Processing Apple Immersive Video with foveation

At a glance

Project structure

Source bundle/
├── ImmersiveMediaSupport-Foveation/
│   ├── ImmersiveMediaSupport-Foveation/
│   │   ├── FoveateAIV.swift
│   │   ├── AIMEProcessor.swift
│   │   ├── FoveationEngine.swift
│   │   ├── MetalProcessor.swift
│   │   ├── VideoProcessor.swift
│   │   ├── UVSample.metal
│   │   ├── Types/
│   │   │   ├── FoveationConfig.swift
│   │   │   └── RuntimeError.swift
│   │   └── AVVideoCodecTypeExtension.swift
│   └── ImmersiveMediaSupport-Foveation.xcodeproj/
│       ├── .xcodesamplecode.plist
│       └── project.pbxproj
└── Configuration/
    └── SampleCode.xcconfig

Structure observations

• Architecturally prominent files are ranked from entry points and role-named declarations; resource-only paths are omitted.
• Primary languages: Metal, Swift.
• The verified tree contains 3 project/configuration file(s) and 9 source declaration(s).

Overall architecture

flowchart LR
    N1["FoveateAIV"]
    N2["FoveationEngine"]
    N3["ImmersiveMediaSupport APIs"]
    N1 --> N2
    N2 --> N3

Reference code

ImmersiveMediaSupport-Foveation/ImmersiveMediaSupport-Foveation/FoveateAIV.swift:12 — architecture anchor

@main
struct FoveateAIV: AsyncParsableCommand {
    // ...
}

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 Immersive Media Support.

Ownership and state

classDiagram
    FoveateAIV *-- CommandConfiguration : configuration
    FoveateAIV *-- String : inputVideoFile
    FoveateAIV *-- String : inputAIMEFile
    FoveateAIV *-- String : outputDirectory

Ownership evidence

ImmersiveMediaSupport-Foveation/ImmersiveMediaSupport-Foveation/FoveateAIV.swift:14 — stored dependency or nearest verified ownership anchor

    static let configuration = CommandConfiguration(
        // ...
    )

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

ImmersiveMediaSupport-Foveation/ImmersiveMediaSupport-Foveation/AIMEProcessor.swift:12 — representative type boundary

final class AIMEProcessor {
    // ...
}

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

Access control

Reference code

ImmersiveMediaSupport-Foveation/ImmersiveMediaSupport-Foveation/AIMEProcessor.swift:14 — representative boundary

    private let foveationConfig: FoveationConfig

    private let inputAIMEURL: URL
    private let outputAIMEURL: URL
    private let venueDescriptor: VenueDescriptor

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: Engine: FoveationEngine; Processor: AIMEProcessor, MetalProcessor, VideoProcessor.
• Protocols: no local protocol declaration in the scanned source.
• Methods: run, validateParameters, validateInputs, validateOutputs, process, foveateMesh, generateMesh, createBuffers.
• Files: ImmersiveMediaSupport-Foveation/ImmersiveMediaSupport-Foveation/FoveateAIV.swift, ImmersiveMediaSupport-Foveation/ImmersiveMediaSupport-Foveation/AIMEProcessor.swift, ImmersiveMediaSupport-Foveation/ImmersiveMediaSupport-Foveation/FoveationEngine.swift, ImmersiveMediaSupport-Foveation/ImmersiveMediaSupport-Foveation/MetalProcessor.swift, ImmersiveMediaSupport-Foveation/ImmersiveMediaSupport-Foveation/VideoProcessor.swift, ImmersiveMediaSupport-Foveation/ImmersiveMediaSupport-Foveation/Types/FoveationConfig.swift.

Architecture takeaways

• FoveateAIV is the main source-visible entry or composition anchor for this sample.
• Framework work reaches AVFoundation, VideoToolbox, ArgumentParser, ImmersiveMediaSupport 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