How to visualise points on images in rviz?

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Autoware includes an rviz plugin called imageviewerplugin that lets you view bounding boxes and also a "Point topic" which I assume lets you put points on images.

C:\fakepath\IVP.png

I am currently calculating 2d point coordinates in some image frame and projecting them into another and I'd like an easy way of visualising those points on the images. this seems likely to be what this plugin is for (?)

inspecting the message time expected for points:

PointsImage.msg 
Header header
float32[] distance
float32[] intensity
float32[] min_height
float32[] max_height
int32 max_y
int32 min_y
int32 image_height
int32 image_width

I can't really understand these fields. Am I on the right track? How can I visualise points on images? or is there some hidden documentation for this plugin?