法线图的坐标系转换

乙巳正月廿四日，余察位姿、深度诸图，其制式各异，存法亦殊。尤甚者，法线图所载之向，或南辕北辙，不能相契。遂穷四十八变，逐一试之，终得正解。乃纂其法，录于下方，以资后学，博诸君一哂耳。

import os
import cv2
from itertools import permutations, product


def apply_channel_swap(img, swap_order):
    """
    Apply channel swap to the image based on the given channel swap order.
    swap_order should be a tuple of indices, e.g., (0, 1, 2) means no swap.
    """
    return img[:, :, swap_order]


def invert_channel(img, channel_indices):
    """
    Invert specific channels in the image (255 - value for the given channels).
    channel_indices is a list of channel indices to be inverted (e.g., [0, 1] for R and G).
    """
    img_copy = img.copy()
    for channel in channel_indices:
        img_copy[:, :, channel] = 255 - img_copy[:, :, channel]
    return img_copy


# 读取A组和B组图像
base_path = '/media/Dataset/room'
A_path = os.path.join(base_path, 'normals_from_gm-prepare')
B_path = os.path.join(base_path, 'normals_from_pretrain')
img_name = '00000011.png'
A_img = cv2.imread(os.path.join(A_path, img_name))
B_img = cv2.imread(os.path.join(B_path, img_name))

# 获取所有通道交换组合
swap_orders = list(permutations([0, 1, 2]))

# 获取所有取反操作的组合
invert_combinations = list(product([False, True], repeat=3))  # 对每个通道是否取反

# 保存每种操作组合的结果
output_path = 'output'
os.makedirs(output_path, exist_ok=True)

for swap_order in swap_orders:
    for invert_comb in invert_combinations:
        # 应用通道交换
        swapped_B_img = apply_channel_swap(B_img, swap_order)

        # 根据取反操作选择要取反的通道
        channels_to_invert = [i for i, invert in enumerate(invert_comb) if invert]
        inverted_B_img = invert_channel(swapped_B_img, channels_to_invert)

        # 生成操作名称字符串
        swap_order_str = ''.join(['RGB'[x] for x in swap_order])  # e.g., 'RGB', 'RBG', etc.
        invert_str = ''.join(['1' if invert else '0' for invert in invert_comb])  # e.g., '000', '010', etc.
        adjusted_img_name = f"adjusted_B_{swap_order_str}_invert_{invert_str}.png"

        # 保存调整后的法线图
        cv2.imwrite(os.path.join(output_path, adjusted_img_name), inverted_B_img)
cv2.imwrite(os.path.join(output_path, "A.png"), A_img)