SystemFontProvider.NOTO_FONT_PATTERNS enumerates about two dozen Noto
families by name, and MultiFontManager only ever asked for those. Any
script outside that list fell through to the glyphless Occulta fallback
even when the correct font was installed, which is the common case on
macOS: it ships around a hundred script-specific Noto faces in
/System/Library/Fonts/Supplemental, almost none of which we knew how to
ask for. The reporter had the fonts and still got told to install them.
Add an optional GlyphSearchingFontProvider protocol (find_font_with_glyphs)
implemented by SystemFontProvider, BuiltinFontProvider and
ChainedFontProvider, and a new selection phase that uses it once the named
families fail. The system scan enumerates every Noto face, reusing the
existing variable-font/-Regular/-VF filename classification, and keeps
only the font it selects so a full scan does not retain every font file on
the system. Fonts found this way are remembered and retried by name for
later words. Capability detection is isinstance-based so third-party
providers keep working unchanged.
The warning itself was also unactionable: it named neither the characters
nor the script, which is why the reporter had to ask which package to
install. It now identifies what it could not render, e.g.
'Ꮳ' U+13E3 CHEROKEE LETTER TSA. A word mixing scripts that no single font
covers now gets a distinct message saying that installing fonts will not
help, rather than sending the user after fonts they already have.
Finally, the documented macOS install command was wrong: `brew install
font-noto` does not exist, since Homebrew has no single Noto package, only
a cask per family. The Fedora package name was also corrected, as
google-noto-fonts-common ships no actual fonts.
Ghostscript's PDF/A conversion re-embeds non-embedded CID (CJK) fonts by
substituting a system font, which corrupts the character-to-Unicode
mapping and silently destroys an existing text layer -- commonly the OCR
layer Adobe Acrobat adds to scanned CJK documents.
Detect non-embedded CID/Type0 fonts before conversion: with
--output-type auto (the default) downgrade to a regular PDF and preserve
the text layer; with an explicit --output-type pdfa* stop with an error
rather than emit corrupted output. Simple non-embedded fonts (e.g. Latin)
are left alone -- Ghostscript substitutes them without corrupting the
text, and they are far too common to treat as conversion blockers.
Use --output-type pdf to keep the existing text layer, or --force-ocr to
rebuild it with embedded fonts.
Writing the output PDF to stdout (ocrmypdf in.pdf -) previously relied on
an honor system: no in-process code -- third-party libraries, plugins, or
stray print() calls -- was supposed to write to stdout, enforced only
indirectly. A single accidental write to fd 1 would silently corrupt the
output PDF.
Enforce this at the OS level. At CLI startup, before plugins load or any
worker process/thread starts, save the real stdout via os.dup() and point
fd 1 at stderr, so stray writes are diverted to stderr while only the final
"produce the PDF" step writes to the preserved descriptor. Exposed as the
opt-in public API function configure_stdout_protection(), mirroring
configure_logging(); it is not enabled inside ocr() so in-process library
users keep their own stdout.
Also fix check_requested_output_file() to test the preserved real stdout
for tty-ness, since after the redirect sys.stdout reports stderr's status.
Fold unreleased v17.7.2 notes into v17.8.0.
Some PDFs use a /Name dictionary key in /DocumentInfo whose bytes are not
valid UTF-8/PDFDocEncoding, e.g. a Latin-1 /Saks#e5r. Older pikepdf raised
UnicodeDecodeError while iterating such a block, crashing the pipeline
during PDF/A conversion. repair_docinfo_nuls is documented to log and
continue on a malformed DocumentInfo block, so catch UnicodeDecodeError
alongside TypeError.
Add a mock-based unit test that drives the decode-error branch (current
pikepdf surrogate-escapes instead of raising) and an end-to-end test over
the reporter's file, committed as docinfo_latin1_key.pdf.
Since v16.4.3, OCRmyPDF forced pdfminer's read buffer to 256 MiB to work
around a pdfminer bug that mishandled tokens split across the buffer
boundary (gh #1361). On Windows this caused a severe performance
regression (gh #1662): CPython's BufferedReader.read(n) eagerly allocates
an n-byte buffer on every read, so pdfminer's thousands of seek+read
cycles each paid a ~30 ms 256 MiB allocation (this allocation is lazy and
effectively free on Linux). For a typical PDF the "Scanning contents"
phase went from ~5s on Linux to ~60s on Windows.
The underlying pdfminer bug was fixed upstream in pdfminer.six 20250327
(pdfminer/pdfminer.six#1030), with a follow-up for tokens split across
streams in 20260107 (pdfminer/pdfminer.six#1158). Remove the monkeypatch
entirely and raise the minimum pdfminer.six to 20260107 so we rely on the
upstream fix instead.
Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>
Adds a processing mode that removes the invisible (render mode 3) OCR text
layer in place. Unlike `--ocr-engine none --force-ocr`, it does not
rasterize the page, so images and visible content are preserved unchanged
and the output is smaller rather than larger. Options that require
rasterization or OCR (--deskew, --clean, --sidecar, etc.) are rejected.
Only invisible text is removed; text drawn as visible glyphs under an
opaque image (some OCR engines, and OCRmyPDF v2.2 and earlier) cannot be
removed this way, as documented.
Closes#1435.
When Tesseract reports a page with many diacritics, OCRmyPDF rewrites the
message to "lots of diacritics - possibly poor OCR", which hid the
original wording. Keep the interpreted hint but also emit Tesseract's raw
line at debug verbosity (-v 1) so users can see exactly what Tesseract
reported.
Closes#1566.
Ghostscript 10.x renders aliased glyphs that OCR frequently misreads as
extra word breaks or substituted characters. Enable text and graphics
anti-aliasing (-dTextAlphaBits=4 -dGraphicsAlphaBits=4) for the contone
raster devices, which empirically improves OCR accuracy on the
Ghostscript path, especially for small fonts at moderate DPI. The 1-bit
mono devices are excluded, since older Ghostscript rejects alpha bits on
them and pngmonod performs its own anti-aliased downscaling.
Also log which rasterizer rendered each page at debug verbosity and
clarify the --rasterizer help text, so quality reports are easier to
diagnose. The default rasterizer (auto) already prefers pypdfium2, which
anti-aliases; this primarily benefits --rasterizer ghostscript and
installs without pypdfium2.
Closes#1439.
The optimizer is best-effort: any image it cannot process is left
unchanged in the output, which remains valid. Previously, an extraction
failure (e.g. an exotic colorspace pikepdf cannot transcode) was logged
with log.exception, printing a full traceback at ERROR level that alarmed
users even though nothing was wrong with the output (issue #846).
Trap such failures with a concise warning that the image was left
unchanged and the output is still valid, and demote the traceback to
debug verbosity for diagnosis.
Ghostscript's `auto` image compression heuristic can transcode lossless
images to JPEG during PDF/A generation, which is surprising at
optimization levels that otherwise promise lossless-only operations
(issue #1124).
`--pdfa-image-compression=auto` (the default) now coerces to lossless at
-O0 so Ghostscript will not transcode lossless images to JPEG. -O1 and
above continue to defer to Ghostscript's heuristic; -O1 (the default
level) is kept as a historical exception because coercing it to lossless
substantially bloats output. Users wanting guaranteed lossless image
handling can pass --pdfa-image-compression=lossless or use -O0.
Also make `lossless` pass existing JPEGs through unchanged
(-dPassThroughJPEGImages=true) instead of re-encoding them with a
lossless codec, which only inflates already-lossy data.
Validate and repair the page-boundary boxes (MediaBox, CropBox, TrimBox,
ArtBox, BleedBox) of input PDFs in triage(), following PDF 2.0:
- Coerce coordinates written in invalid exponential notation, stored by
qpdf/pikepdf as strings (#1398).
- Normalize rectangles whose corners are given in reversed order, which
previously crashed with NegativeDimensionError (#1526).
- Clamp a crop/trim/art/bleed box that extends outside the MediaBox to
their intersection, or discard it when the intersection is empty, which
previously produced a zero-height effective page some viewers rejected
(#1400).
When a box is discarded, clamped, or reinterpreted, a warning recommends
visual inspection of the output. pdfinfo box reading shares the same
coercion helper so PdfInfo no longer crashes on malformed boxes.
Supersedes PR #1691. Thanks @ajdlinux.
Closes#1398, #1526, #1400
A page may carry an optional /Thumb image XObject (ISO 32000-2 12.3.4),
a miniature rendering used only as a navigation aid. OCRmyPDF alters
page appearance (deskew, clean, rasterize, re-render) and plugins may
edit pages arbitrarily, so a retained thumbnail would be stale and no
longer match its page. Modern viewers generate thumbnails on demand, so
there is no loss of functionality.
OcrGrafter.finalize() now strips /Thumb from every page before saving,
alongside the existing search-index discard, covering both the OCR and
hOCR pipelines. Orphaned thumbnail XObjects are garbage-collected on save.
Adobe Acrobat can embed a proprietary full-text search index in the
document catalog at /Root/PieceInfo/SearchIndex. Only Acrobat reads it;
other viewers ignore it and search the text on the fly. Any change to a
PDF invalidates the index, so once OCRmyPDF rewrites the document the
retained index is stale and returns incorrect search results in Acrobat.
OcrGrafter.finalize() now discards it before saving (covering both the
OCR and hOCR pipelines), preserving any other PieceInfo owner data and
dropping an empty PieceInfo. Modern viewers rebuild a search index on
demand, so there is no loss of search capability.
The API previously clobbered PIL.Image.MAX_IMAGE_PIXELS unconditionally
on every call, so host applications (e.g. Paperless-NGX) that configured
the PIL limit before invoking ocrmypdf.ocr() saw their setting silently
overwritten with the 250 MP default. Make max_image_mpixels default to
None and only apply the override when the caller explicitly sets it.
The CLI default of 250 MP is unchanged.
Fixes#1665
James R. Barlow
