When a camera, drone or phone stops recording suddenly, because the battery died, the card filled up or the app crashed, the video file often won’t open. Its picture and sound are usually all there. What’s missing is the index: the part, written last, that tells a player where every frame is. Reco’s Fix a Video rebuilds that index on your Mac, using a clip that plays from the same camera as a pattern.
It’s free, it works on MP4 and MOV files, and nothing is uploaded.
When to use it
- A clip that was recording when the camera or drone lost power.
- A recording that stopped because the card was full.
- A video that QuickTime Player won’t open even though the file is still its full size, so the data is clearly there.
Videos found by a scan in Reco that are marked Needs repair are the same problem. You can repair them from the results with the Repair button above them (for example, Repair 3 videos…), the same way.
How to fix a video
- Open Fix a Video from More ways Reco can help on the first screen, or from the Tools menu. You can also drop the video straight onto its card.
- Drop in the video that won’t play, or click Choose a video…. Reco checks it first and tells you what it sees: its index is missing (what Reco can rebuild), its index is intact (the damage is in the picture itself, which this can’t fix), or it doesn’t look like a camera video at all.
- Pick a pattern clip. Reco offers videos from the same folder. Choose one that plays and was recorded by the same camera with the same settings: resolution, frame rate and codec.
- Click Fix this video. The repaired copy is saved beside the original as “name (repaired)”. When it’s done, Reco shows how long the video is and offers Show in Finder.
If the broken video is on a drive Reco is recovering files from, it asks for a folder on a different drive instead, so nothing new is written where lost files may still be waiting.
What it can’t do
- It needs a clip from the same camera. A pattern from a different camera, or shot at different settings, is the most common reason a repair fails. Card shoots usually leave other clips on the card that work.
- Some sound can’t be rebuilt yet. Some cameras record compressed sound that Reco can’t rebuild, so the repaired copy plays with picture only. Reco tells you when that happens.
- It doesn’t fix damaged picture. If the index is intact but frames are corrupted, a pattern clip doesn’t help, and Reco says so before you start.
- It can’t repair what isn’t there. If part of a clip was overwritten, that part is gone.
The original file is never changed, so trying costs nothing. If a repair fails, pick another pattern clip and try again.
If the video was deleted too
If the clip isn’t on the card any more, scan the card with Reco first. See free data recovery for Mac and fixing a corrupted MP4 or MOV. Videos that come back without an index are marked Needs repair, and you can repair them right there, saving the repaired copies to a different drive. Reco learns the camera’s settings from the clips found on the same card.
Questions
Why won’t my MP4 or MOV play after the camera died?
Cameras write a video’s index, the part that tells players where each frame is, when recording stops. If the battery dies or the card fills up first, the picture and sound are there but the index isn’t, so players refuse the file.
Why does Reco need a second video?
The missing index holds the camera’s settings. A clip that plays, recorded by the same camera with the same resolution, frame rate and codec, lets Reco learn them and rebuild the broken one.
Is my video uploaded anywhere?
No. The repair happens entirely on your Mac.
Can Reco fix any corrupted video?
No. It fixes videos whose index is missing. If the index is intact and the picture itself is damaged, Reco says so, because a pattern clip can’t fix that.