Make 1st Slide of PowerPoint file to be the Post thumbnail preview image

I’m building a website for a client.. The website will only accept PowerPoint files to be uploaded in our server by our future members and soon we will start accepting online links.. I would like to ask for your help. We need to show the first slide of the PowerPoint file as the thumbnail preview image post without asking our members to upload .jpg files for the featured image. We want to automate the process.. by not making .jpg files from each PowerPoint files submitted to the website..

Hope to hear from you soon and I really appreciate your time for giving a me solution for this matter..

Thank You.

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