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hub / github.com/aigc3d/LHM / Preprocessor

Class Preprocessor

LHM/utils/preprocess.py:21–88  ·  view source on GitHub ↗

Preprocessing under cv2 conventions.

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19
20
21class Preprocessor:
22
23 """
24 Preprocessing under cv2 conventions.
25 """
26
27 def __init__(self):
28 self.rembg_session = rembg.new_session(
29 providers=["CUDAExecutionProvider", "CPUExecutionProvider"],
30 )
31
32 def preprocess(self, image_path: str, save_path: str, rmbg: bool = True, recenter: bool = True, size: int = 512, border_ratio: float = 0.2):
33 image = self.step_load_to_size(image_path=image_path, size=size*2)
34 if rmbg:
35 image = self.step_rembg(image_in=image)
36 else:
37 image = cv2.cvtColor(image, cv2.COLOR_BGR2BGRA)
38 if recenter:
39 image = self.step_recenter(image_in=image, border_ratio=border_ratio, square_size=size)
40 else:
41 image = cv2.resize(
42 src=image,
43 dsize=(size, size),
44 interpolation=cv2.INTER_AREA,
45 )
46 return cv2.imwrite(save_path, image)
47
48 def step_rembg(self, image_in: np.ndarray) -> np.ndarray:
49 image_out = rembg.remove(
50 data=image_in,
51 session=self.rembg_session,
52 )
53 return image_out
54
55 def step_recenter(self, image_in: np.ndarray, border_ratio: float, square_size: int) -> np.ndarray:
56 assert image_in.shape[-1] == 4, "Image to recenter must be RGBA"
57 mask = image_in[..., -1] > 0
58 ijs = np.nonzero(mask)
59 # find bbox
60 i_min, i_max = ijs[0].min(), ijs[0].max()
61 j_min, j_max = ijs[1].min(), ijs[1].max()
62 bbox_height, bbox_width = i_max - i_min, j_max - j_min
63 # recenter and resize
64 desired_size = int(square_size * (1 - border_ratio))
65 scale = desired_size / max(bbox_height, bbox_width)
66 desired_height, desired_width = int(bbox_height * scale), int(bbox_width * scale)
67 desired_i_min, desired_j_min = (square_size - desired_height) // 2, (square_size - desired_width) // 2
68 desired_i_max, desired_j_max = desired_i_min + desired_height, desired_j_min + desired_width
69 # create new image
70 image_out = np.zeros((square_size, square_size, 4), dtype=np.uint8)
71 image_out[desired_i_min:desired_i_max, desired_j_min:desired_j_max] = cv2.resize(
72 src=image_in[i_min:i_max, j_min:j_max],
73 dsize=(desired_width, desired_height),
74 interpolation=cv2.INTER_AREA,
75 )
76 return image_out
77
78 def step_load_to_size(self, image_path: str, size: int) -> np.ndarray:

Callers 3

init_preprocessorFunction · 0.90
init_preprocessorFunction · 0.90
init_preprocessorFunction · 0.90

Calls

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Tested by

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