=====================================
Tutorial For RealSense-based Encoding
=====================================

In this tutorial, you perform H.264 encoding
using a
`RealSense <https://www.intel.com/content/www/us/en/architecture-and-technology/realsense-overview.html>`__
camera and
:ir_repo:`isaac_ros_h264_encoder <isaac_ros_compression> <isaac_ros_h264_encoder/src/encoder_node.cpp>`
to save compressed images into a rosbag.

.. note::

   This tutorial requires a compatible RealSense
   camera from the list of
   :ref:`cameras <getting_started/hardware_setup/sensors/realsense_setup:camera compatibility>`.

1. Complete the :doc:`RealSense setup tutorial </getting_started/hardware_setup/sensors/realsense_setup>`.
2. Complete steps 1-2 as described in the :ref:`quickstart guide <repositories_and_packages/isaac_ros_compression/isaac_ros_h264_decoder/index:quickstart>`.
3. Open a new terminal and launch the Docker container using the
   ``run_dev.sh`` script:

   .. code:: bash

      cd ${ISAAC_ROS_WS}/src/isaac_ros_common && \
        ./scripts/run_dev.sh

4. Build and source the workspace:

   .. code:: bash

      cd /workspaces/isaac_ros-dev && \
        colcon build --symlink-install && \
        source install/setup.bash

5. Run the launch file. This launch file launches the example and
   saves ``CompressedImage`` and ``CameraInfo`` topic data into a rosbag
   in your current folder:

   .. code:: bash

      ros2 launch isaac_ros_h264_encoder isaac_ros_h264_encoder_realsense.launch.py

6. (Optional) If you want to decode and visualize the images from the
   rosbag, you can place the recorded rosbag into an x86 machine
   equipped with NVIDIA GPU, then follow steps 7 and 8 in the
   :ref:`Quickstart section <repositories_and_packages/isaac_ros_compression/isaac_ros_h264_encoder/index:quickstart>`. (Change the rosbag path and
   input the dimension accordingly in step 7):

   .. code:: bash

      ros2 launch isaac_ros_h264_decoder isaac_ros_h264_decoder_rosbag.launch.py rosbag_path:=<"path to your rosbag folder"> input_width:=640 input_height:=480

For example, the result looks like:

.. figure:: :ir_lfs:`<resources/isaac_ros_docs/concepts/compression/h264/realsense_example.png>`
   :align: center