caidish/klayoutclaw/image

KLayout Image Overlay

Load reference images (JPG, PNG, BMP) into KLayout as background overlays for aligning device geometry to real microscope photos.

Prerequisites

• KLayout running with KlayoutClaw plugin (v0.5+)
• A layout must be open (use create_layout first if needed)

Scripts

add_image.py — Load an image as background overlay

python scripts/add_image.py <filepath> [--pixel-size 0.1] [--scale-bar <um> <pixels>] [--x 0] [--y 0] [--center]

• filepath — Path to image file (JPG, PNG, BMP)
• --pixel-size — Microns per pixel (default: 1.0)
• --scale-bar — Derive pixel size from a scale bar: <length_um> <length_pixels>. Takes priority over --pixel-size.
• --x, --y — Position offset in microns (default: 0, 0)
• --center — Center the image at the given position (default: image corner at position)

Example — set pixel size directly:

python scripts/add_image.py ~/photos/graphene.jpg --pixel-size 0.1

Example — derive pixel size from a 20 um scale bar that spans 153 pixels:

python scripts/add_image.py ~/photos/graphene.jpg --scale-bar 20 153 --center
# Output: Scale bar: 20.0 um / 153.0 px = 0.1307 um/px

Example — load and center at a specific position:

python scripts/add_image.py ~/photos/flake.png --pixel-size 0.05 --x 100 --y 50 --center

list_images.py — List all background images in the view

python scripts/list_images.py

Prints a table of all loaded images with their ID, filename, position, and visibility.

remove_image.py — Remove a background image

python scripts/remove_image.py <image_id | all>

• image_id — Numeric ID of the image to remove (from list_images.py)
• all — Remove all background images

Workflow

1. Load a microscope image as reference background
2. Use geometry scripts to draw device features (contacts, gates, mesa) on top
3. Adjust pixel-size to match the image's physical scale (check the scale bar)
4. Use list_images.py to see loaded images, remove_image.py to clean up

Estimating pixel-size

If the image has a scale bar of length S microns spanning P pixels:

pixel-size = S / P

For example, a 20 um scale bar that spans 200 pixels gives pixel-size = 0.1.