<launch>
  <node pkg="rosbag" type="play" name="rosbagr" args="$(find bag_to_depth_image)bagfile/newrgb.bag"/> 
  <node name="extract_r" pkg="bag_to_depth_image" type="extract_images" respawn="false" output="screen" cwd="node">
    <remap from="image" to="/camera/rgb/image_raw"/>
  </node>
</launch>

That's my launch file. I want to change the directory where the rosbag file is saved, with cwd I have only choice between node and home cwd="ROS_HOME|node"

I have to record a very big file with thousands of images from depth and rgb. So i want to save the rosbag file in a different location.