Feature Request: Support ROS pointclouds from Ouster 128-beam LIDAR

[Chambana]

Ouster's OS0-128 outputs 128 lines of resolution in a standard pointcloud2 msg on the ROS topic, "/os_cloud_node/points". Per the link below, the ROS node assumes the standard Velodyne pointcloud topic and 16/32/64 projections. Feature request is to add support for 128-beam ROS pointclouds on arbitrary topics.

depth_clustering/examples/ros_nodes/save_clusters_node.cpp

Lines 40 to 68 in fe9d667

	int main(int argc, char* argv[]) {
	TCLAP::CmdLine cmd(
	"Subscribe to /velodyne_points topic and save clusters to disc.", ' ',
	"1.0");
	TCLAP::ValueArg<int> angle_arg(
	"", "angle",
	"Threshold angle. Below this value, the objects are separated", false, 10,
	"int");
	TCLAP::ValueArg<int> num_beams_arg(
	"", "num_beams", "Num of vertical beams in laser. One of: [16, 32, 64].",
	true, 0, "int");
	cmd.add(angle_arg);
	cmd.add(num_beams_arg);
	cmd.parse(argc, argv);
	Radians angle_tollerance = Radians::FromDegrees(angle_arg.getValue());
	std::unique_ptr<ProjectionParams> proj_params_ptr = nullptr;
	switch (num_beams_arg.getValue()) {
	case 16:
	proj_params_ptr = ProjectionParams::VLP_16();
	break;
	case 32:
	proj_params_ptr = ProjectionParams::HDL_32();
	break;
	case 64:
	proj_params_ptr = ProjectionParams::HDL_64();
	break;

[niosus]

Thanks for the suggestion! I will not have the time to work on this, but I am happy to review a PR about it.