Read Text Identification Tool

Train Font Button

Launches the Train Font dialog, where you will define and edit your fonts (Character Models and their instances).

Mode

Defines the operational mode of the tool: Read, Verify or Read and Verify.

Read: The tool decodes the text string based upon the trained Character Models. The decoded text string must match the number of characters defined in the Field String parameter.
Verify:The tool decodes the text string based upon the text string defined in the Match String parameter.
Read and Verify: The tool decodes the text string and compares the decoded string against the string defined in the Match String parameter. The decoded text string must match the string defined in the Match String parameter to be classified as a Pass..

Note: The tool has two states: Pass or Fail. When the tool's Mode control is set to Verify or Read and Verify, the tool returns a Fail in two different scenarios - when the read fails, or when the read is successful but does not match the text string entered in the Match String parameter.

In the latter case, when the Read and Verify Mode is selected, the tool outputs the mismatch data (Mismatch and Mismatch_Count) which can be used by the EasyView and other communication devices in the Communication Application Step. The mismatch data can be selected from the Select EasyView Items dialog, the Select OPC Tags dialog or the Select Input/Output Data dialog.

The mismatch data is useful when the user needs to determine if the tool is not able to read the text, or if the text can be read but does not match the defined Match String. For example, when the tool is not able to read the text, there might be an issue with the text printing process or the vision system setup. When the text is read successfully but does not match the defined Match String, the wrong text could be printed.

Font

Defines the font type. You can select a predefined font type (OCR-A or OCR-B, either white-on-black or black-on-white), or create a Custom font by training Character Models.

Note: You can use up to four custom fonts (for example, "Custom_1," "Custom_2," "Custom_3" and "Custom_4") within a single job.

Field String

Defines the number of characters contained in the text string for a Read operation. Each character in the Field String corresponds to an indexed position between 0 and 31 (the maximum number of characters). The number of positions in a Field String must be equal to the number of characters in the text string.

A Field String entry can include uppercase or lowercase text, numbers, dashes, dots and spaces. By default, each position in the Field String is represented as an "*" (an alphanumeric "Wildcard"), which means that any character is valid at that position in the text string.

Individual positions in the Field String can be defined, so the tool only considers a subset of possible characters at that position, increasing the tool's overall performance and reliability.

Field String Entry	Description	Valid Characters
*	Wildcard	Any trained character in the font.
N	Numeric	0123456789
A	Uppercase alphabetical	ABCDEFGHIJKLMNOPQRSTUVWXYZ
a	Lowercase alphabetical	abcdefghijklmnopqrstuvwxyz
H	Hexadecimal, uppercase alphabetical and numerical	0123456789ABCDEF
h	Hexadecimal, lowercase alphabetical and numerical	0123456789abcdef
O	Octal	01234567

Match String

Defines the expected text string to be read (only enabled when the Mode parameter is set to Verify or Read and Verify). Enter the information that you expect the tool to decode.

Note: The match string can be input from another device. When you run the job, the identification tool can read the text string from your input device and compare it to the recognized text. The Read Text tool will result in a Fail and the Match String field will display TRIG until the Match String is input from the external device.

Tune Button

Calculates the scale difference (50% to 200%) between the trained Character Models of the Font library versus the characters in the image. The Tune button should only be used when the difference between the size of the Character Models and the characters in the text string exceed ±5%.

Accept Threshold

Defines the minimum acceptable score (0-100; default = 70) for each character in the text string. If any character in the text string is below the Accept Threshold, the result of the entire text string will be a failure.

Read Mode

Defines the text reading algorithm mode: Speed or Accuracy. The Speed Mode (default Read Mode) is more effective when dealing with good, highly contrasted images that require a very fast tool execution time, while the Accuracy Mode is more effective when dealing with more difficult, lower contrasted images that do not require the tool to execute quickly.

Difference Accept

Defines the minimum acceptable difference value required between a character's highest and second-highest scores (0-20; default = 0). If a difference score is equal to or below the Difference Accept value, the result of the entire text string will be a failure.

Confusing Background

Compensates for extra features in the image being confused with the text string (by default, this option is Off, or unchecked). When Confusing Background is enabled, the tool's execution time is slightly increased. This option is especially useful when other features in the region are being mistaken for the beginning of the text string.

Scale Tolerance

Allows variations in character scale (by default, this option is Off, or unchecked).

Timeout

Defines the amount of time, in milliseconds (0 to 30,000), that the tool will search for text before execution is stopped and the tool returns a Fail.

Result

Displays the decoded or verified information from the text string.

Read Text Identification Tool - Settings Tab