`decode_with_damage` and `decode_contents_with_damage` read a stream's
`/DecodeParms` only when direct, as `Stream::decoded` does, so content behind
a predictor whose parameters, or a number in them, are an indirect object
decoded with the predictor's tag bytes left in, and was taken as whole. Edit
then listed and wrote back the wrong bytes, and pruning dropped an image such
a form draws. ISO 32000-2 lets those values be indirect.
- `decode_with_damage` takes the document and reads the parameters through
it, and so does `decode_contents_with_damage`, and `decode_contents` with
it: printing, accessibility's reading of a page and a page copied as a form
read them too. Code that calls `decode` on a stream itself doesn't yet.
- It reads through `Document::decoding_view`: `with_direct_parms`, but a copy
of the stream holds only its `/Filter` and the parameters, its data shared,
so a stream a page's `/Contents` lists again and again isn't copied whole
for each.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AmsdeUCdTaD72jkDw2pJKY
Optimize read a page's content up to any damage in its streams as the whole
of it. Merging a page's image strips then wrote the page's content again as
one stream, without what followed the damage, and the image pass measured
each image by its uses before the damage only, so one drawn larger past it
could be resampled below that use.
- `DecodeBudget::decode_contents_with_damage` reads a page's `/Contents` as
`decode_contents` does, each stream also saying whether it is damaged
partway; `decode_contents` is it without the flag.
- `content_bytes` gives `None` for a page with a damaged stream, as for one
that doesn't decode: the content is not all known. Its strips aren't merged
(`merge_page` already leaves such a page alone), and no image is resampled
(`effective_resolutions` gives every image `INFINITY`).
- A form damaged partway leaves the measuring incomplete in the same way.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AmsdeUCdTaD72jkDw2pJKY
Merge origin/main. Conflicts: docs/changelog headers keep both histories;
edit/run.rs keeps EnhanceScan beside main's run_edit_page_image; optimize
images.rs keeps main's scaled() and the crate-visible jpeg(); the German
strings in ui-egui/src/i18n/de.tsv go with that file, which main moved to
craft-i18n. decode_samples now takes main's ImageBudget; a scan clean-up
run shares one sized by the file.
Review (CodeRabbit, scan_clean.rs): a page whose own images and a
scan-holding Form only together cover it now cleans the images and reports
the Form; a page whose images alone cover it reports its Form too. New
regression fails on the old classification.
* M11: JBIG2 images share a symbol dictionary, up to 16 at a time
With Monochrome Images set to JBIG2, Optimize stored each image's
letters in a symbol dictionary of its own, so a document of N pages
carried its font's shapes N times. Now up to 16 images the run stores
as JBIG2 share one dictionary in a /JBIG2Globals stream, holding the
marks found in more than one of them; each image's text regions refer
to it first, then to a dictionary of its own for the marks only it
repeats. An image is stored that way when it comes out smaller, and a
group only when what its images save is more than the globals take.
- filters: encode_jbig2_shared codes a group: the globals are a symbol
dictionary segment numbered 0 and associated with no page (7.2.6);
each page numbers its segments from 1, as a segment refers only to
lower numbers (7.2.5), and the shared symbols' IDs come first, as the
dictionaries are referred to in that order (Table 31, SBSYMS). At
most 16,383 shared marks, those in the most images, so a page keeps
room for its own under the decoder's 32,767.
- optimize: the run holds the 1-bit samples of the images it stores as
JBIG2 (16 at most, 64 MiB at most) and stores them again sharing,
weighing each with the longest reference the globals could have.
Eight pages of 10 pt text rendered at 300 dpi take 41% less in
Helvetica and 42% in Times than coded alone, 10% in Courier, and 46%
in Helvetica at 600 dpi; groups of 2, 4, 16 and 32 save 19%, 33%, 45%
and 47%. Redacting one image stores the others of its group again
without the dictionary, so 16 keeps that to 15 images.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AmsdeUCdTaD72jkDw2pJKY
* M11: test what the mutants found untested in shared JBIG2 dictionaries
- filters: the group goes through encode_jbig2_shared, which refuses it
for an image the encoder refuses; two marks in common are enough to
share; past the 65,536 distinct marks a group holds, a mark first seen
later isn't shared while those held count every image.
- optimize: optimizing again keeps both the shared pages and the pages
coded alone as they are; under Retain, averaged JBIG2 pages share
nothing; a last group of two shares.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AmsdeUCdTaD72jkDw2pJKY
* M11: only images redaction can store again share a JBIG2 dictionary
Redacting one image of a group stores the others again without the
dictionary, which can hold the shapes of marks under the area, and
refuses the redaction for one it can't: it takes image masks and
images of one component as its own reading counts them (no DeviceN,
the family named directly), and at most 64 Mi pixels. Optimize took
DeviceN of one colourant and up to 80 million pixels, so such an image
in a group made any redaction of the others fail, where before it was
coded alone and the same redaction worked (the Consumers review).
Only an image mask or a DeviceGray image named directly, of at most
2^26 pixels, now joins a group; others are coded alone. An engine test
optimizes three pages, two DeviceGray and one DeviceN, and redacts the
first: the DeviceN page stays alone, the second is stored again, and
no image names the dictionary after a save.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AmsdeUCdTaD72jkDw2pJKY
* M11: optimize and redaction share one limit on the images redaction stores again
The second Consumers review: Optimize's limit on images that share a
JBIG2 dictionary copied redaction's private 64 Mi, with nothing tying
the two, so a lower one in redaction would bring back refused
redactions with no test going red. Both now read
pdfcraft_cos::MAX_REDACTED_IMAGE_PIXELS. The engine test adds an image
mask, the other kind that shares, so a redaction that stopped storing
either kind again fails it. doc_optimize's description, the README,
the parity note and ROADMAP say which images share (named directly).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AmsdeUCdTaD72jkDw2pJKY
* M11: a JBIG2 group is coded before its samples would pass the limit
CodeRabbit on #5910: hold added an image to the group and then checked
SHARED_BYTES, so a group could pass the 64 MiB it is documented to stay
within by its last image, which can itself be up to 64 MiB (an image
that shares has at most 2^26 pixels, and as its rows are whole bytes,
at most that many bytes; a 1-pixel-wide one takes them all). hold_in
codes the group first when an image would take it past the limit, and
after when it has 16 images; with room for 10 bytes, images of 4 go two
to a group, where the old order made one of 12. CodeRabbit's follow-up
too: the 18-image test decodes every image and compares it with its
samples, across the boundary between the groups.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AmsdeUCdTaD72jkDw2pJKY
* optimize: count the globals' object framing; filters: test the shared coder's size limit
- A JBIG2 group shares a dictionary only when it saves more than the
globals' dictionary and data plus NEW_OBJECT (96 bytes: the object's
framing, its xref entry, and an encrypted file's IV and padding), so a
group that saves less than that no longer makes the file larger.
- encode_jbig2_shared is Unsupported for an image taller than the
decoder takes and codes one at the bound.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* filters: drop the unused rows binding in encode_shared
page() no longer takes the rows since #5511.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* filters: the shared coder's at-bound test says what it returns
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
---------
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
Co-authored-by: FredApps <153173854+FredApps@users.noreply.github.com>
* fix(optimize): make pictures under a stencil mask smaller
An image with any /Mask was skipped by the colour and grey settings. That is
right for a colour-key mask, which names sample values that resampling and JPEG
would change. A stencil mask is an image of its own, with its own resolution
(ISO 32000-2 8.9.6.3), so the picture can change under it and the mask stays as
it is. Some exporters put one on every picture, even where it hides nothing, so
whole drawing sets of pictures were left at full size.
A mask that can't be read as a stencil, such as a reference to nothing, still
leaves its picture alone.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* fix(optimize): only a mask that says /ImageMask true counts as a stencil
A stream /Mask without /ImageMask true let its picture be replaced, although a
mask that isn't a stencil is meant to leave its picture alone. It now does.
The stencil test also checks that the hole still shows what's behind it. The first
pixel all round is left out, because the coarser picture blends into it a little
(at most 26 of 255 in this test).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* test(optimize): draw a coloured page behind the stencil test's picture
On a white page, a hole painted white looks the same as an open hole, so the check
on the hole couldn't tell them apart.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
---------
Co-authored-by: quincy-jc <184324679+quincy-jc@users.noreply.github.com>
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
The image allowance charged a Flate stage the bytes it made, and its input
only as what the stage before it made. Inflating does work for every block it
reads, whether or not the block makes anything: a stream of empty
fixed-Huffman blocks, ten bits each, took 1,383 ns a byte to make nothing
(miniz_oxide 0.9.1, release), one of a literal each 768 ns a byte, empty
dynamic blocks 106, against the 3 ns a step budget.rs states. A 250-byte
stream of four Flates over empty blocks took 47 s and was charged about
34 million steps, so a review of #5698 worked out about 7 hours before a
240 KB file of them was refused, through clearing, Optimize, export, compare
and redaction's images and dictionaries alike.
Where decoding is paid for (decode_tolerant_within, decode_within), a Flate
stage now pays FLATE_READ_WORK, 128 steps, for each byte it reads, before it
runs: a stage the allowance can't pay for doesn't start. Per byte read, the
worst of the shapes measured comes to about 11 ns a step at that price, inside
what a JBIG2 step takes. The raw retry of a zlib header that only looked valid reads the
bytes again, so it pays again, makes no more than is left once it has, and is
refused when it can't be paid for. Byte counts for a byte allowance
(decode_counted, decode_tolerant_counted, as a page's content uses) are
unchanged.
With a tiny file's allowance (2^34 steps), the 250-byte stream is decoded
three times in 141 s, and the fourth stops before its last stage reads the
empty blocks (8.2 ns a step, release). Data an encoder makes took 0.4 to 3.2 ns a byte it
made, reading included, and each byte of a file adds 64 times the price to an
operation's allowance.
Tests: a_flate_stage_pays_for_what_it_reads (empty blocks: 129 steps a byte,
refused a step short with nothing inflated) and a_second_reading_is_paid_for;
the exact costs in filters, cos and optimize tests add what Flate reads.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AmsdeUCdTaD72jkDw2pJKY
`ImageBudget::decode` is now the one public way to decode an image's
CCITT fax or JBIG2 data: `Document::decoded_image` and
`decoded_image_within`, which decoded with no limit on the work, are
test-only in pdfcraft-cos, and pdfcraft-filters exports only
`decode_ccitt_within` and `decode_jbig2_within`, which spend from a
caller's allowance (`decode_jbig2` is gone, `decode_ccitt` private).
So an operation over many images can't decode them without sharing an
allowance; the compiler holds new callers to it. Doctests that must not
compile check both crates; with the old entry points public they fail.
Tests outside the crates decode through an unlimited ImageBudget.
Streams in general (`Stream::decoded`) are left for a follow-up.
Every colour operator in the pages' content and the Form XObjects it draws is
rewritten in the target space by the standard device formulas, source colours
read through the space in force (edit/src/colour.rs: device, ICCBased, CalRGB/
CalGray, Lab, Indexed, Separation/DeviceN through a Type 2 tint). Preserve black,
pictures too (optimize::recolour_image: 8-bit gray/RGB re-encoded, JPEG stays
JPEG, CMYK lossless), comments' and fields' appearances optionally.
Edit::ConvertColours (one undo step; refuses when nothing changes, so
Session::count_colours counts first), the Convert colours dialog, command
prepress.convert_colors, tool doc_convert_colours, rows in every language
(RGB and CMYK allowed unchanged in the Ukrainian and Kazakh checks), parity
print.convert-colors shipped.
Carries the review fixes:
- ATTRIBUTION.toml: the language files' checksums after the new rows
- Convert colours: keep RGB and CMYK as-is in the Czech and Turkish menu-label checks
- Convert colours: CMYK black start, shared objects copied, streams kept apart, guarded count
- Convert colours tests: drop an unused helper
- Format with rustfmt
- i18n(ui): carry this PR's new wordings in the catalogues that must cover them
- Parity: evidence paths follow the tests moved into tests/it
- fix(colours): comment permission for appearances; page range per document
- fix(convert-colours): say what it is not, and what it leaves behind
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
The shapes in these tests all ran one way. The way round depends on the shapes: 1 × 100,000 to
100,000 × 1 asks for 10 GB if it goes across first, or 30 GB at three components, so that is held to
as well. A mask of its image's size comes through byte for byte, and a larger one scales.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AmsdeUCdTaD72jkDw2pJKY
Scaling goes down first, through a buffer of the source's width by the target's
height at 16 bytes a pixel, and neither image's size limit bounds that product.
A soft mask of 60,000 × 1 on an image of 1 × 60,000, about a kilobyte of PDF,
asked for 57 GB and aborted the process, in image export, Office export, Copy
Image and Optimize at its default settings. The same shapes in smaller sizes
held gigabytes.
Such a picture is scaled across first, which holds no more pixels than one of
the two has, so the size limits bound it after all. Proportions that aren't
far apart scale as they did, to the byte.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AmsdeUCdTaD72jkDw2pJKY
Reading a JPEG's header was free, and it can be most of the file: a mask of
1 MiB of tables that disagreed with its dictionary, shared by 4,000 images,
took 101 s with none refused, and that time grows as the square of the file.
A JPEG now pays 4 steps a byte before its tables are parsed, on every path, and
a mask's header is read once. That is a bound and not a speed-up: the same
file of 4,000 images fits the allowance and still takes 97 s, and 12,000 stop
after 10,233 in 250 s.
A chain that can't run pays nothing for its pixels, and the docs say what past
the allowance isn't counted: LZW streams the image pass didn't read.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AmsdeUCdTaD72jkDw2pJKY
Four ways round the allowance, each measured by a review of hostile input:
A Flate stream read as zlib that fails at once, and then as raw deflate that
decodes everything before failing, gave nothing back and so was charged
nothing, here and in DecodeBudget: 110 s for a 387 KB file, all decoded. What
the retry decoded now counts, though the data is still dropped as it was.
Fax and 1-bit Flate images paid by the byte for work done by the pixel: 19
bytes can be a blank page of 100 million pixels, about a second each. Every
image decoded here now pays for its pixels first, as JBIG2 already did.
A JPEG paid nothing, and what one asks for doesn't grow with its length: 156
bytes declared 80 megapixels, 72 s for an 8 KB file. A JPEG pays for its
samples before it is decoded, in Optimize and in an export that has to decode
one for its mask.
Merging fragments paid for reading strips and not for the picture it built:
393 s for 1,154 bytes. It pays for the picture before allocating it.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AmsdeUCdTaD72jkDw2pJKY
Storing LZW streams with Flate decoded image streams outside the allowance,
with a limit for each stream and no total, and nothing asked whether to go
on: a 593 KB file of 100 images took 113 s with none refused, and images
refused by the image pass were still rewritten. The pass now pays for what
it decodes and for storing and checking it, at 8 steps a byte since Flate
takes up to 78 ns a byte, and streams past that stay LZW.
An image is counted as refused only when it stayed as it was: one packed
before the allowance ran out on its second read was rewritten. doc_reduce
reports images_refused as doc_optimize does, and the app's action says so
in its log. A refused image no longer reads as an unsupported filter:
FilterError::Spent says what happened.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AmsdeUCdTaD72jkDw2pJKY
Filters were charged only for what they handed a JBIG2 decoder, once they
had handed it over: a chain that failed, or went past its image's limit,
cost its time and nothing else, and images that weren't JBIG2 weren't
charged at all. A 734 KB file of 200 images of Flate inside Flate took an
image export 111 s, and that grew with the file. It now takes 12 s.
Each byte read and each byte a stage decodes is now a step of the same
allowance, paid as it happens, so no stage runs past what is left. That
holds for every image read through ImageBudget, and a fax image pays for
its rows and its code. JBIG2 globals pay when they have to be read, and
kept ones don't. Optimize's two reads that went round the budget go
through it, and merging fragments shares it.
Optimize reads an image twice, to pack it and to resample it, so a refused
image is now counted once a run rather than once a read.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AmsdeUCdTaD72jkDw2pJKY
Redaction checked the raw /Filter array, so /Crypt in a chain removed an image it could have cleared,
though decoding leaves /Crypt out. It leaves it out too.
Decoded only to be resampled, an image that can't be averaged came to None after the decode, having
spent the run's allowance and perhaps been counted as refused. Each such case now stops before it.
Found by CodeRabbit.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AmsdeUCdTaD72jkDw2pJKY
bflatastic