Ajax upload video and create animated gif preview

Hello. I own an adult webcam site. Performers have the option of uploading videos to sell on the site. I am looking for someone to create a new video upload/submission script. Performers should be able to upload a compatible video of their choice from their computer. Performers will need to set the price of the video and the title/description. Once the upload is started there should be a progress bar showing the status of the upload. Once the upload has been succesful I need the video to be encoded to flv format (ffmpeg installed on the server) automatically again showing the status of the video conversion of possible). Once conversion is complete I would also like to make an image preview of the uploaded video. The best way of doing this is to take some screenshots of the video every x amount of seconds and then join them together in an animated gif. Once everything is complete I would like to display a message to the performer that their video has been successfully uploaded to our site and it is pending review. If there are any errors along the way with the process the performers should be notified with as much details as possible (incorrect file types, codecs not supported etc)