OpenCV：使用 warpAffine 旋转地板纹理并保持瓷砖接缝彼此相邻

Question

给定一个正方形或长方形的地砖纹理，如何warpAffine旋转任意角度并保持地砖相邻？（视觉上）

原装地砖

预期结果

4x4 拼接拼贴 + cv2.BORDER_WRAP，拼贴接缝相邻。贴图逆时针旋转了45度，但只有n*pi/2角度当n为奇数

时才能正常工作

瓷砖在视觉上不相交，角度 = 75 度

代码

texture = cv2.imread(ACTIVE_TEXTURE)

def concat_tile(im_list_2d):
    return cv2.vconcat([cv2.hconcat(im_list_h) for im_list_h in im_list_2d])

def rotate_texture(texture, angle=0, scale=1.0):
    print(angle)
    height, width = texture.shape[:2]
    midpoint = (width / 2, height / 2)

    rotation_mat = cv2.getRotationMatrix2D(tuple(midpoint), angle, scale)

    abs_cos = abs(rotation_mat[0, 0])
    abs_sin = abs(rotation_mat[0, 1])

    bound_w = int(height * abs_sin + width * abs_cos)
    bound_h = int(height * abs_cos + width * abs_sin)

    rotation_mat[0, 2] += bound_w / 2 - midpoint[0]
    rotation_mat[1, 2] += bound_h / 2 - midpoint[1]

    texture_rotated = cv2.warpAffine(texture, rotation_mat, (bound_w, bound_h), borderMode=cv2.BORDER_WRAP,
                                     flags=cv2.INTER_AREA)
    texture_rotated = cv2.resize(texture_rotated, (height, width), interpolation=cv2.INTER_AREA)

    return texture_rotated

rot_angle = 45
texture = rotate_texture(texture, angle=rot_angle)
tiles = [[texture for _ in range(4)] for _ in range(4)]
texture = concat_tile(tiles)

cv2.namedWindow('image', cv2.WINDOW_GUI_NORMAL)
cv2.resizeWindow('image', 600, 600)
cv2.imshow('image', texture)
cv2.waitKey()
cv2.destroyAllWindows()

Answer 1

让我提出一个解决方法：

创建不旋转的图块，但增大尺寸以允许裁剪
旋转整个图像
裁剪到所需尺寸

OpenCV：使用 warpAffine 旋转地板纹理并保持瓷砖接缝彼此相邻

OpenCV: Rotate floor texture with warpAffine and keep tile seams adjacent to each other

python

algorithm

opencv

image-processing

computational-geometry