ByteScout PDF Suite – VB.NET – Slice PDF by horizontal lines inside

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ByteScout PDF Suite – VB.NET – Slice PDF by horizontal lines inside

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ByteScout-PDF-Suite-VB-NET-Slice-PDF-by-horizontal-lines-inside.pdf

slice PDF by horizontal lines inside in VB.NET using ByteScout PDF Suite

Build slice PDF by horizontal lines inside in VB.NET

Step-by-step instructions on how to do slice PDF by horizontal lines inside in VB.NET

We regularly create and update our sample code library so you may quickly learn slice PDF by horizontal lines inside and the step-by-step process in VB.NET. ByteScout PDF Suite was made to help with slice PDF by horizontal lines inside in VB.NET. ByteScout PDF Suite is the bundle that provides six different SDK libraries to work with PDF from generating rich PDF reports to extracting data from PDF documents and converting them to HTML. This bundle includes PDF (Generator) SDK, PDF Renderer SDK, PDF Extractor SDK, PDF to HTML SDK, PDF Viewer SDK and PDF Generator SDK for Javascript.

Save time on writing and testing code by using the code below and use it in your application. If you want to know how it works, then this VB.NET sample code should be copied and pasted into your application’s code editor. Then just compile and run it. These VB.NET sample examples can be used in one or many applications.

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Module1.vb

      Imports System.Drawing
Imports System.IO
Imports Bytescout.PDFExtractor
Imports Bytescout.PDFRenderer
Imports Bytescout.PDF

''' <summary>
''' The example demonstrates slicing of PDF document pages by horizontal lines.
''' The example uses three products:
''' - PDF Extractor SDK (https://bytescout.com/products/developer/pdfextractorsdk/index.html) -
'''     to detect lines;
''' - PDF Renderer SDK (https://bytescout.com/products/developer/pdfrenderersdk/index.html) -
'''     to render PDF documents to raster images;
''' - PDF SDK (https://bytescout.com/products/developer/pdfsdk/index.html) -
'''     to create new PDF documentsd from sliced images.
''' </summary>
Module Module1

    Dim InputFile = ".\sample.pdf"
    Dim OutputFolder = ".\output"

    Sub Main()

        if Not Directory.Exists(OutputFolder)
            Directory.CreateDirectory(OutputFolder)
        End If

        ' Create LineDetector instance and load document
        Dim lineDetector = new LineDetector("demo", "demo")
        lineDetector.LoadDocumentFromFile(InputFile)

        ' Create RasterRenderer instance and load document
        Dim rasterRenderer = new RasterRenderer("demo", "demo")
        rasterRenderer.LoadDocumentFromFile(InputFile)

        Try
            Dim pageCount = lineDetector.GetPageCount()

            For pageIndex As Integer = 0 To pageCount - 1
                
                Console.WriteLine("Processing page #{0}", pageIndex)

                ' Find horizontal lines on the page
                Dim horzLines = lineDetector.FindLines(pageIndex, LineOrientationsToFind.OnlyHorizontal)
                ' Slice page by separating lines and create new PDF documents
                Slice(pageIndex, horzLines, rasterRenderer)

            Next
        Catch exception As Exception
            Console.WriteLine(exception)
        Finally
            ' Cleanup
            rasterRenderer.Dispose()
            lineDetector.Dispose()
        End Try


        Console.WriteLine()
        Console.WriteLine("Press any key...")
        Console.ReadKey()
        
    End Sub


    Private Sub Slice(pageIndex As Integer, lines As FoundLinesCollection, rasterRenderer As RasterRenderer)
        
        Const pdfRenderingResolution As Single = 300
        Dim lastLineY As Single = Single.NaN
        Dim sliceNum as Integer = 0

        Dim pageRect = rasterRenderer.GetPageRectangle(pageIndex)

        For Each line As FoundLine In lines
            
            If Single.IsNaN(lastLineY)
                lastLineY = line.From.Y
            Else 
                ' Compute slice rectangle
                Dim sliceRect = new RectangleF(0, lastLineY, pageRect.Width, line.From.Y - lastLineY)
                ' Set extraction rectangle for RasterRenderer
                rasterRenderer.SetExtractionArea(sliceRect)
                ' Render the page region to Image object
                Dim slice = rasterRenderer.GetImage(pageIndex, pdfRenderingResolution)

                ' Create PDF document
                Dim document = new Document With {
                    .RegistrationName = "demo",
                    .RegistrationKey = "demo"
                }

                ' Create page of A4 size
                Dim page = new Page(PaperFormat.A4)
                document.Pages.Add(page)

                ' Create PDF Image object from System.Drawing.Image
                Dim pdfImage = new Bytescout.PDF.Image(slice)
                ' Draw image on the page keeping the aspect ratio
                Dim r = new RectangleF(0, 20, page.Width, page.Width / slice.Width * slice.Height)
                page.Canvas.DrawImage(pdfImage, r.Left, r.Top, r.Width, r.Height)

                ' Save PDF document
                sliceNum = sliceNum + 1
                Dim fileName = string.Format("{0}\{1}-page{2}-slice{3}.pdf", OutputFolder, IO.Path.GetFileName(InputFile), pageIndex, sliceNum)
                document.Save(fileName)

                Console.WriteLine("Saved slice '{0}'", fileName)

                ' Cleanup
                document.Dispose()
                slice.Dispose()

                lastLineY = line.From.Y

            End If
        Next

    End Sub
End Module