How to keep faint text from vanishing when you drop the background out
Tell Vizard Agent to keep the text and drop the background behind it. It tests several cut-off levels and shows you the frames rather than choosing one silently, then goes looking for the transitions where the text fades, because a level that holds every word in the middle of a shot will lose them as they arrive and leave.
What do you type into Vizard Agent?
Ask to see the tests. A threshold is a number, and the difference between a good one and a bad one is invisible in a description and obvious on a frame, so the useful request to Vizard Agent is for the comparison rather than the result. Say which text survives too: "keep the white text" excludes greys and logos.
Prompt
What does Vizard Agent actually do?
Comparing the source frame with the rendered one shows the text was there and faint, not missing, which is a different problem with a different fix. A single global cut-off has to be low enough for the faintest frame and high enough to reject the background; when no number does both, a local-contrast mask does. In the session behind this article it:
- Viewed the source frames of a series of text videos before changing anything, then tested several black-and-white thresholds against the real text.
- Showed the tests so the cleanest could be chosen, rendered the white-on-black version as a 4K vertical and reviewed it with its audio.
- Inspected a close-up of the text, then the transition where the text briefly disappeared, viewing the source and rendered transition frames together.
- Tested lower thresholds to keep the fading text, and a local-contrast mask for the faintest frames.
- Tested thresholds across the whole montage to isolate only the white text, then rendered the high-clarity version and checked the text close up.
When does this not work well?
The text has to be separable from its background by brightness alone. Coloured text on a light background, text over a bright photograph, or a shot where the background is as bright as the letters gives Vizard Agent's threshold nothing to work with. Thin, light typefaces break up at any cut-off, and heavy compression makes edges blocky.
Common questions
Can I see the options? Yes, and you should. Vizard Agent renders the tests as frames.
Why does text vanish in the fades? Because it drops below the cut-off. Vizard Agent switches to a mask there.
What if one scene needs a different level? Then Vizard Agent applies a different one to that scene alone.