Extract images and timestamps from a rosbag file.

Author: David Zuñiga-Noël

License: GPLv3

• CMake (3.5.1-1ubuntu1)

  sudo apt install cmake
  

• ROS (Kinetic Kame)

  See ROS installation.

• Gflags (2.1.2-3)

  sudo apt install libgflags-dev
  

• libpng (1.2.54-1ubuntu1.1)

  sudo apt install libpng-dev
  

Once all dependencies are installed, proceed to build the source code with the automated build script provided. Simply run the following commands:

git clone https://github.com/dzunigan/bag_to_image.git
cd bag_to_image
bash build.sh

The compiled executable should be inside the bin directory.

The input is a rosbag file and the topic where the images were published. The output is the sequence of images, compressed in PNG format and a CSV file with correspoinding timestamps in nanoseconds.

The bag_to_image tool can invoked as follows:

bag_to_image [options] <rosbag> <topic>

where the available options are:

• --output_path=desired_path: to set the output root directory

• --images_dir=desired_dir: to set the images directory name (inside output directory)

• --timestamps_file=desired_file: to set the output timestamps filename (inside output directory)

• --compression_level=compression_level: to set the PNG compression level (between 0-9)

• --show_images: to preview the images during extraction