ByteScout PDF Suite – C# – Set invisible text over image in pdf with pdf sdk

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ByteScout PDF Suite – C# – Set invisible text over image in pdf with pdf sdk

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ByteScout-PDF-Suite-C-sharp-Set-invisible-text-over-image-in-pdf-with-pdf-sdk.pdf

How to set invisible text over image in pdf with pdf sdk in C# with ByteScout PDF Suite

Learning is essential in computer world and the tutorial below will demonstrate how to set invisible text over image in pdf with pdf sdk in C#

ByteScout simple and easy to understand tutorials are planned to describe the code for both C# beginners and advanced programmers. 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 and you can use it to set invisible text over image in pdf with pdf sdk with C#.

This prolific sample source code in C# for ByteScout PDF Suite contains various functions and other necessary options you should do calling the API to set invisible text over image in pdf with pdf sdk. Just copy and paste the code into your C# application’s code and follow the instructions. Complete and detailed tutorials and documentation are available along with installed ByteScout PDF Suite if you’d like to learn more about the topic and the details of the API.

Our website gives trial version of ByteScout PDF Suite for free. It also includes documentation and source code samples.

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Program.cs

      using System.Diagnostics;
using Bytescout.PDF;

namespace InvisibleTextOverImage
{
    /// <summary>
    /// This example demonstrates how to create PDF document from scanned document image and add invisible text over it. 
    /// </summary>
    class Program
    {
        static void Main()
        {
            // Create new PDF document
            Document pdfDocument = new Document();
            pdfDocument.RegistrationName = "demo";
            pdfDocument.RegistrationKey = "demo";


            // Load image from file to System.Drawing.Image object (we need it to get the image resolution)
            System.Drawing.Image sysImage = System.Drawing.Image.FromFile(@".\scanned-invoice.png");
            // Compute image size in PDF units (Points)
            float widthInPoints = sysImage.Width / sysImage.HorizontalResolution * 72f;
            float heightInPoints = sysImage.Height / sysImage.VerticalResolution * 72f;

            // Create page of computed size
            Page page = new Page(widthInPoints, heightInPoints);
            // Add page to the document
            pdfDocument.Pages.Add(page);

            Canvas canvas = page.Canvas;

            // Create Bytescout.PDF.Image object from loaded image
            Image pdfImage = new Image(sysImage);
            // Draw the image
            canvas.DrawImage(pdfImage, 0, 0, widthInPoints, heightInPoints);

            // Dispose the System.Drawing.Image object to free resources
            sysImage.Dispose();

            // Create brush
            SolidBrush transparentBrush = new SolidBrush(new ColorGray(0));
            // ... and make it transparent
            transparentBrush.Opacity = 0;

            // Draw text with transparent brush
            Font font16 = new Font(StandardFonts.Helvetica, 16);
            canvas.DrawString("Your Company Name", font16, transparentBrush, 40, 40);
            // Draw another text
            Font font10 = new Font(StandardFonts.Helvetica, 10);
            canvas.DrawString("Your Address", font10, transparentBrush, 40, 80);

            
            // Save document to file
            pdfDocument.Save("result.pdf");

            // Cleanup 
            pdfDocument.Dispose();

            // Open result document in default associated application (for demo purpose)
            ProcessStartInfo processStartInfo = new ProcessStartInfo("result.pdf");
            processStartInfo.UseShellExecute = true;
            Process.Start(processStartInfo);
        }
    }
}