An app to create an image from first page of PDF

Can anyone recommend an app that will create an image for any given pdf. This is for a website, the site already has thousands of pdfs stored. I only wish to create the image of the pdf as and when I need it.

For example a webpage will check a list of ten pdf's, if no image available then create one. So I am not interested in a tool that converts pdfs by file location, I want to be able to call it when needed to create the image. Ideaaly i would like to have some control over quality and si开发者_StackOverflow社区ze of the image created.

Any help would be much appreciated?

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We use Aspose.Pdf.Kit for this task. It's a commercial library. This is a usage example for your specific task.