|A cool image from the Hubble Space Telescope|
which has been post processed by Judy Schmidt - check out
iMovie is great to throwing together a quick video, but it lacks some key video processing features like noise reduction.
Now, if you want to produce an amazingly complex video which is going to win awards, iMovie is not going to fit the bill. It is, on the other hand, just find for stitching together a piece for Youtube etc. In the modern world of video where the content is king not the post processing, lighting and directorship, this is enough.
But what if that content is a bit noisy? What if the camera was struggling with the light levels? Sadly, iMovie is not going to help you one little bit. However, ffmpeg can. It has a interpolation filter which works very well. As for all interpolation filters - one is going to see some 'smearing' of motion but for reasonably high frame rate video (24 fps or above) the effect is quite pleasing.
First - get ffmpeg.
This is a command line tool. If you do not really understand the command line, best stop reading now.
Next - read this post (section 5 is on denoising).
The post shows a bunch of other interesting filtering options. I am not going to pretend I worked all this out and then simply regergitate the author's work - nope - go read :)
Then you can use this command line.
Yes - I know you are just going to copy and paste this command line and try it. Then eventually you might go read about the parameters and how to tweak them. But for now - here is your cut and paste.
./ffmpeg -i IMG_2192.MOV -vf "yadif,hqdn3d=2.0:2.0:10:10,scale=1280:720" -strict -2 output.mp4
Finally, here is a video I processed this way as an example:
A video on reverb ambience which has been
filtered using ffmpeg to reduce the low light