Frame preview
Outer edge 6804 × 4694 px, photo window 6500 × 4390 px. Click any border plate or corner below to try it here. Each side is stretched very slightly so it holds a whole number of repeats.
Whole frame, scaled down. Grey marks the photo window, which is transparent in the download.
Top-left corner at 1:1.
Corners
152 × 152 ornaments for the corner squares. Each is drawn for the top-left corner and mirrored into the other three.