gscan2pdf is a GUI to ease the process of producing PDFs from scanned documents. You scan in one or several pages and create a PDF of selected pages. Scanning is handled with SANE via scanimage. PDF conversion is done by PDF::API2. Perl is used for portability and ease of programming, with gtk2-perl for the GUI.
ExactScan is a versatile document capture application for home offices and workgroups. It is designed from the ground up for high-speed document scanners and can easily handle hundreds of images per minute, including duplex scans. Included functionality reaches from managing, sorting, and editing singles pages to writing multi- as well as single-page PDF files including JPEG compression and TIFF, JPEG, JPEG2000, and PNG bitmap files. ExactScan allows performing state of the art image processing including automatic cropping, deskewing, dynamic thresholding for perfect black and white documents, and descreening print rasters.
LibRaw is a library for reading RAW files obtained from digital photo cameras (CRW/CR2, NEF, RAF, DNG, and others). LibRaw is based on the source codes of the dcraw utility, though some of the drawbacks of dcraw have been eliminated. The users of the library are provided with an API to be used when writing their software programs.