Darktable 5.6 has been released as the latest major update to the open-source RAW photo editor, bringing an optional AI subsystem, new masking and restoration tools, HEIF export support, a new color harmonizer module, user interface improvements, performance work, Lua updates, and numerous bug fixes.
This release follows the Darktable 5.4 series, and as with previous major updates, users should back up their configuration and library before upgrading, since libraries and settings updated by Darktable 5.6 are not compatible with version 5.4.
The main change in this release is the optional AI subsystem. It is disabled by default and must be enabled manually, requiring the -DUSE_AI=ON build option. When AI support is off, Darktable does not load ONNX Runtime libraries or perform any AI-related tasks.
When enabled, the AI subsystem allows Darktable to download and manage models from a configurable repository. Setup scripts are available for Linux and Windows to configure GPU acceleration for NVIDIA, AMD, and Intel hardware. On macOS and most Windows systems, GPU acceleration is included by default. Just to mention that a key feature of the AI subsystem is the new AI object mask tool in the darkroom mask manager.
Darktable 5.6 also adds a neural restore module to the lighttable and darkroom sidebar, supporting three AI-based tasks: raw denoise, image denoise, and upscaling. Default models include NIND UNet for denoise, RawNIND UtNet2 for raw denoise, and RealPLKSR 2x and 4x for super-resolution. Additional models such as NAFNet and BSRGAN can be installed manually from the model repository.
Beyond the AI capabilities, Darktable 5.6 features a color harmonizer module. It applies color harmony corrections in UCS color space, rotating hues toward structures such as complementary, split-complementary, triadic, and tetradic. The module also supports custom harmonies with user-defined anchor nodes, as well as controls for effect intensity, neutral color protection, and transition smoothing.
HEIF export support is another key addition. Users can select lossless or lossy compression, choose from supported color depths including 8-bit, 10-bit, and 12-bit, and use available color subsampling options.
The UI has received several updates as well. The crop module now displays the aspect ratio and dimensions in the crop area preview. A second darkroom window can pin images from the filmstrip, and users can switch between point and area color picker modes directly on the canvas using Ctrl-click.
Additionally, Darktable 5.6 features a condensed mode for panel controls, a 2-up scope displaying both waveform and vectorscope, and support for rendering and caching 6K or 8K previews in lighttable view. Darkroom preview resolution has increased from 720×450 to 1440×900, upgrading data for scopes and the color picker.
Performance improvements include faster OpenCL guided filtering with internal tiling, quicker processing in the blurs module for large radii, improved overlay module performance with a new OpenCL path, fewer unnecessary pixelpipe runs, and more efficient mask distortion handling.
Additional changes include Canon Automatic Lighting Optimizer support for CR3 images, PNG and vectorization support for external raster masks, a new image duplicate collection filter, improved AgX defaults, enhanced OpenCL preferences and device handling, and new HTJ2K compression options for EXR export when linked with OpenEXR 3.4 or later.
On the bug-fixies side, Darktable 5.6 resolves numerous issues, including mask positioning, color profile handling, shortcut behavior, OpenCL and CPU pixelpipe stability, tagging crashes, geolocation assignment errors, thumbnail sizing with display scaling, drawn mask editing, and several demosaicing problems.
For additional details, see the announcement. The full changelog is here. Darktable 5.6 is now available from the project’s official website and GitHub release page. Source archives, AppImage builds for x86_64 and aarch64 Linux, macOS packages for Intel and Apple Silicon, and Windows installers for x86_64 and Windows on ARM are provided.
