Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Only read until the offset of the next tile #8609

Open
wants to merge 2 commits into
base: main
Choose a base branch
from
Open

Only read until the offset of the next tile #8609

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
024ed66
Only read until the offset of the next tile
radarhere Dec 19, 2024
41a2003
Merge branch 'main' into tile_read
radarhere Dec 20, 2024
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
20 changes: 20 additions & 0 deletions Tests/test_imagefile.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -118,6 +118,26 @@ def test_safeblock(self) -> None:

assert_image_equal(im1, im2)

def test_tile_size(self) -> None:
with open("Tests/images/hopper.tif", "rb") as im_fp:
data = im_fp.read()

reads = []

class FP(BytesIO):
def read(self, size: int | None = None) -> bytes:
reads.append(size)
return super().read(size)

fp = FP(data)
with Image.open(fp) as im:
assert len(im.tile) == 7

im.load()

# Despite multiple tiles, assert only one tile caused a read of maxblock size
assert reads.count(im.decodermaxblock) == 1

def test_raise_oserror(self) -> None:
with pytest.warns(DeprecationWarning):
with pytest.raises(OSError):
Expand Down
9 changes: 7 additions & 2 deletions src/PIL/ImageFile.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -263,7 +263,7 @@ def load(self) -> Image.core.PixelAccess | None:
self.tile, lambda tile: (tile[0], tile[1], tile[3])
)
]
for decoder_name, extents, offset, args in self.tile:
for i, (decoder_name, extents, offset, args) in enumerate(self.tile):
seek(offset)
decoder = Image._getdecoder(
self.mode, decoder_name, args, self.decoderconfig
Expand All @@ -276,8 +276,13 @@ def load(self) -> Image.core.PixelAccess | None:
else:
b = prefix
while True:
read_bytes = self.decodermaxblock
if i + 1 < len(self.tile):
next_offset = self.tile[i + 1].offset
if next_offset > offset:
read_bytes = next_offset - offset
try:
s = read(self.decodermaxblock)
s = read(read_bytes)
except (IndexError, struct.error) as e:
# truncated png/gif
if LOAD_TRUNCATED_IMAGES:
Expand Down
Loading