FAQ
Frequently asked questions about Chromaform — device requirements, app architecture, file handling, and more.
What devices are supported?
Chromaform runs on iPad with A12 Bionic or later (iPad 8th generation, iPad Air 3rd generation, iPad mini 5th generation, or any iPad Pro) and iPhone 15 or later. For the best experience with large RAW files (50MP+), an iPad Pro with an M-series chip or an iPhone Pro with an A17+ chip and 8+ GB of RAM is recommended. The app requires iOS 16.0 or later.
How big is the app?
The base app is approximately 25 MB. This includes the Vulkan compute pipeline (384 pre-compiled SPIR-V shaders) and all built-in presets. Optional downloads are small:
| Component | Size | When downloaded |
|---|---|---|
| Film Pack (~80 LUTs) | ~2 MB | First time you open the Film Pack section |
| AI Denoise (OIDN shaders) | ~640 KB | First time you use AI Denoise |
| SAM 2.1 Tiny (Image Encoder) | ~64 MB | First time you use Smart Mask with point/box prompts |
| SAM 2.1 Tiny (Mask Decoder) | ~9.7 MB | |
| SAM 2.1 Tiny (Prompt Encoder) | ~2.0 MB |
What is the Vulkan pipeline?
Chromaform runs a 15-module GPU compute pipeline using the Vulkan graphics API, translated to Metal on iOS through MoltenVK. Each module is a Vulkan compute shader that processes the image on the GPU. This architecture enables algorithms that Apple's CoreImage framework cannot express — like Local Laplacian pyramids, frequency decomposition, deconvolution sharpening, and dark channel dehazing. See Vulkan Pipeline for the full module reference.
Why is there a "scene-referred" mode?
In scene-referred mode, the RAW file is decoded into linear light values (no tone mapping applied by the decoder). This gives the Film Curve module access to the full dynamic range of the sensor data, enabling proper highlight rolloff, shadow toe shaping, and hue-preserving tone mapping. In display-referred mode (the default), the image arrives already tone-mapped, so the film curve is skipped. Scene-referred mode is for photographers who want full control over the tone mapping process. See Film Curve for details.
How does tiled rendering work?
When an image exceeds 4000 pixels on either dimension, the pipeline splits it into overlapping tiles. Each tile includes 256 pixels of overlap on every side so that neighborhood-aware modules (llap, dehaze, eq) have sufficient context at tile borders. Tiles are rendered sequentially through the full 15-module pipeline, then composited into the final output image. A progress modal shows tile-by-tile status during export. This approach allows Chromaform to process 50+ megapixel images on devices with as little as 4 GB of RAM.
Where are masks stored?
Smart Masks and person segmentation masks are saved as PNG alpha channels in Documents/Masks/, keyed to the image filename. They persist across sessions and are included when you share or back up a project. You can view the mask files directly in the Files app.
Can I use custom LUTs?
Yes. Chromaform supports .cube 3D LUT files. Place them in Documents/LUTs/ via the Files app, AirDrop, or iTunes file sharing. They appear automatically in the Presets & LUTs panel. You can import LUTs from any source that produces .cube files — DaVinci Resolve, Photoshop, VSCO, or online LUT marketplaces.
Does Chromaform edit the original file?
No. All edits are non-destructive. The original image is never modified. Edit parameters are stored separately, and the final rendered output is written to Documents/Exports/ only when you explicitly export.
Can I edit photos from the Photos library?
Yes. During import, you can browse your Photos library and select images. Chromaform copies the full-resolution original into its own document storage. Edits are applied to this copy, not to the original in Photos.
Does it work on iPhone?
Yes. Chromaform runs on iPhone 15 and later. The full editing pipeline, including the Vulkan compute modules, works identically on iPhone. The interface adapts to the smaller screen, though the experience is optimized for iPad's larger display and Apple Pencil support.