Celenne Studio

A layered raster image editor for Windows (Electron + React + TypeScript), built around an editable, non-flattening PSD/PSB document model. macOS is architecturally supported (the platform layer is abstracted) but not yet packaged or tested.

Status: 0.3.0 — preview. The document model, PSD pipeline, rendering engine and most tools are implemented and tested. The full list of what is and isn't done is in docs/KNOWN_LIMITATIONS.md. Anything unfinished is marked Coming Soon in the UI. No button pretends to work.

ArtCraft / PhotoCraft developers: start with NOTES_FOR_ARTCRAFT.md. Licence: MIT OR Apache-2.0 (LICENSE); LibRaw stays LGPL 2.1.

Highlights

• PSD & PSB, layered. Open, edit and save back pixel, group, adjustment, fill, text, shape and smart-object layers. This includes masks, vector masks, clipping, 27 blend modes, layer effects, alpha channels, paths, guides, ICC profiles and 8/16/32-bit data. Unknown data blocks are preserved byte-for-byte. See docs/PSD_COMPATIBILITY.md.
• Text that moves freely with Photoshop. Celenne's own text engine (HarfBuzz shaping, Thai, vertical text, text on a path, warp) writes Photoshop's own text data. Photoshop opens Celenne's text as live text with no update prompt, laid out the same way. Celenne adds a composer of its own, optical margins and Fit Text to Frame. See docs/TYPOGRAPHY.md.
• Camera raw from every major brand. CR2, CR3, NEF, ARW, RAF, ORF, RW2, PEF, SRW and DNG open as 16-bit ProPhoto images, developed by Celenne (LibRaw unpacks proprietary formats).
• Never flattens silently. Flat formats are always saved as copies. Bit-depth reductions and mode conversions ask first. Unsupported features are reported per layer.
• Non-destructive editing: 16 adjustment-layer types, fill layers, smart objects with smart filters, editable layer styles and live shapes.
• Tiled engine: sparse 256 px tiles, copy-on-write history, mip pyramids and time-sliced display rendering. The viewport runs on WebGPU (WebGL 2 and Canvas 2D fallbacks) with a 3D-LUT for color-managed display, and WebGPU compute shaders composite the layers and run blur / sharpen / adjustment previews; files are always produced by the CPU code.
• Color management with LittleCMS (WebAssembly): assign/convert profiles, soft-proofing with a CMYK profile, and CMYK files converted on open.
• Tools:
  • Painting: brushes with pressure/tilt dynamics, retouching (clone, heal, patch, content-aware fill), erasers.
  • Selection: marquee, lasso, magnetic lasso, magic wand, quick selection, object/subject selection, and Select and Mask.
  • Other: transforms (free, distort, perspective), crop/perspective crop, gradients, type, pen/shape tools.
• Also: Liquify, 24 filters, actions/macros, customizable shortcuts, a dockable workspace, multi-document tabs, auto-save and crash recovery.
• Extensible:
  • Sandboxed plugins: filters, exporters, panels and AI tasks. See docs/PLUGINS.md.
  • A provider-neutral AI layer: local algorithms, your own HTTPS endpoint, or plugin models. See docs/AI_PROVIDERS.md.

Quick start

Requirements: Node.js 22+ (tested with Node 24) and Windows 10/11 x64.

Install dependencies:

npm install

Run the UI in a browser at http://localhost:5183 (fast iteration; files are opened with pickers and saved as downloads):

npm run dev

Run the desktop app against the dev server:

npm run dev:electron

Run the automated tests:

npm test

Build the Windows installer into release/:

npm run dist

Publish a release (signed manifest, auto-update, optional code signing) with npm run release; see docs/RELEASING.md. What the app sends over the network is listed in docs/PRIVACY.md.

More detail in docs/DEVELOPMENT.md.

Scripts

Script	Purpose
npm run dev / dev:electron	Vite dev server / Electron against it
npm run typecheck	tsc --noEmit over app, Electron, tests and scripts
npm run build	typecheck + renderer (Vite) + Electron main/preload (esbuild)
npm start	run the built app with Electron
npm run dist / dist:dir	NSIS installer / unpacked app (local builds, no auto-update)
npm run release -- --to …	release build: tests, code signing, signed update manifest, upload (RELEASING.md)
npm run release:keygen	create the Ed25519 release key (once)
npm run release:serve -- <dir>	local update server for testing
npm test	unit, PSD round-trip, compatibility suite, visual regression
npm run fixtures -- --refs	regenerate the 14 PSD fixtures and reference renders
npm run benchmark	engine benchmark → docs/BENCHMARK_RESULTS.md
npm run docs	regenerate docs/PSD_COMPATIBILITY.md and the sample plugin
npm run icon	regenerate build/icon.png

Repository layout

electron/        main process (app:// protocol, CSP, file access allowlist, atomic writes) + preload bridge
src/
  app/           editor, sessions, actions, menus, shortcuts, file operations, ops/*, autosave, platform/
  document/      document model, layer types & factory, cloning
  image-engine/  tiled rasters, blend modes, matrices, resampling, blur/morphology
  rendering/     compositor, render engine (display tiles), viewport renderers (WebGPU/WebGL2/Canvas2D)
  gpu/           WebGPU device, GPU tile compositor and preview filters (WGSL)
  psd/           container parser/serializer, ag-psd mapping, import/export, CMYK transcoding, matrix
  history/ commands/  command pattern, undo/redo, raster/layer commands
  selection/ vector/ typography/ color/ adjustments/ effects/ filters/ brush/ layers/ formats/
  ai/            AI provider abstraction (local / cloud / custom)
  plugins/       sandboxed plugin host + sample plugin
  tools/         all canvas tools
  ui/            React UI: menu bar, options bar, toolbar, canvas, panels, dialogs
tests/           engine, PSD round trip, compatibility suite, visual regression, fixtures
scripts/         build, fixtures, benchmark, docs, icon
docs/            architecture, API, compatibility, plugins, AI, limitations, benchmark
samples/plugins/ sample plugin package

Documentation

• Architecture
• PSD compatibility
• API (document model, commands, actions)
• Plugins
• AI providers
• Development & testing
• Benchmark and latest results
• Typography guide
• Known limitations

Licensing and trademarks

Celenne Studio is licensed under MIT OR Apache-2.0, at your option (LICENSE, LICENSE-MIT, LICENSE-APACHE). The name and icon are not licensed for other products.

Celenne Studio uses original UI styling and icons; it contains no Adobe assets. "Photoshop" is a trademark of Adobe Inc.; Celenne Studio is not affiliated with Adobe. Third-party components: ag-psd, LittleCMS (lcms-wasm), fflate, UTIF, fast-png, React, zustand, flexlayout-react and Electron (MIT-licensed), the JPEG decoder of jpeg-js / pdf.js (Apache License 2.0, vendored in src/formats/vendor/ for CMYK JPEG files), and LibRaw 0.22 for camera raw files (LGPL 2.1, built to WebAssembly as a separate, replaceable module; source, licence and build script in third_party/libraw/, also shipped with the app). Test fixtures from psd-tools are listed in tests/fixtures/third-party/README.md. The webgpu package (Dawn for Node, MIT) runs the GPU tests and benchmark headless; it is a development dependency and is not shipped.