PixelFlux

PixelFlux is a Swift framework for GPU-based image filters using Metal. It allows applying real-time image effects like brightness adjustments and pass-through filtering. The project includes a demo iOS app to test the filters visually.

This is my first project working with Metal shaders and GPU programming. I built it to learn how to integrate Metal compute shaders into a Swift framework, structure reusable filter code, and connect it to an iOS app. While simple, it demonstrates the core concepts of GPU-based image processing.

Project Structure

• PixelFlux/ – The framework source code
  • Engine/ – Handles Metal setup, compute pipelines, and texture utilities
  • Filters/ – Swift classes wrapping Metal shaders (e.g., BrightnessFilter)
  • metal/ – Metal shader files (.metal) for GPU execution
  • Public/PixelFlux.swift – Public API to apply filters from Swift code
• PixelFluxDemo/ – iOS app demonstrating usage of the framework
• PixelFluxDemoTests/ and PixelFluxDemoUITests/ – Basic test targets

Usage

1. Build the PixelFlux framework in Xcode.
2. Add it to the demo app target under Frameworks, Libraries, and Embedded Content and select Embed & Sign.
3. Import the framework in your Swift code:

import PixelFlux

let filter = BrightnessFilter()
filter.brightness = 1.5
let outputTexture = filter.apply(inputTexture)

4. Run the demo app on a simulator or device to see the filters in action.

Learning Goals

• Understand how Metal shaders work and how to execute them from Swift
• Learn how to structure a Swift framework for reuse
• Explore basic GPU-based image processing techniques
• Gain experience linking frameworks to iOS apps

PixelFlux is a learning project, but it provides a foundation to expand with more advanced filters, multi-texture processing, or video effects in the future.