Bitmap Images
LinkCAD can import raster images (bitmaps) and convert them to vector polygon geometry suitable for mask layout or CAD conversion.
Format Summary
| Property | Value |
|---|---|
| Extensions | .bmp, .png, .jpg, .jpeg, .tif, .tiff |
| Encoding | Binary (various) |
| Import | |
| Export | — |
| License | Basic |
How It Works
Bitmap import traces the raster image to produce vector polygons:
- The image is thresholded to separate foreground from background
- Contour tracing identifies polygon boundaries
- Polygons are generated from the traced contours
- Coordinates are scaled based on the specified DPI and units
Import Options
| Option | Description | Default |
|---|---|---|
| DPI | Resolution of the source image | 300 |
| Units | Target coordinate units | Micron |
| Threshold | Brightness threshold for black/white separation | 128 |
Common Workflows
Bitmap → GDSII
Convert scanned mask images or bitmap artwork to GDSII layout data.
Bitmap → DXF
Vectorize raster graphics for use in CAD tools.
Technical Notes
- The vectorization process works best with clean, high-contrast black-and-white images
- Anti-aliased or blurred edges may produce noisy polygon boundaries
- For best results, use high-resolution (300+ DPI) images with sharp edges
- Color images are converted to grayscale before thresholding
- Very large images may require significant memory and processing time
CLI / Command-File Options
These option keys can be used on the command line or in command files.
Import
| Key | Type | Description |
|---|---|---|
RasterInScalingUnits |
int | Scaling unit enum (see Units) |
RasterInScalingValue |
float | Scaling value |
RasterInScalingValueY |
float | Y-axis scaling value (non-square pixels) |
RasterInGrayLevels |
int | Number of gray levels for vectorization |
RasterInKeepWhite |
flag | Keep white pixels as shapes |
RasterInMergeType |
int | Merge mode — 0=none, 1=horizontal, 2=all adjacent |
RasterInProcessing |
int | Processing mode — 0=threshold 50%, 1=dither, 2=split gray levels |