Hi, I’m software and database developer with more than 30 years experience. In the past 20 years I have worked (full-time, in-situ) for two international organizations (Inter-American Tropical Tuna Commission, in San Diego, CA, and the Food and Agriculture Organization (FAO) of the United Nations, in Victoria, Seychelles). I'm currently retired, and doing some freelancing to stay busy and up-to-date in the area.
I have already done similar jobs to the one you require. I found two possible approaches:
1) Develop the code to interface directly to the TWAIN drivers from the application. This is possible through an available TWAIN control. Advantages: single customized application. Disadvantages: the Twain control has some limitations.
2) Keep using your current scanning software, and add a service that will detect new files in the target directory, scan the barcode and rename the file. Advantages: keep using familiar software, usually all TWAIN options are available. Disadvantages: requires tweaking on networks setups
I have developed applications using both approaches. In both cases, I used ZXing library to handle the barcodes.
If you think you may be interested in my services, please send me PM. This way we can further discuss your requirements and I can share a copy of my CV with you, for you to check references/experience.
Best regards,
Marco Garcia