来自：https://github.com/IntelRealSense/librealsense/issues/1231
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import pyrealsense2 as rs
pipeline = rs.pipeline()
pipe_profile = pipeline.start()
frames = pipeline.wait_for_frames()
depth_frame = frames.get_depth_frame()
color_frame = frames.get_color_frame()

Intrinsics & Extrinsics

depth_intrin = depth_frame.profile.as_video_stream_profile().intrinsics
color_intrin = color_frame.profile.as_video_stream_profile().intrinsics
depth_to_color_extrin = depth_frame.profile.get_extrinsics_to(color_frame.profile)

Depth scale - units of the values inside a depth frame, i.e how to convert the value to units of 1 meter

depth_sensor = pipe_profile.get_device().first_depth_sensor()
depth_scale = depth_sensor.get_depth_scale()

Map depth to color

depth_pixel = [240, 320] # Random pixel
depth_point = rs.rs2_deproject_pixel_to_point(depth_intrin, depth_pixel, depth_scale)
color_point = rs.rs2_transform_point_to_point(depth_to_color_extrin, depth_point)
color_pixel = rs.rs2_project_point_to_pixel(color_intrin, color_point)
pipeline.stop()

---

pc = rs.pointcloud()
frames = pipeline.wait_for_frames()
depth = frames.get_depth_frame()
color = frames.get_color_frame()
img_color = np.asanyarray(color.get_data())
img_depth = np.asanyarray(depth.get_data())
pc.map_to(color)
points = pc.calculate(depth)
vtx = np.asanyarray(points.get_vertices())
tex = np.asanyarray(points.get_texture_coordinates())

npy_vtx = np.zeros((len(vtx), 3), float)
for i in range(len(vtx)):
npy_vtx[i][0] = np.float(vtx[i][0])
npy_vtx[i][1] = np.float(vtx[i][1])
npy_vtx[i][2] = np.float(vtx[i][2])

npy_tex = np.zeros((len(tex), 3), float)
for i in range(len(tex)):
npy_tex[i][0] = np.float(tex[i][0])
npy_tex[i][1] = np.float(tex[i][1])