od_compressed_image_transport

On Demand Compression and Decompression for ROS.

Problem Solved

Currently, the ROS image transport node that does compression and decompression automatically subscribes to the topic it is applyinbg said operation to even when we are not subscribing to it. This wastes resources on sensor or camera nodes by keeping the camera on. This is an extension to the existing compression/decompression node that only subscribes to the topic you want to decompress/compress when you subscribe to the output topic of the cfompression/decompression node.

Example

<launch>

    <!-- Args -->
    <arg name="queue_size"        default="5"/>
    <arg name="num_worker_threads"    default="4"/>
    <arg name="machine"           default="localhost"/>
    <arg name="nodelet_manager"   default="basler_bridge"/>
    <arg name="start_manager"     default="true"/>
    <arg name="use_machine"       default="true"/>
    <arg name="respawn"           default="false"/>
    <arg name="use_nodelet"       default="true"/>
    <arg name="calibrate"         default="false"/>

    <!-- Nodelet Manager -->
    <machine name="localhost" address="localhost" if="$(arg use_machine)"/>
    <node pkg="nodelet" type="nodelet" name="$(arg nodelet_manager)" args="manager"
    if="$(arg start_manager)" machine="$(arg machine)" output="screen">
    <param name="num_worker_threads" value="$(arg num_worker_threads)" />
    </node>

    <!-- Publisher
    <node pkg="nodelet" type="nodelet" name="compressed_publisher" machine="$(arg machine)"
    args="load od_compressed_image_transport/compressed_publisher $(arg nodelet_manager)" respawn="$(arg respawn)">
        <param name="queue_size" type="int" value="$(arg queue_size)"/>
        <param name="raw_topic_input" type="string" value="/Kinect1/hd/image_color_rect"/>
        <param name="compressed_topic_output" type="string" value="/Kinect1/hd/image_color_rect/compressed"/>
    </node>
    -->

    <!-- Subscriber
    <node pkg="nodelet" type="nodelet" name="compressed_subscriber" machine="$(arg machine)"
    args="load od_compressed_image_transport/compressed_subscriber $(arg nodelet_manager)" respawn="$(arg respawn)">
        <param name="queue_size" type="int" value="$(arg queue_size)"/>
        <param name="compressed_topic_input" type="string" value="/Kinect1/hd/image_color_rect/compressed"/>
        <param name="raw_topic_output" type="string" value="/Kinect1/hd/image_color_rect"/>
    </node>
    -->

</launch>