opencv 基础

opencv 入门

安装

windows

# conda 不好安装, 故使用 pip
pip install opencv-python
conda install opencv -c conda-forge

linux

sudo apt install python3-opencv

代码提示

• opencv 安装后没有代码提示；
• 将 C:\Users\kxh\miniforge3\envs\gis\Lib\site-packages\cv2\cv2.pyd 文件复制到上级目录即可；

伪彩色合成

def gray_to_pseudo_color(output: str) -> None:
    img = cv2.imread('temporary_img.png')
    img_color = cv2.applyColorMap(img, 9)
    alpha = np.ones(
        (img_color.shape[0], img_color.shape[1], 1), dtype=np.uint8)*255
    img_rgba = np.concatenate((img_color, alpha), axis=2)
    mask = (img != 0)
    mask = mask.astype(np.uint8)
    mask_alpha = mask[:, :, 2].reshape(
        img_color.shape[0], img_color.shape[1], 1)
    mask_rgba = np.concatenate((mask, mask_alpha), axis=2)
    img_color = img_rgba*mask_rgba
    cv2.imwrite(output, img_color)