Encode uploaded video files using php to .flv

My platform开发者_如何学运维 is PHP JOOMLA MYSQL. I want to encode and load uploaded video files of different formats to .flv. I want this to implement in a video upload site where the users can see the videos in front-end after uploading and also I want to implement download options for them in mp4 and flv. Any help would be appreciated and thanks in advance to have a good reply for this

You can use the powerful ffmpeg to encode the videos once they're uploaded to your server.

And here's a nice tutorial.