Hardware manual

Impact Reference Guide OCR
3-183 Datalogic Automation Inc.
How to set up the OCR tool
1. Snap a good image of the desired characters then click the Setup tab.
2. Click the ROI radio button. Move and size the ROI so it fits closely around all the characters you want
to inspect. Only the characters to be verified should be inside the ROI so try to avoid including parts of
the background. Only one row of characters can be contained within the ROI.
3. Select an ROI Type, based on the character and background contrast. See “Threshold Types” on
page 3-186. Generally, the default Adaptive Threshold choice is the most appropriate.If the image is
noisy, adjust the Noise Sensitivity Slider. The default setting will work for most applications. Any time
you change a value or move the ROI, the tool will run and should find characters.
4. You can adjust the Character Box settings to accommodate any special characteristics of the letters in
your image and to exclude small background anomalies. For example, if the characters are different
widths or heights, or the spacing is uneven. You should select Use Variable Character Width if the
Character Success
List
A list of each character’s match success or failure.
If there are missing or extra characters in the Output String, the tool will
identify and skip over them, allowing the rest of the string to match. In
these cases, the tool will fail overall because the Output String and verifi-
cation string must match exactly, but the “Character Success List” will
now indicate characters that are successfully read and verified to the
right of the missing or extra characters.
Match Scores The match scores for each of the input characters
Thresholds Used When Threshold Type is set to Block Adaptive mode, each character can
have a different threshold, so this list contains the threshold value used
for each character. In Adaptive Threshold mode this list will have the
same value for each character.
Successful Read True if all the characters in the input string are present in the font library.
If the Verify String is present, the input string must match it.
Output Name What it is