Gets or sets the barcode module size in graphic units (see Resolution).
Zero indicates the default which depends on the code type:
- 0.75 units for simple "bar" barcodes.
- 3.75 units for matrix barcodes (QRCode, DataMatrix).
- 3 units for RSS stacked barcodes (RSSStacked, RSSExpandedStacked).
- 2.25 units for Code49 barcodes.
- 1.5 units for MicroPDF417 barcodes.
- 2.25 units for composite barcodes.