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| 1 | +# -*- encoding: utf-8 -*- |
| 2 | +# @Author: SWHL |
| 3 | +# @Contact: liekkaskono@163.com |
| 4 | +from io import BytesIO |
| 5 | +from pathlib import Path |
| 6 | +from typing import Any, Union |
| 7 | + |
| 8 | +import cv2 |
| 9 | +import numpy as np |
| 10 | +import requests |
| 11 | +from PIL import Image, UnidentifiedImageError |
| 12 | + |
| 13 | +from .utils import is_url |
| 14 | + |
| 15 | +root_dir = Path(__file__).resolve().parent |
| 16 | +InputType = Union[str, np.ndarray, bytes, Path, Image.Image] |
| 17 | + |
| 18 | + |
| 19 | +class LoadImage: |
| 20 | + def __init__(self): |
| 21 | + pass |
| 22 | + |
| 23 | + def __call__(self, img: InputType) -> np.ndarray: |
| 24 | + if not isinstance(img, InputType.__args__): |
| 25 | + raise LoadImageError( |
| 26 | + f"The img type {type(img)} does not in {InputType.__args__}" |
| 27 | + ) |
| 28 | + |
| 29 | + origin_img_type = type(img) |
| 30 | + img = self.load_img(img) |
| 31 | + img = self.convert_img(img, origin_img_type) |
| 32 | + return img |
| 33 | + |
| 34 | + def load_img(self, img: InputType) -> np.ndarray: |
| 35 | + if isinstance(img, (str, Path)): |
| 36 | + if is_url(img): |
| 37 | + img = Image.open(requests.get(img, stream=True, timeout=60).raw) |
| 38 | + else: |
| 39 | + self.verify_exist(img) |
| 40 | + img = Image.open(img) |
| 41 | + |
| 42 | + try: |
| 43 | + img = self.img_to_ndarray(img) |
| 44 | + except UnidentifiedImageError as e: |
| 45 | + raise LoadImageError(f"cannot identify image file {img}") from e |
| 46 | + return img |
| 47 | + |
| 48 | + if isinstance(img, bytes): |
| 49 | + img = self.img_to_ndarray(Image.open(BytesIO(img))) |
| 50 | + return img |
| 51 | + |
| 52 | + if isinstance(img, np.ndarray): |
| 53 | + return img |
| 54 | + |
| 55 | + if isinstance(img, Image.Image): |
| 56 | + return self.img_to_ndarray(img) |
| 57 | + |
| 58 | + raise LoadImageError(f"{type(img)} is not supported!") |
| 59 | + |
| 60 | + def img_to_ndarray(self, img: Image.Image) -> np.ndarray: |
| 61 | + if img.mode == "1": |
| 62 | + img = img.convert("L") |
| 63 | + return np.array(img) |
| 64 | + return np.array(img) |
| 65 | + |
| 66 | + def convert_img(self, img: np.ndarray, origin_img_type: Any) -> np.ndarray: |
| 67 | + if img.ndim == 2: |
| 68 | + return cv2.cvtColor(img, cv2.COLOR_GRAY2BGR) |
| 69 | + |
| 70 | + if img.ndim == 3: |
| 71 | + channel = img.shape[2] |
| 72 | + if channel == 1: |
| 73 | + return cv2.cvtColor(img, cv2.COLOR_GRAY2BGR) |
| 74 | + |
| 75 | + if channel == 2: |
| 76 | + return self.cvt_two_to_three(img) |
| 77 | + |
| 78 | + if channel == 3: |
| 79 | + if issubclass(origin_img_type, (str, Path, bytes, Image.Image)): |
| 80 | + return cv2.cvtColor(img, cv2.COLOR_RGB2BGR) |
| 81 | + return img |
| 82 | + |
| 83 | + if channel == 4: |
| 84 | + return self.cvt_four_to_three(img) |
| 85 | + |
| 86 | + raise LoadImageError( |
| 87 | + f"The channel({channel}) of the img is not in [1, 2, 3, 4]" |
| 88 | + ) |
| 89 | + |
| 90 | + raise LoadImageError(f"The ndim({img.ndim}) of the img is not in [2, 3]") |
| 91 | + |
| 92 | + @staticmethod |
| 93 | + def cvt_two_to_three(img: np.ndarray) -> np.ndarray: |
| 94 | + """gray + alpha → BGR""" |
| 95 | + img_gray = img[..., 0] |
| 96 | + img_bgr = cv2.cvtColor(img_gray, cv2.COLOR_GRAY2BGR) |
| 97 | + |
| 98 | + img_alpha = img[..., 1] |
| 99 | + not_a = cv2.bitwise_not(img_alpha) |
| 100 | + not_a = cv2.cvtColor(not_a, cv2.COLOR_GRAY2BGR) |
| 101 | + |
| 102 | + new_img = cv2.bitwise_and(img_bgr, img_bgr, mask=img_alpha) |
| 103 | + new_img = cv2.add(new_img, not_a) |
| 104 | + return new_img |
| 105 | + |
| 106 | + @staticmethod |
| 107 | + def cvt_four_to_three(img: np.ndarray) -> np.ndarray: |
| 108 | + """RGBA → BGR""" |
| 109 | + r, g, b, a = cv2.split(img) |
| 110 | + new_img = cv2.merge((b, g, r)) |
| 111 | + |
| 112 | + not_a = cv2.bitwise_not(a) |
| 113 | + not_a = cv2.cvtColor(not_a, cv2.COLOR_GRAY2BGR) |
| 114 | + |
| 115 | + new_img = cv2.bitwise_and(new_img, new_img, mask=a) |
| 116 | + |
| 117 | + mean_color = np.mean(new_img) |
| 118 | + if mean_color <= 0.0: |
| 119 | + new_img = cv2.add(new_img, not_a) |
| 120 | + else: |
| 121 | + new_img = cv2.bitwise_not(new_img) |
| 122 | + return new_img |
| 123 | + |
| 124 | + @staticmethod |
| 125 | + def verify_exist(file_path: Union[str, Path]): |
| 126 | + if not Path(file_path).exists(): |
| 127 | + raise LoadImageError(f"{file_path} does not exist.") |
| 128 | + |
| 129 | + |
| 130 | +class LoadImageError(Exception): |
| 131 | + pass |
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