How to repair a broken section of a finished video without re-editing it

Last updated 2026-09-05 · 8 min read

What is the short version?

When nine sections of a delivered film are broken and the other hours of work are fine, rebuilding is the wrong instinct. A patch that goes onto the master you already have cannot disturb anything outside the windows it touches.

1. Go to Vizard Agent with the exported file and your list.
2. Give the start and end of every faulty interval.
3. Say the rest of the production must not be rebuilt.

What do you need before you start?

The list is the work. Timecodes down to the millisecond, taken from the exported file rather than from a timeline, and an end time defined as the first frame where the picture comes back — that definition removes the argument about whether a boundary frame is in or out.

• The exported file you are looking at.
• Every interval, start and end.
• What is wrong in each one.
• What the frame should show instead.
• Whether the duration is fixed. Usually yes.

What do you type into Vizard Agent?

Say "targeted repair" and say it plainly. A list of nine broken sections reads very naturally as a brief for a new version, and a new version is the one thing you do not want when the rest of the film has already been approved.

Prompt

Variants worth knowing:

• "Targeted repair." The words that stop a rebuild.
• "The first frame where the picture returns." Removes boundary ambiguity.
• "Preserve the total duration." Unless you name an exception.

What does Vizard Agent actually do?

Here is the order Vizard Agent worked in on a real long-form documentary with nine broken title sections. Notice how much of it happens before any repair is built: the fault is looked at as a set rather than one interval at a time.

1. Confirms the master files exist and grabs frames from every defective interval.
2. Tiles the defective cards together so the fault can be seen as a pattern.
3. Samples the underlying footage at the same times to confirm good picture exists.
4. Looks at the presenter under two of the broken cards specifically.
5. Draws the replacement graphic and previews one on a real frame.
6. Builds a patch for each interval from the underlying footage.
7. Re-cuts the patches with correct seeking when the first pass lands wrong.
8. Composites the patches onto the existing master.
9. Tiles the first and last frame of every repaired interval.
10. Checks the frame just after each interval as well.
11. Confirms each title is now fully readable and no longer clipped.
12. Uploads the repaired full-resolution master.
13. Locates the exact frame for a requested hard ending.
14. Tries a stream copy first, then encodes a hard cut when it is not exact.
15. Verifies the final duration and that the unwanted moment is gone.

Step three is the step that decides whether a repair is even possible. If the correct picture never existed at those times, this becomes a re-render; if it did, the patch is a compositing job and the rest of the film is safe.

Step ten is the one people forget. A patch almost always looks right in the middle and wrong at the edges, so the frame immediately after each repaired window is where a one-frame overlap or a missing frame shows itself.

What does the result look like?

The same film, at the same length, with every broken window replaced by what should have been there — and everything outside those windows still the delivery you already had and approved. The narration Vizard Agent left alone runs untouched from beginning to end.

If a hard ending was requested too, it lands on the exact frame you named.

When does this not work well?

A patch needs something correct to patch with. Where the underlying picture is genuinely missing rather than covered, or the fault runs through the whole film rather than sitting in defined windows, a repair is not the cheaper route.

• No good picture underneath. Nothing to composite in.
• A fault everywhere. That is a re-render, not a patch.
• Audio faults. These need the mix, not the master.
• Vague intervals. "Somewhere near the middle" cannot be patched.
• A heavily compressed export. The patch inherits its quality.

How do you fix a result that came back wrong?

Give the interval and what you still see. Vizard Agent keeps the window list and the patch it built for each one, so a note about the third interval rebuilds only the third, and the other eight stay exactly as they were verified.

• "This one is still black." That window rebuilt and re-checked.
• "The text is still clipped." Redrawn with proper margins.
• "There is a jump at the end of a patch." Boundary frames recounted.
• "The duration changed." Re-normalised to the original length.

How does Vizard Agent compare to doing it yourself?

By hand, nine broken windows in a long film usually means opening the project, and opening the project means everything is once again in play. The alternative, patching an export, is fiddly precisely at the boundaries, which is where a hand-placed patch tends to go wrong.

Common questions

Do I have to give exact timecodes? Yes, to the millisecond. Vizard Agent repairs what you can define.

Can it find the faults itself? Sometimes. But your list is authoritative, and Vizard Agent starts from it.

Will the audio be touched? No. Vizard Agent patches picture only unless you ask otherwise.

Does the file get re-encoded? Only where it must. Vizard Agent keeps the untouched parts as they are.

Can it also trim the ending? Yes. Give the exact time and Vizard Agent verifies the result.

What if a stream copy is not frame-accurate? Vizard Agent falls back to a hard encode and measures the duration.

How do I know the patch fits? Vizard Agent shows you the first and last frame of every window.

Can it fix clipped on-screen text? Yes. Vizard Agent redraws it with margins and confirms readability.

What about a freeze rather than a black frame? Same method. Name the interval and Vizard Agent patches it.

Will the runtime stay the same? Yes, unless you name an exception to that rule.

Can I send more intervals later? Yes. Vizard Agent patches the current master again.

Does it keep the original resolution? Yes. Vizard Agent repairs the full-resolution file.

Can it show me a before and after? Yes. Ask Vizard Agent for frames from each window.

Why not just re-render the whole thing? Because a re-render puts every approved decision back at risk to fix nine windows that a patch can reach directly.