Currently I am using iText7 version 8.0.4 to replace jpg files into svg files.

I replaced the jpg image with the svg image but the problem is that the font in my 2nd screenshot is wrong, the font I used in the svg file is “Lucida Console” but when I replace the svg file it changes to the font. “Time New Roman”. When the svg file is saved on my computer it still displays correctly, it’s just the wrong font when I add it to the pdf

This’s my .net code:

public bool ReplaceImageWithSvg(string inputPdf, string outputPdf)
{
    try
    {
        using (PdfReader pdfReader = new PdfReader(inputPdf))
        using (PdfWriter pdfWriter = new PdfWriter(outputPdf))
        using (PdfDocument pdfDocument = new PdfDocument(pdfReader, pdfWriter))
        {
            int numPages = pdfDocument.GetNumberOfPages();
            string tempPath = System.IO.Path.GetTempPath();

            for (int pageNum = 1; pageNum <= numPages; pageNum++)
            {
                PdfPage page = pdfDocument.GetPage(pageNum);

                IList<PdfAnnotation> annotations = new List<PdfAnnotation>(page.GetAnnotations());

                foreach (PdfAnnotation annotation in annotations)
                {
                    if (annotation.GetSubtype().Equals(PdfName.Link))
                    {
                        PdfLinkAnnotation linkAnnotation = (PdfLinkAnnotation)annotation;

                        // Check if the link annotation is associated with an image
                        PdfArray rect = linkAnnotation.GetRectangle();
                        if (rect != null && rect.Size() == 4)
                        {
                            var tempSvgFile = System.IO.Path.Combine(tempPath, Guid.NewGuid().ToString() + ".svg");
                            var imageUrl = ExtractURL(linkAnnotation.GetAction().ToString());

                            var svgContent = FetchSvgImageAsync(imageUrl);

                            var imageStream = ModifySvgFontAttributes(svgContent, _newFontFamily, _increaseFontSizeBy, _increaseFontWeight, _newStrokeWidth);

                            SaveSvgToFile(imageStream, tempSvgFile);

                            ReplaceImageWithSvg(page, rect, tempSvgFile);

                            page.RemoveAnnotation(linkAnnotation);

                            if (File.Exists(tempSvgFile))
                            {
                                File.Delete(tempSvgFile);
                            }
                        }
                    }
                }
            }
        }

        return true;
    }
    catch (Exception ex)
    {
        Console.WriteLine($"Error replacing image with SVG: {ex.Message}");
        return false;
    }
}

private void ReplaceImageWithSvg(PdfPage page, PdfArray rect, string svgImagePath)
{
    try
    {
        // Extract position and dimensions of the existing image
        float x = rect.GetAsNumber(0).FloatValue();
        float y = rect.GetAsNumber(1).FloatValue();
        // Added on to get rid of the border
        float width = rect.GetAsNumber(2).FloatValue() - x + _border;
        float height = rect.GetAsNumber(3).FloatValue() - y + _border;


        // Convert the SVG image to PdfFormXObject
        PdfDocument pdfDoc = page.GetDocument();
        using (Stream svgStream = File.OpenRead(svgImagePath))
        {
            PdfFormXObject svgObject = SvgConverter.ConvertToXObject(svgStream, pdfDoc);

            // Get the content stream of the page
            PdfCanvas canvas = new PdfCanvas(page);
            // Set fill color to white(or match the page background)
            canvas.SetFillColorGray(1.0f); // White color
            // Cover the area with a rectangle
            canvas.Rectangle(x, y, width, height);
            canvas.Fill();

            // Calculate the scale to fit the SVG in the specified rectangle
            // Assumes the SVG's aspect ratio matches the target rectangle.
            float scaleX = width / svgObject.GetWidth();
            float scaleY = height / svgObject.GetHeight();

            // Create transformation matrix for scaling and then translating the image
            float[] matrix = new float[] { scaleX, 0, 0, scaleY, x, y };

            // Add the SVG Form XObject to the canvas with transformation
            canvas.AddXObjectWithTransformationMatrix(svgObject, matrix[0], matrix[1], matrix[2], matrix[3], matrix[4], matrix[5]);
        }
    }
    catch (Exception ex)
    {
        Console.WriteLine($"Error replacing image with SVG: {ex.Message}");
    }
}

private string ModifySvgFontAttributes(string svgContent, string newFontFamily, string fontSizeIncrease, int fontWeightIncrease, string strokeWidth)
{
    XDocument svgDoc = XDocument.Parse(svgContent);

    // Update font-family
    var elementsWithFontFamily = svgDoc.Descendants().Where(e => e.Attribute("font-family") != null);
    foreach (var elem in elementsWithFontFamily)
    {
        elem.SetAttributeValue("font-family", newFontFamily);
    }

    return svgDoc.ToString();
}