Read Controls dialog

In the ScanTools Application module window, you select the level of read control available to the application user by selecting Read Controls from the Options menu. The Read Controls dialog box appears. See also Scanner Read Levels for a list of values used by some of these parameters.

NOTE: The options set in this dialog box may not be applicable to the scanner that is controlled by this application. Refer to the scanner user guide for more information about the capabilities of the scanner.

Mark Threshold

The mark threshold is how dark a mark must be on a form before the scanner detects it. In these fields, you can specify the mark threshold separately for Bubble Marks, Check Marks, and Tick Marks.

• Bubble Mark - an approximately round response area (circle or oval). The round area is filled in to indicate a response.
• Check Mark(For Image Scanner Implementation Only) - an approximately square response area where an X, check, or other mark indicates a response. This style is an image feature and requires OMR From Image and Enable Image to be set in the Application Settings dialog for the side of the sheet where the grid is located.
• Tick Mark (For Image Scanner Implementation Only) - a rectangular response area approximately as wide as a normal OMR position, but only as high as a thick pencil mark. A single horizontal stroke indicates a response. Also known as line read. This style is an image feature and requires OMR From Image and Enable Image to be set in the Application Settings dialog for the side of the sheet where the grid is located.

Keyword Settings

The keyword settings available are:

• Light causes ScanTools to accept very light marks.
• Normal is the setting to use for most normal scanning tasks.
• Dark causes ScanTools to accept only very heavy marks.

Absolute Value Settings

Absolute values of 3 - 10 are available in addition to the keyword values. The mark threshold control is enabled in application definition only when the Scan Time Read Parameters Control (below) is set to None.

Discrimination Margin

The discrimination margin is the degree of difference in darkness that is permitted for valid marks.

• For Image Scanner Implementation Only: In these fields, you can specify the discrimination margin separately for Bubble Marks, Check Marks, and Tick Marks.
• For EZData Scanners: This setting is NOT used by the EZData scanner.

The keyword settings available are:

• Low causes ScanTools to pick one mark over another, even if they are very similar.
• Medium balances picking one mark over another based on their differences, without requiring moderate differen Medium is the setting to use for most normal scanning tasks.tasks.
• High causes ScanTools to pick one mark over another only if they differ significantly.

Absolute values of 3 - 15 are available in addition to the keyword values. The discrimination margin control is enabled in application definition only when the Scan Time Read Parameters Control (below) is set to None.

Mark Discrimination Cutoff

If any of the marks are above the value set by this counter, no discrimination is done between marks and a multiple is the result.

Valid values are 10 - 15.

For EZData Scanners: This setting is NOT used by the EZData scanner.

Form ID/Litho-code Threshold

This counter controls how dark a form ID or litho-code mark must be to be considered valid. All form ID marks and litho-code marks below this value will be ignored. Valid values are 6 - 10.

Scan Time Read Parameters Control

About Read Parameters Controls

Read parameter controls are located in both the Read Controls dialog and the Read Parameters section of the Scanning Options dialog. The controls provided in these two dialogs are similar and they are, in fact, interrelated. The key considerations regarding how they work together are:

• Read Controls are set during application development only. They enable the application developer to either set the read parameters and/or to define how much control the application user has over read parameters at scan-time.
• Scanning Options, including Read Parameters, are available during application development and at scan-time:
• When accessed from the Application Module during application development, they enable the application developer to set the initial scan-time read parameters for the application user.
• When accessed from the Main Window at scan-time, they enable the application user to set scan-time read parameters to whatever degree (Keyword or Absolute) allowed by the developer.

At scanning time, using the Scanning Options dialog box, you can allow the operator to change the Mark Threshold and Discrimination Margin, if you select a value other than None.

None

Select this to specify no read level control at scanning time. The values defined in the application for Mark Threshold and Discrimination Margin (above) are used at scanning time and the scanner operator CANNOT change them in the Scanning Options at scanning time.

Keyword Level Control

Select this to specify keyword values (such as light, normal, dark, and low, medium, high) for the Mark Threshold and Discrimination Margin at scanning time, using the Scanning Options dialog.

Absolute Level Control

Select this to specify hexadecimal values for the Mark Threshold and Discrimination Margin at scanning time, using the Scanning Options dialog.