README.md

---
license: bsd-3-clause
library_name: coreml
pipeline_tag: image-to-image
tags:
  - coreml
  - core-ml
  - ios
  - macos
  - apple
  - on-device
  - super-resolution
  - upscaling
  - gan
  - arxiv:2107.10833
---

# Real-ESRGAN 4x — Core ML

*Super Resolution, 2021*

Real-world blind super-resolution. 4× upscale from any input. Handles noise, blur, and JPEG artifacts. 512×512 input → 2048×2048 output.

<p><img src="https://huggingface.co/mlboydaisuke/Real-ESRGAN-x4-CoreML/resolve/main/media/8c997df784.png" alt="Real-ESRGAN 4x demo" width="49%"> <img src="https://huggingface.co/mlboydaisuke/Real-ESRGAN-x4-CoreML/resolve/main/media/166187d198.jpg" alt="Real-ESRGAN 4x demo" width="49%"></p>

Core ML conversion of [xinntao/Real-ESRGAN](https://github.com/xinntao/Real-ESRGAN) for on-device inference on iPhone, iPad and Mac. Converted with `coremltools`; the packages are stateless, so all sequencing and buffering lives in your Swift code.

| | |
|---|---|
| Task | image to image |
| Upstream | [xinntao/Real-ESRGAN](https://github.com/xinntao/Real-ESRGAN) |
| Packages | 1 |
| Download size | 59 MB |
| Minimum iOS | 17.0 |
| Peak RAM | ~500 MB |

## Files

| File | Size | Compute units | SHA-256 |
|---|---:|---|---|
| `RealESRGAN_x4.mlpackage.zip` | 59 MB | `all` | `5fd9d7ea7e6187ff…` |
| **Total** | **59 MB** | | |

`compute_units` is not a suggestion -- it is the configuration the conversion was verified against. Moving a package to a different compute unit can silently change the numerics (FP16 attention overflow) or crash on the GPU.

## Download

```bash
hf download mlboydaisuke/coreml-zoo --include "realesrgan/*" --local-dir ./realesrgan
unzip './realesrgan/realesrgan/*.zip' -d ./realesrgan
```

## Use in Swift

```swift
import CoreML

let config = MLModelConfiguration()
config.computeUnits = .all   // as converted — see the table above

// Unzip the .mlpackage, drop it into your Xcode target and Xcode compiles it
// at build time:
let model = try RealESRGAN_x4(configuration: config)

// ...or compile a downloaded .mlpackage at runtime:
let compiled = try await MLModel.compileModel(at: mlpackageURL)
let model = try MLModel(contentsOf: compiled, configuration: config)
```

## Demo

- **Models Zoo** — this model is downloadable and runnable inside the [Models Zoo app](https://apps.apple.com/app/id6762083207) on the App Store, no build required.

## Conversion

- Pitfalls hit during conversion (FP16 overflow, ANE buffer limits, stride handling): [`docs/coreml_conversion_notes.md`](https://github.com/john-rocky/CoreML-Models/blob/master/docs/coreml_conversion_notes.md)
- Model index: [CoreML-Models](https://github.com/john-rocky/CoreML-Models)

## License

The conversion inherits the upstream license: **BSD-3-Clause**.

## Credits

- Upstream authors: [xinntao/Real-ESRGAN](https://github.com/xinntao/Real-ESRGAN), 2021
- Core ML conversion: john-rocky (Daisuke Majima)