def point_clouds(flags, data):
    """
    Converts depth maps to point clouds and merges them all into one global point cloud.
    flags: command line arguments
    data: dict with keys ['intrinsics', 'poses']
    returns: [open3d.geometry.PointCloud]
    """
    pcs = []
    intrinsics = get_intrinsics(data['intrinsics'])
    pc = o3d.geometry.PointCloud()
    meshes = []
    rgb_path = os.path.join(flags.path, 'rgb.mp4')
    video = skvideo.io.vreader(rgb_path)
    for i, (T_WC, rgb) in enumerate(zip(data['poses'], video)):
        if i % flags.every != 0:
            continue
        print(f"Point cloud {i}", end="\r")
        T_CW = np.linalg.inv(T_WC)
        confidence = load_confidence(os.path.join(flags.path, 'confidence', f'{i:06}.png'))
        depth_path = data['depth_frames'][i]
        depth = load_depth(depth_path, confidence, filter_level=flags.confidence)
        rgb = Image.fromarray(rgb)
        rgb = rgb.resize((DEPTH_WIDTH, DEPTH_HEIGHT))
        rgb = np.array(rgb)
        rgbd = o3d.geometry.RGBDImage.create_from_color_and_depth(
            o3d.geometry.Image(rgb), depth,
            depth_scale=1.0, depth_trunc=MAX_DEPTH, convert_rgb_to_intensity=False)
        pc += o3d.geometry.PointCloud.create_from_rgbd_image(rgbd, intrinsics, extrinsic=T_CW)
    return [pc]