photocraft/docs/file-format-parity.md

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File-format parity

Last reviewed: 2026-10-10 · Last updated: 2026-10-12 · Change: minor (Save keeps a JPEG's quality and a WebP's lossy/lossless encoding) · Target: Adobe Photoshop 2026

Every format Photoshop 2026 (27.11.0) reads or writes, with PhotoCraft's support, fidelity and tests. Photoshop's list comes from its Info.plist CFBundleDocumentTypes, the PiPL read/write flags of Contents/PlugIns/Required/File Formats, and format names in the main binary (Open/Save As behaviour from Adobe's documentation where the bundle doesn't say). Ours comes from crates/codecs/src/format.rs (capability table), crates/io/src/lib.rs (import/export dispatch), crates/psd, crates/raw, crates/heif, crates/affinity. More detail on our side: raster formats, PSD/PSB, OpenRaster, Paint.NET.

Summary. By count, 13 of Photoshop's 31 formats are fully supported in the directions Photoshop supports them, 4 partially (48%, measured). Weighted by use (PSD/PSB 40%, JPEG 15%, PNG 15%, TIFF 10%, camera raw 8%, WebP/AVIF/ HEIF/JXL 6%, PDF 3%, everything else 3%), presence is ~80% and ready-for-real-work ~60%: PSD is broad but not yet reliable against Photoshop (gap G1), and Photoshop PDF, AVIF read and JPEG XL are missing (gap G10). Remaining: 300–500 h including PSD fidelity.

Photoshop's formats

Format Photoshop PhotoCraft read PhotoCraft write Fidelity and tests
PSD R/W yes yes 1/8/16/32-bit; Bitmap, Gray, Indexed, RGB, CMYK, Multichannel, Lab, Duotone; layers, groups, masks, vector masks, adjustment and fill layers, effects, text, shapes, smart objects (SoLd/lnk2), smart filters (14 mapped, rest verbatim), slices, comps, Advanced Blending. Oracle floors: Photoshop-authored 133/256, io 146/170, psd-tools 236/309; round trip ≥ 169/170, 308/309, 258/256. Known failures: #1281, #2469, #2465 (#2374, text layers, closed 2026-10-10)
PSB R/W yes yes Auto-switches above 2 GB (REL-212-2); 4–5 GB fixtures generated (FILE-216-2); > 4 GB fails on Windows (#375)
Cloud PSD (.psdc) R/W no no Out of scope (Adobe cloud)
TIFF R/W yes yes 8/16/32f, Gray/RGB/CMYK, BigTIFF, every IFD, banded parallel decode; layered TIFF both byte orders (FILE-215-7: extra alpha channels not written)
JPEG R/W yes yes 8-bit Gray/RGB/CMYK, ICC/EXIF/XMP; Save keeps the opened file's quality (estimated from its quantisation tables, #2399); no JPEG Options dialog (quality 0–12, baseline/progressive) (FILE-215-19)
PNG R/W yes yes 8/16-bit, ICC/text; APNG first frame only; alpha channels on open (#2225)
GIF R/W yes yes File › Open keeps the first frame; New Video Layer from File and Video Frames to Layers take every frame, with the timeline rate from the delays (#572). Per-frame delays and keeping the frames in .pcraft are not done
BMP R/W yes yes 8-bit
WebP R/W yes yes Lossless and our own lossy VP8 encoder; ICC/EXIF/XMP; Save keeps an opened file lossy (at its quality) or lossless (#2399)
AVIF R/W no (#463) optional feature, off by default
JPEG XL R/W inside DNG only no
HEIF/HEIC R/W(HEIF) yes (pure-Rust heic-rs, heif feature, on in releases) no 8/16-bit
OpenEXR R/W yes yes f16/f32; deep EXR and Cryptomatte readers (corpus/exr)
Radiance HDR R/W yes yes f32
Portable Bit Map (PBM/PGM/PPM/PNM/PFM/PAM) R/W yes yes 8/16/32f
FITS R/W (FITS Liberator plug-in) yes yes 8/16/32f gray or RGB, header cards kept; no fpack, no debayer
Targa R/W yes yes 8-bit
Photoshop PDF R/W no (#2541) raster only (print, artboards to PDF) No vector/text PDF, no multi-page save, no PDF presentation (FILE-215-10)
Photoshop EPS, DCS 1.0/2.0, EPS TIFF/PICT preview R/W no no
Generic EPS / AI R (rasterize) no no
SVG R (rasterize) yes, as editable shape layers or a vector smart object no Better than Photoshop for editing; gradients approximated (FILE-215-9)
JPEG 2000 R/W no (#1047) no
Cineon / DPX R (DPX), R/W (CIN) no (#1049) no
DICOM R/W no no
PCX R/W no no
Pixar R/W no no
Amiga IFF R/W no no
Wireless Bitmap R/W no no
MPO / JPS (stereo) R/W no no
PICT R no no Legacy
Scitex CT R/W no no Legacy
Photoshop Raw (.raw) R/W no no
Camera raw (via Camera Raw 18.7) R partial – See below

Camera raw

Photoshop opens raws through Camera Raw 18.7 (the bundle registers cr2, crw, dcr, dng, erf, mos, fff, 3fr, mef, mfw, iiq, nrw, rwl, srw, mrw, nef, orf, pef, raf, srf, x3f; Camera Raw itself supports many more, including CR3).

Camera format PhotoCraft Evidence
DNG (incl. LJPEG and JPEG XL tiles) yes; lossy DNG no FILE-215-11
Canon CR2 yes
Canon CR3 detected, unsupported crates/raw/src/lib.rs:219
Nikon NEF/NRW (lossless, lossy) yes; "lossy after split" no #50; D5100 image area measured on three 14-bit lossy NEFs; validation
Sony ARW/SR2/SRF (incl. compressed) yes
Panasonic RW2, Pentax PEF yes
Olympus ORF uncompressed only
Fujifilm RAF (Bayer and X-Trans) uncompressed only; no Fuji colour calibration
Others (CRW, 3FR, IIQ, X3F, SRW, MRW, ERF…) embedded preview only
.xmp sidecars, highlight modes, raw preferences missing FILE-215-11
Camera Raw as a PSD smart filter partial 2026-10-07: WB, Light/Presence, curves, HSL, grading, detail, grain, vignette mapped (FILE-215-12)

2026-10-11: on #2135's embedded-JPEG rendering work, open-time Camera Raw tuning preserves the fitted rendering while changing Exposure, Temperature and Tint. Default tuned import matches normal import exactly; output remains full-resolution 16-bit ProPhoto. This improves appearance when a usable preview is present, without adding a measured D5100 colour profile. Counts and the G14 estimate are unchanged.

Formats Photoshop doesn't have (ours only)

Format Read Write Notes
.pcraft (native) yes yes Incremental, autosave, crash recovery, atomic save
Affinity .af, .afphoto, .afdesign, .afpub yes no See below
Paint.NET .pdn yes no pdn.md
OpenRaster .ora yes yes ora.md
ICO, QOI yes yes
Krita .kra, GIMP .xcf, Procreate no no Not in Photoshop either

Affinity import notes (moved from roadmap.md)

2026-10-08: Affinity .af, .afdesign, .afphoto and .afpub documents (container versions 8–12) open natively (format notes): pages and artboards, layers and groups, curves and geometric shapes with fills, gradients and strokes, text as type layers, placed images as smart objects, pixel layers and masks, as an 8-bit RGB document without a source save path. Measured against the thumbnail Affinity embeds in each file, 21 pinned public documents (cargo xtask corpus --affinity) differ by 0–4.6 of 255 on average. Layer effects, adjustments, live filters, brush strokes, special shapes, master pages and CMYK/Lab/16-bit document colour are approximated or left out, each with a warning; damaged or unknown files fall back to the embedded preview. Affinity writing is not implemented: no Affinity installation was available to check written files, so .af export stays unsupported.

2026-10-10: current .af artboard properties (phrp/aprp) are recognized alongside the legacy flag, including converted curve boards. Synthetic two-board regressions check separate bounds, overflow clipping, .pcraft/PSD board and pixel round trips, and moving one board with its children through undo/redo. Nested boards remain masked groups; rotated/curved board outlines still import at their bounding rectangle.

2026-10-09: corpus/affinity/ now has 39 pinned documents and 21 PNGs (20 rendered references and one bitmap-fill texture): the prior 21 public documents plus 18 CC0 samples for #1606. The new samples compare against their exported PNGs; mean differences range from 0.44/255 (conical gradients) to 86.05/255 (RGB/32 reduced to 8-bit). Clouds, hearts, cogs, callouts, arrows, double stars, tears, crescents, diamonds and circular segments now import as parametric shapes; the special-shapes sample measures 5.68/255 against its PNG. The remaining gaps in #1606 stay tracked with per-sample corpus ceilings.

Presets and data files

Format Photoshop PhotoCraft Notes
Brushes .abr R/W R/W psd/src/abr.rs (v6/v12)
Gradients .grd R/W R/W
Patterns .pat R/W R/W
Swatches .aco, .ase R/W R/W FILE-215-14
LUTs .cube / .3dl / .look R/W (Export Color Lookup) R/W / R / R cms/src/lutfile.rs
Keyboard shortcuts .kys R/W R engine/src/kys.rs
ICC profiles R R Own CMS
Actions .atn R/W no AUTO-219-2
Styles .asl R/W no #1693
Contours .shc, custom shapes .csh, tool presets .tpl R/W no FILE-215-15
Curves .acv, Levels .alv, other adjustment presets R/W not audited
C2PA Content Credentials R/W no #1050

Revision history

Date Change Summary
2026-10-12 minor Save writes a JPEG at its own estimated quality and a WebP lossy or lossless as opened (#2399)
2026-10-11 minor D5100 image area and fitted-look preservation in Camera Raw tuning
2026-10-10 major First version: Photoshop 2026 27.11.0's formats from its bundle, against our codecs; Affinity notes moved from roadmap.md