A flat TIFF dropped EXIF on export ("EXIF not supported") and ignored it
on import. TIFF is EXIF's own container: IFD0 points to the Exif (34665)
and GPS (34853) directories and holds the descriptive tags.
- Export: the EXIF block's Exif and GPS directories are written as
directories outside the page chain, IFD0 points to them, and IFD0's
descriptive tags (ImageDescription, Make, Model, Software, DateTime,
Artist, Copyright) are added unless the text metadata already wrote
them. Values are copied as bytes, reordered to the file's byte order,
so unknown tags survive.
- Import: a classic TIFF with an Exif or GPS directory gets an EXIF
block built from them and IFD0's descriptive tags.
- TIFF's format caps now include EXIF. Layered TIFFs keep EXIF as
resource 1058 as before (read back unchanged); the layered importer
already preferred the TIFF's own EXIF when there is one.
exiftool and Photoshop 2025 read the Exif and GPS tags of such a TIFF.
Fixes#4875
* Add FITS read/write codec
FITS (the astronomy format) opens and saves as a flat image: the primary
HDU or first IMAGE extension; gray, or RGB when NAXIS3 = 3; BITPIX 8/16/
32/64/-32/-64 with BSCALE/BZERO/BLANK; rows follow ROWORDER (bottom-up by
default). Camera U16 data stays exact; float data is normalised to 0..1.
Header cards round-trip as text metadata (HIERARCH for long names).
Tile-compressed (fpack) files are refused as unsupported.
Wired into File > Open, Save As and the batch commands as .fits/.fit/.fts.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* Test FITS open and save through photocraft-io
Gray 16-bit, RGB 8-bit and RGB 32-bit float documents round-trip exactly,
and header cards travel as the document's text metadata.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* FITS: hostile-header regression test (absurd axes, bad BITPIX, no END, HDU chains, overflowing sizes)
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
---------
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
Co-authored-by: Brandon Thomas <echelon@gmail.com>
* Layered TIFF: open and save Photoshop layer data in TIFF files, in either byte order (part of #215)
Photoshop keeps a layered TIFF's layers in two private tags: 37724 (ImageSourceData, the same
layer section a PSD has) and 34377 (the image resources). PhotoCraft now reads and writes both,
so a TIFF opens with its groups, masks, layer styles, type, shapes, smart objects and adjustment
layers exactly as the PSD path would, and saves them back.
* photocraft-psd: a `tiff` module with `ImageSourceData` (parse/write, PSD- and PSB-sized),
the 34377 resource helpers, and a field-by-field byte-order transcoder. In Intel-order TIFFs
Photoshop byte-swaps the whole block structure (reversed keys, little-endian integers and
doubles) while pixel samples stay big-endian; the transcoder knows the layer-info structure,
masks, blending ranges and every block photocraft-io maps (descriptors, TySh, lrFX, the
binary adjustments, paths, patterns, filter effects, metadata settings, linked layers,
annotations...), recognizes descriptor-shaped unknown blocks, and drops the rest with a
warning instead of passing byte-swapped data to other readers. The reader gained an optional
little-endian mode. 23 unit tests; a fuzz target in the CI matrix.
* photocraft-codecs: the two tags travel as opaque bytes on `Metadata`, read by a
bounds-checked walk of IFD0 (classic and BigTIFF, both byte orders) and written back as
BYTE / UNDEFINED tags. `tiff_writes_little_endian()` tells which order the encoder produces.
* photocraft-io: `tiff_layers` rebuilds a PSD model from the TIFF's pixels plus the tags on
import, and on export runs the PSD exporter (new `merged_matte` / `merged_compression`
options), interleaves its merged planes for the TIFF image and stores the layer section in
the encoder's byte order. `ExportOptions.tiff_layers` (default on). Lab and Multichannel
documents save flat; extra alpha channels are not written (one transparency sample).
* UI: the TIFF Options prompt ("Including layers will increase file size." / "Discard Layers
and Save a Copy" / "Don't show again") behind Preferences > File Handling > Ask Before
Saving Layered TIFF Files; `ExportSettings.tiff_layers`; catalogs updated.
* Tests: io round trips at 8/16/32 bits in Gray/RGB/CMYK, equivalence with the PSD path, every
TIFF compression, the flat fall-backs, malformed input, and files written by psdtags in both
byte orders (fixtures from scripts/layered_tiff_fixtures.py); a corpus test (feature
`corpus`) writes every corpus PSD as a layered TIFF and compares the result with the PSD
round trip (700 files, 0 differences, 0 crashes). Codecs tests cover the tag walk on
hand-made files.
* Scorecard FILE-215-7 done, BUG-204-3 partial; README and book updated.
Co-Authored-By: Claude Mythos 5.1 <noreply@anthropic.com>
* Layered TIFF: de and pt-br strings; neutral wording in the psd tiff docs
The four psdtags fixtures stay out of the repository (no binary test data here): the
generator now writes them to the gitignored corpus/layered-tiff/, and the tests that read
them skip with a message when absent.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* Regenerate docs/scorecard.md
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
---------
Co-authored-by: leon <claude.udder842@passmail.net>
Co-authored-by: Claude Mythos 5.1 <noreply@anthropic.com>
Co-authored-by: Brandon Thomas <echelon@gmail.com>
A JPEG holds XMP in one APP1 segment, at most 65,533 bytes. Documents
from the source application often carry far more: their XMP lists every
document ever placed in them (DocumentAncestors, thousands of ids) and
the text of every type layer (TextLayers). The encoder passed the packet
through whole, the segment was refused, and the export failed with "App
segment exceeds maximum allowed data length of 65533". That stopped
every JPEG path: Export As, Save a Copy, convert, Layers and Artboards to
Files, Batch and Image Processor. 3 of 16 real designer documents in a
sweep hit it.
When the packet doesn't fit, the encoder now leaves out those two
layered-document properties (any namespace prefix), which a flat image
doesn't need; everything else in the packet is kept. If it still
doesn't fit, the XMP is left out, and so is an EXIF block over 64 KB.
Both cases are reported ahead of time by a new fidelity warning,
MetadataTooLarge, so the export shows what was dropped. Formats without
a segment limit (PNG, TIFF, WebP) still keep the packet whole.
Test: jpeg_with_oversized_metadata_still_encodes (fails before: encode
error), at 8, 16 and 32 bits.
Co-authored-by: EthanSuquet <292885762+EthanSuquet@users.noreply.github.com>
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
CI's `cargo fmt --all -- --check` has failed on every run because the
repo had no rustfmt config and was never formatted. Use the same settings
as EffectCraft/FilmCraft (max_width 160, use_small_heuristics Max), which
also keeps the churn small. Formatting only; no code changes.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Gert Pellin - GPE