ROS

Lecture series on ROS programming: https://www.youtube.com/playlist?list=PLE-BQwvVGf8HOvwXPgtDfWoxd4Cc6ghiP

Official ROS beginner tutorials (skip intermediate): http://wiki.ros.org/ROS/Tutorials

Basic concepts of ROS by clearpath http://www.clearpathrobotics.com/assets/guides/kinetic/ros/Intro%20to%20the%20Robot%20Operating%20System.html

The construct for (paid) courses on many robot topics: https://www.theconstructsim.com/robotigniteacademy_learnros/ros-courses-library/

Building a model in Gazebo: https://www.youtube.com/playlist?list=PLTEmcYHVE7dPWixFnzkd68jPjwGzxH

Rosbag to video file

Requires prerecorded bag file:

http://wiki.ros.org/rosbag/Tutorials/Exporting image and video data

also:

https://medium.com/@kalyc0/detecting-objects-from-a-rosbag-recording-using-yolo-88b28043b249

Important: To build .mpg-file from jpgs we need to know the framerate. If seconds per frame is set to 0.1, then frames per second is 10.

Standard seconds per frame in .launch file is set to 0.1. If we want to extract more frames per second this needs to be set to a lower value. Add this to the .launch file, under <remap from=...........>

<param name="sec_per_frame" value="<your_value>"/>

Source: https://answers.ros.org/question/229251/exporting-jpegs-from-bag-file-skips-frames/

Note: if these tutorials fail to create a proper video from your images, do this command in your frames-folder, instead:

$ mencoder "mf://*.jpg" -mf w=800:h=600:fps={​FRAMERATE}​:type=jpg -ovc copy -oac copy -o {​OUTPUT_FILENAME}​.avi

Worked much better!

Source: http://www.mplayerhq.hu/DOCS/HTML/en/menc-feat-enc-images.html