Render in Movie Render Queue with High Resolution Tiling Overlap causes dark pixels

From UDN:

thanks for your reply.

I have attached a very basic scene with a MRQ settings preset.

The only thing I have changed in the scene is that I've set the Camera Exposure to manual, as it does not work otherwise with the MRQ settings.

There should be an image in the render folder ready for you, where you can see the shaded pixels in the bottom row and right column.

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I think we have found a bug when using High Resolution in MRQ when the Overlap Ratio > 0.0. It does not appear if the OR is 0.

When using this setting (with 4 tiles) a dark border appears at the right and bottom edge of the image, which is always 1 pixel wide.

This would not be noticeable on a 2D image, but we are stitching together 4 images to create a fisheye, which leaves us with a dark line in the middle of the image.

Since our fisheye is 8K you might not see it at first glance, but you should see it if you zoom in.

I looked into the source code and could not pinpoint the problem, but this seems like an edge case where the tiling overlap function tries to sample outside of the image when it reaches the right/bottom edge.

I guess you should be able to reproduce the issue when using these settings, and zooming in on the edge of the image to see the pixel artifact.

From a UDN case [Link Removed]

1. Open the attached project
2. Create a new MRQ job with TestSequence + TestPreset 
3. Render (Local)

Note the bottom and right row of the rendered output has pixels shaded darker than they should be.  This would case issues when stitching multiple renders together.