def test_window_class_toslices():
"""Test Window.toslices"""
window = Window(row_off=0, col_off=1, num_rows=100, num_cols=200)
yslice, xslice = window.toslices()
assert yslice.start == 0
assert yslice.stop == 100
assert xslice.start == 1
assert xslice.stop == 201
def test_window_class_toslices():
"""Test Window.toslices"""
window = Window(row_off=0, col_off=1, num_rows=100, num_cols=200)
yslice, xslice = window.toslices()
assert yslice.start == 0
assert yslice.stop == 100
assert xslice.start == 1
assert xslice.stop == 201
def make_windows_iterator(image_size, window_size, valid_pixels,
validity_threshold):
"""Iterates of patch windows corresponding to valid pixel positions
Args:
image_size (tuple[int]): (height, width) in pixels
window_size (tuple[int]): (window_height, window_width) in pixels
valid_pixels (np.ndarray): (height, width) boolean array
validity_threshold (float): percentage of valid pixels in a window to be considered valid
Yields:
type: rasterio.windows.Window
"""
# Make full raster window object
height, width = image_size
full_image_window = Window(col_off=0,
row_off=0,
width=width,
height=height)
# Create offsets range to iterate on
window_height, window_width = window_size
col_row_offsets = product(range(0, width, window_width),
range(0, height, window_height))
for window_idx, (col_offset, row_offset) in enumerate(col_row_offsets):
# Create window instance
window = Window(col_off=col_offset,
row_off=row_offset,
width=window_width,
height=window_height)
# Verify the window is valid
window_valid_pixels = valid_pixels[window.toslices()]
is_valid = window_valid_pixels.sum(
) / window_valid_pixels.size > validity_threshold
if not is_valid:
continue
# Intersect and return window
window = window.intersection(full_image_window)
yield window_idx, window
