How to remove flickering from image?

Question

While taking photos at a wedding, I had flickering issues. One of the priests asked me to put my camera to silent mode and didn't notice that I'm taking photos with flickers then.

How can I fix the flickering?

Answer 1

Slightly different technique from the ones expounded in the answer linked on the comments. Using Gimp but PS should be able to do it too.

You are fortunate enough to have a plain wall in the background, so from that we can extract the actual flicker information, if we assume that the wall should be a uniform color to start with.

So:

• In the top left corner, sample the colors in the middle of a light band (around 144px down in you image) and the middle of the neighboring dark band (226px down) and assign them respectively to the Foreground and background colors.
• Create the following layer structure:
  • Your image at the bottom
  • Above it, a layer group that you put in Divide mode
  • In the layer group two layers, the top one being also in Divide mode
  • Bucket fill these two layers with the Foreground color (light band color)
• This should produce the initial image
• Set the blend tool to:
  • Gradient: Foreground to background (RGB)
  • Shape: Bi-linear
  • Repeat: Triangular wave
• Create a vertical blend on the bottom layer in the group, starting from the middle of a light band, to the middle of the neighboring dark band. If you look at the whole image when doing this, the positions of the start and end of the blend are quite easy to determine because the image changes radically when you are close. The two places to look are:
  • The head of the person in focus
  • The top of the face mask of the person behind him (if the blend isn't correct the face mask will be overblown)
• You can further improve things by tweaking the gradient on the spot

Result: