SR300 has fixed time stamp

[MarqRazz]

System Configuration

Version	Your Configuration
Operating System	Ubuntu 14.04.5 LTS
Kernel	4.4.0-64-generic
ROS	indigo
ROS RealSense	1.7.1
librealsense	1.12.1
Camera Type-Firmware	SR300 - 3.15.0.0

Expected Behavior

After launching camera I expect published images to have a time stamp that updates as the node runs

Actual Behavior

all images received have the same time stamp from when the node was started.

Steps to Reproduce

roslaunch realsense_camera sr300_nodelet_default.launch
For a quick check I have been looking at the camera_info topic because it uses the same time stamp
rostopic echo /camera/color/camera_info

Removing the static declaration from the variable last_common_stamp fixed the problem for me

  /*
   * Determine the timestamp for the publish topic. -- overrides base class
   */
  ros::Time SR300Nodelet::getTimestamp(rs_stream stream_index, double frame_ts)
  {
    static ros::Time last_common_stamp = ros::Time::now();

    if (stream_index == fastest_stream_)
    {
      last_common_stamp = ros::Time::now();
    }

    return last_common_stamp;
  }

If this is a reasonable fix I can issue a pull request.

Thanks,
-Marq

[mdhorn]

The problem was introduced when we switch from polling to callbacks. To help align the color and depth using callback we were only updating the timestamp with via the fastest stream. What was not accounted for is if the faster stream (by default depth) doesn't have subscribers, the code which updates the timestamp is never called.

This will be fixed in the next major release as we are rolling back to polling for SR300/F200/R200 camera as the callbacks aren't fully functional of the older cameras.

One possible work around here is to have subscribers on both the color and depth stream.

The other recommendation would be pulling the code from the 1.6.1 release tag and building locally.

[MarqRazz]

Thanks for pointing me in the right direction mdhorn! Any ideas on when the next release will be out?

[mdhorn]

It will likely take 4+ weeks before the fix is pushed and tested; then the random 2-8 weeks before the next ROS package sync.

For now, I'd recommend building 1.6.1 from sources, and watch the repo for a patch.

[mkhansenbot]

@MarqRazz - I have a PR #209 that I think fixes this issue, would you like to clone it and try it out?

[MarqRazz]

@mkhansen-intel

I ran some more tests today and can confirm that PR #209 does fix this issue.

Thanks for your help!

[mdhorn]

Resolved in release 1.8.0
Available now by pulling tag 1.8.0 and building from sources.
Released to ROS Build Farm. Available in Shadow Repository once PR 14443 for Indigo and PR 14444 for Kinetic are merged.
Public ROS repository packages available after next sync (1-3 weeks) by OSRF.