1. Create a square transparent canvas
  2. Add your (circular) logo
  3. Apply Filter>Distort>Polar>Polar To Rectangular
  4. Image>Image Rotation>Flip Canvas Vertical
  5. Image>Image Rotation>Flip Canvas Horizontal
  6. Copy (CTRL-C)
  7. Paste (CTRL-V) into your equirectangular panorama
  8. Resize to fit the full width
  9. Resize the height as desired
  10. Place at the bottom of your image
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