第三课:Open3D点云数据处理:点云格式转换

1 Open3D点云格式介绍

1.1 xyz

1.2 xyzn

1.3 xyzrgb

1.4 pts

1.5 ply

1.6 pcd

2 点云格式转换

2.1 读取点云数据

​编辑

2.2 pcd转ply

2.3 pcd转xyz

2.4 pcd转xyzrgb

2.5 pcd转pts

1 Open3D点云格式介绍

1.1 xyz

每一行包含 [x y z] ，其中的x, y, z 是三维坐标，坐标之间以空格分隔。

1.2 xyzn

每一行包含[x, y, z, nx, ny, nz], 其中的nx,ny,nz是法向量

1.3 xyzrgb

每一行包含[x, y, z, r, g, b], 其中的r,g,b是范围在[0, 1]的float类型

1.4 pts

第一行为整数，表示点云中的点数。之后每行为点坐标及其属性，可以是[x, y, z, i, r, g, b]，[x, y, z, r, g, b]，[x, y, z, i]或者[x, y, z]格式，i代表反射强度intensity， 其中x、y、z、i为doublel类型，r、g、b是uint8类型 |

比较有特点的是，pts格式的点云，行与行之间以空白行分隔。

下面以[x, y, z, i, r, g, b]类型为例展示

1.5 ply

ply文件能够同时包含点云和网格数据，有binary和ASCII码两种编码类型。更多内容请查看 Polygon File Format，

二进制binary格式

ASCII码格式

1.6 pcd

pcd格式是PCL指定的点云格式，更多内容请查看 Point Cloud Data

同样的，pcd也有binary和ASCII码两种编码。

binary编码

ASCII编码

2 点云格式转换

open3d进行点云格式转换，不涉及数据格式 ，直接保存为想要的类型即可。下面以pcd点云转换为其他格式的点云为例，进行示范。

2.1 读取点云数据

import open3d as o3d import numpy as np print("->正在加载点云... ") pcd = o3d.io.read_point_cloud(r"H:\HTempWK\temp\open3d\pointdata\Armadillo\Armadillo.pcd") print(pcd) print("->正在可视化点云") o3d.visualization.draw_geometries([pcd])

2.2 pcd转ply

import open3d as o3d print("->加载pcd点云...") pcd = o3d.io.read_point_cloud(r"H:\HTempWK\temp\open3d\pointdata\bunny.pcd") print(pcd) print("->正在可视化点云") o3d.visualization.draw_geometries([pcd]) print("\n->保存为binary类型的ply点云...") o3d.io.write_point_cloud("H:/HTempWK/temp/open3d/data/savebunnyBinary.ply", pcd) # 读取保存得二进制点云数据进行展示 pcd_from_file = o3d.io.read_point_cloud("H:/HTempWK/temp/open3d/data/savebunnyBinary.ply") print("->正在可视化保存的点云...") o3d.visualization.draw_geometries([pcd_from_file]) print("\n->保存为ASCII码类型的ply点云...") o3d.io.write_point_cloud("H:/HTempWK/temp/open3d/data/savebunnyASCII.ply", pcd, write_ascii = True) # 读取保存得ASCII码点云数据进行展示 pcd_from_file = o3d.io.read_point_cloud("H:/HTempWK/temp/open3d/data/savebunnyASCII.ply") print("->正在可视化保存的点云...") o3d.visualization.draw_geometries([pcd_from_file])

2.3 pcd转xyz

import open3d as o3d print("->加载pcd点云...") pcd = o3d.io.read_point_cloud(r"H:\HTempWK\temp\open3d\pointdata\bunny.pcd") # 显示点云 o3d.visualization.draw_geometries([pcd]) print("\n->保存xyz点云...") o3d.io.write_point_cloud(r"H:\HTempWK\temp\open3d\pointdata\bunny.xyz", pcd) print("->保存xyz点云完成") # 读取点云进行展示 pcd_from_file = o3d.io.read_point_cloud(r"H:\HTempWK\temp\open3d\pointdata\bunny.xyz") o3d.visualization.draw_geometries([pcd_from_file])

2.4 pcd转xyzrgb

import open3d as o3d import numpy as np pcd_path = r"H:\HTempWK\temp\open3d\pointdata\bunny.pcd" xyzrgb_path = r"H:\HTempWK\temp\open3d\pointdata\bunny.xyzrgb" pcd = o3d.io.read_point_cloud(pcd_path) points = np.asarray(pcd.points) z = points[:, 2] # 归一化到 0~1 z_norm = (z - z.min()) / (z.max() - z.min()) # 蓝 → 红 渐变 colors = np.zeros((len(points), 3)) colors[:, 0] = z_norm # R colors[:, 2] = 1 - z_norm # B pcd.colors = o3d.utility.Vector3dVector(colors) o3d.io.write_point_cloud(xyzrgb_path, pcd, write_ascii=True) pcd_from_file = o3d.io.read_point_cloud(xyzrgb_path) o3d.visualization.draw_geometries([pcd_from_file])

2.5 pcd转pts

import open3d as o3d print("->加载pcd点云...") pcd = o3d.io.read_point_cloud(r"H:\HTempWK\temp\open3d\pointdata\bunny.pcd") print(pcd) print("->正在可视化点云") o3d.visualization.draw_geometries([pcd]) print("\n->保存pts点云...") o3d.io.write_point_cloud(r"H:\HTempWK\temp\open3d\pointdata\bunny.pts", pcd) # 读取pts数据进行展示 pcd_from_file = o3d.io.read_point_cloud(r"H:\HTempWK\temp\open3d\pointdata\bunny.pts") o3d.visualization.draw_geometries([pcd_from_file])