DO you have the rights to use these videos? Depending on how you are presenting this footage, there might be legal issues galore in doing this. Recutting stuff on youtube to put back on youtube as a compilation that you do as a hobby...people might turn a blind eye. But other uses might cause issues. And claiming ignorance as "just the editor" might not cut it.
What you see is what you get. WYSISWYG. People shoot with poor cameras that compress, then compress again to send to YouTube, that again will compress the footage. Then you come along to rip...then recompress. Unless you have high end...REALLY high end software and hardware...you aren't going to be able to fix this. There are options for occasional dead pixels...the odd dropout.
Hi Shane, thanks for getting back to me. I thought it might be a lost cause to be honest!
I am aware of the copyright issues that may arise, so I have just bought this up with my client and we shall see what the outcome is. I don't believe it's going to be distributed for profit or anything but thanks for the heads up anyway!