107 lines
2.8 KiB
Python

from math import floor
from typing import Tuple
import numpy as np
from .types import Mat
__all__ = ["crop_xywh", "crop_black_edges", "crop_black_edges_grayscale"]
def crop_xywh(mat: Mat, rect: Tuple[int, int, int, int]):
x, y, w, h = rect
return mat[y : y + h, x : x + w]
def is_black_edge(list_of_pixels: Mat, black_pixel=None):
if black_pixel is None:
black_pixel = np.array([0, 0, 0], list_of_pixels.dtype)
pixels = list_of_pixels.reshape([-1, 3])
return np.count_nonzero(np.all(pixels < black_pixel, axis=1)) > floor(
len(pixels) * 0.6
)
def crop_black_edges(screenshot: Mat):
cropped = screenshot.copy()
black_pixel = np.array([50, 50, 50], screenshot.dtype)
height, width = screenshot.shape[:2]
left = 0
right = width
top = 0
bottom = height
for i in range(width):
column = cropped[:, i]
if not is_black_edge(column, black_pixel):
break
left += 1
for i in sorted(range(width), reverse=True):
column = cropped[:, i]
if i <= left + 1 or not is_black_edge(column, black_pixel):
break
right -= 1
for i in range(height):
row = cropped[i]
if not is_black_edge(row, black_pixel):
break
top += 1
for i in sorted(range(height), reverse=True):
row = cropped[i]
if i <= top + 1 or not is_black_edge(row, black_pixel):
break
bottom -= 1
return cropped[top:bottom, left:right]
def is_black_edge_grayscale(
gray_value_list: np.ndarray, black_threshold: int = 50, ratio: float = 0.6
) -> bool:
return (
np.count_nonzero(gray_value_list < black_threshold)
> len(gray_value_list) * ratio
)
def crop_black_edges_grayscale(
img_gray: Mat, black_threshold: int = 50
) -> Tuple[int, int, int, int]:
"""Returns cropped rect"""
height, width = img_gray.shape[:2]
left = 0
right = width
top = 0
bottom = height
for i in range(width):
column = img_gray[:, i]
if not is_black_edge_grayscale(column, black_threshold):
break
left += 1
for i in sorted(range(width), reverse=True):
column = img_gray[:, i]
if i <= left + 1 or not is_black_edge_grayscale(column, black_threshold):
break
right -= 1
for i in range(height):
row = img_gray[i]
if not is_black_edge_grayscale(row, black_threshold):
break
top += 1
for i in sorted(range(height), reverse=True):
row = img_gray[i]
if i <= top + 1 or not is_black_edge_grayscale(row, black_threshold):
break
bottom -= 1
assert right > left, "cropped width > 0"
assert bottom > top, "cropped height > 0"
return (left, top, right - left, bottom - top)