PDF To Image Converter for .NET

Winnovative PDF to Image Converter can be used in any type of .NET application to convert PDF pages to images. The integration with existing .NET applications is extremely easy and no installation is necessary. The downloaded archive contains the assembly for .NET and a demo application. The full C# source code for the demo application is available in the Samples folder. The converter produces .NET Image objects during conversion that you can save to image files or use for further processing. You can also customize the color space and resolution used during rasterization operation.

The main features of the PDF to Image Converter are enumerated below:

  • Convert PDF pages to images
  • Create thumbnails of the PDF pages
  • Customize the color space and resolution of generated images
  • Convert PDF pages to images in memory or to image files in a folder
  • Save the PDF pages images in various image formats
  • Support for password protected PDF documents
  • Convert to images only a range of PDF pages
  • Get the number of pages in a PDF document
  • Get the PDF document title, keywords, author and description
  • Does not require Adobe Reader or other third party tools
  • Support for .NET 4.0 framework and later
  • Documentation and C# samples for all the features

For a full description of the software you can check the Winnovative PDF to Image Converter for .NET web page.

C# Code Sample for PDF to Image Conversion

The code below was taken from the PDF to Image Converter demo application available for download in the PDF to Image converter archive. In this sample an instance of the PdfToImageConverter class is constructed and used to rasterize the PDF document pages to images.

private void btnConvertToImages_Click(object sender, EventArgs e)
{
    if (pdfFileTextBox.Text.Trim().Equals(String.Empty))
    {
        MessageBox.Show("Please choose a source PDF file", "Choose PDF file", MessageBoxButtons.OK);
        return;
    }

    // the source pdf file
    string pdfFileName = pdfFileTextBox.Text.Trim();

    // start page number
    int startPageNumber = int.Parse(textBoxStartPage.Text.Trim());
    // end page number
    // when it is 0 the conversion will continue up to the end of document
    int endPageNumber = 0;
    if (textBoxEndPage.Text.Trim() != String.Empty)
        endPageNumber = int.Parse(textBoxEndPage.Text.Trim());

    // create the converter object and set the user options
    PdfToImageConverter pdfToImageConverter = new PdfToImageConverter();

    pdfToImageConverter.LicenseKey = "0F5PX0tPX09fSVFPX0xOUU5NUUZGRkZfTw==";

    // set the color space of the resulted images
    pdfToImageConverter.ColorSpace = SelectedColorSpace();

    // set the resolution of the resulted images
    pdfToImageConverter.Resolution = int.Parse(textBoxResolution.Text);

    // the demo output directory
    string outputDirectory = Path.Combine(Application.StartupPath, @"DemoFiles\Output");

    Cursor = Cursors.WaitCursor;

    // set the handler to be called when a page was converted
    pdfToImageConverter.PageConvertedEvent += pdfToImageConverter_PageConvertedEvent;            
            
    try
    {
        // call the converter to raise the PageConvertedEvent event when a PDF page is converted
        // the pdfToImageConverter_PageConvertedEvent handler below will be executed for each converted PDF page
        pdfToImageConverter.ConvertPdfPagesToImageInEvent(pdfFileName, startPageNumber, endPageNumber);

        // Alternatively you can use the ConvertPdfPagesToImage() and ConvertPdfPagesToImageFile() methods
        // to convert the PDF pages to images in memory or to image files in a directory

        // uncomment the line below to convert PDF pages in memory to an array of PdfPageImage objects
        //PdfPageImage[] pdfPageImages = pdfToImageConverter.ConvertPdfPagesToImage(pdfFileName, startPageNumber, endPageNumber);

        // uncomment the lines below to convert PDF pages to image files in a directory
        //string outputDirectory = System.IO.Path.Combine(Application.StartupPath, @"DemoFiles\Output");
        //pdfToImageConverter.ConvertPdfPagesToImageFile(pdfFileName, startPageNumber, endPageNumber, outputDirectory, "pdfpage");
    }
    catch (Exception ex)
    {
        // The conversion failed
        MessageBox.Show(String.Format("An error occurred. {0}", ex.Message), "Error");
        return;
    }
    finally
    {
        // uninstall the event handler
        pdfToImageConverter.PageConvertedEvent -= pdfToImageConverter_PageConvertedEvent;

        Cursor = Cursors.Arrow;
    }

    try
    {
        System.Diagnostics.Process.Start(outputDirectory);
    }
    catch (Exception ex)
    {
        MessageBox.Show(string.Format("Cannot open output folder. {0}", ex.Message));
        return;
    }
}

/// <summary>
/// The PageConvertedEvent event handler called after when a PDF page was converted to image
/// The event is raised when the ConvertPdfPagesToImageInEvent() method is used
/// </summary>
/// <param name="args">The handler argument containing the PDF page image and page number</param>
void pdfToImageConverter_PageConvertedEvent(PageConvertedEventArgs args)
{
    // get the image object and page number from even handler argument
    Image pdfPageImageObj = args.PdfPageImage.ImageObject;
    int pageNumber = args.PdfPageImage.PageNumber;

    // save the PDF page image to a PNG file
    string outputPageImage = Path.Combine(Application.StartupPath, @"DemoFiles\Output", "pdfpage_" + pageNumber + ".png");
    pdfPageImageObj.Save(outputPageImage, ImageFormat.Png);

    args.PdfPageImage.Dispose();
}

 

 

Convert HTML to JPEG, PNG or BMP Images in ASP.NET Applications with C# and VB.NET

Winnovative HTML to Image Converter can be used in any type of .NET application to convert HTML pages to raster images and to create thumbnails of the HTML pages. The HTML to Image Converter is not a standalone product, it is part of the HTML to PDF Converter Library for .NET and is represented by the HtmlToImageConverter class of that library. Using this class you can convert HTML pages to any type of raster image supported by the .NET framework like BMP, JPEG, PNG or GIF. When converting to PNG you can also choose to produce an image with transparent background.

The code below was taken from the HTML to Image Converter demo application available for download in the HTML to PDF Converter product package. In this sample an instance of the HtmlToImageConverter class is constructed and used to rasterize the HTML page to an image.

protected void convertToImageButton_Click(object sender, EventArgs e)
{
    // Create a HTML to Image converter object with default settings
    HtmlToImageConverter htmlToImageConverter = new HtmlToImageConverter();

    // Set HTML Viewer width in pixels which is the equivalent in converter of the browser window width
    htmlToImageConverter.HtmlViewerWidth = int.Parse(htmlViewerWidthTextBox.Text);

    // Set HTML viewer height in pixels to convert the top part of a HTML page 
    // Leave it not set to convert the entire HTML
    if (htmlViewerHeightTextBox.Text.Length > 0)
        htmlToImageConverter.HtmlViewerHeight = int.Parse(htmlViewerHeightTextBox.Text);

    // Set if the created image has a transparent background
    htmlToImageConverter.TransparentBackground = SelectedImageFormat() == System.Drawing.Imaging.ImageFormat.Png ? transparentBackgroundCheckBox.Checked : false;

    // Set the maximum time in seconds to wait for HTML page to be loaded 
    // Leave it not set for a default 60 seconds maximum wait time
    htmlToImageConverter.NavigationTimeout = int.Parse(navigationTimeoutTextBox.Text);

    // Set an adddional delay in seconds to wait for JavaScript or AJAX calls after page load completed
    // Set this property to 0 if you don't need to wait for such asynchcronous operations to finish
    if (conversionDelayTextBox.Text.Length > 0)
        htmlToImageConverter.ConversionDelay = int.Parse(conversionDelayTextBox.Text);

    System.Drawing.Image[] imageTiles = null;

    if (convertUrlRadioButton.Checked)
    {
        string url = urlTextBox.Text;

        // Convert the HTML page given by an URL to a set of Image objects
        imageTiles = htmlToImageConverter.ConvertUrlToImageTiles(url);
    }
    else
    {
        string htmlString = htmlStringTextBox.Text;
        string baseUrl = baseUrlTextBox.Text;

        // Convert a HTML string with a base URL to a set of Image objects
        imageTiles = htmlToImageConverter.ConvertHtmlToImageTiles(htmlString, baseUrl);
    }

    // Save the first image tile to a memory buffer

    System.Drawing.Image outImage = imageTiles[0];

    // Create a memory stream where to save the image
    System.IO.MemoryStream imageOutputStream = new System.IO.MemoryStream();

    // Save the image to memory stream
    outImage.Save(imageOutputStream, SelectedImageFormat());

    // Write the memory stream to a memory buffer
    imageOutputStream.Position = 0;
    byte[] outImageBuffer = imageOutputStream.ToArray();

    // Close the output memory stream
    imageOutputStream.Close();

    // Send the image as response to browser

    string imageFormatName = imageFormatComboBox.SelectedValue.ToLower();

    // Set response content type
    Response.AddHeader("Content-Type", "image/" + (imageFormatName == "jpg" ? "jpeg" : imageFormatName));

    // Instruct the browser to open the image file as an attachment or inline
    Response.AddHeader("Content-Disposition", String.Format("attachment; filename={0}; size={1}", "HTML_to_Image." + imageFormatName, outImageBuffer.Length.ToString()));

    // Write the image buffer to HTTP response
    Response.BinaryWrite(outImageBuffer);

    // End the HTTP response and stop the current page processing
    Response.End();
}