adjusting sound after video upload?

Hi,

A team of developers is creating a website for me on which people can upload short videos (15-20 seconds). Users will tell short stories and visitors see related videos one after another. The problem is the sound; there is a big difference in sound volume between the videos. On other sites (e.g. YouTube) the videos are usually longer, so some difference in volume is no problem. You just adjust it. But because the videos on my site are so short, adjusting becomes an issue (while adjusting the video is already finished). I want the volume of the videos to be about the same for all videos; or at least no huge differences.
Is this possible to do after uploading (manually in the player by the uploader or automatically for all videos)? Or can this sort of sound adjusting only be done before uploading?

Thanks in advance

Post-processing the video would be one option, but this is going to create a heavy server load. Basically, for each uploaded video, you'd have to use a CRON or scheduled task to make whatever "adjust volume" script run. This would be very intensive server work. In reality, it would need to be done by a dedicated server, not just a regular hosted one.

Other option is to have your videos played in a custom Flash or Silverlight video player. Then, they could have the volume controlled while being viewed.

Thanks for your reply PeejAvery, this is very helpfull. I will discuss it with the developers.