageConvolution/vImageConvolutionApp.swift:13 — representative boundary

@main
struct vImageConvolutionApp: App {
    // ...
    @StateObject private var imageConvolver = ImageConvolver(sourceImage: #imageLiteral(resourceName: "Landscape_4_Waterwheel.jpg"))
    // ...
}

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: vImageConvolutionApp; View: ContentView.
• Protocols: no local protocol declaration in the scanned source.
• Methods: none, box, tent, generalConvolution, separableConvoution, multiKernelConvolution.
• Files: vImageConvolution/vImageConvolutionApp.swift, vImageConvolution/ContentView.swift, vImageConvolution/ImageConvolver.swift.

Architecture takeaways

• vImageConvolutionApp is the main source-visible entry or composition anchor for this sample.
• Framework work reaches SwiftUI, Accelerate, Cocoa 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