Skip to content

Improved handling of RGBA palettes when saving GIF images #8494

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

Merged
hugovk merged 1 commit into from
Dec 16, 2024
Merged

Improved handling of RGBA palettes when saving GIF images #8494

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
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
6 changes: 4 additions & 2 deletions Tests/test_file_gif.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -4,6 +4,7 @@
from collections.abc import Generator
from io import BytesIO
from pathlib import Path
from typing import Any

import pytest

Expand Down Expand Up @@ -1431,7 +1432,8 @@ def test_saving_rgba(tmp_path: Path) -> None:
assert reloaded_rgba.load()[0, 0][3] == 0


def test_optimizing_p_rgba(tmp_path: Path) -> None:
@pytest.mark.parametrize("params", ({}, {"disposal": 2, "optimize": False}))
def test_p_rgba(tmp_path: Path, params: dict[str, Any]) -> None:
out = str(tmp_path / "temp.gif")

im1 = Image.new("P", (100, 100))
Expand All @@ -1443,7 +1445,7 @@ def test_optimizing_p_rgba(tmp_path: Path) -> None:
im2 = Image.new("P", (100, 100))
im2.putpalette(data, "RGBA")

im1.save(out, save_all=True, append_images=[im2])
im1.save(out, save_all=True, append_images=[im2], **params)

with Image.open(out) as reloaded:
assert reloaded.n_frames == 2
5 changes: 3 additions & 2 deletions src/PIL/GifImagePlugin.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -695,8 +695,9 @@ def _write_multiple_frames(
)
background = _get_background(im_frame, color)
background_im = Image.new("P", im_frame.size, background)
assert im_frames[0].im.palette is not None
background_im.putpalette(im_frames[0].im.palette)
first_palette = im_frames[0].im.palette
assert first_palette is not None
background_im.putpalette(first_palette, first_palette.mode)
bbox = _getbbox(background_im, im_frame)[1]
elif encoderinfo.get("optimize") and im_frame.mode != "1":
if "transparency" not in encoderinfo:
Expand Down