Strange distortion in rectified image (stereo_image_proc)

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Hi all, I'm new here (and new to ROS), so let me know if I'm doing anything wrong.

Our underwater submarine team is having some difficulty getting stereo_image_proc to produce any stereo information. When I run stereo_view, I get an error saying that there are not enough synched triplets (in fact I can see that there are 0 disparity images), and even when I run with a huge queue_size and approximate_sync=True, I see no left image, no right image, and no disparity image. I can image_view the left and right image separately, but stereo_view doesn't like them, I just get grey boxes.

That same sync error says to rostopic info stereo_view_[131...], and doing so reports no connection, but the documentation isn't clear on what this implies.

This led me to check my stereo/left/image_rect topic, and I was met with a strangely distorted image. I don't understand why my image is being rectified like this, but I think if I knew, I might be closer to fixing this problem.

http://imgur(dot)com/a/rE0CU here is a picture of what we're seeing from stereo/left/image_rect

Here is what I think I might be doing wrong, let me know if any of these stand out: To begin with, our stereo cameras are two separate flea3 USB cameras mounted in water-tight enclosures about a foot apart. We have them centered at about 8 feet, although this is imperfectly done at best.

Secondly, we are transporting information over USB 2.0 because our wet-matable plugs are not rated for USB 3.

Third, the images are coming it at a pretty high resolution, and apart from compressing and republishing them, I don't think there is a way that I can reduce the resolution (pgr_camera_driver doesn't natively support low resolutions on the flea3, I guess)

I am running ROS fuerte on linux, let me know if there is any more info you need. Thanks so much, really appreciate the help.