- `ExportOptions.hdr` (`hdr` param): photos edited in HDR export as ISO
21496-1 gain map JPEGs (the SDR rendition as the base, the gain map measured
against it as written) or 32-bit float TIFF with highlights above 1.
Other formats and SDR edits export as before.
- Output sharpening and watermarks apply to both renditions.
- `develop.hdr {enabled?, maxEv?}` turns HDR editing on/off and sets the
headroom limit.
Checked on macOS: ImageIO reports both the ISO and the Apple gain map, and
CoreImage's HDR decode of a 3 EV edit reaches 2.95 EV.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
`lightcraft_codecs::gainmap`:
- `compute` measures a gain map (luminance or RGB, log2, block-averaged)
from an SDR and an HDR rendition; `apply` rebuilds the HDR rendition.
- ISO 21496-1 metadata: writer (fixed denominator) and reader (also the
common-denominator form; refuses unknown versions, backward maps and zero
denominators). Adobe `hdrgm` XMP reader and writer, per-channel values as
rdf:Seq; Apple's HDRGainMap/HDRToneMap description of the same map.
- `encode_jpeg`: base with CIPA DC-007 MPF index (gain map typed 0x050000),
the ISO marker and Container XMP merged into the user's packet, followed by
the gain map JPEG. `read_jpeg` / `is_gain_map_jpeg` find and decode the map.
Also: gain map images are no longer picked as embedded thumbnails (an Ultra
HDR JPEG could show its greyscale gain map in the grid). The JPEG APP-segment
building is shared with `encode_jpeg`. Fuzzed with the other decoders.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
- `DevelopSettings.hdr`: enabled, headroom limit (`max_ev`) and SDR-rendition
offsets (brightness, contrast, highlights, shadows, whites, clarity), with
control specs (`hdr.maxEv`, `hdr.sdr*`) and copied with the Light group.
- `ToneMap::hdr` / `display_hdr`: the SDR curve through the midtones, with
highlights lifted up to `2^max_ev`; identical to the SDR tables at peak 1.
- `OutputDepth::F32Hdr`: unclamped linear output up to the peak. The finish
stage carries the peak through highlight desaturation, gamut mapping,
encoding, curves, grain and LUT profiles; with HDR off every branch is the
SDR code path, bit for bit.
- `settings_for`: every non-HDR render (CPU and GPU) uses the SDR rendition.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
preset, background, resize, subfolder, conflict, tiffCompression and
dngCompression were in the export tool's schema (and so passed the new
argument check) but were dropped before reaching app.export.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
std::process::exit skipped eframe's on_exit (ui.json, close_library) and the
may_close check, so changes still in memory could be lost on Cmd+Q.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
