If you run a popular website then the chances are that a lot of people will want to upload videos. This can put serious strain on the servers of whatever online video conversion service you use. It will mean the speed of upload for the videos will be slow and it may even cause long queues of people waiting to upload their videos.
To avoid that sort of hassle you should use a service that is able to cope with convert image to svg & lots of videos being uploaded simultaneously. Ideally you should use a online video converter service that uses the Amazon Cloud system, as this allows for the quickest uploading of files with little to no queues.