High Volume best accommodation for video and audio on the website?

I'm thinking of a business selling video and audio clips for use in broadcast, commercial or personal project. Anyone have suggestions for a reliable hosting service that can serve large video files (500 MB or more). Il server avrebbe bisogno anche di avere un pacchetto di conversione, come ffmpeg Installato per il video di fornire ridimensionamento Anteprime with a watermark. Of course, I would prefer cheap and then start the service scale as it grows. I like a "pay-as" type of service! Neither far my research has made a perfect solution.