Imaging Library

Description

PCL Imaging Library especially designed for document scanning like Office Lens and Camscanner. It contains some filters to achieve this. (Canny edge detection, Blob counter, quadrilateral transformation, etc..)

Supporting Platforms

Compatible .net platforms: net45 + dnxcore50 + win8 + Xamarin.Android + Xamarin.iOS + Xamarin.Mac

Nuget Package

Install-Package Imaging.Library https://www.nuget.org/packages/Imaging.Library

Code Sample

    var imaging = new ImagingManager(source);       //source is PixelMap, you can find samples how to convert image to PixelMap
    imaging.AddFilter(new BicubicFilter(scale));    //Downscaling
    imaging.AddFilter(new CannyEdgeDetector());     //This filter contains Grayscale and Gaussian filter in it
    imaging.Render();                               //Renders the image to use it further use

    var blobCounter = new BlobCounter()
    {
        ObjectsOrder = ObjectsOrder.Size
    };
    imaging.AddFilter(blobCounter);

    imaging.Render();

    //Following code finds largest quadratical blob
    List<Imaging.Library.Entities.Point> corners = null;
    var blobs = blobCounter.GetObjectsInformation();
    foreach (var blob in blobs)
    {
        var points = blobCounter.GetBlobsEdgePoints(blob);

        var shapeChecker = new SimpleShapeChecker();

        if (shapeChecker.IsQuadrilateral(points, out corners))
            break;
    }

    imaging.UndoAll();                              //Undo every filters applied

    var edgePoints = new EdgePoints();
    edgePoints.SetPoints(corners.ToArray());
    edgePoints = edgePoints.ZoomIn(scale);          //Corrects points that found on downscaled image to original
    imaging.AddFilter(new QuadrilateralTransformation(edgePoints, true));

    imaging.Render();

    //imaging.Output gives that extracted rectangle shape from photo. Check out WPF sample how to save it.

Sample Scanning

Original Output
alt source alt output

Sample Projects

  • WPF
    • EdgeDetection
  • Xamarin
    • EdgeDetection.Android
    • EdgeDetection.Forms
      • EdgeDetection.Forms (Portable)
      • EdgeDetection.Forms.Android
      • EdgeDetection.Forms.iOS

Note: You can find AndroidHelper.cs and iOSHelper.cs in EdgeDetection.Forms (Portable) which are convert platform specific bitmap from/to PixelMap.