Added new kb article signature-resize-signature-pdf

knowledge-base/signature-resize-signature-pdf.md

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+---
+title: Resizing a Signature in PDF
+description: Learn how to resize a signature before appending it to a PDF document.
+type: how-to
+page_title: Resize a Signature in PDF | RadSignature for ASP.NET AJAX | Telerik
+slug: signature-resize-signature-pdf
+tags: pdf, signature, resize, RadSignature, ASP.NET AJAX
+res_type: kb
+---
+# Environment
+| Product   | RadSignature for ASP.NET AJAX |
+|-----------|------------------------------|
+| Version   | all                 |
+
+# Description
+I want to resize a signature in a PDF document using RadSignature for ASP.NET AJAX. I have code that places the signature in the PDF, but I'm not able to resize it to a smaller size to fit it in the form.
+
+# Solution
+The solution is based on the [Signing Pdf Documents demo](https://demos.telerik.com/aspnet-ajax/signature/applicationscenarios/signingpdfdocuments/defaultcs.aspx). To resize the signature in the PDF document, you can modify the code as follows:
+
+Before translating the position of the `foregroundContentOwner`, apply a scaling transformation to resize it. Choose the scaling factors (width and height) based on your requirements.
+
+````CS
+using (pageWriter.SaveContentPosition())
+{
+    // Scale the signature
+    double scaleX = 0.3; // Example scaling factor for width
+    double scaleY = 0.3; // Example scaling factor for height
+    pageWriter.ContentPosition.Scale(scaleX, scaleY);
+
+    // Adjust the translation values
+    double xCenteringTranslation = ((pageSource.Size.Width - (foregroundContentOwner.Size.Width * scaleX)) - 120) / 2;
+    double yCenteringTranslation = ((pageSource.Size.Height - (foregroundContentOwner.Size.Height * scaleY)) - 110);
+
+    pageWriter.ContentPosition.Translate(xCenteringTranslation, yCenteringTranslation);
+    pageWriter.WriteContent(foregroundContentOwner);
+}
+````
+This modified code will scale the signature and adjust its position to fit it within the PDF document. The example scaling factors used are `0.3` for both width and height. Adjust these values according to your requirements.
+
+````CS
+using System;
+using System.Drawing;
+using System.Drawing.Imaging;
+using System.IO;
+using System.Web.UI;
+using System.Windows;
+using Telerik.Web.UI;
+using Telerik.Windows.Documents.Fixed;
+using Telerik.Windows.Documents.Fixed.FormatProviders.Pdf;
+using Telerik.Windows.Documents.Fixed.FormatProviders.Pdf.Streaming;
+using Telerik.Windows.Documents.Fixed.Model;
+using Telerik.Windows.Documents.Fixed.Model.Data;
+using Telerik.Windows.Documents.Fixed.Model.Editing;
+
+namespace Telerik.Web.Examples.Signature.SigningPdfDocuments
+{
+    public partial class DefaultCS : System.Web.UI.Page
+    {
+        protected void RadAjaxManager1_AjaxRequest(object sender, Telerik.Web.UI.AjaxRequestEventArgs e)
+        {
+            var fileName = e.Argument.Split(';')[0];
+            var base64 = e.Argument.Split(',')[1];
+
+            RadPdfViewer1.PdfjsProcessingSettings.FileSettings.Data = PreparePdf(base64);
+        }
+
+
+        public string PreparePdf(string pdfData)
+        {
+            byte[] resultingBytes = null;
+            byte[] finalBytes = null;
+
+            PdfFormatProvider provider = new PdfFormatProvider();
+            byte[] renderedBytes = Convert.FromBase64String(pdfData);
+
+            RadFixedDocument document1 = null;
+            RadFixedDocument document2 = provider.Import(renderedBytes);
+
+            string filePath = Server.MapPath("Documents/Document.pdf");
+
+            using (FileStream input = new FileStream(filePath, FileMode.Open, FileAccess.Read))
+            {
+                document1 = provider.Import(input);
+            }
+
+            using (MemoryStream ms = new MemoryStream())
+            {
+                provider.Export(document1, ms);
+                resultingBytes = ms.ToArray();
+            }
+
+            finalBytes = AppendContent(resultingBytes, document2);
+            string result = Convert.ToBase64String(finalBytes);
+
+            return result;
+        }
+        private byte[] AppendContent(byte[] resultingBytes, RadFixedDocument document2)
+        {
+            RadFixedPage foregroundContentOwner = document2.Pages[0];
+
+            MemoryStream ms = new MemoryStream();
+            byte[] renderedBytes = null;
+            using (MemoryStream stream = new MemoryStream(resultingBytes))
+            {
+                using (PdfFileSource fileSource = new PdfFileSource(stream))
+                {
+                    using (PdfStreamWriter fileWriter = new PdfStreamWriter(ms, true))
+                    {
+                        foreach (PdfPageSource pageSource in fileSource.Pages)
+                        {
+                            using (PdfPageStreamWriter pageWriter = fileWriter.BeginPage(pageSource.Size, pageSource.Rotation))
+                            {
+                                pageWriter.WriteContent(pageSource);
+
+                                using (pageWriter.SaveContentPosition())
+                                {
+                                    // Scale the signature
+                                    double scaleX = 0.3; // Example scaling factor for width
+                                    double scaleY = 0.3; // Example scaling factor for height
+                                    pageWriter.ContentPosition.Scale(scaleX, scaleY);
+
+                                    // Adjust the translation values
+                                    double xCenteringTranslation = ((pageSource.Size.Width - (foregroundContentOwner.Size.Width * scaleX)) - 120) / 2;
+                                    double yCenteringTranslation = ((pageSource.Size.Height - (foregroundContentOwner.Size.Height * scaleY)) - 110);
+
+                                    pageWriter.ContentPosition.Translate(xCenteringTranslation, yCenteringTranslation);
+                                    pageWriter.WriteContent(foregroundContentOwner);
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+            renderedBytes = ms.ToArray();
+            return renderedBytes;
+        }
+
+        protected void Page_PreRender(object sender, EventArgs e)
+        {
+            RadSkinManager.GetCurrent(Page).Skin = "Silk";
+        }
+    }
+}
+````
+
+# Notes
+- Ensure that you have the latest version of RadSignature for ASP.NET AJAX.
+- Adjust the scaling factors (`scaleX` and `scaleY`) according to your requirements to resize the signature.
+- Modify the translation values (`xCenteringTranslation` and `yCenteringTranslation`) to adjust the position of the signature after scaling.
+- This solution is based on the Signing PDF Documents demo and may require additional modifications to fit your implementation.
+
+# See Also
+- [RadSignature for ASP.NET AJAX Documentation](https://docs.telerik.com/devtools/aspnet-ajax/controls/signature/overview)
+- [Signing PDF Documents Demo](https://demos.telerik.com/aspnet-ajax/signature/examples/signingpdfdocuments/defaultcs.aspx)