ECoding.InkAnchor 1.0.0

ECoding.InkAnchor

ECoding.InkAnchor is a versatile .NET 9 library designed to easily generate and analyze customizable anchor boxes using ArUco markers. It enables structured image generation, automated extraction, and evaluation of image content.

Key Features

• Anchor Box Generation: Create raster or SVG images containing labeled and customizable anchor boxes defined by ArUco markers.
• Marker Detection and Extraction: Efficiently detect anchor boxes from scanned images and extract content between ArUco markers.
• Content Evaluation: Measure the filled area percentage within extracted image sections, ideal for automated processing of handwritten or marked content.

Installation

Install the library easily via NuGet:

dotnet add package ECoding.InkAnchor

Usage

Generating Anchor Box Images

var options = new InkAnchorGeneratorOptions(boxId: 1, pixelWidth: 400, pixelHeight: 200)
{
    FillColor = Color.White,
    Border = new InkAnchorBorder(Color.Black, thickness: 2, borderStyle: InkAnchorBorder.BorderStyle.Dashed),
    BoxLabel = new InkAnchorLabel("Signature Box", BoxLabelPlacement.TopOutsideBox, fontSize: 14, color: Color.Black)
};

var image = await InkAnchorHandler.GenerateAnchorBoxImageAsync(options);
await image.SaveAsync("anchor_box.png");

Generating SVG Anchor Boxes

var svgContent = await InkAnchorHandler.GenerateAnchorBoxSvgAsync(options);
await File.WriteAllTextAsync("anchor_box.svg", svgContent);

Detecting and Extracting Boxes from Images

using var inputImage = Image.Load<Rgba32>("scanned_page.png");
var extractedBoxes = InkAnchorHandler.GetAnchorBoxesContentImage(inputImage);

foreach (var (boxId, croppedImage) in extractedBoxes)
{
    await croppedImage.SaveAsync($"extracted_box_{boxId}.png");
}

Evaluating Filled Area Percentage

using var croppedImage = Image.Load<Rgba32>("extracted_box.png");
double filledPercentage = InkAnchorHandler.GetFilledAreaPercentage(croppedImage, brightnessThreshold: 225);
Console.WriteLine($"Filled Area: {filledPercentage * 100:0.##}%");

Configuration Options

InkAnchorGeneratorOptions

• BoxId (byte): Unique identifier for the anchor box.
• PixelWidth/PixelHeight (int): Dimensions of the box, minimum 30 pixels.
• MarkerPixelSize (int): Pixel size of ArUco markers, default is 60 px.
• MarkerBorderBits (int): Border bits around markers, default 1.
• MarkerPadding (int): Padding between marker and box border, default 1.
• FillColor (Color?): Background color, default transparent.
• Border (InkAnchorBorder?): Border styling and settings.
• BoxLabel (InkAnchorLabel?): Label text, placement, and styling.

InkAnchorBorder

Customize borders using:

• Color: Border color.
• Thickness: 1-5 pixels.
• Style: Solid, Dashed, Dotted.
• Sides: Top, Right, Bottom, Left, All.

InkAnchorLabel

Configure labels with:

• LabelText: Text for the label (max 100 characters).
• Color: Text color.
• FontSize: Between 5 and 25 pixels.
• Font: Font family.
• LabelPlacement: Top or Bottom outside the box.

Contributing

Contributions, feature requests, and bug reports are welcome! Please create an issue or submit a pull request on GitHub.

License

Licensed under the MIT License.

Dependencies

• SixLabors.ImageSharp
• OpenCvSharp

Acknowledgments

Thanks to the authors and maintainers of SixLabors.ImageSharp and OpenCvSharp for enabling powerful imaging and vision processing capabilities in .NET.