【Open3D】第一篇：点云的基本操作

参考网址

网址1

读取点云

cloud=o3d.io.read_point_cloud(args.ipath)	# 读取点云
cloud_xyz=np.asarray(cloud.points) 			# 获取点云坐标数据
num_of_pts=len(cloud_xyz)					# 获取点个数

创建和保存点云

pcd = o3d.geometry.PointCloud()
pcd.points = o3d.utility.Vector3dVector(xyz)
o3d.io.write_point_cloud("../../TestData/sync.ply", pcd)

kdtree搜索

import open3d as o3d
import numpy as np

pcd = o3d.io.read_point_cloud("chair.pcd")
# 建立KD树
pcd_tree = o3d.geometry.KDTreeFlann(pcd)
# 使用K近邻，将第1500个点最近的100个点设置为蓝色
k = 100  # 设置K的大小
[nn_k, idx_k, _] = pcd_tree.search_knn_vector_3d(pcd.points[1500], k)  # 返回邻域点的个数和索引

绘制

绘制三角片

import open3d
import numpy as np
mesh = open3d.geometry.TriangleMesh()
np_vertices = np.array([[2, 2, 0],
                        [5, 2, 0],
                        [5, 5, 0]])
np_triangles = np.array([[0, 1, 2]]).astype(np.int32)
mesh.vertices = open3d.utility.Vector3dVector(np_vertices)
mesh.triangles = open3d.utility.Vector3iVector(np_triangles)
open3d.visualization.draw_geometries([mesh])

绘制两个物体

import open3d as o3d
import numpy as np
cloud=o3d.io.read_point_cloud("/home/i9/experiment_nc/church.ply")
cloud_xyz=np.asarray(cloud.points)

print("Let's draw a cubic using o3d.geometry.LineSet.")
points = [
    [0, 0, 0],
    [1, 0, 0],
    [0, 1, 0],
    [1, 1, 0],
    [0, 0, 1],
    [1, 0, 1],
    [0, 1, 1],
    [1, 1, 1],
]
lines = [
    [0, 1],
    [0, 2],
    [1, 3],
    [2, 3],
    [4, 5],
    [4, 6],
    [5, 7],
    [6, 7],
    [0, 4],
    [1, 5],
    [2, 6],
    [3, 7],
]
colors = [[1, 0, 0] for i in range(len(lines))]
object = o3d.geometry.LineSet(
    points=o3d.utility.Vector3dVector(points),
    lines=o3d.utility.Vector2iVector(lines),
)

# o3d.geometry
object.colors = o3d.utility.Vector3dVector(colors)
o3d.visualization.draw_geometries([object, cloud])