Tanish MankuandClaude Opus 5
d0d1ad8192
pdfcraft_fonts::helvetica_width was a fifteen-line guess by character class, and seven crates generated appearance streams through it: annot, edit, forms, ocr, redact, sign and xfa. Times was Helvetica x 0.9, bold was x 1.05, Courier a flat 0.6. Against the published metrics a Times capital A is 722, so that estimate said 600 -- a 17% error on a letter, compounding across a line. Std14 carries the real advance widths for all fourteen faces, indexed by character code: WinAnsiEncoding for the twelve text fonts, which is what we write into the appearance streams we generate, and their own built-in encodings for Symbol and ZapfDingbats. The tables are generated by joining the published encodings with the per-glyph widths. helvetica_width now delegates, so every call site gained exact Helvetica with no change. The three places that faked another face by scaling it -- Family in edit::added, the paragraph measure in edit::text, and the redaction overlay fonts -- now select the right face instead. So does Metrics::width in fonts::pdf, which measures existing document text when a font carries no /Widths; that path feeds redaction's glyph removal, where a wrong width means cutting the wrong glyphs. Tests spot-check the table against values typed in from the specification by hand, so it is verified against the spec rather than against whatever produced it; plus Courier being fixed pitch everywhere, full printable-ASCII and Latin-1 coverage, Symbol and ZapfDingbats not being WinAnsi, /BaseFont aliases and subset prefixes resolving, and hostile text staying finite. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
pdfcraft-redact
Layer L4 (may use edit): redaction, architecture §11.2.
// Marks are Redact annotations (pdfcraft-annot: Shape::Redact { quads, overlay }).
let marks: Vec<Mark> = marks(&doc); // page, areas (user space), fill, overlay text
let report = apply(&mut doc, None)?; // everything, or Some(&[pages])
clear_marks(&mut doc, None)?; // remove marks without applying
apply removes, under every marked area:
- text: glyphs are cut out of
Tj/TJ/'/"and replaced by aTJdisplacement of the same advance, so the rest of the line keeps its exact position. Widths come from/Widths,/W//DW(composite fonts, embedded CMaps with codespace and CID ranges), Type 3 font matrices, and approximations for the standard 14. A glyph goes when it overlaps an area by more than a fifth of its size (or a point) both ways; zero-size text goes when its origin is inside; - images: fully covered → removed; partly covered → a copy with the covered pixels cleared (8/16-bit and 1/2/4-bit images, image masks; Flate/LZW/RL/A85/AHx). Codecs PdfCraft can't re-encode (DCT, JPX, JBIG2, CCITT) are removed whole (fail-closed); inline images under an area are removed;
- vectors: covered paths are removed; partly covered paths and shadings are clipped so nothing paints inside the areas;
- form XObjects: rewritten recursively into new objects (pages sharing the original keep it);
- annotations whose rectangle overlaps (with their pop-ups), and form fields with a widget under a mark;
- the marks themselves, replaced by boxes in their fill colour (and overlay text) drawn into the
page as a
/PCMark /Redactionstream.
A verification pass re-reads each redacted page and fails the operation if any glyph or inline image is still under an area. Content that can't be decoded makes the operation fail rather than leave it unredacted.
Structure cleanup resolves named MCIDs and indirect content references. Form content references are updated to the cleaned copy; unchanged sibling descriptions remain.
Remove hidden information / Sanitize
let found = sanitize::scan(&doc); // [(Hidden, count)] per category
sanitize::remove_hidden(&mut doc, &[Hidden::Comments])?; // chosen categories
sanitize::sanitize(&mut doc)?; // all of them
Categories: metadata (/Info, XMP), file attachments, comments, form fields (flattened so the
values stay visible), hidden text (render modes 3 and 7, or wholly off the page), hidden layers
(content of off optional-content groups, then the groups), bookmarks, links/actions/JavaScript,
and /PieceInfo private data. Both make the next save a full rewrite.
patterns finds phone numbers, e-mail addresses, credit card numbers (Luhn-checked), US Social
Security numbers and dates for Search & Redact.
codes holds the redaction code sets (U.S. FOIA and U.S. Privacy Act exemptions):
CodeSet::from_id("foia")?.overlay(&["(b)(6)"]) gives the overlay text for the picked codes.
Custom code sets aren't supported yet.
Not yet: pattern locales, struct-tree/alt-text cleanup, metadata and hidden-information sanitising (M8.4), re-encoding of DCT images (they are removed instead).