How to upscale a video without it distorting people's faces
Tell Vizard Agent what you want sharper and that nobody's face may change. It tests the upscaler on a short piece before committing, puts a tight punch-in from the original beside the enlarged version so you can compare them, and blends the two so the subject gains detail while the background faces stay as they were filmed.
What do you type into Vizard Agent?
Set the limit in the same sentence as the request. Enhancement is a spectrum and the default sits somewhere in the middle, which is fine for a wall and not fine for a face. Saying so up front is cheaper than undoing it later, and asking Vizard Agent for a short test first settles it cheaply.
Prompt
What does Vizard Agent actually do?
An upscaler invents detail. On the person you punched in on, that's what you want; on the faces behind them it invents features those people don't have. So the upscale is never simply applied: it's tested, compared, and then blended onto the subject while the background stays as filmed. In the session behind this article it:
- Checked whether an upscaling tool was available and what it cost, cut the relevant excerpts of a recorded event into one file and started the enlargement.
- When the enlargement failed, checked why rather than simply retrying, and tested a ten-second piece to see whether length was the problem.
- Compared a tight punch-in from the original against the enlarged one, side by side at the same moment.
- Tested a blend that enlarged the speaker and left the rest of the frame original.
- Ran the enlargement on all the excerpts in parallel, rewired the build to blend the result in, and verified every enlarged excerpt before it went into the cut.
- Tested brightness lifts on faces, comparing close-ups before and after.
When does this not work well?
Upscaling can't recover what was never recorded. Very soft footage, a heavy crop into a small area, or a face a dozen pixels wide gives the tool nothing to work from, so it invents, and inventing a face is the failure you're trying to avoid. With heavy compression the blocks get sharpened into detail, fast motion can flicker, and invented detail is not evidence.
Common questions
Will it change faces? Not if you say so. Vizard Agent keeps the enlargement off them.
Can it sharpen only the speaker? Yes. Vizard Agent blends the enlargement onto part of the frame.
Can I see a test first? Yes, and you should. Ten seconds is enough for Vizard Agent to show you.