85 lines
2.3 KiB
Python
85 lines
2.3 KiB
Python
import os
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import cv2
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import numpy as np
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def process_png(file_path, output_folder):
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image = cv2.imread(file_path, cv2.IMREAD_UNCHANGED)
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if image is None:
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print(f"无法读取图像：{file_path}")
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return
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if image.shape[2] < 4:
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print(f"图像没有 alpha 通道：{file_path}")
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return
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alpha = image[:, :, 3]
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_, thresh = cv2.threshold(alpha, 0, 255, cv2.THRESH_BINARY)
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contours, _ = cv2.findContours(thresh, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)
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if not contours:
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print(f"图像中没有非透明部分：{file_path}")
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return
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cnt = max(contours, key=cv2.contourArea)
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rect = cv2.minAreaRect(cnt)
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box = cv2.boxPoints(rect)
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box = np.int32(box)
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# 提取最小矩形内的图像并旋转
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width = int(rect[1][0])
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height = int(rect[1][1])
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if width == 0 or height == 0:
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print(f"最小矩形的宽度或高度为零：{file_path}")
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return
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src_pts = box.astype("float32")
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# 定义目标点为水平矩形
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dst_pts = np.array([
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[0, height - 1],
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[0, 0],
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[width - 1, 0],
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[width - 1, height - 1]
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], dtype="float32")
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# 计算透视变换矩阵
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M = cv2.getPerspectiveTransform(src_pts, dst_pts)
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warped = cv2.warpPerspective(image, M, (width, height))
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base, ext = os.path.splitext(os.path.basename(file_path))
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extracted_filename = f"{base}_extracted{ext}"
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extracted_path = os.path.join(output_folder, extracted_filename)
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# 保存带 alpha 通道的图像
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if warped.shape[2] == 4:
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cv2.imwrite(extracted_path, warped)
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else:
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# 如果没有 alpha 通道，转换为 RGB
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cv2.imwrite(extracted_path, cv2.cvtColor(warped, cv2.COLOR_BGR2RGB))
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print(f"提取并旋转后的图像已保存为：{extracted_path}")
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def main():
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input_folder = 'output'
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output_folder = 'output2'
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if not os.path.exists(output_folder):
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os.makedirs(output_folder)
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png_files = [f for f in os.listdir(input_folder) if f.lower().endswith('.png')]
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if not png_files:
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print("在指定的文件夹中未找到 PNG 文件。")
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return
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for filename in png_files:
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file_path = os.path.join(input_folder, filename)
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print(f"正在处理文件：{file_path}")
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process_png(file_path, output_folder)
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if __name__ == "__main__":
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main()
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