Spaces:
Build error
Build error
import random | |
import math | |
from typing import Any | |
import numpy as np | |
""" | |
Code adapted from beit mask generator: https://github.com/microsoft/unilm/blob/ecff36188001e9b12a90b01bbbaf9058d2b8bda6/beit/masking_generator.py . | |
""" | |
__all__ = ["MaskGenerator"] | |
class MaskGenerator: | |
def __init__( | |
self, | |
input_size: int, | |
num_mask_patches: int, | |
min_num_patches: int = 4, | |
max_num_patches: int = None, | |
min_aspect: float = 0.3, | |
max_aspect: float = None, | |
) -> None: | |
if not isinstance(input_size, tuple): | |
input_size = (input_size,) * 2 | |
self.height, self.width = input_size | |
self.num_patches = self.height * self.width | |
self.num_mask_patches = num_mask_patches | |
self.min_num_patches = min_num_patches | |
self.max_num_patches = ( | |
num_mask_patches if max_num_patches is None else max_num_patches | |
) | |
max_aspect = max_aspect or 1 / min_aspect | |
self.log_aspect_ratio = (math.log(min_aspect), math.log(max_aspect)) | |
def __repr__(self): | |
repr_str = "Generator(%d, %d -> [%d ~ %d], max = %d, %.3f ~ %.3f)" % ( | |
self.height, | |
self.width, | |
self.min_num_patches, | |
self.max_num_patches, | |
self.num_mask_patches, | |
self.log_aspect_ratio[0], | |
self.log_aspect_ratio[1], | |
) | |
return repr_str | |
def get_shape(self): | |
return self.height, self.width | |
def _mask(self, mask: np.array, max_mask_patches: int) -> int: | |
delta = 0 | |
for _ in range(10): | |
target_area = random.uniform(self.min_num_patches, max_mask_patches) | |
aspect_ratio = math.exp(random.uniform(*self.log_aspect_ratio)) | |
h = int(round(math.sqrt(target_area * aspect_ratio))) | |
w = int(round(math.sqrt(target_area / aspect_ratio))) | |
if w < self.width and h < self.height: | |
top = random.randint(0, self.height - h) | |
left = random.randint(0, self.width - w) | |
num_masked = mask[top : top + h, left : left + w].sum() | |
if 0 < h * w - num_masked <= max_mask_patches: | |
for i in range(top, top + h): | |
for j in range(left, left + w): | |
if mask[i, j] == 0: | |
mask[i, j] = 1 | |
delta += 1 | |
if delta > 0: | |
break | |
return delta | |
def __call__(self) -> Any: | |
mask = np.zeros((self.height, self.width), dtype=np.int32) | |
mask_count = 0 | |
while mask_count < self.num_mask_patches: | |
max_mask_patches = self.num_mask_patches - mask_count | |
max_mask_patches = min(max_mask_patches, self.max_num_patches) | |
delta = self._mask(mask, max_mask_patches) | |
if delta == 0: | |
break | |
else: | |
mask_count += delta | |
return mask | |
if __name__ == "__main__": | |
mg = MaskGenerator(input_size=14, num_mask_patches=75) | |
mask = mg() | |
print(mask) | |
print(mg, mask.sum()) | |