Pdf417decode imagefile|stringfile|-i
PDF417decode takes one parameter, which can be one of the following (1) the path
of the image file. The file can be JPEG, PNG, TIF or GIF. (2) a text file that
contains the barcode string (generated by PDF417 Fontware & Writer SDK 4). The
file name must have .txt as the extension. (3) -i,
which means that the barcode string will be entered through input.
The following commands are valid:
1. decode image file test-pdf417-scan.png
pdf417decode test-pdf417-scan.png
2. decode barcode string, stored in test-barstr.txt
pdf417decode test-barstr.txt
3. decode barcode string, entered through std input (C stdin)
pdf417decode -i