Files
remove-ai-watermarks/tests/test_cli.py
T
Rex Lorenzo d091b9f822 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.
2026-05-25 09:18:39 -07:00

508 lines
20 KiB
Python

"""Tests for the CLI entry point."""
from __future__ import annotations
import json
from typing import TYPE_CHECKING
from unittest.mock import MagicMock, patch
if TYPE_CHECKING:
from pathlib import Path
import cv2
import numpy as np
import pytest
from click.testing import CliRunner
from PIL import Image
from PIL.PngImagePlugin import PngInfo
from remove_ai_watermarks.cli import main
@pytest.fixture
def runner():
return CliRunner()
@pytest.fixture
def sample_png(tmp_path: Path) -> Path:
"""Create a sample PNG for CLI testing."""
img = np.random.randint(0, 255, (200, 200, 3), dtype=np.uint8)
path = tmp_path / "input.png"
cv2.imwrite(str(path), img)
return path
def _make_batch_dir(tmp_path: Path, count: int = 3) -> Path:
"""Create a directory with test images for batch testing."""
input_dir = tmp_path / "input"
input_dir.mkdir()
for i in range(count):
img = np.random.randint(0, 255, (100, 100, 3), dtype=np.uint8)
cv2.imwrite(str(input_dir / f"img_{i}.png"), img)
return input_dir
def _make_batch_dir_with_metadata(tmp_path: Path, count: int = 3) -> Path:
"""Create a directory with PNG images containing AI metadata."""
input_dir = tmp_path / "input"
input_dir.mkdir()
for i in range(count):
img = Image.new("RGB", (64, 64), color=(100 + i, 150, 200))
pnginfo = PngInfo()
pnginfo.add_text("parameters", f"Steps: 20, Sampler: Euler, img_{i}")
pnginfo.add_text("prompt", "a test landscape")
img.save(input_dir / f"img_{i}.png", pnginfo=pnginfo)
return input_dir
def _mock_invisible_engine():
"""Create a mock InvisibleEngine that writes a copy of the input image."""
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)
img = Image.open(image_path)
img.save(out)
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
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."""
def test_help(self, runner):
result = runner.invoke(main, ["--help"])
assert result.exit_code == 0
assert "Remove visible and invisible" in result.output
def test_version(self, runner):
result = runner.invoke(main, ["--version"])
assert result.exit_code == 0
assert "remove-ai-watermarks" in result.output
assert "version" in result.output
def test_no_command_shows_banner(self, runner):
result = runner.invoke(main, [])
assert result.exit_code == 0
assert "Remove-AI-Watermarks" in result.output
class TestVisibleCommand:
"""Tests for the 'visible' subcommand."""
def test_visible_help(self, runner):
result = runner.invoke(main, ["visible", "--help"])
assert result.exit_code == 0
assert "Gemini watermark" in result.output
def test_visible_basic(self, runner, sample_png, tmp_path):
output = tmp_path / "clean.png"
result = runner.invoke(
main,
["visible", str(sample_png), "-o", str(output), "--no-detect"],
)
assert result.exit_code == 0
assert output.exists()
assert "Saved" in result.output
def test_visible_default_output_name(self, runner, sample_png):
result = runner.invoke(main, ["visible", str(sample_png), "--no-detect"])
assert result.exit_code == 0
expected = sample_png.with_stem(sample_png.stem + "_clean")
assert expected.exists()
def test_visible_no_inpaint(self, runner, sample_png, tmp_path):
output = tmp_path / "clean.png"
result = runner.invoke(
main,
[
"visible",
str(sample_png),
"-o",
str(output),
"--no-inpaint",
"--no-detect",
],
)
assert result.exit_code == 0
assert output.exists()
def test_visible_no_detect(self, runner, sample_png, tmp_path):
output = tmp_path / "clean.png"
result = runner.invoke(
main,
["visible", str(sample_png), "-o", str(output), "--no-detect"],
)
assert result.exit_code == 0
def test_visible_nonexistent_file(self, runner):
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."""
def test_invisible_help(self, runner):
result = runner.invoke(main, ["invisible", "--help"])
assert result.exit_code == 0
assert "invisible" in result.output.lower()
def test_invisible_basic(self, runner, sample_png, tmp_path):
mock_cls, mock_engine = _mock_invisible_engine()
output = tmp_path / "clean.png"
with (
patch("remove_ai_watermarks.cli.InvisibleEngine", mock_cls, create=True),
patch("remove_ai_watermarks.invisible_engine.InvisibleEngine", mock_cls),
):
result = runner.invoke(
main,
["invisible", str(sample_png), "-o", str(output)],
)
assert result.exit_code == 0, result.output
assert output.exists()
mock_engine.remove_watermark.assert_called_once()
def test_invisible_default_output(self, runner, sample_png):
mock_cls, _mock_engine = _mock_invisible_engine()
with (
patch("remove_ai_watermarks.cli.InvisibleEngine", mock_cls, create=True),
patch("remove_ai_watermarks.invisible_engine.InvisibleEngine", mock_cls),
):
result = runner.invoke(main, ["invisible", str(sample_png)])
assert result.exit_code == 0, result.output
expected = sample_png.with_stem(sample_png.stem + "_clean")
assert expected.exists()
def test_invisible_nonexistent_file(self, runner):
result = runner.invoke(main, ["invisible", "/nonexistent/file.png"])
assert result.exit_code != 0
class TestAllCommand:
"""Tests for the 'all' subcommand (full pipeline)."""
def test_all_help(self, runner):
result = runner.invoke(main, ["all", "--help"])
assert result.exit_code == 0
assert "visible" in result.output.lower()
def test_all_basic(self, runner, sample_png, tmp_path):
mock_cls, _mock_engine = _mock_invisible_engine()
output = tmp_path / "clean.png"
with (
patch("remove_ai_watermarks.cli.InvisibleEngine", mock_cls, create=True),
patch("remove_ai_watermarks.invisible_engine.InvisibleEngine", mock_cls),
):
result = runner.invoke(
main,
["all", str(sample_png), "-o", str(output)],
)
assert result.exit_code == 0, result.output
assert output.exists()
def test_all_nonexistent_file(self, runner):
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."""
def test_metadata_help(self, runner):
result = runner.invoke(main, ["metadata", "--help"])
assert result.exit_code == 0
def test_metadata_check_clean(self, runner, tmp_clean_png):
result = runner.invoke(main, ["metadata", str(tmp_clean_png), "--check"])
assert result.exit_code == 0
assert "No AI metadata" in result.output
def test_metadata_check_ai(self, runner, tmp_png_with_ai_metadata):
result = runner.invoke(main, ["metadata", str(tmp_png_with_ai_metadata), "--check"])
assert result.exit_code == 0
assert "AI metadata detected" in result.output
def test_metadata_remove(self, runner, tmp_png_with_ai_metadata, tmp_path):
output = tmp_path / "stripped.png"
result = runner.invoke(
main,
[
"metadata",
str(tmp_png_with_ai_metadata),
"--remove",
"-o",
str(output),
],
)
assert result.exit_code == 0
assert "stripped" in result.output
class TestIdentifyCommand:
"""Tests for the 'identify' subcommand."""
def test_identify_help(self, runner):
result = runner.invoke(main, ["identify", "--help"])
assert result.exit_code == 0
def test_identify_clean_png(self, runner, tmp_clean_png):
result = runner.invoke(main, ["identify", str(tmp_clean_png), "--no-visible"])
assert result.exit_code == 0
assert "unknown" in result.output
def test_identify_ai_png_reports_platform(self, runner, tmp_png_with_ai_metadata):
result = runner.invoke(main, ["identify", str(tmp_png_with_ai_metadata), "--no-visible"])
assert result.exit_code == 0
assert "AI-generated" in result.output
assert "Stable Diffusion" in result.output
def test_identify_json_is_valid(self, runner, tmp_png_with_ai_metadata):
result = runner.invoke(main, ["identify", str(tmp_png_with_ai_metadata), "--no-visible", "--json"])
assert result.exit_code == 0
payload = json.loads(result.output)
assert payload["is_ai_generated"] is True
assert payload["confidence"] == "high"
def test_identify_nonexistent_file(self, runner):
result = runner.invoke(main, ["identify", "/nonexistent/file.png"])
assert result.exit_code != 0
class TestBatchCommand:
"""Tests for the 'batch' subcommand."""
def test_batch_help(self, runner):
result = runner.invoke(main, ["batch", "--help"])
assert result.exit_code == 0
def test_batch_empty_dir(self, runner, tmp_path):
empty_dir = tmp_path / "empty"
empty_dir.mkdir()
result = runner.invoke(main, ["batch", str(empty_dir)])
assert result.exit_code == 0
assert "No supported images" in result.output
def test_batch_visible_mode(self, runner, tmp_path):
input_dir = _make_batch_dir(tmp_path)
output_dir = tmp_path / "output"
result = runner.invoke(
main,
["batch", str(input_dir), "-o", str(output_dir), "--mode", "visible"],
)
assert result.exit_code == 0
assert "3 processed" in result.output
assert output_dir.exists()
assert len(list(output_dir.glob("*.png"))) == 3
def test_batch_metadata_mode(self, runner, tmp_path):
input_dir = _make_batch_dir_with_metadata(tmp_path)
output_dir = tmp_path / "output"
result = runner.invoke(
main,
["batch", str(input_dir), "-o", str(output_dir), "--mode", "metadata"],
)
assert result.exit_code == 0
assert "3 processed" in result.output
assert output_dir.exists()
assert len(list(output_dir.glob("*.png"))) == 3
# Verify AI metadata was stripped
for out_img in output_dir.glob("*.png"):
with Image.open(out_img) as img:
assert "parameters" not in img.info
def test_batch_invisible_mode(self, runner, tmp_path):
input_dir = _make_batch_dir(tmp_path)
output_dir = tmp_path / "output"
mock_cls, _mock_engine = _mock_invisible_engine()
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", "invisible"],
)
assert result.exit_code == 0, result.output
assert "3 processed" in result.output
def test_batch_all_mode(self, runner, tmp_path):
input_dir = _make_batch_dir(tmp_path)
output_dir = tmp_path / "output"
mock_cls, _mock_engine = _mock_invisible_engine()
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
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(
main,
["batch", str(input_dir), "--mode", "visible"],
)
assert result.exit_code == 0
expected_dir = tmp_path / "input_clean"
assert expected_dir.exists()