How to make the background colour and lighting consistent in a video
Upload the clip to Vizard Agent, say which part of the picture looks uneven, and say what must be left alone. Vizard Agent measures which pixels move across the whole clip before touching anything, isolates the subject from the background, evens out the background's colour and lighting, and then checks that the subject's pixels are unchanged.
What do you type into Vizard Agent?
Say the area and the exception in the same sentence. Vizard Agent treats the protected thing as a hard constraint rather than a preference, and naming it explicitly is what turns a general colour pass into a targeted one. The protected part is the one thing it cannot infer, and the part a colour adjustment is most likely to damage.
Prompt
What does Vizard Agent actually do?
Any adjustment strong enough to even out the background also lands on the thing in front of it. So almost half the run is measurement before a single pixel changes, because the question "what is safe to adjust" has an answer that can be computed rather than guessed. In the session behind this article it:
- Probed the clip, extracted a grid of frames and pulled key frames at full resolution rather than judging from thumbnails.
- Analysed the camera motion, differenced the frames against each other and built a motion-variance map showing which pixels move and which are static.
- Tiled crops of the subject from several points in time into one grid, and measured colour, brightness and contrast statistics for each region of the background.
- Harmonised the background with an image edit, resized the result back to the clip's exact dimensions, and checked the subject's pixels for any difference.
- Delivered at the source's own 540x960, H.264, 30fps, 5.3 seconds, because a colour job should not quietly change the resolution.
When does this not work well?
Evening out a background means inventing a version of it that was never filmed, and the more of the frame that has to be invented, the more likely it is to show. Vizard Agent works within what the footage supports, and no measurement makes a badly lit shot into a well lit one. Hard shadows are objects, not lighting variation, and reflections of the subject give the change away.
Common questions
Will it change my product or subject? No, when you say not to. Vizard Agent isolates it and checks afterwards that those pixels are unchanged.
Can it match two different clips to each other? Yes. Say which one is the reference and Vizard Agent measures both.
Is this the same as colour grading? No. Grading sets a look for the whole picture; Vizard Agent evens out one region and leaves everything else alone.