Whats the difference between TWAIN and ISIS?
ISIS is a proprietary interface standard. Companies that want to develop an ISIS-based scanning application, or build a scanner with ISIS drivers, must pay a licensing fee. The ISIS standard is tightly controlled, so scanning applications and scanners which use it deliver consistent results. Businesses usually are willing to pay extra for this assured level of consistency. TWAIN, on the other hand, is an open standard companies can use without having to pay a licensing fee. This helps keep the price of products low, which is appealing to consumers. TWAIN, however, is not as tightly controlled as ISIS, and subtle differences in how the standard is interpreted and implemented by companies can lead to inconsistent results. A TWAIN-based product from one company may not always be able to communicate with a TWAIN-based product produced by another company.
ISIS (Image and Scanner Interface Specification) is a proprietary scanner interface developed by Pixel Translations in 1990 (today: EMC captiva).
Unlike TWAIN, produced by a non-profit organization, ISIS doesn’t come for free. Scanner vendors need to pay a royalty fee in order to use the ISIS driver. Although ISIS was originally targeted for a production environment (higher volumes, supporting advanced features of high end scanners), the high cost is driving vendors away. As a result, ISIS is not popular in enterprises.
More details can be found at in the article: http://www.dynamsoft.com/blog/document-imaging/document-scanning-twain-wia-isis-sane/
