mirror of
https://github.com/wiltodelta/remove-ai-watermarks.git
synced 2026-08-26 23:42:29 +02:00
fix(cli): preserve alpha channel in visible-watermark pipeline
`cv2.imread(..., IMREAD_COLOR)` was silently stripping the alpha channel on RGBA inputs, and `cv2.imwrite` then wrote opaque 3-channel PNGs — so images with transparent backgrounds came back with an opaque-black (or white) background and the sparkle area baked in as a solid blob. Read the source with `IMREAD_UNCHANGED`, keep the alpha plane out of the detection/inpaint path (those still operate on BGR), and rejoin alpha at save time. The detected watermark bbox is also zeroed in the alpha plane so the sparkle region becomes transparent rather than an opaque artifact. Applies to `visible`, `all`, and `batch` modes. RGB-only inputs and JPEG outputs are unaffected.
This commit is contained in:
Rex Lorenzo
@@ -72,6 +72,27 @@ def _mock_invisible_engine():
|
||||
return mock_cls, mock_engine
|
||||
|
||||
|
||||
def _mock_invisible_engine_drops_alpha():
|
||||
"""Mock InvisibleEngine that mimics the real engine's BGR-only output path.
|
||||
|
||||
The real diffusion-based engine reads with cv2.IMREAD_COLOR and writes a
|
||||
3-channel result. This mock simulates that so we can regression-test alpha
|
||||
preservation across the ``all`` pipeline.
|
||||
"""
|
||||
|
||||
def _mock_remove_watermark(image_path, output_path=None, **kwargs):
|
||||
out = output_path or image_path.with_stem(image_path.stem + "_clean")
|
||||
out.parent.mkdir(parents=True, exist_ok=True)
|
||||
bgr = cv2.imread(str(image_path), cv2.IMREAD_COLOR)
|
||||
cv2.imwrite(str(out), bgr)
|
||||
return out
|
||||
|
||||
mock_engine = MagicMock()
|
||||
mock_engine.remove_watermark.side_effect = _mock_remove_watermark
|
||||
mock_cls = MagicMock(return_value=mock_engine)
|
||||
return mock_cls, mock_engine
|
||||
|
||||
|
||||
class TestMainGroup:
|
||||
"""Tests for the top-level CLI group."""
|
||||
|
||||
@@ -144,6 +165,73 @@ class TestVisibleCommand:
|
||||
result = runner.invoke(main, ["visible", "/nonexistent/file.png"])
|
||||
assert result.exit_code != 0
|
||||
|
||||
def test_visible_preserves_rgba_transparency(self, runner, tmp_path):
|
||||
"""Visible removal on an RGBA PNG must keep the alpha channel,
|
||||
not silently flatten the image onto an opaque background.
|
||||
"""
|
||||
rgba = np.zeros((200, 200, 4), dtype=np.uint8)
|
||||
rgba[:, :, :3] = 200 # light grey foreground
|
||||
rgba[50:150, 50:150, 3] = 255 # opaque square in the middle, rest transparent
|
||||
src = tmp_path / "rgba_in.png"
|
||||
cv2.imwrite(str(src), rgba)
|
||||
|
||||
output = tmp_path / "rgba_out.png"
|
||||
result = runner.invoke(
|
||||
main,
|
||||
["visible", str(src), "-o", str(output), "--no-detect"],
|
||||
)
|
||||
|
||||
assert result.exit_code == 0, result.output
|
||||
assert output.exists()
|
||||
|
||||
out = cv2.imread(str(output), cv2.IMREAD_UNCHANGED)
|
||||
assert out.ndim == 3, f"output is not 3D: shape={out.shape}"
|
||||
assert out.shape[2] == 4, f"output is not RGBA: shape={out.shape}"
|
||||
# The transparent corners must remain transparent.
|
||||
assert out[0, 0, 3] == 0
|
||||
assert out[199, 199, 3] == 0
|
||||
# The opaque centre remains opaque (the watermark region default is bottom-right,
|
||||
# which doesn't overlap the centre square at 200x200).
|
||||
assert out[100, 100, 3] == 255
|
||||
|
||||
def test_visible_clears_alpha_in_watermark_region(self, runner, tmp_path):
|
||||
"""When inpainting an RGBA image, the watermark region must be cleared
|
||||
in the alpha channel so the sparkle area becomes transparent, not opaque-black.
|
||||
"""
|
||||
rgba = np.full((200, 200, 4), 255, dtype=np.uint8) # fully opaque white
|
||||
src = tmp_path / "rgba_full.png"
|
||||
cv2.imwrite(str(src), rgba)
|
||||
|
||||
output = tmp_path / "rgba_cleared.png"
|
||||
result = runner.invoke(
|
||||
main,
|
||||
["visible", str(src), "-o", str(output), "--no-detect"],
|
||||
)
|
||||
|
||||
assert result.exit_code == 0, result.output
|
||||
out = cv2.imread(str(output), cv2.IMREAD_UNCHANGED)
|
||||
assert out.shape[2] == 4
|
||||
# Default sparkle position is in the bottom-right; alpha there must be 0.
|
||||
from remove_ai_watermarks.gemini_engine import get_watermark_config
|
||||
|
||||
cfg = get_watermark_config(200, 200)
|
||||
px, py = cfg.get_position(200, 200)
|
||||
size = cfg.logo_size
|
||||
assert out[py + size // 2, px + size // 2, 3] == 0, "alpha in the watermark region was not cleared"
|
||||
|
||||
def test_visible_rgb_input_stays_rgb(self, runner, sample_png, tmp_path):
|
||||
"""Regression: a plain RGB PNG must NOT gain a spurious alpha channel."""
|
||||
output = tmp_path / "rgb_out.png"
|
||||
result = runner.invoke(
|
||||
main,
|
||||
["visible", str(sample_png), "-o", str(output), "--no-detect"],
|
||||
)
|
||||
|
||||
assert result.exit_code == 0, result.output
|
||||
out = cv2.imread(str(output), cv2.IMREAD_UNCHANGED)
|
||||
assert out.ndim == 3, f"output is not 3D: shape={out.shape}"
|
||||
assert out.shape[2] == 3, f"RGB input produced non-RGB output: shape={out.shape}"
|
||||
|
||||
|
||||
class TestInvisibleCommand:
|
||||
"""Tests for the 'invisible' subcommand."""
|
||||
@@ -210,6 +298,33 @@ class TestAllCommand:
|
||||
result = runner.invoke(main, ["all", "/nonexistent/file.png"])
|
||||
assert result.exit_code != 0
|
||||
|
||||
def test_all_preserves_rgba_across_invisible_step(self, runner, tmp_path):
|
||||
"""Regression: ``all`` must keep transparency even when the invisible
|
||||
step writes a 3-channel result (as the real diffusion engine does).
|
||||
"""
|
||||
rgba = np.zeros((200, 200, 4), dtype=np.uint8)
|
||||
rgba[:, :, :3] = 200
|
||||
rgba[50:150, 50:150, 3] = 255 # opaque square; corners transparent
|
||||
src = tmp_path / "rgba_in.png"
|
||||
cv2.imwrite(str(src), rgba)
|
||||
|
||||
output = tmp_path / "rgba_out.png"
|
||||
mock_cls, _engine = _mock_invisible_engine_drops_alpha()
|
||||
with (
|
||||
patch("remove_ai_watermarks.cli.InvisibleEngine", mock_cls, create=True),
|
||||
patch("remove_ai_watermarks.invisible_engine.InvisibleEngine", mock_cls),
|
||||
patch("remove_ai_watermarks.cli.invisible_available", return_value=True, create=True),
|
||||
patch("remove_ai_watermarks.invisible_engine.is_available", return_value=True),
|
||||
):
|
||||
result = runner.invoke(main, ["all", str(src), "-o", str(output)])
|
||||
|
||||
assert result.exit_code == 0, result.output
|
||||
out = cv2.imread(str(output), cv2.IMREAD_UNCHANGED)
|
||||
assert out.ndim == 3, f"output not 3D: shape={out.shape}"
|
||||
assert out.shape[2] == 4, f"output is not RGBA: shape={out.shape}"
|
||||
assert out[0, 0, 3] == 0
|
||||
assert out[100, 100, 3] == 255
|
||||
|
||||
|
||||
class TestMetadataCommand:
|
||||
"""Tests for the 'metadata' subcommand."""
|
||||
@@ -350,6 +465,37 @@ class TestBatchCommand:
|
||||
assert result.exit_code == 0, result.output
|
||||
assert "3 processed" in result.output
|
||||
|
||||
def test_batch_all_mode_preserves_rgba(self, runner, tmp_path):
|
||||
"""Regression: batch ``all`` must keep transparency across the
|
||||
alpha-dropping invisible step (mirrors test_all_preserves_rgba_...).
|
||||
"""
|
||||
input_dir = tmp_path / "input"
|
||||
input_dir.mkdir()
|
||||
rgba = np.zeros((200, 200, 4), dtype=np.uint8)
|
||||
rgba[:, :, :3] = 200
|
||||
rgba[50:150, 50:150, 3] = 255
|
||||
cv2.imwrite(str(input_dir / "rgba.png"), rgba)
|
||||
|
||||
output_dir = tmp_path / "output"
|
||||
mock_cls, _engine = _mock_invisible_engine_drops_alpha()
|
||||
with (
|
||||
patch("remove_ai_watermarks.cli.InvisibleEngine", mock_cls, create=True),
|
||||
patch("remove_ai_watermarks.invisible_engine.InvisibleEngine", mock_cls),
|
||||
patch("remove_ai_watermarks.cli.invisible_available", return_value=True, create=True),
|
||||
patch("remove_ai_watermarks.invisible_engine.is_available", return_value=True),
|
||||
):
|
||||
result = runner.invoke(
|
||||
main,
|
||||
["batch", str(input_dir), "-o", str(output_dir), "--mode", "all"],
|
||||
)
|
||||
assert result.exit_code == 0, result.output
|
||||
|
||||
out = cv2.imread(str(output_dir / "rgba.png"), cv2.IMREAD_UNCHANGED)
|
||||
assert out.ndim == 3, f"output not 3D: shape={out.shape}"
|
||||
assert out.shape[2] == 4, f"output is not RGBA: shape={out.shape}"
|
||||
assert out[0, 0, 3] == 0
|
||||
assert out[100, 100, 3] == 255
|
||||
|
||||
def test_batch_default_output_dir(self, runner, tmp_path):
|
||||
input_dir = _make_batch_dir(tmp_path)
|
||||
result = runner.invoke(
|
||||
|
||||
Reference in New Issue
Block a user