Document Scanners and Scanning
Document Scanners
Document Management and Document Imaging systems require document scanners to scan paper documents and save them as images. Here are a few points to look for:
Flatbed or Sheetfeed ?
A Flatbed Scanner allows you to position a document on the glass and scan it. This provides the flexibility to scan damaged or fragile documents, books or stapled documents but is a relatively slow method of scanning.
A Sheetfeeder (or Automatic Document Feed) allows a pile of documents to be scanned, though all must be in good condition and unstapled.
Some scanners offer both Flatbed and Sheetfeed. Sheetfeed-only scanners are typically faster than dual purpose scanners.
Colour or Monochrome ?
Most Document Imaging requires Black and White scanning. There is usually little point in scanning, say, Invoices or Letters in colour.
In many cases Drawings and Photographs are better scanned in Greyscale (that is in various shades of grey) rather than Black and White.More and more there is a requirement to scan in colour. Colour leaflets and photographs can be accurately reproduced with a colour scanner. You should identify your requirements and select a suitable scanner.
Duplex ?
Duplex scanning is the ability to scan both sides of a sheet of paper at the same time. The requirement for this feature is entirely dependent upon the type of documents you wish to scan.
A4 or A3 or larger ?
Most document scanners scan A4 (or Letter) sized documents. Optionally A3 scanners may be preferred (these will also scan A4 of course). Larger formats such as A0 size are also available.
Scan Speed ?
Document Imaging scanners are available in a range of scan speeds. 10-15 pages per minute is usually the minimum acceptable speed. Mid range scanners typically scan at 20-45 pages per minute whilst production scanners scan at over 50 pages per minute. Scan speeds are available at up to 120 pages per minute.Duplex Scanners (see above) can scan both sides of a page at the same time resulting in higher scan speeds (when measured in images per minute rather than pages per minute).
Note that most manufacturers quote scan speeds when scanning at 200dpi, higher resolutions will result in lower speeds.
Resolution ?
Scanners allow a choice of resolution. Typically the higher the resolution the better the quality of the scan but the storage requirement will also be more.Resolution is measured in dots-per-inch (dpi).We normally recommend scanning monochrome documents at 200dpi or 300 dpi. If you also wish to OCR (see below) a document 300dpi is preferred.There is normally no advantage in scanning in a document at a higher resolution than it was originally printed. If a letter was printed on a laser printer at 300dpi scanning at more than 300dpi will not improve it.
Note that scanners achieve a given resolution in two possible ways - either by scanning optically at that resolution or by scanning at a lower optical resolution and then digitally enhancing the scan. A scanner with a high optical resolution will give better results than a scanner that relies on digital enhancement.
Personal, Workgroup or Production Scanners ?
The strategy for scanning will depend upon your particular requirements. You may provide individual users with their own (usually small and low-speed) scanners, you may provide a workgroup or department with a shared (usually mid-range) scanner or you may have a dedicated scanning facility (using high speed production scanners).
A typical Personal scanner, sheetfeed-only 25 pages per minute Colour and Monochrome.
Optical Character Recognition (OCR)
A scanned image is rather like a photograph or photocopy. You cannot electronically 'read' or edit the text on it. Optical Character Recognition gives you this facility. OCR will convert any text it finds on an image into electronically readable text. This text may then be edited (by Word Processing software, for example) or may be stored with the scanned image to enable searching for a given word or phrase.
TWAIN Scanning
TWAIN is an industry-standard method of allowing software to communicate with a scanner. A software package (such as Alliance Imager) can drive a scanner using TWAIN. The physical connection of a scanner to a PC will typically be via a SCSI or USB connection.
Imaging for Windows uses TWAIN scanning drivers.
KOFAX VRS Scanning
An alternative method for a software package (such as Alliance BatchScan scanning) to drive a scanner is to use a Kofax Adrenaline interface card. This provides a physical connection of scanner to PC and also the driver software. Kofax is especially suitable for high speed scanners.
An enhancement to Kofax is Virtual ReScan scanning enhancement.Virtual ReScan (VRS) enables you to get perfect scans every time. As quickly as images pass through the scanner, VRS performs a multi-point inspection of each document. It instantly checks and corrects for alignment (skew), brightness, contrast, and image clarity, so that only the best images are moved into your application.
Note that not all scanners can support Kofax.
Application Software
Scanners need application software to drive them. A document management application, such as Alliance Imager document imaging or Alliance PaperChase records management can scan and index the scanned documents. This is typically suited to relatively low volumes of scanning.
For large volumes of scanning a dedicated batch scanning program is recommended. Alliance BatchScan scanning software scans and stores at high speed for subsequent indexing.
Most scanners are suitable for use with Microsoft/Kodak/Wang Imaging for Windows.
Indexing is the entry of data against each scan so that the document may be found when required. The amount of data entered for each document will be dependent upon the requirements of your application.Indexing may be manual (by typing in the required data) or automatic (from a barcode printed on the document, or from OCR, or by sequential numbering).
Scanner Manufacturers
We supply scanners from a range of manufacturers including:
Fujitsu scanners for document management and document imaging.
Kodak scanners for document management and document imaging.
Canon scanners for document management and document imaging.
And other scanners for document management and imaging including Bowe, Bell and Howell and Xerox.
Document Management and Document Imaging systems require document scanners to scan paper documents and save them as images. Here are a few points to look for:
Flatbed or Sheetfeed ?
A Flatbed Scanner allows you to position a document on the glass and scan it. This provides the flexibility to scan damaged or fragile documents, books or stapled documents but is a relatively slow method of scanning.
A Sheetfeeder (or Automatic Document Feed) allows a pile of documents to be scanned, though all must be in good condition and unstapled.
Some scanners offer both Flatbed and Sheetfeed. Sheetfeed-only scanners are typically faster than dual purpose scanners.
Colour or Monochrome ?
Most Document Imaging requires Black and White scanning. There is usually little point in scanning, say, Invoices or Letters in colour.
In many cases Drawings and Photographs are better scanned in Greyscale (that is in various shades of grey) rather than Black and White.More and more there is a requirement to scan in colour. Colour leaflets and photographs can be accurately reproduced with a colour scanner. You should identify your requirements and select a suitable scanner.
Duplex ?
Duplex scanning is the ability to scan both sides of a sheet of paper at the same time. The requirement for this feature is entirely dependent upon the type of documents you wish to scan.
A4 or A3 or larger ?
Most document scanners scan A4 (or Letter) sized documents. Optionally A3 scanners may be preferred (these will also scan A4 of course). Larger formats such as A0 size are also available.
Scan Speed ?
Document Imaging scanners are available in a range of scan speeds. 10-15 pages per minute is usually the minimum acceptable speed. Mid range scanners typically scan at 20-45 pages per minute whilst production scanners scan at over 50 pages per minute. Scan speeds are available at up to 120 pages per minute.Duplex Scanners (see above) can scan both sides of a page at the same time resulting in higher scan speeds (when measured in images per minute rather than pages per minute).
Note that most manufacturers quote scan speeds when scanning at 200dpi, higher resolutions will result in lower speeds.
Resolution ?
Scanners allow a choice of resolution. Typically the higher the resolution the better the quality of the scan but the storage requirement will also be more.Resolution is measured in dots-per-inch (dpi).We normally recommend scanning monochrome documents at 200dpi or 300 dpi. If you also wish to OCR (see below) a document 300dpi is preferred.There is normally no advantage in scanning in a document at a higher resolution than it was originally printed. If a letter was printed on a laser printer at 300dpi scanning at more than 300dpi will not improve it.
Note that scanners achieve a given resolution in two possible ways - either by scanning optically at that resolution or by scanning at a lower optical resolution and then digitally enhancing the scan. A scanner with a high optical resolution will give better results than a scanner that relies on digital enhancement.
Personal, Workgroup or Production Scanners ?
The strategy for scanning will depend upon your particular requirements. You may provide individual users with their own (usually small and low-speed) scanners, you may provide a workgroup or department with a shared (usually mid-range) scanner or you may have a dedicated scanning facility (using high speed production scanners).
A typical Personal scanner, sheetfeed-only 25 pages per minute Colour and Monochrome.
Optical Character Recognition (OCR)
A scanned image is rather like a photograph or photocopy. You cannot electronically 'read' or edit the text on it. Optical Character Recognition gives you this facility. OCR will convert any text it finds on an image into electronically readable text. This text may then be edited (by Word Processing software, for example) or may be stored with the scanned image to enable searching for a given word or phrase.
TWAIN Scanning
TWAIN is an industry-standard method of allowing software to communicate with a scanner. A software package (such as Alliance Imager) can drive a scanner using TWAIN. The physical connection of a scanner to a PC will typically be via a SCSI or USB connection.
Imaging for Windows uses TWAIN scanning drivers.
KOFAX VRS Scanning
An alternative method for a software package (such as Alliance BatchScan scanning) to drive a scanner is to use a Kofax Adrenaline interface card. This provides a physical connection of scanner to PC and also the driver software. Kofax is especially suitable for high speed scanners.
An enhancement to Kofax is Virtual ReScan scanning enhancement.Virtual ReScan (VRS) enables you to get perfect scans every time. As quickly as images pass through the scanner, VRS performs a multi-point inspection of each document. It instantly checks and corrects for alignment (skew), brightness, contrast, and image clarity, so that only the best images are moved into your application.
Note that not all scanners can support Kofax.
Application Software
Scanners need application software to drive them. A document management application, such as Alliance Imager document imaging or Alliance PaperChase records management can scan and index the scanned documents. This is typically suited to relatively low volumes of scanning.
For large volumes of scanning a dedicated batch scanning program is recommended. Alliance BatchScan scanning software scans and stores at high speed for subsequent indexing.
Most scanners are suitable for use with Microsoft/Kodak/Wang Imaging for Windows.
Indexing is the entry of data against each scan so that the document may be found when required. The amount of data entered for each document will be dependent upon the requirements of your application.Indexing may be manual (by typing in the required data) or automatic (from a barcode printed on the document, or from OCR, or by sequential numbering).
Scanner Manufacturers
We supply scanners from a range of manufacturers including:
Fujitsu scanners for document management and document imaging.
Kodak scanners for document management and document imaging.
Canon scanners for document management and document imaging.
And other scanners for document management and imaging including Bowe, Bell and Howell and Xerox.
posted by VB6 Programming User at 8:29 PM
<< Home