What are the information represented by echo the topic of camera_info and image_raw?

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Hi, I am using a multi camera plugin with SDF and the left and right images are published well in Rviz2. I wish to know the depth/distance of the object from the camera based on the images produced hence I try to echo the topic of camera_info and image_raw. For camera_info, I get: d : - 0.0 - 0.0 - 0.0 - 0.0 - 0.0

k: - 476.703... - 0.0 - 400.5 - 0.0 - 476.703... - 400.5 - 0.0 - 0.0 - 0.0 - 1.0

r: - 1.0 - 0.0 - 0.0 - 0.0 - 1.0 - 0.0 - 0.0 - 0.0 - 1.0

p: - same as k

while for image_raw topic, i get number range from 153 to 158.

May i know what are all these information means? And how can I use these information for my purpose to identify the distance of object?

Thank you in advanced.