# Steep

> Steep is a free, open-source raw photo editor for Windows, macOS and Linux. Built on RawTherapee, with film looks, AI masks and an MCP server for AI agents.

- Page: https://www.repuccico.com/steep
- Source code: https://github.com/cheetohsum/Steep
- Build from source (recommended for now): https://github.com/cheetohsum/Steep#building-from-source
- Nightly builds (can be behind the source): https://github.com/cheetohsum/Steep/releases/tag/nightly-github-actions
- Licence: GPL-3.0 (free and open source)
- Based on: RawTherapee (https://rawtherapee.com)

AI masks · Film Lab · Auto edit · Double exposure · AI denoise · Remove object · Colour wheels · MCP server for agents · AI runs on your computer · Free and open source

Steep changes most days. For now the best way to get it is to build it from source.
The steps for Windows, macOS and Linux are in the README on GitHub.

## Before and after

Each pair is one photograph rendered twice by Steep.

- The edit: https://www.repuccico.com/steep/ba/edit-before.webp and https://www.repuccico.com/steep/ba/edit-after.webp
- Film Lab: Desert chrome: https://www.repuccico.com/steep/ba/film-desert-chrome-before.webp and https://www.repuccico.com/steep/ba/film-desert-chrome-after.webp
- Film Lab: Cinematic 500T: https://www.repuccico.com/steep/ba/film-cinematic-500t-before.webp and https://www.repuccico.com/steep/ba/film-cinematic-500t-after.webp
- Film Lab: Sovereign: https://www.repuccico.com/steep/ba/film-sovereign-before.webp and https://www.repuccico.com/steep/ba/film-sovereign-after.webp
- Colour grade: https://www.repuccico.com/steep/ba/color-grade-before.webp and https://www.repuccico.com/steep/ba/color-grade-after.webp
- Tilt-shift: https://www.repuccico.com/steep/ba/tilt-shift-before.webp and https://www.repuccico.com/steep/ba/tilt-shift-after.webp

## Features

- Edit, by hand and with four Auto Edit versions
- Film Lab
- Colour grade
- AI masks
- Double exposure
- AI denoise
- Tilt-shift
- Library: stars, filters, albums with previews
- Themes and an interface you can resize and rearrange
- MCP server for AI agents
- Point colour
- Glow and halation
- Lens corrections
- Watermarks
- Export queue
- Filename templates

## Screenshots

- Steep's editor: a filmstrip across the top, the photo in the middle, and exposure sliders and a tone curve on the right: https://www.repuccico.com/steep/editor.webp
- Steep's library: a grid of photo thumbnails with star ratings and flags, and folders down the left: https://www.repuccico.com/steep/library.webp
- Steep's Edit mode with the groups closed: Exposure and tone, Black and white, Color, Detail, Effects and Camera, each with a strip of previews: https://www.repuccico.com/steep/groups.webp
- Steep's Presets mode: preset cards in groups, each a small preview of the open photo: https://www.repuccico.com/steep/presets.webp
- Steep's Film Lab with the list of film stocks open: Heritage gold, Porcelain 400, Vivid chrome, Desert chrome, Cinematic 500T and others: https://www.repuccico.com/steep/film-lab.webp
- Steep's Color group: temperature, tint, vibrance and saturation sliders above three colour wheels for shadows, mids and highs: https://www.repuccico.com/steep/color.webp
- Steep's Mask mode with the AI mask list open: Subject, Person, Sky, Vegetation, Building, Vehicle, Animal, Background, Near and Far: https://www.repuccico.com/steep/masks.webp

## For AI agents (MCP server)

Steep has an MCP server built in. Claude, or any agent that speaks MCP, can open a photo, read its settings and change them.
Open MCP Server in the app to see the address.

- `get_image_info`: Image metadata and EXIF
- `get_params / set_params`: Read and write the edit settings
- `set_tool_enabled`: Turn one tool on or off
- `list_tools`: Every tool and its state
- `adjust_exposure`: Quick exposure change
- `adjust_white_balance`: Quick white balance change
- `load_profile / save_profile`: Read and write PP3 profiles
- `list_volumes`: Connected drives
- `get_mount_events`: When drives come and go
- `scan_photos`: Read EXIF across a folder
- `import_photos`: Import and file photos by date

Client configuration (replace PORT with the one the app shows):

```json
{
  "mcpServers": {
    "steep": { "type": "http", "url": "http://localhost:PORT/mcp" }
  }
}
```

## Nightly builds

Ready-made builds, if you'd rather not build it. They can be behind the source.

- Windows x86_64: [Installer](https://github.com/cheetohsum/Steep/releases/download/nightly-github-actions/Steep_dev_win64_x86_64_release.exe), [ZIP](https://github.com/cheetohsum/Steep/releases/download/nightly-github-actions/Steep_dev_win64_x86_64_release.zip)
- Windows ARM64: [Installer](https://github.com/cheetohsum/Steep/releases/download/nightly-github-actions/Steep_dev_win64_arm64_release.exe), [ZIP](https://github.com/cheetohsum/Steep/releases/download/nightly-github-actions/Steep_dev_win64_arm64_release.zip)
- macOS Apple Silicon: [DMG](https://github.com/cheetohsum/Steep/releases/download/nightly-github-actions/Steep_dev_macOS_arm64_Release.zip)
- macOS Intel: [DMG](https://github.com/cheetohsum/Steep/releases/download/nightly-github-actions/Steep_dev_macOS_x86_64_Release.zip)
- Linux x86_64: [AppImage](https://github.com/cheetohsum/Steep/releases/download/nightly-github-actions/Steep_dev_x86_64_release.AppImage)
- Linux ARM64: [AppImage](https://github.com/cheetohsum/Steep/releases/download/nightly-github-actions/Steep_dev_arm64_release.AppImage)

## Questions

**Is Steep free?** Yes. Steep is free and open source under the GNU General Public License v3, the same licence as RawTherapee.

**How do I get Steep?** For now the best way is to build it from source; the steps for Windows, macOS and Linux are in the README on GitHub. Nightly builds are on the GitHub releases page too, but they can be behind the source.

**What does Steep run on?** Windows (x86_64 and ARM64), macOS (Apple Silicon and Intel) and Linux (x86_64 and ARM64, as an AppImage).

**How is Steep different from RawTherapee?** Steep keeps RawTherapee's processing engine and changes the editor around it: four modes (Presets, Edit, Crop, Mask), film looks, colour wheels, AI masks, object removal, albums, and a built-in MCP server. Nothing from RawTherapee was removed.

**Which cameras does Steep support?** The same raw formats as RawTherapee. JPEG and TIFF files open too.

**Do the AI tools send my photos anywhere?** No. The models run inside the app, on your own computer, through ONNX Runtime. On Windows they use the graphics card through DirectML when it is there.

**Which AI models does Steep use?** Six, each open source under a licence that can ship inside a GPL program.
- Masks by kind: sky, person, building, plants: A segmentation network trained on ADE20K's 150 classes, from MIT CSAIL (BSD-3-Clause). The 8 MB MobileNetV2 version ships with Steep. A 254 MB HRNetV2-W48 version is more accurate and makes finer masks.
- Subject masks: BiRefNet (MIT), with a Swin-L backbone, working at 1024 by 1024. It replaced U²-Net, which worked at 320 by 320 and lost hair, fur and thin edges. It is about 900 MB and wants a graphics card.
- Click to select: SAM 2, Meta's Segment Anything Model 2 (Apache 2.0). Click a thing and it finds its outline.
- Masks by distance: Depth Anything V2 Small (Apache 2.0) estimates how far away each part of the photo is, for the Near and Far masks and for lens blur.
- Remove object: LaMa (Apache 2.0), the big-lama inpainting model from Suvorov and others, 2022. About 200 MB, so the app downloads it the first time you ask for it.
- AI denoise: The ShadowWeightedL1 model from RawRefinery by Ryan Mueller (MIT), 19 MB, bundled. If RawRefinery is already installed, Steep uses its copy.

**Can an AI agent use Steep?** Yes. Steep has a built-in MCP (Model Context Protocol) server over HTTP. An agent such as Claude can read a photo's metadata, read and write its edit settings, turn tools on and off, and import photos.