Notes On Four-Point-Coordinates Recognition Errors - Hitachi HT-4139-28 Troubleshooting Manual

Troubleshooting
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otes on Four-Point-Coordinates Recognition Errors
Four-point-Coordinates Recognition errors may occur depending on the status of images having
been scanned. These errors occur when the four corners of a sheet failed to be detected.
These errors are usually caused from the following problems.
(1) Error resulting from soil at the reference side
- This error occurs when white vertical noise is made due to dust such as paper dust.
Open the opening/closing part at the front and check that there is no dirt on the glass of the
scanning unit. Cleaning requires you to use a piece of gauze or other cloth that is as new as
possible. Wiping the glass with a soiled cloth may increase the error detection.
(2) Imperfect image error
- This error occurs when a large skew causes a part of the sheet to get outside the image area
and makes a part of the image look imperfect.
Check that the sheet is not skewed when it is being sent.
(3) Rectangular detection error
This error occurs when detected 4 points do not make a rectangle with them.
Check that the sheet.
(4) Other errors (such as a tip error and a left end error)
- These errors occur when the entire image is completely black.
- These errors occur when the image is spotted with white noises.
- These errors occur when the image contains an extremely small white area.
Check the sheet.
You may fail to scan a sheet not conforming to the specifications.
For the specifications of the sheet, refer to the "OCR Friend Operation Guide".
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