gain_color.py

import cv2
import numpy as np

video_path = "/mnt/prev_nas/qhy/MagicMotion/assets/mask_trajectory/mammoth_rhino.mp4"

cap = cv2.VideoCapture(video_path)
ret, frame = cap.read()
cap.release()
if not ret:
    raise RuntimeError("无法读取第一帧")

# 你给的两个参考颜色（BGR）
pink_bgr = np.array([77, 80, 119], dtype=np.float32)  # #77504D
red_bgr  = np.array([33, 37, 117], dtype=np.float32)  # #752521

# 阈值（可调）：单位是“颜色距离”
T_pink = 30.0
T_red  = 30.0

# 展平计算距离
img = frame.astype(np.float32)
pixels = img.reshape(-1, 3)

# 距参考颜色的 L2 距离
dist_to_pink = np.linalg.norm(pixels - pink_bgr, axis=1)
dist_to_red  = np.linalg.norm(pixels - red_bgr,  axis=1)

pink_mask = (dist_to_pink < T_pink).reshape(frame.shape[:2])
red_mask  = (dist_to_red  < T_red ).reshape(frame.shape[:2])

# 如果有交叉：距离谁近归谁
both = pink_mask & red_mask
if both.any():
    closer_to_pink = dist_to_pink[both.reshape(-1)] <= dist_to_red[both.reshape(-1)]
    # 把 bool 拉回 2D 时处理稍微麻烦一点，简单写法如下：
    pink_idx = np.where(both)
    # 使用 zip 遍历坐标
    i = 0
    for y, x in zip(*pink_idx):
        if closer_to_pink[i]:
            red_mask[y, x] = False
        else:
            pink_mask[y, x] = False
        i += 1

# 可视化看看
vis = np.zeros_like(frame)
vis[pink_mask] = (255, 0, 255)
vis[red_mask]  = (0, 0, 255)

cv2.imwrite("first_frame_bgr_distance.png", vis)
print("已保存: first_frame_bgr_distance.png")