Femto Mega's output topic timestamp is wrong

[Kanazawanaoaki]

We are using Femto Mega with the latest main branch
OrbbecSDK_ROS1, but the timestamp of the output ros topic was incorrect.

$ roslaunch orbbec_camera femto_mega.launch color_fps:=15 depth_fps:=15 enable_colored_point_cloud:=true depth_registration:=true camera_name:=femto_meg
$ rostopic echo /femto_mega/color/image_raw --noarr -n1
header: 
  seq: 0
  stamp: 
    secs: 1623747315
    nsecs:  12999936
  frame_id: "femto_mega_color_optical_frame"
height: 720
width: 1280
encoding: "rgb8"
is_bigendian: 0
step: 3840
data: "<array type: uint8, length: 2764800>"
---

(1623747315 = Tue Jun 15 2021 08:55:15 GMT+0000)

I think the reason for this is that the rosparam of the default use_hardware_time is set to true in the following part.

OrbbecSDK_ROS1/src/ob_camera_node.cpp

Line 149 in b49127f

use_hardware_time_ = nh_private_.param<bool>("use_hardware_time", true);

If we change femto_mega.launch and set the rosparam of use_hardware_time to false, the system timestamp will be used and the desired behavior will be achieved.

$ rostopic echo /femto_mega/color/image_raw --noarr -n1
header: 
  seq: 11
  stamp: 
    secs: 1732250614
    nsecs: 391756032
  frame_id: "femto_mega_color_optical_frame"
height: 720
width: 1280
encoding: "rgb8"
is_bigendian: 0
step: 3840
data: "<array type: uint8, length: 2764800>"
---

(1732250614 = Fri Nov 22 2024 04:43:34 GMT+0000)

It seems that the arg for use_hardware_time is provided for the launch of some cameras that use hardware time, such as femto bolt, so it would be better to either change the default for use_hardware_time rosparam to false, or add the arg for use_hardware_time to the launch of cameras such as femto_mega (like https://github.com/Kanazawanaoaki/OrbbecSDK_ROS1/tree/add-use_hardware_time-to-femto-mega ).

[3Ddaiwei]

Thank you for your question and suggestion. When the configuration "use_hardware_time" is set to false, the system timestamp will be used. When it is set to true, the device timestamp will be used. Regarding your question, we will double-check and optimize it.