Files
remove-ai-watermarks/tests/test_videoseal_oracle.py
T

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4.6 KiB
Python

"""Tests for the pinned VideoSeal TorchScript oracle's pure helpers."""
from __future__ import annotations
import sys
from pathlib import Path
import numpy as np
import pytest
SCRIPTS = Path(__file__).resolve().parents[1] / "scripts"
if str(SCRIPTS) not in sys.path:
sys.path.insert(0, str(SCRIPTS))
import videoseal_oracle # noqa: E402
class TestMessage:
def test_message_is_deterministic_and_256_bits(self) -> None:
first = videoseal_oracle.message_bits()
second = videoseal_oracle.message_bits()
assert first == second
assert len(first) == 256
assert set(first) <= {0, 1}
def test_seed_changes_the_message(self) -> None:
assert videoseal_oracle.message_bits(seed=8) != videoseal_oracle.message_bits(seed=7)
class TestLabel:
def test_label_is_hex_of_the_decoded_bits(self) -> None:
bits = tuple([1] * 8 + [0] * 8)
reading = videoseal_oracle.VideoSealReading(
bit_accuracy=1.0,
decoded_bits=bits,
per_frame_bit_accuracy=(1.0,),
)
assert reading.label == "ff00"
def test_detection_rule_is_the_documented_threshold(self) -> None:
below = videoseal_oracle.VideoSealReading(0.89, (0,), ())
exact = videoseal_oracle.VideoSealReading(0.9, (0,), ())
assert below.detected is False
assert exact.detected is True
class TestPins:
def test_checkpoint_pin_is_a_sha256_digest(self) -> None:
digest = videoseal_oracle.JIT_SHA256
assert len(digest) == 64
assert all(char in "0123456789abcdef" for char in digest)
def test_source_commit_is_pinned(self) -> None:
assert len(videoseal_oracle.SOURCE_COMMIT) == 40
class TestCacheOverride:
def test_cache_dir_env_override_is_honored(self, monkeypatch: pytest.MonkeyPatch, tmp_path: Path) -> None:
original_cache = videoseal_oracle.CACHE_DIR
import importlib
try:
with monkeypatch.context() as environment:
environment.setenv("VIDEOSEAL_CACHE_DIR", str(tmp_path / "cache"))
importlib.reload(videoseal_oracle)
assert tmp_path / "cache" == videoseal_oracle.CACHE_DIR
finally:
importlib.reload(videoseal_oracle)
assert original_cache == videoseal_oracle.CACHE_DIR
class TestAggregationFormulas:
def test_aggregations_match_the_upstream_formulas(self) -> None:
torch = pytest.importorskip("torch")
# Two frames, four bits; hand-computed from the upstream extract_message
# formulas so a silent mutation of the port fails here.
bit_preds = torch.tensor([[2.0, -1.0, 0.5, -3.0], [0.1, 0.2, -0.4, 0.3]])
avg = videoseal_oracle._aggregate_bit_preds(bit_preds, "avg")
squared = videoseal_oracle._aggregate_bit_preds(bit_preds, "squared_avg")
l1 = videoseal_oracle._aggregate_bit_preds(bit_preds, "l1norm_avg")
l2 = videoseal_oracle._aggregate_bit_preds(bit_preds, "l2norm_avg")
torch.testing.assert_close(avg, bit_preds.mean(dim=0))
torch.testing.assert_close(squared, (bit_preds * bit_preds.abs()).mean(dim=0))
w1 = torch.norm(bit_preds, p=1, dim=1).unsqueeze(1)
torch.testing.assert_close(l1, (bit_preds * w1).mean(dim=0))
w2 = torch.norm(bit_preds, p=2, dim=1).unsqueeze(1)
torch.testing.assert_close(l2, (bit_preds * w2).mean(dim=0))
def test_unknown_aggregation_is_rejected(self) -> None:
torch = pytest.importorskip("torch")
with pytest.raises(ValueError, match="unknown aggregation"):
videoseal_oracle._aggregate_bit_preds(torch.zeros(2, 4), "median")
class TestImageMode:
def test_image_helpers_preserve_layout_and_decode_message_columns(self) -> None:
torch = pytest.importorskip("torch")
message = (1, 0, 1, 0)
class Model:
def embed(self, tensor: object, bits: object, *, is_video: bool) -> object:
assert is_video is False
torch.testing.assert_close(bits, torch.tensor([message], dtype=torch.float32))
return tensor
def detect(self, tensor: object, *, is_video: bool) -> object:
assert is_video is False
assert tuple(tensor.shape) == (1, 3, 2, 4)
return {"preds": torch.tensor([[9.0, 1.0, -1.0, 1.0, -1.0]])}
pixels = np.arange(24, dtype=np.float32).reshape(2, 4, 3) / 24.0
marked = videoseal_oracle.embed_image(Model(), pixels, message)
np.testing.assert_allclose(marked, pixels)
assert videoseal_oracle.decode_image(Model(), marked) == message