Grab Image from Gazebo with C++

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I'm trying to write a C++ program that will allow me to capture a single frame from a camera in Gazebo. The Gazebo camera itself is working because I can see a live feed with the Topic Visualizer. I already got the publishing part working. Is there a ROS or Gazebo equivalent for the following 2 lines that will allow my C++ node to "latch onto" Gazebo and subscribe to the image data?

playerccamerasubscribe(camera1, PLAYEROPENMODE); *realFrame = cvQueryFrame( capture );