import numpy as np
from rastervision.core.box import Box
[docs]def fill_overflow(bbox: Box,
window: Box,
chip: np.ndarray,
fill_value: int = 0) -> np.ndarray:
"""Where ``chip``'s ``window`` overflows bbox, fill with ``fill_value``.
Args:
bbox (Box): Bounding box.
window (Box): Window corresponding to the ``chip``.
chip (np.ndarray): (H, W, C) array.
fill_value (int, optional): Value to set overflowing pixels to.
Defaults to 0.
Returns:
np.ndarray: Chip with overflowing regions filled with ``fill_value``.
"""
top_overflow = max(0, bbox.ymin - window.ymin)
bottom_overflow = max(0, window.ymax - bbox.ymax)
left_overflow = max(0, bbox.xmin - window.xmin)
right_overflow = max(0, window.xmax - bbox.xmax)
*_, h, w, _ = chip.shape
ymin, ymax = top_overflow, (h - bottom_overflow)
xmin, xmax = left_overflow, (w - right_overflow)
chip[..., :ymin, :, :] = fill_value
chip[..., ymax:, :, :] = fill_value
chip[..., :, :xmin, :] = fill_value
chip[..., :, xmax:, :] = fill_value
return chip
[docs]def pad_to_window_size(chip: np.ndarray, window: Box, bbox: Box,
fill_value: int) -> np.ndarray:
"""Where chip's window overflows bbox, pad chip with fill_value.
Args:
chip (np.ndarray): (H, W[, C]) array.
bbox (Box): Bounding box.
window (Box): Window corresponding to the ``chip``.
fill_value (int, optional): Value to pad with. Defaults to 0.
Returns:
np.ndarray: Chip of size equal to window size with edges padded with
fill_value where needed.
"""
if window in bbox:
return chip
top_overflow = max(0, bbox.ymin - window.ymin)
bottom_overflow = max(0, window.ymax - bbox.ymax)
left_overflow = max(0, bbox.xmin - window.xmin)
right_overflow = max(0, window.xmax - bbox.xmax)
h, w = window.size
ymin, ymax = top_overflow, (h - bottom_overflow)
xmin, xmax = left_overflow, (w - right_overflow)
if chip.ndim == 2:
out_shape = (h, w)
out = np.full(out_shape, fill_value)
out[ymin:ymax, xmin:xmax] = chip
else:
*dims, _, _, c = chip.shape
out_shape = (*dims, h, w, c)
out = np.full(out_shape, fill_value)
out[..., ymin:ymax, xmin:xmax, :] = chip
return out