Depends how bad it looks. Most editors like Premiere or Pinnacle or Corel Video Studio offer "Color Correction", which encompasses Hue, Saturation, Brightness, Contrast and Gamma. But you have said that it's "not very readable" -- and, as you know, you can't polish cow dung. I know there's a stack of people who have stuck to Camtasia with its huge AVI (outdated format container) files and it's periodical glitches and grainy recording.