Files
ModelTrainEval/tests/test_classical.py
T
Shaun ZhouandClaude Opus 5 65bc6b2045 feat(boxes): 新增传统 CV 定位方法(--method cv),不依赖分类模型
背景差分:大半径方框均值估背景 → 残差(可选极性)→ 平滑 → 有无判定 → 按峰值归一化,
再交给与 gradcam / shap 同一套 cam_to_boxes 出框。只依赖 numpy。

与归因方法的差别:不需要 --checkpoint,分类器还没训练出来就能先跑一版框,也不受分类
精度影响;类别只能来自目录(--target label);找的是偏离局部背景的区域,而不是模型
据以判断类别的区域,所以对局部目标好、对铺满整图的纹理类给不出有意义的框。

有无缺陷是显式判定的:残差峰值要同时高于绝对对比度下限与噪声水平(MAD 估计)的 15 倍,
否则返回全零图。这条是必需的——实测纯噪声图的"峰值/MAD"稳定在 9 附近(最大 10.9,
几乎与噪声大小无关),有 0.25 对比度黑点时是 25~330;若只按峰值归一化,正常图的噪声
会被拉到 1,满图假框。阈值 15 取在两者之间。

顺带把积分图方框均值从 shap_explain.smooth 提到 engine/classical.box_mean 共用,
避免两处实现各自漂移。

实测:单张 0.011 秒(全量 11k 约 2 分钟);真实薄膜图上框能套住黑点、虫状物与划痕。
已知局限:背景估计在图像边界处对明暗阶跃有响应,贴边的交界可能出假框。

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-09-17 11:03:13 +08:00

138 lines
5.2 KiB
Python

"""传统 CV 的缺陷显著图(背景差分)。"""
import pytest
np = pytest.importorskip("numpy")
from engine.classical import box_mean, defect_saliency, to_gray # noqa: E402
from engine.gradcam import cam_to_boxes # noqa: E402
BOX_KWARGS = {"threshold": 0.4, "min_area_ratio": 0.002, "max_boxes": 1, "peak_ratio": 0.75}
def _image(size=96, level=0.5, seed=0, noise=0.01):
rng = np.random.default_rng(seed)
return np.clip(level + rng.normal(0, noise, (size, size)), 0, 1).astype(np.float32)
def _with_blob(image, center=(30, 70), radius=4, delta=-0.25):
ys, xs = np.ogrid[: image.shape[0], : image.shape[1]]
blob = (ys - center[0]) ** 2 + (xs - center[1]) ** 2 <= radius**2
out = image.copy()
out[blob] = np.clip(out[blob] + delta, 0, 1)
return out
def test_locates_a_dark_spot():
"""黑点应该落在框里,而且框不能大到没有意义。"""
saliency = defect_saliency(_with_blob(_image()))
boxes = cam_to_boxes(saliency, **BOX_KWARGS)
assert len(boxes) == 1
x1, y1, x2, y2 = boxes[0]
assert x1 <= 70 / 96 <= x2 and y1 <= 30 / 96 <= y2 # 覆盖缺陷中心
assert (x2 - x1) * (y2 - y1) < 0.1 # 不到整图的 10%
@pytest.mark.parametrize("noise", [0.005, 0.01, 0.03])
def test_flat_image_gets_no_box(noise):
"""只有噪声的正常图必须出 0 个框,噪声大小不同都要成立。
回归:若只按峰值归一化,噪声峰值会被拉到 1,满图假框;改成先判定有无缺陷。
"""
saliency = defect_saliency(_image(noise=noise, seed=1))
assert not saliency.any()
assert cam_to_boxes(saliency, **BOX_KWARGS) == []
def test_illumination_gradient_is_not_a_defect():
"""大尺度亮度不均(照明、暗角)属于背景,不该被当成缺陷。"""
ramp = np.linspace(0.3, 0.7, 96, dtype=np.float32)
gradient = np.repeat(ramp[None, :], 96, axis=0)
assert cam_to_boxes(defect_saliency(gradient), **BOX_KWARGS) == []
# 同一张图上的黑点仍要找得到
boxes = cam_to_boxes(defect_saliency(_with_blob(gradient)), **BOX_KWARGS)
assert len(boxes) == 1
@pytest.mark.parametrize(
"polarity,delta,expected",
[("dark", -0.25, 1), ("dark", 0.25, 0), ("bright", 0.25, 1), ("bright", -0.25, 0),
("both", -0.25, 1), ("both", 0.25, 1)],
)
def test_polarity_selects_dark_or_bright(polarity, delta, expected):
image = _with_blob(_image(), delta=delta)
saliency = defect_saliency(image, polarity=polarity)
assert len(cam_to_boxes(saliency, **BOX_KWARGS)) == expected
def test_rejects_unknown_polarity():
with pytest.raises(ValueError, match="polarity"):
defect_saliency(_image(), polarity="darker")
def test_output_range_and_shape():
saliency = defect_saliency(_with_blob(_image(size=64)))
assert saliency.shape == (64, 64)
assert saliency.min() >= 0.0 and saliency.max() <= 1.0
def test_accepts_uint8_rgb_and_grayscale():
"""uint8 / 浮点、单通道 / 三通道都要能进来,结果一致。"""
gray = _with_blob(_image())
as_uint8 = (gray * 255).astype(np.uint8)
rgb = np.repeat(as_uint8[..., None], 3, axis=2)
from_float = cam_to_boxes(defect_saliency(gray), **BOX_KWARGS) # noqa: F841
from_uint8 = cam_to_boxes(defect_saliency(as_uint8), **BOX_KWARGS)
from_rgb = cam_to_boxes(defect_saliency(rgb), **BOX_KWARGS)
assert from_uint8 == from_rgb
assert np.allclose(from_float, from_uint8, atol=0.05)
def test_to_gray_rejects_odd_shapes():
with pytest.raises(ValueError, match="HxW"):
to_gray(np.zeros((5,), dtype=np.float32))
def test_default_radius_scales_with_the_image():
"""background_radius=0 时按 min(高,宽)//8 取值。"""
image = _with_blob(_image(size=96), radius=3)
assert np.array_equal(
defect_saliency(image), defect_saliency(image, background_radius=12)
)
def test_faint_defect_is_rejected_by_min_contrast():
"""对比度低于下限的起伏不算缺陷;调低下限就能找出来。"""
faint = _with_blob(_image(noise=0.005), delta=-0.04)
assert cam_to_boxes(defect_saliency(faint), **BOX_KWARGS) == []
assert len(cam_to_boxes(defect_saliency(faint, min_contrast=0.01), **BOX_KWARGS)) == 1
def test_noisy_image_needs_more_contrast():
"""噪声大的图自动要求更高对比度:同一个弱缺陷在干净图上能找到,在噪声图上不算数。"""
weak = -0.05 # 实测比值:σ=0.002 时 109,σ=0.04 时 9.8
assert len(cam_to_boxes(
defect_saliency(_with_blob(_image(noise=0.002), delta=weak), min_contrast=0.01),
**BOX_KWARGS,
)) == 1
assert cam_to_boxes(
defect_saliency(_with_blob(_image(noise=0.04), delta=weak), min_contrast=0.01),
**BOX_KWARGS,
) == []
def test_box_mean_matches_a_naive_average():
rng = np.random.default_rng(3)
array = rng.random((12, 15))
radius = 2
padded = np.pad(array, radius, mode="edge")
expected = np.empty_like(array)
for y in range(array.shape[0]):
for x in range(array.shape[1]):
expected[y, x] = padded[y:y + 2 * radius + 1, x:x + 2 * radius + 1].mean()
assert np.allclose(box_mean(array, radius), expected)
assert np.array_equal(box_mean(array, 0), array) # radius=0 原样返回