Patchy is a free, open-source image editor for Windows, macOS, and Linux, built for accurate PSD and PSB editing and round trips with Adobe Photoshop. It supports editable text and vectors, masks, layer styles, Smart Objects and Smart Filters, legacy 8BF plug-ins, JavaScript scripting, and command-line automation.
The browser version is the same editor compiled to WebAssembly. It runs entirely on your machine and nothing you open or make is sent online. The desktop builds are the faster and more capable way to use Patchy: they are not limited to a browser tab's 4 GB of memory, and they add printing, scanner and camera import, and command-line automation.
Local AI agents can use the native MCP connector to draw, inspect previews, revise layers, and save editable files. In the desktop app, Help > Set up AI Control gives you a short text to paste into your AI assistant, which then configures itself. Agents can work in a separate workspace or connect to your open desktop app, where you can watch edits, choose Slow playback, pause to make changes yourself, and stop an operation. Desktop packages include an installable skill and JavaScript examples. See AI control setup.
Click a thumbnail for the full-size image.
Non-destructive adjustment layers with live preview and editable settings |
Layer styles with multiple effects, blending controls, and Photoshop-compatible presets |
Brush tip presets, import, management, spacing, angle, roundness, and texture controls |
Pressure-aware brush dynamics for size, opacity, flow, angle, scatter, and color |
Palette mode constrains painting and editing to a document color set |
Trace Image to Shapes turns any image into editable vector shape layers, with Illustrator-style presets and a live traced preview |
Warp Text with live preview: all 15 Photoshop warp styles on editable rich text |
Seamless tiling mode for game textures: paint on the canvas and strokes wrap live across every tile |
Smart Objects: Warp Transform bends them non-destructively, Edit Contents opens the embedded file in its own tab |
Photo textures in the Pattern Manager, with full-resolution preview, import, organization, and editing |
Editable native Smart Filters with one paintable shared mask and per-filter controls |
16-bit Camera Raw development with white balance, tone, color, demosaic, and denoise controls |
Tilt-Shift Blur with live on-image focus, angle, and transition controls |
Material layer styles backed by bundled CC0 wood, stone, metal, fabric, and ground textures |
Quick Mask turns a selection into a brush-editable red overlay, then back into marching ants |
Vector shape layers: gradient fills, pen paths, anchor editing, and the Paths panel |
Shape fills and strokes: solid, gradient, or pattern paint, dashes, and live corner radii |
SVG files open as editable shape layers: groups become folders, paths stay live vectors |
Script Manager running the bundled Breakout: the game plays on a real canvas, with live run status and one-click stop |
Scripts ask with real options dialogs; the same script runs unattended from the command line with the same defaults |
Affinity Photo, Designer, and Publisher files open as layered documents: groups, editable text, effects, and rasters come through |
Patchy is tested against Adobe Photoshop 2026 on a mixed PSD corpus. In the completed August 7, 2026 Testy run, Patchy had the strongest non-Adobe render result, Photoshop reopened all 64 Patchy saves, and all 312 text objects remained editable.
| Tested editor | Files opened | Perceptual render match | PSD saves rejected by Photoshop | Text still editable in resaved PSD |
|---|---|---|---|---|
Patchy 879a3a8 |
64 / 64 | 98.83% (n=63) | 0 / 64 | 312 / 312 |
| Photopea, web build | 63 / 64 | 97.13% (n=62) | 0 / 64 | 306 / 312 |
| Affinity 3.2.3.4646 | 61 / 64 | 88.30% (n=60) | 0 / 64 | 0 / 305 |
| GIMP 3.2.4 | 62 / 64 | 88.11% (n=61) | 0 / 64 | 0 / 312 |
| PhotoDemon 2026.01.0251 | 64 / 64 | 81.97% (n=63) | 0 / 64 | 0 / 312 |
| Krita 5.3.2.1 | 56 / 64 | 81.17% (n=56) | 9 / 64 | 187 / 205 |
The text column counts original text objects that Photoshop still recognizes as editable text after reopening the editor's PSD save. It does not identify whether conversion happened during import or export.
These are corpus-specific results, not universal product ratings. See the full results and methodology, including the image-free per-file run data, tested versions, native PSD data preservation, Photoshop round-trip rendering, and known limitations.
Latest release: 0.96 · September 17, 2026 · Release notes
Windows releases are code signed by Seth A. Robinson; the macOS app is signed and notarized (Robinson Technologies Corporation).
| Platform | Package | Download |
|---|---|---|
| Windows 10/11 (64-bit) | Installer | PatchyWindowsInstaller.exe (59 MB) |
| Windows 10/11 (64-bit) | Portable ZIP (no installer) | PatchyWindowsNoInstaller.zip (59 MB) |
| macOS 12+ (Apple Silicon) | DMG - drag to Applications | PatchyMacOS.dmg (64 MB) |
| Linux | Flatpak bundle | PatchyLinux.flatpak (31 MB) |
| Any modern browser | Nothing to install | rtsoft.com/patchy (slower and less capable) |
Linux one-line install (paste into a terminal; fetches the bundle and installs it, pulling the shared KDE runtime from Flathub automatically):
curl -L -o /tmp/PatchyLinux.flatpak https://rtsoft.com/files/PatchyLinux.flatpak && flatpak install -y /tmp/PatchyLinux.flatpakOptional: opening iPhone HEIC photos on Linux uses the shared Freedesktop codec extension, which bundle installs do not fetch on their own. Patchy will show this command if it is needed:
flatpak install -y flathub org.freedesktop.Platform.ffmpeg-full//24.08- Open and save layered PSD and PSB files with groups, masks, clipping masks, saved alpha and spot channels, text objects, Fill Opacity, the full Photoshop blend mode set, layer styles and more
- Common raster editing tools, including Brush with Flow and timed Airbrush buildup, Healing Brush, Spot Healing, Patch, Clone Stamp, Dodge, Burn, Sponge, Blur, Sharpen, Smudge, Eraser, selections, transforms, gradients, and shapes
- Vector tools: Pen paths, editable shape layers (Rectangle, Ellipse, Line, Polygon, Custom Shape) with solid, gradient, or pattern fills and strokes, vector masks, path selection and anchor editing, and a Paths panel with fill, stroke, and make-selection commands, all round-tripping through PSD files that open correctly in Photoshop
- Dynamic Vector Preview keeps native shapes and vector masks sharp when zoomed in, alongside pixel layers, masks, adjustments, and effects. Merge Layers can preserve editable vectors and keep bitmap runs separate, with options for merging within groups or making a merged copy
- Move tool layer selection: drag a rectangle to select overlapping layers, Shift-click to toggle individual layers, or right-click to choose among the layers under the pointer, with a selected-layer count in the status bar
- Trace Image to Shapes: converts a pixel layer (logo, scan, photo) into a group of editable shape layers, one per color, with Illustrator-style presets, color, grayscale, and black-and-white modes, abutting or overlapping shapes, noise removal, and a live preview; export the result as SVG
- Non-destructive adjustment layers (Levels, Curves, Hue/Saturation, Color Balance, Brightness/Contrast, Invert, Posterize, Threshold) with live preview, editable settings, native Photoshop PSD data, and .acv Curves preset import and export
- Smart Objects: place or convert layers to embedded or linked smart objects, edit or replace their contents, transform them non-destructively, and build editable native Smart Filter stacks (13 filter types) with paintable shared masks and per-filter blending
- Filter Gallery with 32 effects, live full-resolution preview, ordered effect stacks, favorites, and reusable Saved Looks, plus a manual Liquify workspace with warp, twirl, pucker, bloat, and freeze brushes
- Photoshop-compatible layer style, pattern, and gradient preset libraries, including .asl, .pat, and .grd import/export, 39 built-in styles, and 20 bundled CC0 photo textures
- Warp Transform tool and Warp Text with all 15 Photoshop warp styles and live preview
- Multiple document interface: tabbed documents that can float in their own windows, Photoshop-style Tile and Cascade arrangement, a Window menu that lists every open document, and layers that drag or duplicate between documents
- Rich text with per-run color, font, size, and style, plus a searchable font picker and Character controls for leading, tracking, and horizontal or vertical glyph scaling, editable on the selected text layer without entering text-editing mode
- Palettized (indexed color) editing mode for pixel art: paint constrained to a palette, quantize with optional dithering, built-in retro palettes (NES, C64, Game Boy, PICO-8, and more), palette files (.pal/.gpl/.hex/.act/.aco/.ase), and exact indexed PNG-8 and 2/4/8-bit BMP export. Layers, layer styles, and effects all keep working (Photoshop's indexed mode flattens and disables them)
- Named palette colors appear in the Palette panel, color picker, Info panel, and eyedropper readout. Rename swatches, preserve names through GPL, PSD, and indexed PNG round trips, and manage palettes through scripts
- Pixel-art and game-dev extras: seamless texture authoring (live tile preview window, in-canvas tiling mode, seam shifting), sprite sheet export/import, image sequence export/import (numbered files become layers and back), animated GIF import/export (frames become layers with their timings in the layer names, visible layers save back as a looping animation, and the layers panel's film button previews the animation in-app), and an Export Flat Image dialog with nearest-neighbor scaling (2x-8x), smooth resize, transparent-edge trimming, and background fill
- Reads and writes a wide range of formats: PSD/PSB, PNG, JPEG, TIFF, WebP, BMP, TGA, GIF, PCX, Amiga IFF/LBM, Windows icons and cursors (ICO/CUR), Aseprite files, JPEG XR (.jxr, on Windows), Proton SDK textures (.rttex), and SVG (opens as editable shape layers, exports with vectors preserved)
- Imports Affinity documents as layered files: the current .af format, Affinity 2 .afphoto/.afdesign/.afpub, and most Affinity 1.x-era files, bringing across rasters, groups, masks, clipping, blend modes, editable text layers, vector shapes, adjustment layers, layer effects, and placed images (which become embedded Smart Objects)
- Opens camera raw files (CR2/CR3/NEF/ARW/RAF/DNG and more) through a 16-bit develop dialog with a Natural rendering profile, ISO-based noise reduction, and per-photo settings saved beside the original, and HEIC/HEIF photos through platform codecs
- Opens HDR screenshots saved as JPEG XR (.jxr), the format NVIDIA's in-game capture uses, tone mapping the high dynamic range down to 8-bit so highlights keep their detail instead of clipping to white
- Photoshop-compatible document resolution, physical measurement units, rulers, image sizing, and printing
- Pen/stylus pressure and size dynamics, GUI scaling, scanner import (Windows and macOS), camera import (Windows), legacy .8bf plugins, and command line options
- JavaScript scripting: a built-in Script Manager (File > Scripts) with a folder tree over the bundled and user scripts, a code editor with live run status, a documented API covering documents, layers, text, selections, pixels, filters, form dialogs, file pickers, and batch processing, bundled examples ranging from CSV data merge, contact sheets, icon export, and versioned saves to glitch/duotone effects and playable Breakout and Pong (scripts can call other scripts), safe editing of bundled scripts (your saved copy overrides the original and can be reverted), and a --run-script command line flag with script arguments so external tools and AI agents can drive Patchy (add --headless to run with no display, on a server or in CI). See the scripting guide (also under Help inside the app)
- Local AI control through the bundled MCP connector: native pressure-aware brush strokes, reusable brush presets, editable vector shapes and paths, palette controls, image previews, and persistent document sessions. Help > Set up AI Control provides setup instructions and example prompts; see the AI control guide
- Cross-platform: Windows is the lead platform, with native macOS (Apple Silicon) and Linux (Flatpak) builds
- Built with C++ and Qt for a native desktop experience. No GPU used, should run on a potato
- Privacy: YES! Absolutely no telemetry, no tracking, no data collection (if update checks are enabled, it contacts GitHub only to check for a newer version). Settings live in a plain local file, and the installer doesn't screw with your file extension preferences
- Localized in English, German, Spanish, French, Italian, Japanese, and Chinese (Simplified and Traditional); the language follows your system or can be changed in File->Preferences
- Canvas Size preserves each layer's off-canvas pixels and masks when shrinking or enlarging the canvas. An optional "Also crop each actual layer to the canvas area" checkbox enables destructive cropping and starts unchecked every time the dialog opens
- Clipping masks above layer groups now use the group's combined transparency correctly
- Merge Visible to New Layer (Copy) preserves transparency in the merged copy
- Switching languages updates menus, panels, tool options, and the start screen consistently
-
The interface now supports German, Spanish, French, Italian, Japanese, and Simplified and Traditional Chinese alongside English. It follows your system language or your choice in File > Preferences. I had to add 20 mb to the filesize to include fonts to do this proper, but.. I think that's ok in the grand scheme of things.
Note: LLM translation is never perfect, so if you notice any glaring language errors in your native language please let me know or submit a pull request with your fixes on its language file. Oh, English now has it's own language file too. -
Starting a Move drag on a large document prepares the preview in the background, with a moving outline and an animated "Rendering preview..." indicator while it catches up. Repeated drags reuse more of the preview work, and rapid moves no longer pile up full renders
-
Fixed some weirdness with dragging down the Layers panel's eye column, the Character panel works without selecting text, double clicking the T icon for a text object now edits it instead of zooming in to it
-
New adjustment layers appear directly above the topmost selected layer, and include a default mask even if nothing is selected.
-
Paste centers copied selection pixels and clipboard images in the visible canvas area, keeping them inside the document when they fit. Edit > Paste in Place (Ctrl+Shift+V) restores copied selection pixels to their original coordinates, including across documents, with the same edge limits. Pastes now appear directly above the topmost selected layer.
-
The Move tool works better with stuff that is off the canvas, previously it hard to move them
-
Optimized working with large files, it's more responsible thanks to now allowing movement before preview data is generated and various improvements to how caching works
Build the dependency-light core and tests without the Qt app:
cmake --preset dev -DPATCHY_BUILD_APP=OFF
cmake --build --preset dev
ctest --preset devBuild the Qt desktop app:
cmake --preset qt-local
cmake --build --preset qt-localThe local Qt app preset writes patchy.exe under build/app.
Run the standard local test script:
powershell -ExecutionPolicy Bypass -File scripts/run-tests.ps1Install Qt 6.8.3 into .deps/Qt (for example pip install aqtinstall && aqt install-qt mac desktop 6.8.3 -m qtimageformats qtpdf -O .deps/Qt, or linux desktop 6.8.3 linux_gcc_64 on Linux), then build the matching preset. The qtpdf module is optional:
without it Patchy still exports PDF, it just cannot open one.
cmake --preset mac-release # or linux-release
cmake --build --preset mac-releasemacOS produces build/mac-release/Patchy.app; Linux produces
build/linux-release/patchy. packaging/macos/make-dmg.sh and
packaging/linux/make-flatpak.sh create the distributable artifacts. Both test suites
run offscreen on all three platforms (QT_QPA_PLATFORM=offscreen).
Create local Windows release artifacts:
scripts\release\build-release.batThe script configures and builds the release preset, signs build\release\patchy.exe, the installer helper executables, and the installer when the local signing environment is available, deploys the minimum Qt runtime needed by the current app, copies third-party notices, and creates:
build\package\PatchyWindowsNoInstaller.zip
build\package\PatchyWindowsInstaller.exe
The zip contains a top-level Patchy folder so it can be dragged anywhere and does not include installer-only helpers. The installer is a local per-user installer that installs to %LOCALAPPDATA%\Programs\Patchy, creates a Start Menu shortcut, offers a desktop shortcut, and registers an uninstall entry. latest_version.json is the update metadata file.
Patchy is not Photoshop-compatible across the full PSD surface yet, but a round-trip from/to Photoshop mostly works with RGB/RGBA 8-bit documents that use basic pixel layers, text objects, groups, masks, blend modes, layer styles, and the currently supported adjustment layers.
Important Photoshop features that are not supported yet, or are only partially supported:
- Editable Smart Filters cover 13 filter types with paintable shared masks and per-filter opacity and blend modes; unsupported imported filter types (including the Blur Gallery and Liquify smart filters) remain preview-locked and byte-preserved
- Full Photoshop adjustment-layer compatibility beyond Patchy's current adjustment support
- CMYK/Lab editing and export, editable spot separations and RGB component channels, multi-channel overlays, 16/32-bit editing, HDR/EXR, and full color-management parity (Patchy converts CMYK/Lab to RGB on open, but does not edit or save in those color modes)
- Layer comps, timeline/video/animation workflows, content-aware tools, and generative tools
- Photoshop's own automation surfaces: Actions (.atn), UXP/JSX panels, and scripts written for Photoshop (Patchy has its own JavaScript scripting and batch processing instead, see above)
- High-fidelity PSD/PSB edge cases, including layered PSB writing and byte-perfect preservation of every Photoshop-only metadata block
- Patchy is slower than Photoshop, especially on large documents and it doesn't support GPU acceleration at all. However, being CPU only helps with porting and stability so kind of a trade-off that makes sense, for now. That said, certain operations have been optimized for multicore - canvas compositing and image flattening are multithreaded, splitting large images (4 Mpx+) into strips rendered on all CPU cores.
Patchy opens Affinity documents read-only: the current .af format ("Affinity by Canva"), the Affinity 2 formats (.afphoto, .afdesign, .afpub), and most Affinity 1.x-era files. Raster layers (including 16-bit, float, CMYK, and Lab documents), groups, masks (raster and vector), clipping, blend modes, opacity, editable text with per-run styles, vector curves, parametric shapes (rectangles, ellipses, polygons, stars, triangles, diamonds, trapezoids, pies, segments, crescents, hearts, tears, arrows, double and square stars, cogs, clouds), compound-shape booleans, Designer symbols, artboards, layer effects, supported adjustment layers, and placed images (which become embedded Smart Objects) all import, verified against Affinity's own renders and a wild-file corpus that includes real Affinity 2 documents from all three apps. Vector fills and strokes keep their width, alignment, dash pattern, and miter limit, crop-to-shape containers come in as masked groups, and the Erase blend mode imports as an isolated group with an inverse-alpha mask, which is how PSD stores that construction natively. If a file can't be imported as layers, Patchy falls back to its embedded preview instead of failing the open, and an import notice explains what was skipped.
Affinity features that are not supported yet, or are only partially supported:
- Saving to Affinity formats (import only; save your edits as PSD)
- A few parametric shape kinds (callouts, spirals, QR codes, circle-rounded stars, and exotic arrow ends) import as named placeholders
- Adjustment layers beyond the eight kinds Patchy models, and live filters, import as named empty placeholders; Brightness/Contrast and Color Balance import approximately
- Affinity-only blend modes render through their closest Photoshop-compatible equivalent with a notice (Average matches exactly at half opacity; Negation, Reflect, Glow, and Pigment approximate; Contrast Negate falls back to Normal)
- Bevel/Emboss and glow effects are approximated; Gaussian blur layer effects bake into the layer pixels (they render correctly but are no longer live)
- Rotated or sheared frame text renders without its rotation (artistic text rotates correctly)
- Multi-page documents open the first page only
- Affinity 1.x-era files: embedded-document placement can land slightly off
Patchy is released under the MIT License. Third-party runtime notices are tracked in NOTICE-THIRD-PARTY.md.
Adobe and Photoshop are either registered trademarks or trademarks of Adobe in the United States and/or other countries. Patchy is an independent project and is not authorized, endorsed, or sponsored by Adobe. References to Photoshop and its file formats (PSD, Smart Objects, Smart Filters) are only there to describe compatibility.
This project was developed with significant assistance from AI tools. I mean, you can still blame me (Seth) for bugs, but I just wanted to mention it.
Note: All included textures/materials are real images taken by humans, not AI generated
AI has reached the point where you can use your favorite AI to add the missing feature you want.
Just give it the link to this repo and say "Add .tiff support" and in about 10 minutes it will be done and working on your computer. Amazing, right?
I mean, that's kind of the power of open source.
Whatever AI you use, tell it (or more likely, it is reading this right now) to read AGENTS.md before doing anything else. It contains the build and repository-wide rules, then routes feature work to the relevant document under docs/.
There are 1000+ regression and benchmarking tests. AGENTS.md links agents to the testing guide that explains how to select and run them.
If you have a bug fix or feature you think should be in this repo, please look at the actual code and fully TEST IT YOURSELF before submitting the PR. If you're using AI, use a good one (Fable+ class), we don't want barely working slop.
I probably don't want any major features coming from outside, as there are wrong and right ways to do things, some of it a bit subjective. Remember, you can always go crazy in your own fork, have some fun!
Don't trust AI to create and submit PRs with no oversight, I'll delete ones that have too much AI smell. Smell human. This is starting to sound weird but you know what I mean.
Also, note that certain features are crippled or not included due to Adobe patents. For example, our "quick select" tool doesn't update in realtime, you have to finish the stroke. We can revisit this around 2030 when the patents expire...
Created by Seth A. Robinson - Homepage | Blog | Twitter | Bluesky | Mastodon
Code contributions from Michael Capogna
Photo "akiko_cycling_okinawa" (seen in the screenshots) by Seth A. Robinson