Hough Lines

The 'Maximum Lines' property limits the number of lines returned by the detection algorithm.

• Increase for complex layouts with many lines.
• Decrease to focus on the most prominent lines and improve performance.

Tuning Guidance:

• Set based on the expected number of lines in your documents.
• If too low, some lines may be missed.

The 'Minimum Votes' property sets the threshold for how many supporting pixels are required for a line to be detected.

• Increase to detect only strong, well-defined lines.
• Decrease to detect faint or broken lines, but may increase false positives.

Tuning Guidance:

• Review the "Detected Lines" diagnostic to see which lines are included or excluded.

The 'Minimum Line Length' property specifies the shortest line segment (in unit-aware format, e.g. 1in) that will be considered for detection.

• Increase to ignore short or spurious lines.
• Decrease to detect small features or short lines.

Tuning Guidance:

• Set based on the scale of lines in your documents.
• Use unit-aware values (e.g. 0.5in, 10px).

The 'Maximum Line Gap' property sets the largest allowed gap (in unit-aware format) between segments to be considered a single line.

• Increase to merge broken or dashed lines.
• Decrease to keep lines separate.

Tuning Guidance:

• Adjust to match the continuity of lines in your documents.

The 'Delta' property determines the resolution of the Hough Transform's distance parameter.

• Lower values increase precision but may increase processing time.
• Higher values speed up processing but may miss closely spaced lines.

Tuning Guidance:

• Use the default unless you have specific requirements for line spacing.

The 'Angle Precision' property sets the angular resolution (in degrees) for line detection.

• Lower values detect lines at more precise angles.
• Higher values group similar angles together.

Tuning Guidance:

• Use finer precision for documents with lines at many different angles.

The 'Border Size' property defines a margin (in unit-aware format) around the page where lines will not be detected.

• Increase to avoid detecting lines at the very edge of the page.
• Decrease to include edge lines.

Tuning Guidance:

• Use to avoid false positives from page borders or scanning artifacts.

The 'Binarization Settings' property defines how the input image is converted to black and white before line detection. Proper binarization is critical for accurate line detection, especially on noisy or low-contrast images.

• Configure to match the quality and type of your documents.
• Use adaptive or auto binarization for variable backgrounds.

Tuning Guidance:

• Review the "Bin Image" diagnostic to ensure lines are preserved and noise is minimized.

A combination of the following flags:

The 'Line Types' property filters detected lines by their orientation.

• Select horizontal, vertical, and/or non-square angles as needed.

Tuning Guidance:

• Use to focus detection on lines relevant to your workflow (e.g., only table borders).

The 'Square Angle Tolerance' property sets the maximum angular deviation (in degrees) for a line to be considered horizontal or vertical.

• Lower values require lines to be more perfectly aligned.
• Higher values allow for skewed or imperfect lines.

Tuning Guidance:

• Only applies when filtering for horizontal or vertical lines.

The 'Merge Duplicate Lines' property enables post-processing to combine overlapping or nearly identical lines.

• Enable to reduce duplicate or fragmented lines.
• Disable to keep all detected lines separate.

Tuning Guidance:

• Use in documents where lines may be broken or repeated.

The 'Angle Tolerance' property sets the maximum allowed angular difference (in degrees) for two lines to be merged.

• Lower values require lines to be nearly parallel.
• Higher values allow merging of lines with greater angular difference.

Tuning Guidance:

• Only applies when 'Merge Duplicate Lines' is enabled.

The 'Distance Tolerance' property sets the maximum allowed distance (in unit-aware format) for two lines to be merged.

• Lower values require lines to be very close together.
• Higher values allow merging of lines that are farther apart.

Tuning Guidance:

• Only applies when 'Merge Duplicate Lines' is enabled.

The 'Command Type Name' property shows the user-friendly name of the IP Command as it appears in the Grooper UI. This helps users identify which command is being configured or executed, especially when working with IP Profiles containing multiple commands.

This property is read-only and is automatically set based on the command's type.

The 'Supported Pixel Formats' property lists the image pixel formats that the IP Command can process. If an image does not match one of these formats, the command will be skipped for that image.

• By default, all pixel formats are supported unless a derived command restricts this list.
• Example formats include Pixel8bppGrayscale, Pixel24bppBgr, and Pixel1bppIndexed.

Use this property to verify compatibility when building IP Profiles or troubleshooting why a command did not execute.