Convert PowerPoint Presentation to Image in Azure Functions v4

14 Sep 20246 minutes to read

Syncfusion PowerPoint is a .NET Core PowerPoint library used to create, read, edit and convert PowerPoint documents programmatically without Microsoft PowerPoint or interop dependencies. Using this library, you can convert a PowerPoint Presentation to image in Azure Functions v4.

Steps to convert a PowerPoint Presentation to Image in Azure Functions v4

Step 1: Create a new Azure Functions project.

Step 2: Create a project name and select the location.

Step 3: Select function worker as .NET 8.0 (Long Term Support).

Step 4: Install the Syncfusion.PresentationRenderer.Net.Core NuGet package as a reference to your project from NuGet.org.

NOTE

Starting with v16.2.0.x, if you reference Syncfusion assemblies from trial setup or from the NuGet feed, you also have to add “Syncfusion.Licensing” assembly reference and include a license key in your projects. Please refer to this link to know about registering Syncfusion license key in your application to use our components.

Step 5: Include the following namespaces in the Function1.cs file.

C#

using Syncfusion.Presentation;
using Syncfusion.PresentationRenderer;

Step 6: Add the following code snippet in Run method of Function1 class to perform PowerPoint Presentation to image conversion in Azure Functions and return the resultant image to client end.

C#

//Gets the input PowerPoint document as stream from request.
Stream stream = req.Content.ReadAsStreamAsync().Result;
//Loads an existing PowerPoint document
using (IPresentation pptxDoc = Presentation.Open(stream))
{
    //Initialize the PresentationRenderer to perform image conversion.
    pptxDoc.PresentationRenderer = new PresentationRenderer();
    //Convert PowerPoint slide to image as stream.
    Stream imageStream = pptxDoc.Slides[0].ConvertToImage(ExportImageFormat.Png);
    //Reset the stream position.
    imageStream.Position = 0;
    // Create a new memory stream.
    MemoryStream memoryStream = new MemoryStream();
    // Copy the contents of the image stream to the memory stream.
    imageStream.CopyTo(memoryStream);
    //Reset the stream position.
    memoryStream.Position = 0;
    //Create the response to return.
    HttpResponseMessage response = new HttpResponseMessage(HttpStatusCode.OK);
    //Set the image document saved stream as content of response.
    response.Content = new ByteArrayContent(memoryStream.ToArray());
    //Set the contentDisposition as attachment.
    response.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment")
    {
        FileName = "PPTXtoImage.jpeg"
    };
    //Set the content type as image mime type.
    response.Content.Headers.ContentType = new System.Net.Http.Headers.MediaTypeHeaderValue("application/jpeg");
    //Return the response with output image stream.
    return response;

Step 7: Right click the project and select Publish. Then, create a new profile in the Publish Window.

Step 8: Select the target as Azure and click Next button.

Step 9: Select the Create new button.

Step 10: Click Create button.

Step 11: After creating app service then click Finish button.

Step 12: Click the Publish button.

Step 13: Publish has been succeed.

Step 14: Now, go to Azure portal and select the App Services. After running the service, click Get function URL by copying it. Then, paste it in the below client sample (which will request the Azure Functions, to perform PowerPoint Presentation to image conversion using the template PowerPoint document). You will get the output image as follows.

Steps to post the request to Azure Functions

Step 1: Create a console application to request the Azure Functions API.

Step 2: Add the following code snippet into Main method to post the request to Azure Functions with template PowerPoint document and get the resultant image.

C#

//Reads the template PowerPoint document.
FileStream fs = new FileStream(@"../../Data/Input.pptx", FileMode.Open, FileAccess.ReadWrite, FileShare.ReadWrite);
fs.Position = 0;
//Saves the PowerPoint document in memory stream.
MemoryStream inputStream = new MemoryStream();
fs.CopyTo(inputStream);
inputStream.Position = 0;
try
{
    Console.WriteLine("Please enter your Azure Functions URL :");
    string functionURL = Console.ReadLine();
    //Create HttpWebRequest with hosted azure functions URL.                
    HttpWebRequest req = (HttpWebRequest)WebRequest.Create(functionURL);
    //Set request method as POST
    req.Method = "POST";
    //Get the request stream to save the PowerPoint document stream
    Stream stream = req.GetRequestStream();
    //Write the PowerPoint document stream into request stream
    stream.Write(inputStream.ToArray(), 0, inputStream.ToArray().Length);
    //Gets the responce from the Azure Functions.
    HttpWebResponse res = (HttpWebResponse)req.GetResponse();
    //Saves the image stream.
    FileStream fileStream = File.Create("PPTXtoImage.Jpeg");
    res.GetResponseStream().CopyTo(fileStream);
    //Dispose the streams
    inputStream.Dispose();
    fileStream.Dispose();
}
catch (Exception ex)
{
    throw;
}

From GitHub, you can download the console application and Azure Functions v4.

Click here to explore the rich set of Syncfusion PowerPoint Library (Presentation) features.

An online sample link to convert PowerPoint Presentation to image in ASP.NET Core.