I have a couple of video clips made by my little Canon A520 digital camera. On video mode it is very sensitive to light changes and a couple of times on videos taken indoors the simple fact of the sun going behind a cloud outside, or somebody standing in front of the window has made the clip darken considerably. Too much. How can I fix this? Using, for instance, Virtual Dub? Must I select the affected area and cut it out and brighten that section and then join it back in? Or is there a tool that will level the brightness throughout the clip perhaps? Or is there a prog that makes doing this easier and not so liable to a sudden jump in brightness as I get when I cut the bit out, brighten in and then stick it back in? I have got that expensive fancy prog Premier Pro but I never use it. It is too complicated right from the beginning where it asks about presets and when I consulted their forum for help all their gurus told me my source material was too low class for their high class product and told me to go away and get a uni degree in video editing first. But I mention it because a more rational forum (hooray for afterdawn) may find it a useful product and have a simple set of instructions for me on how to use it for, for instance, this problem. And then again: it may have nothing to do with it. Fine. Please forgive my mentioning it. regards, ab
I think there is something in Avisynth that does it. Take a look at the "autogain" description in ColorYUV: http://avisynth.org/mediawiki/ColorYUV
One of Jimmy Ruska's VirtualDub tutorials covers the use of the 'blend' option available to some filters. In this case you would select a brightness level and apply it to the sections where it need lightening. http://youtube.jimmyr.com/tutorials/Applying_Filters_to_a_Range_of_Frames_in_Virtualdub.php