2. Copy data from a source
Scanners take paper and convert it into a bitmap
Types of scanners
Optical scanner
Bar code readers
Character and Mark recognition
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3. Convert text or drawings into machine
readable format
Can be displayed, printed, or stored
Types of optical scanners
Flatbed scanner
Source placed on glass surface
Image scanned from below
Portable scanner
Handheld device that slides across source
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4. Flatbed scanner
If we talk about scanners, thus we mean usually flatbed scanner.
The scan documents (texts, photo, diagrams etc..) are put on a
glass plate like a copier, under which a carriage with an exposure
item and the read head moves. Then the picture is scanned The
picture information is entered by a CCD (Charge Couple
Device). CCDs are semiconductor chips, with an array of photo-
sensitive cells, which are used for the transformation from
electromagnetic waves of light into electrical signals.
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5. Photoelectric scanner
Using Optical Recognition, a light beam scans the item and
changes it into electrical impulses for processing Contain
photoelectric cells that read bar codes
Read bar codes
Alternating black & white vertical bars
Universal Product Code (UPC)
Seen in grocery stores, retail stores
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6. Magnetic-ink character recognition (MICR)
Reads magnetically encoded characters
Optical-character recognition (OCR)
Optical character recognition (OCR) converts
bitmap back into text
• different fonts create problems for simple
“template matching”
algorithms
• more complex systems segment text,
decompose it into lines and arcs, and decipher
characters that way
Optical-mark recognition (OMR)
Senses presence or absence of marks
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7. A flatbed scanner scans one sheet at a time by laying
the sheet face down on the bed of the scanner
Sheetfed scanner use motorized rollers to feed the
document across the scanning mechanism
Handheld scanner-portable device that requires users
to pass the scanning element over the item to be
scanned
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8. Bar codes-each product has a unique product
code (UPC) represented by a pattern of bars
Bar code scanner scans the bars using
reflected light which is then processed to
retrieve product information assigned to that
bar code
Handwriting Recognition
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9. Scanners are typically envisioned as connected to a co-
located host computer.
Submitting “Jobs” to network scanners is unnatural
since a walk-up user must be present to submit the
originals anyway.
Jobs may be most naturally started at the scanner and
not at a workstation.
Will be more prevalent as networked MFPs provide
scanning capability.
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10. Archive-Communicate
recording a facsimile of an image, such as a form or a
signature for storage, transmission or reproduction.
Parameters and area probably well defined, fidelity important.
Includes Copying, Fax.
Modify-Reproduce
Capturing an image for inclusion in a document or display,
often with modification, scaling, cropping, etc. Parameters
may not be known and area to be scanned may be
inconsistent, fidelity important.
Extract-Analysis
Processing an image for analysis or interpretation, such as
OCR or feature analysis. Parameters and area probably well
defined, fidelity not too important for extraction. Analysis
required very high fidelity.
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11. Character and mark recognition devices
Scanners that recognize special characters &
marks
Magnetic ink character recognition (MICR)
Optical-character recognition (OCR)
Optical-mark recognition (OMR)
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12. Scanners read and
interpret information
on printed matter
The information is
converted to a format
for storage
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13. Grades test
Checks survey
The sense marks are
compared on the test by
the scanner
Corrections are
calculated
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14. Scanners capture and digitize printed images.
There are several types of scanners:
Flatbed scanners
Handheld scanners
Sheet-fed scanners
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15. Item to be scanned is to be pulled into a
stationary scanning mechanism
Smaller and less expensive than flatbed
scanner
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16. Item to be scanned rotates around stationary
scanning mechanism
Very large and expensive
Used in the publishing industry.
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Scanning devices read data or information from a physical source such as a written document, a price tag, or a picture. Three basic types: optical -- text and image; Barcode – wand readers and platform scanners; Character mark recognition – special characters
The scanner record the light and dark areas as well as the color of the source document. Flatbed scanners are like a copy machine. The source is place on top of the device to scan. Portable scanners make direct contact with the source material and is dragged by hand across it.
The photoelectric scanners are usually wand readers(portable handheld scanner) or platform scanners (mounted to a platform like a counter). UPC is a system by which every product is uniquely identified by manufacturer code and product code. Scanners read the UPC and lookup the item in a database to retrieve information, such as price.
Character and mark recognition devices MICR - used by banks to read magnetically encoded characters on check. The ink is mixed with magnetic particles. OCR - specially preprinted characters are read by OCR devices such as wand scanners such as seen in retail stores. OMR - devices sense the presence or absence of marks, common for test scoring such as the SAT and GRE test.
Character and mark recognition devices MICR - used by banks to read magnetically encoded characters OCR - specially preprinted characters are read by OCR devices such as wand scanners OMR - devices sense the presence or absence of marks, common for test scoring