80 lines
5.8 KiB
Markdown
80 lines
5.8 KiB
Markdown
# File format parity
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> **Last reviewed:** 2026-10-10 · **Last updated:** 2026-10-10 · **Change:** major (created; formats measured from the code and the target's Info.plist) · **Target:** Adobe Lightroom Classic 15.5 / Lightroom 9.6
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Every format Lightroom reads or writes, with our support, fidelity and tests. Camera raw formats are
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deep enough to have their own document: [raw-parity.md](raw-parity.md).
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**How measured:** the target's document types come from the installed Lightroom 9.6
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`Info.plist` (`CFBundleDocumentTypes`: catalog `mcat`, `xmp`, toolkit / module / library bundles, and
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the raw-and-image list: jpg, tif, dng, heic and 27 raw extensions) plus Lightroom Classic's documented
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import and export formats. Ours come from `crates/codecs/src/sniff.rs`, `crates/codecs/src/encode.rs`,
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`crates/engine/src/export.rs`, `crates/engine/src/import.rs` and the tests named below.
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## Images (non-raw)
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| Format | Target reads | Target writes | LightCraft reads | LightCraft writes | Notes / tests |
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|---|---|---|---|---|---|
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| JPEG | ✅ | ✅ | ✅ (parallel decoder, ICC, EXIF orientation) | ✅ quality, size limit, ICC, metadata | `crates/codecs/src/jpeg.rs`, export tests |
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| TIFF | ✅ 8/16/32-bit | ✅ 8/16-bit, LZW/ZIP | ✅ 1–64-bit integer, 16–64-bit float, bilevel, CCITT fax, WhiteIsZero | ✅ 8/16-bit, 32-bit float linear, none / LZW / ZIP | `crates/tiff`, `crates/codecs/src/tiff_codec.rs` |
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| PNG | ✅ | ✅ | ✅ | ✅ | |
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| PSD / PSB | ✅ (maximized-compatibility composite) | ✅ (Classic: PSD export, edit-in round trip) | ✅ merged composite | ⬜ (external-editor round trip writes 16-bit TIFF) | `crates/codecs/src/psd.rs` |
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| HEIC / HEIF | ✅ | ⬜ (Classic) / HDR only | ✅ in every release build (`crates/heif`, heic-rs) | ⬜ | `heif` feature on by packaging scripts |
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| AVIF | ✅ | ✅ (HDR) | ⬜ recognised, not decoded (no permissive pure-Rust AV1 decoder) | ✅ 8/10-bit, PQ HDR | |
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| JPEG XL | ✅ | ✅ | ✅ (`jxl-oxide`) incl. DNG 1.7 JXL tiles | ⬜ | |
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| WebP | not in its document types | ⬜ | ✅ | ✅ | beyond target |
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| GIF, BMP | ⬜ | ⬜ | ✅ | ⬜ | beyond target |
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| DNG (from raw) | ✅ | ✅ incl. lossy, embedded original | ✅ | ✅ uncompressed or LJ92; ⬜ lossy DNG, embedded original | `crates/raw/src/dngwrite.rs` |
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| Render to DNG (15.5) | — | ✅ | — | ⬜ | new in Classic 15.5 |
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| Original + sidecar | — | ✅ | — | ✅ | |
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| HDR gain map JPEG (ISO 21496-1) | ✅ | ✅ | ✅ (gain map read) | ✅ | `crates/codecs/src/gainmap.rs` |
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| PQ / HLG HDR | ✅ | ✅ AVIF, JXL, TIFF | — | 🟡 PQ AVIF, float TIFF; no HLG | |
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| Contact sheet / print PDF | — | ✅ (Print module: PDF / JPEG / printer) | — | 🟡 paginated contact-sheet PDF (A4 / Letter, 150 dpi, sRGB) | `crates/engine/src/contact_sheet.rs` |
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| Video (MP4, MOV, AVCHD…) | ✅ playback, trim, edit | ✅ export | 🟡 catalogued (kind, duration) | ⬜ | see video gap |
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## Colour spaces and profiles
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| Feature | Target | LightCraft |
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|---|---|---|
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| Export colour spaces | sRGB, Adobe RGB, Display P3, ProPhoto, Rec.2020, custom ICC | ✅ sRGB, Display P3, Adobe RGB-compatible, ProPhoto, Rec.2020 with gamut mapping (CPU and GPU), embedded ICC; ⬜ custom ICC output profiles; AVIF stays sRGB |
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| Input ICC (JPEG / TIFF / PNG) | ✅ | ✅ matrix / TRC and LUT profiles (moxcms) |
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| Soft proofing with printer profiles | ✅ | 🟡 |
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## Metadata, sidecars, presets and catalogs
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| Format | Target | LightCraft | Notes |
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|---|---|---|---|
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| XMP sidecars (`crs:` develop settings, ratings, keywords, regions) | read / write | ✅ read / write, manual (⌘S) and automatic | [xmp-interop.md](xmp-interop.md) |
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| EXIF / IPTC / XMP embedded on export | ✅ | ✅ with metadata filters | `crates/meta` |
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| Develop presets `.xmp` | ✅ | ✅ import (mapping of supported settings) | |
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| Legacy presets `.lrtemplate` | ✅ (converted) | ✅ import | |
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| Camera / creative profiles (`.dcp`, `.xmp` profiles) | ✅ | ⬜ deliberately (Adobe profile formats are never used); `.cube` LUT profiles ✅ | |
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| Lens profiles `.lcp` | ✅ | ⬜ deliberately | |
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| Other apps' presets | — | ✅ Luminar `.lmp` / `.mplumpack`, `.zip` bundles | beyond target |
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| Lightroom Classic catalog `.lrcat` | native | 🟡 import (ratings, flags, labels, keywords, collections, virtual copies, supported develop settings; read-only pure-Rust SQLite incl. WAL) | [lightroom-catalog-import.md](lightroom-catalog-import.md) |
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| Lightroom (cloud) library `.lrlibrary` | native | ⬜ | cloud library format, local cache only |
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| Write back to `.lrcat` | native | ⬜ (one-way migration by design) | |
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| Keyword lists (text) | import / export | ✅ | |
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| GPX track logs | ✅ | ✅ | `crates/meta/src/gpx.rs` |
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| Export presets, metadata presets, filename templates | ✅ (`.lrtemplate`) | ✅ own JSON | not interchangeable |
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| Lightroom plug-ins (`.lrplugin`, `.lrdevplugin`) | ✅ | ⬜ | see ecosystem in [target-app-parity.md](target-app-parity.md) |
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## Scores
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| Part | Weight | Ready for real work | Kind |
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|---|---:|---:|---|
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| Standard image import / export | 35% | ~85% | estimated (table above; missing: AVIF read, JXL / PSD write, lossy DNG) |
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| Sidecars, metadata, presets | 25% | ~85% | estimated |
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| Lightroom catalog migration | 25% | ~50% | estimated (one-way, approximate rendering of unsupported settings) |
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| HDR, print, video output | 15% | ~35% | estimated |
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| **Non-raw file formats** | 100% | **~70%** | estimated; raw is in [raw-parity.md](raw-parity.md) (~50%) |
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Remaining: **30–55 h** (AVIF decode 8–15 h if a permissive decoder is written or found; JXL encode
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4–8 h; PSD write 4–8 h; lossy DNG and Render to DNG 4–8 h; HLG 3–5 h; catalog import depth 8–12 h).
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## Revision history
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| Date | Change | Summary |
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|---|---|---|
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| 2026-10-10 | major | Created from the code and the installed Lightroom's document types |
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