What is TwinStream?

Historically, production scanners have always provided scan applications with black and white images, in spite of the fact that cameras inside the scanners generate grayscale images. Manufacturers have achieved this by developing complex circuits (like Bell+Howell Ace or Fujitsu IPC) that did on the fly conversion.

TwinStream is a technology developped by Dunord that brings both images (grayscale and black and white) simultaneously to an application that can then use both images as required to satisfy users' needs.

Why TwinStream?

Even though scanner manufacturers have put a lot of effort into building sophisticated conversion circuits, the result is not always satisfactory: trying to scan a document that contains a picture, a barcode and a signature usually results in severe headaches for the adventurous operator.

TwinStream offers the capacity to extract information from the gray image and:

• save it as is (typically a picture or a signature);
• use multiple conversion techniques on different zones in the gray image and rebuild the bi-tonal image (using VIR or your own algorithms);
• keep the bi-tonal image as archive and extract information from the gray image (OMR, barcode or OCR/ICR).

When is TwinStream needed?

TwinStream is needed when superior image quality is a must. Grayscale images supply the necessary high quality while its bi-tonal counterpart allows fast image compression and easy storage.

TwinStream interfaces are used by developers around the world in demanding applications. Typical applications are:

• Passport applications processing where the scanned document is kept in bi-tonal but the applicant picture is saved in gray.
• Fingerprint archiving systems where the fingerprints are kept in gray but the rest of the information is saved in bi-tonal.

The following scanner manufacturers make TwinStream compliant scanners:

• BancTec simplex or duplex 2610W
• Bell+Howell Copyscan II simplex or duplex with Ace circuit
• Improvision IS510 (simplex or IS520 (duplex) with PVSI card
• Inotec 2500 or 5000 simplex or duplex