This is for validating that a decoder with a weak or nonexistent
sniff() method thinks it can decode an image. This should not be
treated as an error.
No behavior change.
...from try_create_for_raw_bytes().
If a plugin returns `true` from sniff but then fails when calling
its `create()` method, we now no longer swallow that error.
Allows `image` (and other places in the system) to print a more
actionable error if early image headers are invalid.
(We now no longer try to find another plugin that can also handle
the image.)
Fixes a regression from #20063 / #19893 -- before then, we didn't
do fallible work this early.
The semantics of BGRx8888 aren't super clear and it means different
things for different parts of the codebase. In particular, the PNG
writer still writes the x channel to the alpha channel of its output.
In BMPs, the 4th palette byte is usually 0, which means after #21412 we
started writing all .bmp files with <= 8bpp as completely transparent
to PNGs.
This works around that.
(See also #19464 for previous similar workarounds.)
The added `bitmap.bmp` is a 1bpp file I drew in Photoshop and saved
using its "Save as..." saving path.
...to avoid allocating a copy of glyph run for painting commands. We
can't simply save pointers to a glyph run in layout/paintable tree
because it should be safe to deallocate layout and paintable trees
after painting commands are recorded, if in the future we decide to
move command execution to a separate thread.
It's like ScaledFont::with_size(), except that it guarantees that the
result is non-null and ScaledFont. (Smart pointers don't allow
covariant return types, else we could just narrow down the return
type of with_size() while still overriding the base method.)
No behavior change.
Some fonts have empty slices for glyphs with 0 contours, even though
the spec requires them to store a 0 for instructionLength as far as
I can tell. But let's not assert on invalid fonts like this, but instead
handle them gracefully.
Supersedes #22570.
Fixes the last two crashes on my 1000-file test set: 0000246.pdf and
0000431.pdf.
This patch brings few small QoL improvements:
- We don't need to read the Huffman stream before returning an error
due to a missing quantization table.
- We check the table presence only once per scan instead of once per
MCU.
- `dequantize()` is now infallible.
The old implementation of PassMode has only been tested with a single
image, and let's say that it didn't survive long in the wild. A few
cases were not considered:
- We only supported VerticalMode right after PassMode.
- It can happen that token need to be used but not consumed from the
reference line.
With that fix, we are able to decode every single PDF file from the
1000-file zip "0000" (except 0000871.pdf, which uses byte alignment).
This is massive progress compared to the hundred of errors that we were
previously receiving.
It turns out that hmtx and OS/2 table values _are_ used when
rendering OpenType for PDFs: hmtx is used for the left-side bearing
value (which is read in `Painter::draw_glyph()`), and OS/2 is used
for the ascender, which Type0's CIDFontType2::draw_glyph()
and TrueTypeFont::draw_glyph() read.
So instead of not trying to read these tables, instead try to read
them but tolerate them failing to read and ignore them then.
Follow-up to #23276.
(I've seen weird glyph positioning from not reading the hmtx table.
I haven't seen any problems caused by not reading the OS/2 table yet,
but since the PDF code does use the ascender value, let's read that
too.)
The former automatically adapts the prefix to binary and octal
output, and is what we already use in the majority of cases.
Patch generated by:
rg -l '0x\{' | xargs sed -i '' -e 's/0x{:/{:#/'
I ran it 4 times (until it stopped changing things) since each
invocation only converted one instance per line.
No behavior change.
Check if we have a cmap before dereferencing it again.
Fixes a crash on page 8 of 0000188.pdf now that the font no
longer fails to load to due to a missing name table.
Looks like this is a Type2 truetype font, where we don't provide
an external cmap. How this font is supposed to work without a cmap
I don't know -- but for now, we no longer crash on it, and draw
some of the text with the previous font (which happens to work
fine in this particular case).
Kind of reverts #21675, but #21744 made that better
4 of my 1000 test PDFs complained "Invalid table offset or length in
font" before.
For example, in 0000203.pdf, these tags had length 0: 'cvt ', 'fpgm',
'prep', 'name', 'OS/2'. (Generally it's tables that aren't needed
for rendering PDFs, and the PDF writer figured it's easier to zero
out these tables instead of omitting them altogether for some reason.)
Increases number of PDFs that render without diagnostics from
765 to 767.
It is sometimes truncated in fonts embedded in PDFs, and the data
is not needed to render PDFs. 2 of my 1000 test PDFs used to
complain "Could not load OS2 v1: Not enough data" and 1
"Could not load OS2 v2: Not enough data" before.
Increases number of PDFs that render without diagnostics from
764 to 765 (and decreases the number of distinct error messages
from 27 to 25).
It is sometimes truncated in fonts embedded in PDFs, and the data
is not needed to render PDFs. 26 of my 1000 test files complained
"Could not load Hmtx: Not enough data" before.
Increases number of PDFs that render without diagnostics from
743 to 764.
It is often missing in fonts embedded in PDFs. 75 of my 1000 test
files complained "Font is missing Name" when trying to read fonts
before.
Increases number of PDFs that render without diagnostics from
682 to 743.
Before, we used to reject profiles where the creation datetime was
invalid per spec. But invalid dates happen in practice (most commonly,
all fields set to 0). They don't affect profile conversion at all,
so be lenient about this, in exchange for slightly more wordy code
in the places that want to show the creation datetime.
Fixes a crash rendering page 2 of
https://fredrikbk.com/publications/copy-and-patch.pdf
