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Video camera has a brightness correction algorithm and it was used incorrectly.

So I want to apply similar algorithm to the video. The video is static (camera stays in place and doesn't move) but brightness and contrast varies because of autocorrection. I want to freeze them at some appropriate level. I can select a large area (more than 15%), where the picture never changes. I want that area to become reference area, i. e. basis for color correction of the whole frame. It should correct colors in that way, that average brightness and contrast of the reference area is the same for all frames (and I want to specify corresponding values).

What tools and options I can use to achieve that?

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If you want the “best possible results” I would recommend the following workflow, or similar variation thereof:

  • Export your captured video source to a JPG Image Sequence. This will create a JPG for each discrete frame of the video. If you want ultimate color control, with no loss of quality due to JPG compression, you can export instead a TIF sequence, but the size of your output will be 30-50 times larger for HD content.

  • Second, using Photoshop, open a single frame.

  • Being your camera is a lockdown shot, choose your reference pixel to be used to determine brightness. I would recommend picking a pixel that has a luminance value of medium grey.

  • Save your Frame as “Reference.jpg”

  • Close the File.

  • Now open a new different frame from the JPG sequence.

  • Record an Action Sequence that:

1) Opens Reference.jpg. Then uses the Adobe Keyboard command for select previous document.

2) Uses the Match Color Edit Command -> Under Edit Tab

3) Grabs the color value on the open new frame (the one you just opened).

4) Matches the color value to the Reference.jpg file for the exact same reference area.

5) Youll have to play with the parameters adjusting Fuzziness, Threshold, Etc, to get the settings right.

6) Apply Match Color Command.

7.) Close Reference.jpg

8.) End Recording of Action Sequence.

Then... Use Image Processor within Bridge to Batch your JPG Sequence Files. Select your input directory, output directory, and check th box “Run Action on Processed Files” - Select the Recorded Action.

Run the Image Processor.

This will give you the best possible results, specifically if you use TIF and work in a 16 Bit Workspace.

Hope this helps.

  • Just checked it. Yes, that works, but it is near 60 times slower then the video. So I need a minute to process a second of the video having 50 fps. – Qwertiy Apr 18 '18 at 20:52
  • Yea its very slow. But its really the way to acheive the best results. Honestly, this workflow can be applied to a number of image adjustment / filters. There are simply things that only photoshop can do, or simply does better, or you have far more accurate control of what is being done. So your system is running at 1 hour per Minute. You could use multiple systems to split the work, or just render over a few nights. – McFlySoHigh Apr 20 '18 at 1:08

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