Camera synchronization server

This repo contains a ROS node for recording sychronized images from several Pointgrey/FLIR Cameras.

Installation

Install the FlyCapture SDK from FLIR. If the installer fails because of missing dependencies, run apt --fix-broken install, and retry the installation. Do this several times, and eventually the installation will succeed.

Install the ROS flea3 drivers:

git clone https://github.com/berndpfrommer/flea3.git
git clone https://github.com/berndpfrommer/camera_base.git

Install and compile the code:

git clone https://github.com/daniilidis-group/cam_sync.git
catkin config -DCMAKE_BUILD_TYPE=Release
catkin build

VERY IMPORTANT: you MUST set the cameras to provide embedded image information, or else cam_sync will not work.

For that, start the flycap GUI, go to the Configuration section, find Advanced Camera Settings, select Memory Channels = 1, and then under Embedded Image Information enable Timestamp, Gain, Shutter, Brightness, Exposure, White balance and Frame counter. Hit Save before exiting. This must be done for each camera, but the settings will survive camera power cycling.

FAQ

1. Why does cam_sync crash when I run multiple USB3 cameras with it? This is often caused by insufficient USB3 memory limits in the kernel. On Ubuntu, edit /etc/default/grub to have a line like this:

   GRUB_CMDLINE_LINUX_DEFAULT="quiet splash usbcore.usbfs_memory_mb=1000"

then run sudo update grub. Then, for immediate relief:

sudo sh -c 'echo 1000 > /sys/module/usbcore/parameters/usbfs_memory_mb'

2. Does cam_sync need calibration files to work? No, but you want to provide them such that a correct camera_info topic can be published.

3. Why are the cameras dropping frames and not working as expected?

• Check that you enabled embedded image information as described above.
• Is there excessive load on the host?
• Check that you are getting full USB3 performance. You need to have each camera on a separate host chip, they cannot share. Here are some instructions for performance debugging USB3 performance issues.