aiongg
24a472717a
* hayro-interpret: ink colors, overprint and font bytes for the flattener Local patches for craft-prepress's PDF-in adapter, labeled Craft patch (flatten) and listed in vendor/README.craft-reader.md: - Device::set_overprint and Device::set_isolated, called where the blend mode is set and after an isolated group is pushed. - Color::ink_paint, ColorSpace::ink_space and ink_values: colors and image samples as the inks they print, without converting to RGB. RasterImage::with_inks gives native samples with Decode and Matte. - OutlineFontData::embedded and index, and the CFF bytes of Type1C fonts, so text can be embedded again. - The sh operator ignores /Background (ISO 32000-2 8.7.4.5.1). * plate-test: flattened-page checks, image alpha and scenes F01, F02 - report::run_flattened separates each scene's page after a caller's flattener as well as the original, and structure::transparency lists what transparency a page still has. plate-test doesn't depend on the flattener. - Scene images take an alpha channel, written as /SMask. - F01: a partly transparent image over a flat fill; where its alpha is 0 the fill keeps its exact inks (vectorcraft#2160). - F02: art hidden under opaque fills leaves no trace after flattening (vectorcraft#2161). * prepress: transparency flattener (flatten feature) craft_prepress::flatten turns PDF pages with transparency into pages without it, keeping inks, overprint and live text, for PDF/X-1a and other output that can't carry transparency. - pdf: reads a page into a display list in inks through hayro-interpret: paths, outlined strokes, clips, groups, soft masks, overprint, spot and DeviceN colors, images in their own color space, gradients, rasterized mesh shadings, tiling patterns and glyph runs. - font: prepares the source fonts for embedding again (TrueType, OpenType, CFF wrapped as OpenType); others fall back to outlines with ActualText. - geom: planar regions with the shapes that cover each one (linesweeper). - compose: composites each region per ink (separable and non-separable blend modes, isolated and knockout groups, overprint per plate as ISO 32000 defines it); regions under images, gradients and soft masks are marked complex. - raster: complex regions as DeviceN images through plate mode, grid snapped with a one-pixel outset; flatten_page. - write: writes the result with the vendored krilla; flatten_document writes every page into one PDF with the output intent, page boxes and fonts shared across pages when their bytes match. The regions and the compositor are ported from VectorCraft (commit c2b15982, crates/pathops and crates/engine/src/cmd/flatten.rs), credited in the crate README. scripts/plate-check.sh --flatten separates every scene's flattened page with Ghostscript (local only). CI runs craft-prepress with all features. * krilla: DeviceN /Colorants from PDF 1.3, NChannel attributes from 1.6 (patch 11) * prepress: flatten_document output PDF version and PDF/X version * prepress: format the PDF/X-1a flatten test * krilla, craft-prepress: write GTS_PDFXConformance next to GTS_PDFXVersion PDF/X-1a:2003 files carry GTS_PDFXVersion (PDF/X-1:2003) and GTS_PDFXConformance (PDF/X-1a:2003). Krilla patch 12 adds SerializeSettings::pdfx_conformance, and FlattenDocumentOptions passes it through. * krilla, craft-pdf, craft-prepress: carry the modification date over Krilla patch 13 adds Metadata::modification_date, written as /ModDate and xmp:ModifyDate in place of the creation date. craft-pdf's Metadata gains modified, and flatten_document takes it from the source's ModDate. * craft-prepress: count the print annotations a read leaves out ReadReport::dropped_annotations counts the annotations a printer would paint (Print flag, not Hidden, with a normal appearance) when ReadOptions::annotations is false; FlattenTotals sums it. * craft-prepress: degenerate groups rasterize without a soft mask A group the region sweep fails on is clipped to its members' boxes, which no other group's items reach, so the paper is its only backdrop. Its image is written opaque, as the plates of the items over paper, and the page keeps no transparency for PDF/X-1a. * craft-prepress: write untouched JPEG images as they are A DCT-encoded DeviceGray or DeviceCMYK image that krilla's JPEG passthrough writes with the same meaning (8 bits, no decode parameters, the default gray Decode or the inverted Adobe CMYK one) keeps its data in ImageItem::jpeg, and the writer embeds it unchanged when the image has no soft mask. Other images are still 8-bit Flate samples. * craft-prepress: keep group members with no transparency above them Groups are transitive by bounding box, so a background frame put all the body text on it under a transparent object far away, and the text came back as outlined fills. A member is now drawn as it is when it is opaque and, in every region its shapes are in, only members kept this way are above it. The region fills under it are the composite of the other members, and it is drawn over them in paint order. * prepress: keep the backdrop under elements of a knockout group * prepress: rasterize complex regions thinner than a point * prepress: mark flatten errors, reasons and reports non_exhaustive * prepress: bound the items a tiling pattern fill expands into Each of up to MAX_TILING_CELLS cells copied the whole cell content, and a cell can hold many items or an expanded pattern of its own. A fill whose cells would hold more than MAX_TILING_ITEMS items in all, counting groups, masks and nested patterns, is read as an image. * prepress: stroke solid past the dash budget A dash pattern that cuts a stroke into more than 250,000 pieces is outlined solid, with the estimate hayro's renderer uses. * prepress: bound the sampling and memory of rasterized tiling patterns Each pixel sampled every cell over it, which for a BBox far larger than its step is millions of cells per pixel; past MAX_TILING_CELLS cells per pixel the fill paints nothing, and below it the image resolution drops to keep the samples within MAX_TILING_SAMPLES. The canvases also hold a value per page ink, so their pixel limits shrink with the ink count to keep the memory of CMYK canvases, and the canvas size uses checked arithmetic. * prepress: mark the page reader's error and report non_exhaustive * prepress: format the tiling tests * prepress: CodeRabbit fixes: no nonzero overprint mode for images and shadings, count dropped tilings, widen the hhea ascender * prepress: refuse DeviceN spaces past the output's colorant limit and regions past the separated spot inks
hayro-interpret
A crate for interpreting PDF files.
This crate provides an abstraction to interpret the content of a PDF file and render them
into an abstract [Device], which clients can implement as needed. This allows you, for
example, to render PDF files to bitmaps (which is what the hayro crate does), or other formats
such as SVG.
It should be noted that this crate is still very much in development. Therefore it currently lacks pretty much any documentation on how to use it. It's current API also only really makes it useful for rendering to PNG or SVG, though this will be improved upon in the future.
Examples
See the examples folder on the GitHub repository. Apart from that, you can also consult
the implementation of hayro and hayro-svg to get an idea on how to use this crate.
Safety
This crate forbids unsafe code via a crate-level attribute.
Cargo features
This crate has one optional feature:
embed-fonts: PDF processors are required to support 14 predefined fonts that do not need to be embedded into a PDF file. If you enable this feature, hayro will embed a (permissively-licensed) substitute for each font, so that you don't have to implement your custom font loading logic. This will add around ~240KB to your binary.
License
Licensed under either of
- Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
- MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)
at your option.
PdfCraft function limits
The PdfCraft patch rejects function construction after 64 nested functions or 10,000 total
function nodes, including repeated references, and detects cycles on the current path. Shared
children in different branches remain valid. Stitching functions reject empty or unresolved
child lists instead of silently truncating them. Calculator functions have a shared limit of 64
procedure levels and 10,000 parsed tokens (operators and procedure openings); evaluation has
its own 10,000-operator limit across selected branches. These are implementation resource
limits rather than PDF format limits. Rejection returns the existing None, and the optional
logging feature reports the reason and limit; no new interface warning is introduced.
Calculator integer division without an integer result is also rejected. Bit shifting discards bits beyond the 32-bit word and fills with zeroes, including logical right shifts of negative words; rotation accepts the full signed shift range without negating the minimum integer. Fixed-size operand and procedure-stack overflow errors propagate instead of truncating work. Normal function signatures and supported color/transfer-function behavior remain unchanged.