Aspect ratio
PDF417 symbols may be reproduced with different number of codewords per row, and therefore in several different height to width ratios.
The user may select either target ratio (as the height to width ratio) or the required number of codewords per row. In general tall, thin barcodes read more reliably than short, wide symbols, although there may be restrictions applied by the type of barcode scanner employed.
The Aspect ratio is set for PDF417 barcodes by calling the setAspect() function.
