Projection Profile

Computes projection profiles to analyze the distribution of pixel intensities along the X and Y axes of an image.

Remarks

The Projection Profile command generates horizontal and vertical projection profiles, which are histograms showing the sum of pixel intensities along each row and column of an image. Projection profiles are a fundamental tool for layout analysis, margin detection, and diagnosing structural characteristics of scanned pages.

Projection profiles are commonly used to:

• Detect the presence and position of text lines, graphics, or other features.
• Support layout analysis, such as finding document margins or segmenting regions.
• Diagnose skew, alignment, or other structural characteristics of scanned pages.

How It Works

1. The input image is converted to grayscale if necessary.
2. The command computes the sum of pixel intensities for each row (horizontal profile) and each column (vertical profile).
3. Optional post-processing can be applied, including inversion, scaling, and running average smoothing.
4. The resulting profiles can be visualized in diagnostic mode or used by downstream processes for further analysis.

Supported Pixel Formats

• All basic pixel formats are supported, including 8-bit and 16-bit grayscale, and 24-bit color. Images are automatically converted to grayscale as needed.

Diagnostics

When diagnostic mode is enabled, Projection Profile generates a diagnostic image visualizing the projection profiles alongside the original image. This helps users understand the distribution of content and tune configuration parameters for margin detection, segmentation, or skew correction.

Classification Features

This command does not directly produce classification features, but the computed projection data can be used by downstream processes for feature extraction, layout analysis, or document classification.

Configuration Guidance

• Use the 'Preview Size (inches)' property to control the size of the diagnostic preview region.
• Use the 'Running Average (inches)' property to smooth the projection profile and reduce noise.
• For most users, direct use of this command is not necessary; instead, rely on higher-level commands that leverage projection profiles automatically.

Properties

Name	Type		Description
General
Preview Size (inches)	Double	►	Sets the size, in inches, of the preview region used when generating a diagnostic projection profile image. Default2 The 'Preview Size (inches)' property controls the width and height of the preview area displayed in diagnostic images. This does not affect the underlying projection profile calculation, but only the visualization shown in diagnostics. Increase this value for higher-resolution previews, which can help when analyzing fine details or large images. Decrease for a more compact display, which may be useful for quick overviews or when working with small images. Example: Set to 2.0 for a 2-inch preview region.
Running Average (inches)	Double	►	Specifies the length, in inches, of the running average window applied to the projection profile. Default0 The 'Running Average (inches)' property applies smoothing to the projection profile by averaging values over the specified window size. Smoothing can help reduce noise and highlight broader trends in the projection data. Use a larger value to reduce noise and emphasize major features, such as large text blocks or graphics. Use a smaller value to preserve fine detail, which may be important for detecting small features or closely spaced lines. Set to 0 to disable averaging and use raw projection data. Example: Set to 0.25 to apply a running average over a 0.25-inch window.
Command Info
Command Type	String	►	The display name of this image processing command. 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.
Supported Pixel Formats	String	►	The pixel formats supported by this command. 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.

Used By

IP Step